1// SPDX-License-Identifier: GPL-2.0
2//
3// STMicroelectronics STM32 SPI Controller driver
4//
5// Copyright (C) 2017, STMicroelectronics - All Rights Reserved
6// Author(s): Amelie Delaunay <amelie.delaunay@st.com> for STMicroelectronics.
7
8#include <linux/bitfield.h>
9#include <linux/debugfs.h>
10#include <linux/clk.h>
11#include <linux/delay.h>
12#include <linux/dmaengine.h>
13#include <linux/interrupt.h>
14#include <linux/iopoll.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/platform_device.h>
18#include <linux/pinctrl/consumer.h>
19#include <linux/pm_runtime.h>
20#include <linux/reset.h>
21#include <linux/spi/spi.h>
22
23#define DRIVER_NAME "spi_stm32"
24
25/* STM32F4/7 SPI registers */
26#define STM32FX_SPI_CR1			0x00
27#define STM32FX_SPI_CR2			0x04
28#define STM32FX_SPI_SR			0x08
29#define STM32FX_SPI_DR			0x0C
30#define STM32FX_SPI_I2SCFGR		0x1C
31
32/* STM32FX_SPI_CR1 bit fields */
33#define STM32FX_SPI_CR1_CPHA		BIT(0)
34#define STM32FX_SPI_CR1_CPOL		BIT(1)
35#define STM32FX_SPI_CR1_MSTR		BIT(2)
36#define STM32FX_SPI_CR1_BR_SHIFT	3
37#define STM32FX_SPI_CR1_BR		GENMASK(5, 3)
38#define STM32FX_SPI_CR1_SPE		BIT(6)
39#define STM32FX_SPI_CR1_LSBFRST		BIT(7)
40#define STM32FX_SPI_CR1_SSI		BIT(8)
41#define STM32FX_SPI_CR1_SSM		BIT(9)
42#define STM32FX_SPI_CR1_RXONLY		BIT(10)
43#define STM32F4_SPI_CR1_DFF		BIT(11)
44#define STM32F7_SPI_CR1_CRCL		BIT(11)
45#define STM32FX_SPI_CR1_CRCNEXT		BIT(12)
46#define STM32FX_SPI_CR1_CRCEN		BIT(13)
47#define STM32FX_SPI_CR1_BIDIOE		BIT(14)
48#define STM32FX_SPI_CR1_BIDIMODE	BIT(15)
49#define STM32FX_SPI_CR1_BR_MIN		0
50#define STM32FX_SPI_CR1_BR_MAX		(GENMASK(5, 3) >> 3)
51
52/* STM32FX_SPI_CR2 bit fields */
53#define STM32FX_SPI_CR2_RXDMAEN		BIT(0)
54#define STM32FX_SPI_CR2_TXDMAEN		BIT(1)
55#define STM32FX_SPI_CR2_SSOE		BIT(2)
56#define STM32FX_SPI_CR2_FRF		BIT(4)
57#define STM32FX_SPI_CR2_ERRIE		BIT(5)
58#define STM32FX_SPI_CR2_RXNEIE		BIT(6)
59#define STM32FX_SPI_CR2_TXEIE		BIT(7)
60#define STM32F7_SPI_CR2_DS		GENMASK(11, 8)
61#define STM32F7_SPI_CR2_FRXTH		BIT(12)
62#define STM32F7_SPI_CR2_LDMA_RX		BIT(13)
63#define STM32F7_SPI_CR2_LDMA_TX		BIT(14)
64
65/* STM32FX_SPI_SR bit fields */
66#define STM32FX_SPI_SR_RXNE		BIT(0)
67#define STM32FX_SPI_SR_TXE		BIT(1)
68#define STM32FX_SPI_SR_CHSIDE		BIT(2)
69#define STM32FX_SPI_SR_UDR		BIT(3)
70#define STM32FX_SPI_SR_CRCERR		BIT(4)
71#define STM32FX_SPI_SR_MODF		BIT(5)
72#define STM32FX_SPI_SR_OVR		BIT(6)
73#define STM32FX_SPI_SR_BSY		BIT(7)
74#define STM32FX_SPI_SR_FRE		BIT(8)
75#define STM32F7_SPI_SR_FRLVL		GENMASK(10, 9)
76#define STM32F7_SPI_SR_FTLVL		GENMASK(12, 11)
77
78/* STM32FX_SPI_I2SCFGR bit fields */
79#define STM32FX_SPI_I2SCFGR_I2SMOD	BIT(11)
80
81/* STM32F4 SPI Baud Rate min/max divisor */
82#define STM32FX_SPI_BR_DIV_MIN		(2 << STM32FX_SPI_CR1_BR_MIN)
83#define STM32FX_SPI_BR_DIV_MAX		(2 << STM32FX_SPI_CR1_BR_MAX)
84
85/* STM32H7 SPI registers */
86#define STM32H7_SPI_CR1			0x00
87#define STM32H7_SPI_CR2			0x04
88#define STM32H7_SPI_CFG1		0x08
89#define STM32H7_SPI_CFG2		0x0C
90#define STM32H7_SPI_IER			0x10
91#define STM32H7_SPI_SR			0x14
92#define STM32H7_SPI_IFCR		0x18
93#define STM32H7_SPI_TXDR		0x20
94#define STM32H7_SPI_RXDR		0x30
95#define STM32H7_SPI_I2SCFGR		0x50
96
97/* STM32H7_SPI_CR1 bit fields */
98#define STM32H7_SPI_CR1_SPE		BIT(0)
99#define STM32H7_SPI_CR1_MASRX		BIT(8)
100#define STM32H7_SPI_CR1_CSTART		BIT(9)
101#define STM32H7_SPI_CR1_CSUSP		BIT(10)
102#define STM32H7_SPI_CR1_HDDIR		BIT(11)
103#define STM32H7_SPI_CR1_SSI		BIT(12)
104
105/* STM32H7_SPI_CR2 bit fields */
106#define STM32H7_SPI_CR2_TSIZE		GENMASK(15, 0)
107#define STM32H7_SPI_TSIZE_MAX		GENMASK(15, 0)
108
109/* STM32H7_SPI_CFG1 bit fields */
110#define STM32H7_SPI_CFG1_DSIZE		GENMASK(4, 0)
111#define STM32H7_SPI_CFG1_FTHLV		GENMASK(8, 5)
112#define STM32H7_SPI_CFG1_RXDMAEN	BIT(14)
113#define STM32H7_SPI_CFG1_TXDMAEN	BIT(15)
114#define STM32H7_SPI_CFG1_MBR		GENMASK(30, 28)
115#define STM32H7_SPI_CFG1_MBR_SHIFT	28
116#define STM32H7_SPI_CFG1_MBR_MIN	0
117#define STM32H7_SPI_CFG1_MBR_MAX	(GENMASK(30, 28) >> 28)
118
119/* STM32H7_SPI_CFG2 bit fields */
120#define STM32H7_SPI_CFG2_MIDI		GENMASK(7, 4)
121#define STM32H7_SPI_CFG2_COMM		GENMASK(18, 17)
122#define STM32H7_SPI_CFG2_SP		GENMASK(21, 19)
123#define STM32H7_SPI_CFG2_MASTER		BIT(22)
124#define STM32H7_SPI_CFG2_LSBFRST	BIT(23)
125#define STM32H7_SPI_CFG2_CPHA		BIT(24)
126#define STM32H7_SPI_CFG2_CPOL		BIT(25)
127#define STM32H7_SPI_CFG2_SSM		BIT(26)
128#define STM32H7_SPI_CFG2_SSIOP		BIT(28)
129#define STM32H7_SPI_CFG2_AFCNTR		BIT(31)
130
131/* STM32H7_SPI_IER bit fields */
132#define STM32H7_SPI_IER_RXPIE		BIT(0)
133#define STM32H7_SPI_IER_TXPIE		BIT(1)
134#define STM32H7_SPI_IER_DXPIE		BIT(2)
135#define STM32H7_SPI_IER_EOTIE		BIT(3)
136#define STM32H7_SPI_IER_TXTFIE		BIT(4)
137#define STM32H7_SPI_IER_OVRIE		BIT(6)
138#define STM32H7_SPI_IER_MODFIE		BIT(9)
139#define STM32H7_SPI_IER_ALL		GENMASK(10, 0)
140
141/* STM32H7_SPI_SR bit fields */
142#define STM32H7_SPI_SR_RXP		BIT(0)
143#define STM32H7_SPI_SR_TXP		BIT(1)
144#define STM32H7_SPI_SR_EOT		BIT(3)
145#define STM32H7_SPI_SR_OVR		BIT(6)
146#define STM32H7_SPI_SR_MODF		BIT(9)
147#define STM32H7_SPI_SR_SUSP		BIT(11)
148#define STM32H7_SPI_SR_RXPLVL		GENMASK(14, 13)
149#define STM32H7_SPI_SR_RXWNE		BIT(15)
150
151/* STM32H7_SPI_IFCR bit fields */
152#define STM32H7_SPI_IFCR_ALL		GENMASK(11, 3)
153
154/* STM32H7_SPI_I2SCFGR bit fields */
155#define STM32H7_SPI_I2SCFGR_I2SMOD	BIT(0)
156
157/* STM32MP25 SPI registers bit fields */
158#define STM32MP25_SPI_HWCFGR1			0x3F0
159
160/* STM32MP25_SPI_CR2 bit fields */
161#define STM32MP25_SPI_TSIZE_MAX_LIMITED		GENMASK(9, 0)
162
163/* STM32MP25_SPI_HWCFGR1 */
164#define STM32MP25_SPI_HWCFGR1_FULLCFG		GENMASK(27, 24)
165#define STM32MP25_SPI_HWCFGR1_FULLCFG_LIMITED	0x0
166#define STM32MP25_SPI_HWCFGR1_FULLCFG_FULL	0x1
167#define STM32MP25_SPI_HWCFGR1_DSCFG		GENMASK(19, 16)
168#define STM32MP25_SPI_HWCFGR1_DSCFG_16_B	0x0
169#define STM32MP25_SPI_HWCFGR1_DSCFG_32_B	0x1
170
171/* STM32H7 SPI Master Baud Rate min/max divisor */
172#define STM32H7_SPI_MBR_DIV_MIN		(2 << STM32H7_SPI_CFG1_MBR_MIN)
173#define STM32H7_SPI_MBR_DIV_MAX		(2 << STM32H7_SPI_CFG1_MBR_MAX)
174
175/* STM32H7 SPI Communication mode */
176#define STM32H7_SPI_FULL_DUPLEX		0
177#define STM32H7_SPI_SIMPLEX_TX		1
178#define STM32H7_SPI_SIMPLEX_RX		2
179#define STM32H7_SPI_HALF_DUPLEX		3
180
181/* SPI Communication type */
182#define SPI_FULL_DUPLEX		0
183#define SPI_SIMPLEX_TX		1
184#define SPI_SIMPLEX_RX		2
185#define SPI_3WIRE_TX		3
186#define SPI_3WIRE_RX		4
187
188#define STM32_SPI_AUTOSUSPEND_DELAY		1	/* 1 ms */
189
190/*
191 * use PIO for small transfers, avoiding DMA setup/teardown overhead for drivers
192 * without fifo buffers.
193 */
194#define SPI_DMA_MIN_BYTES	16
195
196/* STM32 SPI driver helpers */
197#define STM32_SPI_HOST_MODE(stm32_spi) (!(stm32_spi)->device_mode)
198#define STM32_SPI_DEVICE_MODE(stm32_spi) ((stm32_spi)->device_mode)
199
200/**
201 * struct stm32_spi_reg - stm32 SPI register & bitfield desc
202 * @reg:		register offset
203 * @mask:		bitfield mask
204 * @shift:		left shift
205 */
206struct stm32_spi_reg {
207	int reg;
208	int mask;
209	int shift;
210};
211
212/**
213 * struct stm32_spi_regspec - stm32 registers definition, compatible dependent data
214 * @en: enable register and SPI enable bit
215 * @dma_rx_en: SPI DMA RX enable register end SPI DMA RX enable bit
216 * @dma_tx_en: SPI DMA TX enable register end SPI DMA TX enable bit
217 * @cpol: clock polarity register and polarity bit
218 * @cpha: clock phase register and phase bit
219 * @lsb_first: LSB transmitted first register and bit
220 * @cs_high: chips select active value
221 * @br: baud rate register and bitfields
222 * @rx: SPI RX data register
223 * @tx: SPI TX data register
224 * @fullcfg: SPI full or limited feature set register
225 */
226struct stm32_spi_regspec {
227	const struct stm32_spi_reg en;
228	const struct stm32_spi_reg dma_rx_en;
229	const struct stm32_spi_reg dma_tx_en;
230	const struct stm32_spi_reg cpol;
231	const struct stm32_spi_reg cpha;
232	const struct stm32_spi_reg lsb_first;
233	const struct stm32_spi_reg cs_high;
234	const struct stm32_spi_reg br;
235	const struct stm32_spi_reg rx;
236	const struct stm32_spi_reg tx;
237	const struct stm32_spi_reg fullcfg;
238};
239
240struct stm32_spi;
241
242/**
243 * struct stm32_spi_cfg - stm32 compatible configuration data
244 * @regs: registers descriptions
245 * @get_fifo_size: routine to get fifo size
246 * @get_bpw_mask: routine to get bits per word mask
247 * @disable: routine to disable controller
248 * @config: routine to configure controller as SPI Host
249 * @set_bpw: routine to configure registers to for bits per word
250 * @set_mode: routine to configure registers to desired mode
251 * @set_data_idleness: optional routine to configure registers to desired idle
252 * time between frames (if driver has this functionality)
253 * @set_number_of_data: optional routine to configure registers to desired
254 * number of data (if driver has this functionality)
255 * @write_tx: routine to write to transmit register/FIFO
256 * @read_rx: routine to read from receive register/FIFO
257 * @transfer_one_dma_start: routine to start transfer a single spi_transfer
258 * using DMA
259 * @dma_rx_cb: routine to call after DMA RX channel operation is complete
260 * @dma_tx_cb: routine to call after DMA TX channel operation is complete
261 * @transfer_one_irq: routine to configure interrupts for driver
262 * @irq_handler_event: Interrupt handler for SPI controller events
263 * @irq_handler_thread: thread of interrupt handler for SPI controller
264 * @baud_rate_div_min: minimum baud rate divisor
265 * @baud_rate_div_max: maximum baud rate divisor
266 * @has_fifo: boolean to know if fifo is used for driver
267 * @has_device_mode: is this compatible capable to switch on device mode
268 * @flags: compatible specific SPI controller flags used at registration time
269 * @prevent_dma_burst: boolean to indicate to prevent DMA burst
270 */
271struct stm32_spi_cfg {
272	const struct stm32_spi_regspec *regs;
273	int (*get_fifo_size)(struct stm32_spi *spi);
274	int (*get_bpw_mask)(struct stm32_spi *spi);
275	void (*disable)(struct stm32_spi *spi);
276	int (*config)(struct stm32_spi *spi);
277	void (*set_bpw)(struct stm32_spi *spi);
278	int (*set_mode)(struct stm32_spi *spi, unsigned int comm_type);
279	void (*set_data_idleness)(struct stm32_spi *spi, u32 length);
280	int (*set_number_of_data)(struct stm32_spi *spi, u32 length);
281	void (*write_tx)(struct stm32_spi *spi);
282	void (*read_rx)(struct stm32_spi *spi);
283	void (*transfer_one_dma_start)(struct stm32_spi *spi);
284	void (*dma_rx_cb)(void *data);
285	void (*dma_tx_cb)(void *data);
286	int (*transfer_one_irq)(struct stm32_spi *spi);
287	irqreturn_t (*irq_handler_event)(int irq, void *dev_id);
288	irqreturn_t (*irq_handler_thread)(int irq, void *dev_id);
289	unsigned int baud_rate_div_min;
290	unsigned int baud_rate_div_max;
291	bool has_fifo;
292	bool has_device_mode;
293	u16 flags;
294	bool prevent_dma_burst;
295};
296
297/**
298 * struct stm32_spi - private data of the SPI controller
299 * @dev: driver model representation of the controller
300 * @ctrl: controller interface
301 * @cfg: compatible configuration data
302 * @base: virtual memory area
303 * @clk: hw kernel clock feeding the SPI clock generator
304 * @clk_rate: rate of the hw kernel clock feeding the SPI clock generator
305 * @lock: prevent I/O concurrent access
306 * @irq: SPI controller interrupt line
307 * @fifo_size: size of the embedded fifo in bytes
308 * @t_size_max: maximum number of data of one transfer
309 * @feature_set: SPI full or limited feature set
310 * @cur_midi: host inter-data idleness in ns
311 * @cur_speed: speed configured in Hz
312 * @cur_half_period: time of a half bit in us
313 * @cur_bpw: number of bits in a single SPI data frame
314 * @cur_fthlv: fifo threshold level (data frames in a single data packet)
315 * @cur_comm: SPI communication mode
316 * @cur_xferlen: current transfer length in bytes
317 * @cur_usedma: boolean to know if dma is used in current transfer
318 * @tx_buf: data to be written, or NULL
319 * @rx_buf: data to be read, or NULL
320 * @tx_len: number of data to be written in bytes
321 * @rx_len: number of data to be read in bytes
322 * @dma_tx: dma channel for TX transfer
323 * @dma_rx: dma channel for RX transfer
324 * @phys_addr: SPI registers physical base address
325 * @device_mode: the controller is configured as SPI device
326 */
327struct stm32_spi {
328	struct device *dev;
329	struct spi_controller *ctrl;
330	const struct stm32_spi_cfg *cfg;
331	void __iomem *base;
332	struct clk *clk;
333	u32 clk_rate;
334	spinlock_t lock; /* prevent I/O concurrent access */
335	int irq;
336	unsigned int fifo_size;
337	unsigned int t_size_max;
338	unsigned int feature_set;
339#define STM32_SPI_FEATURE_LIMITED	STM32MP25_SPI_HWCFGR1_FULLCFG_LIMITED	/* 0x0 */
340#define STM32_SPI_FEATURE_FULL		STM32MP25_SPI_HWCFGR1_FULLCFG_FULL	/* 0x1 */
341
342	unsigned int cur_midi;
343	unsigned int cur_speed;
344	unsigned int cur_half_period;
345	unsigned int cur_bpw;
346	unsigned int cur_fthlv;
347	unsigned int cur_comm;
348	unsigned int cur_xferlen;
349	bool cur_usedma;
350
351	const void *tx_buf;
352	void *rx_buf;
353	int tx_len;
354	int rx_len;
355	struct dma_chan *dma_tx;
356	struct dma_chan *dma_rx;
357	dma_addr_t phys_addr;
358
359	bool device_mode;
360};
361
362static const struct stm32_spi_regspec stm32fx_spi_regspec = {
363	.en = { STM32FX_SPI_CR1, STM32FX_SPI_CR1_SPE },
364
365	.dma_rx_en = { STM32FX_SPI_CR2, STM32FX_SPI_CR2_RXDMAEN },
366	.dma_tx_en = { STM32FX_SPI_CR2, STM32FX_SPI_CR2_TXDMAEN },
367
368	.cpol = { STM32FX_SPI_CR1, STM32FX_SPI_CR1_CPOL },
369	.cpha = { STM32FX_SPI_CR1, STM32FX_SPI_CR1_CPHA },
370	.lsb_first = { STM32FX_SPI_CR1, STM32FX_SPI_CR1_LSBFRST },
371	.cs_high = {},
372	.br = { STM32FX_SPI_CR1, STM32FX_SPI_CR1_BR, STM32FX_SPI_CR1_BR_SHIFT },
373
374	.rx = { STM32FX_SPI_DR },
375	.tx = { STM32FX_SPI_DR },
376};
377
378static const struct stm32_spi_regspec stm32h7_spi_regspec = {
379	/* SPI data transfer is enabled but spi_ker_ck is idle.
380	 * CFG1 and CFG2 registers are write protected when SPE is enabled.
381	 */
382	.en = { STM32H7_SPI_CR1, STM32H7_SPI_CR1_SPE },
383
384	.dma_rx_en = { STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_RXDMAEN },
385	.dma_tx_en = { STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_TXDMAEN },
386
387	.cpol = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_CPOL },
388	.cpha = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_CPHA },
389	.lsb_first = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_LSBFRST },
390	.cs_high = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_SSIOP },
391	.br = { STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_MBR,
392		STM32H7_SPI_CFG1_MBR_SHIFT },
393
394	.rx = { STM32H7_SPI_RXDR },
395	.tx = { STM32H7_SPI_TXDR },
396};
397
398static const struct stm32_spi_regspec stm32mp25_spi_regspec = {
399	/* SPI data transfer is enabled but spi_ker_ck is idle.
400	 * CFG1 and CFG2 registers are write protected when SPE is enabled.
401	 */
402	.en = { STM32H7_SPI_CR1, STM32H7_SPI_CR1_SPE },
403
404	.dma_rx_en = { STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_RXDMAEN },
405	.dma_tx_en = { STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_TXDMAEN },
406
407	.cpol = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_CPOL },
408	.cpha = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_CPHA },
409	.lsb_first = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_LSBFRST },
410	.cs_high = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_SSIOP },
411	.br = { STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_MBR,
412		STM32H7_SPI_CFG1_MBR_SHIFT },
413
414	.rx = { STM32H7_SPI_RXDR },
415	.tx = { STM32H7_SPI_TXDR },
416
417	.fullcfg = { STM32MP25_SPI_HWCFGR1, STM32MP25_SPI_HWCFGR1_FULLCFG },
418};
419
420static inline void stm32_spi_set_bits(struct stm32_spi *spi,
421				      u32 offset, u32 bits)
422{
423	writel_relaxed(readl_relaxed(spi->base + offset) | bits,
424		       spi->base + offset);
425}
426
427static inline void stm32_spi_clr_bits(struct stm32_spi *spi,
428				      u32 offset, u32 bits)
429{
430	writel_relaxed(readl_relaxed(spi->base + offset) & ~bits,
431		       spi->base + offset);
432}
433
434/**
435 * stm32h7_spi_get_fifo_size - Return fifo size
436 * @spi: pointer to the spi controller data structure
437 */
438static int stm32h7_spi_get_fifo_size(struct stm32_spi *spi)
439{
440	unsigned long flags;
441	u32 count = 0;
442
443	spin_lock_irqsave(&spi->lock, flags);
444
445	stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_SPE);
446
447	while (readl_relaxed(spi->base + STM32H7_SPI_SR) & STM32H7_SPI_SR_TXP)
448		writeb_relaxed(++count, spi->base + STM32H7_SPI_TXDR);
449
450	stm32_spi_clr_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_SPE);
451
452	spin_unlock_irqrestore(&spi->lock, flags);
453
454	dev_dbg(spi->dev, "%d x 8-bit fifo size\n", count);
455
456	return count;
457}
458
459/**
460 * stm32f4_spi_get_bpw_mask - Return bits per word mask
461 * @spi: pointer to the spi controller data structure
462 */
463static int stm32f4_spi_get_bpw_mask(struct stm32_spi *spi)
464{
465	dev_dbg(spi->dev, "8-bit or 16-bit data frame supported\n");
466	return SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
467}
468
469/**
470 * stm32f7_spi_get_bpw_mask - Return bits per word mask
471 * @spi: pointer to the spi controller data structure
472 */
473static int stm32f7_spi_get_bpw_mask(struct stm32_spi *spi)
474{
475	dev_dbg(spi->dev, "16-bit maximum data frame\n");
476	return SPI_BPW_RANGE_MASK(4, 16);
477}
478
479/**
480 * stm32h7_spi_get_bpw_mask - Return bits per word mask
481 * @spi: pointer to the spi controller data structure
482 */
483static int stm32h7_spi_get_bpw_mask(struct stm32_spi *spi)
484{
485	unsigned long flags;
486	u32 cfg1, max_bpw;
487
488	spin_lock_irqsave(&spi->lock, flags);
489
490	/*
491	 * The most significant bit at DSIZE bit field is reserved when the
492	 * maximum data size of periperal instances is limited to 16-bit
493	 */
494	stm32_spi_set_bits(spi, STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_DSIZE);
495
496	cfg1 = readl_relaxed(spi->base + STM32H7_SPI_CFG1);
497	max_bpw = FIELD_GET(STM32H7_SPI_CFG1_DSIZE, cfg1) + 1;
498
499	spin_unlock_irqrestore(&spi->lock, flags);
500
501	dev_dbg(spi->dev, "%d-bit maximum data frame\n", max_bpw);
502
503	return SPI_BPW_RANGE_MASK(4, max_bpw);
504}
505
506/**
507 * stm32mp25_spi_get_bpw_mask - Return bits per word mask
508 * @spi: pointer to the spi controller data structure
509 */
510static int stm32mp25_spi_get_bpw_mask(struct stm32_spi *spi)
511{
512	u32 dscfg, max_bpw;
513
514	if (spi->feature_set == STM32_SPI_FEATURE_LIMITED) {
515		dev_dbg(spi->dev, "8-bit or 16-bit data frame supported\n");
516		return SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
517	}
518
519	dscfg = FIELD_GET(STM32MP25_SPI_HWCFGR1_DSCFG,
520			  readl_relaxed(spi->base + STM32MP25_SPI_HWCFGR1));
521	max_bpw = 16;
522	if (dscfg == STM32MP25_SPI_HWCFGR1_DSCFG_32_B)
523		max_bpw = 32;
524	dev_dbg(spi->dev, "%d-bit maximum data frame\n", max_bpw);
525	return SPI_BPW_RANGE_MASK(4, max_bpw);
526}
527
528/**
529 * stm32_spi_prepare_mbr - Determine baud rate divisor value
530 * @spi: pointer to the spi controller data structure
531 * @speed_hz: requested speed
532 * @min_div: minimum baud rate divisor
533 * @max_div: maximum baud rate divisor
534 *
535 * Return baud rate divisor value in case of success or -EINVAL
536 */
537static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
538				 u32 min_div, u32 max_div)
539{
540	u32 div, mbrdiv;
541
542	/* Ensure spi->clk_rate is even */
543	div = DIV_ROUND_CLOSEST(spi->clk_rate & ~0x1, speed_hz);
544
545	/*
546	 * SPI framework set xfer->speed_hz to ctrl->max_speed_hz if
547	 * xfer->speed_hz is greater than ctrl->max_speed_hz, and it returns
548	 * an error when xfer->speed_hz is lower than ctrl->min_speed_hz, so
549	 * no need to check it there.
550	 * However, we need to ensure the following calculations.
551	 */
552	if ((div < min_div) || (div > max_div))
553		return -EINVAL;
554
555	/* Determine the first power of 2 greater than or equal to div */
556	if (div & (div - 1))
557		mbrdiv = fls(div);
558	else
559		mbrdiv = fls(div) - 1;
560
561	spi->cur_speed = spi->clk_rate / (1 << mbrdiv);
562
563	spi->cur_half_period = DIV_ROUND_CLOSEST(USEC_PER_SEC, 2 * spi->cur_speed);
564
565	return mbrdiv - 1;
566}
567
568/**
569 * stm32h7_spi_prepare_fthlv - Determine FIFO threshold level
570 * @spi: pointer to the spi controller data structure
571 * @xfer_len: length of the message to be transferred
572 */
573static u32 stm32h7_spi_prepare_fthlv(struct stm32_spi *spi, u32 xfer_len)
574{
575	u32 packet, bpw;
576
577	/* data packet should not exceed 1/2 of fifo space */
578	packet = clamp(xfer_len, 1U, spi->fifo_size / 2);
579
580	/* align packet size with data registers access */
581	bpw = DIV_ROUND_UP(spi->cur_bpw, 8);
582	return DIV_ROUND_UP(packet, bpw);
583}
584
585/**
586 * stm32f4_spi_write_tx - Write bytes to Transmit Data Register
587 * @spi: pointer to the spi controller data structure
588 *
589 * Read from tx_buf depends on remaining bytes to avoid to read beyond
590 * tx_buf end.
591 */
592static void stm32f4_spi_write_tx(struct stm32_spi *spi)
593{
594	if ((spi->tx_len > 0) && (readl_relaxed(spi->base + STM32FX_SPI_SR) &
595				  STM32FX_SPI_SR_TXE)) {
596		u32 offs = spi->cur_xferlen - spi->tx_len;
597
598		if (spi->cur_bpw == 16) {
599			const u16 *tx_buf16 = (const u16 *)(spi->tx_buf + offs);
600
601			writew_relaxed(*tx_buf16, spi->base + STM32FX_SPI_DR);
602			spi->tx_len -= sizeof(u16);
603		} else {
604			const u8 *tx_buf8 = (const u8 *)(spi->tx_buf + offs);
605
606			writeb_relaxed(*tx_buf8, spi->base + STM32FX_SPI_DR);
607			spi->tx_len -= sizeof(u8);
608		}
609	}
610
611	dev_dbg(spi->dev, "%s: %d bytes left\n", __func__, spi->tx_len);
612}
613
614/**
615 * stm32f7_spi_write_tx - Write bytes to Transmit Data Register
616 * @spi: pointer to the spi controller data structure
617 *
618 * Read from tx_buf depends on remaining bytes to avoid to read beyond
619 * tx_buf end.
620 */
621static void stm32f7_spi_write_tx(struct stm32_spi *spi)
622{
623	if ((spi->tx_len > 0) && (readl_relaxed(spi->base + STM32FX_SPI_SR) &
624				  STM32FX_SPI_SR_TXE)) {
625		u32 offs = spi->cur_xferlen - spi->tx_len;
626
627		if (spi->tx_len >= sizeof(u16)) {
628			const u16 *tx_buf16 = (const u16 *)(spi->tx_buf + offs);
629
630			writew_relaxed(*tx_buf16, spi->base + STM32FX_SPI_DR);
631			spi->tx_len -= sizeof(u16);
632		} else {
633			const u8 *tx_buf8 = (const u8 *)(spi->tx_buf + offs);
634
635			writeb_relaxed(*tx_buf8, spi->base + STM32FX_SPI_DR);
636			spi->tx_len -= sizeof(u8);
637		}
638	}
639
640	dev_dbg(spi->dev, "%s: %d bytes left\n", __func__, spi->tx_len);
641}
642
643/**
644 * stm32h7_spi_write_txfifo - Write bytes in Transmit Data Register
645 * @spi: pointer to the spi controller data structure
646 *
647 * Read from tx_buf depends on remaining bytes to avoid to read beyond
648 * tx_buf end.
649 */
650static void stm32h7_spi_write_txfifo(struct stm32_spi *spi)
651{
652	while ((spi->tx_len > 0) &&
653		       (readl_relaxed(spi->base + STM32H7_SPI_SR) &
654			STM32H7_SPI_SR_TXP)) {
655		u32 offs = spi->cur_xferlen - spi->tx_len;
656
657		if (spi->tx_len >= sizeof(u32)) {
658			const u32 *tx_buf32 = (const u32 *)(spi->tx_buf + offs);
659
660			writel_relaxed(*tx_buf32, spi->base + STM32H7_SPI_TXDR);
661			spi->tx_len -= sizeof(u32);
662		} else if (spi->tx_len >= sizeof(u16)) {
663			const u16 *tx_buf16 = (const u16 *)(spi->tx_buf + offs);
664
665			writew_relaxed(*tx_buf16, spi->base + STM32H7_SPI_TXDR);
666			spi->tx_len -= sizeof(u16);
667		} else {
668			const u8 *tx_buf8 = (const u8 *)(spi->tx_buf + offs);
669
670			writeb_relaxed(*tx_buf8, spi->base + STM32H7_SPI_TXDR);
671			spi->tx_len -= sizeof(u8);
672		}
673	}
674
675	dev_dbg(spi->dev, "%s: %d bytes left\n", __func__, spi->tx_len);
676}
677
678/**
679 * stm32f4_spi_read_rx - Read bytes from Receive Data Register
680 * @spi: pointer to the spi controller data structure
681 *
682 * Write in rx_buf depends on remaining bytes to avoid to write beyond
683 * rx_buf end.
684 */
685static void stm32f4_spi_read_rx(struct stm32_spi *spi)
686{
687	if ((spi->rx_len > 0) && (readl_relaxed(spi->base + STM32FX_SPI_SR) &
688				  STM32FX_SPI_SR_RXNE)) {
689		u32 offs = spi->cur_xferlen - spi->rx_len;
690
691		if (spi->cur_bpw == 16) {
692			u16 *rx_buf16 = (u16 *)(spi->rx_buf + offs);
693
694			*rx_buf16 = readw_relaxed(spi->base + STM32FX_SPI_DR);
695			spi->rx_len -= sizeof(u16);
696		} else {
697			u8 *rx_buf8 = (u8 *)(spi->rx_buf + offs);
698
699			*rx_buf8 = readb_relaxed(spi->base + STM32FX_SPI_DR);
700			spi->rx_len -= sizeof(u8);
701		}
702	}
703
704	dev_dbg(spi->dev, "%s: %d bytes left\n", __func__, spi->rx_len);
705}
706
707/**
708 * stm32f7_spi_read_rx - Read bytes from Receive Data Register
709 * @spi: pointer to the spi controller data structure
710 *
711 * Write in rx_buf depends on remaining bytes to avoid to write beyond
712 * rx_buf end.
713 */
714static void stm32f7_spi_read_rx(struct stm32_spi *spi)
715{
716	u32 sr = readl_relaxed(spi->base + STM32FX_SPI_SR);
717	u32 frlvl = FIELD_GET(STM32F7_SPI_SR_FRLVL, sr);
718
719	while ((spi->rx_len > 0) && (frlvl > 0)) {
720		u32 offs = spi->cur_xferlen - spi->rx_len;
721
722		if ((spi->rx_len >= sizeof(u16)) && (frlvl >= 2)) {
723			u16 *rx_buf16 = (u16 *)(spi->rx_buf + offs);
724
725			*rx_buf16 = readw_relaxed(spi->base + STM32FX_SPI_DR);
726			spi->rx_len -= sizeof(u16);
727		} else {
728			u8 *rx_buf8 = (u8 *)(spi->rx_buf + offs);
729
730			*rx_buf8 = readb_relaxed(spi->base + STM32FX_SPI_DR);
731			spi->rx_len -= sizeof(u8);
732		}
733
734		sr = readl_relaxed(spi->base + STM32FX_SPI_SR);
735		frlvl = FIELD_GET(STM32F7_SPI_SR_FRLVL, sr);
736	}
737
738	if (spi->rx_len >= sizeof(u16))
739		stm32_spi_clr_bits(spi, STM32FX_SPI_CR2, STM32F7_SPI_CR2_FRXTH);
740	else
741		stm32_spi_set_bits(spi, STM32FX_SPI_CR2, STM32F7_SPI_CR2_FRXTH);
742
743	dev_dbg(spi->dev, "%s: %d bytes left (sr=%08x)\n",
744		__func__, spi->rx_len, sr);
745}
746
747/**
748 * stm32h7_spi_read_rxfifo - Read bytes in Receive Data Register
749 * @spi: pointer to the spi controller data structure
750 *
751 * Write in rx_buf depends on remaining bytes to avoid to write beyond
752 * rx_buf end.
753 */
754static void stm32h7_spi_read_rxfifo(struct stm32_spi *spi)
755{
756	u32 sr = readl_relaxed(spi->base + STM32H7_SPI_SR);
757	u32 rxplvl = FIELD_GET(STM32H7_SPI_SR_RXPLVL, sr);
758
759	while ((spi->rx_len > 0) &&
760	       ((sr & STM32H7_SPI_SR_RXP) ||
761		((sr & STM32H7_SPI_SR_EOT) &&
762		 ((sr & STM32H7_SPI_SR_RXWNE) || (rxplvl > 0))))) {
763		u32 offs = spi->cur_xferlen - spi->rx_len;
764
765		if ((spi->rx_len >= sizeof(u32)) ||
766		    (sr & STM32H7_SPI_SR_RXWNE)) {
767			u32 *rx_buf32 = (u32 *)(spi->rx_buf + offs);
768
769			*rx_buf32 = readl_relaxed(spi->base + STM32H7_SPI_RXDR);
770			spi->rx_len -= sizeof(u32);
771		} else if ((spi->rx_len >= sizeof(u16)) ||
772			   (!(sr & STM32H7_SPI_SR_RXWNE) &&
773			    (rxplvl >= 2 || spi->cur_bpw > 8))) {
774			u16 *rx_buf16 = (u16 *)(spi->rx_buf + offs);
775
776			*rx_buf16 = readw_relaxed(spi->base + STM32H7_SPI_RXDR);
777			spi->rx_len -= sizeof(u16);
778		} else {
779			u8 *rx_buf8 = (u8 *)(spi->rx_buf + offs);
780
781			*rx_buf8 = readb_relaxed(spi->base + STM32H7_SPI_RXDR);
782			spi->rx_len -= sizeof(u8);
783		}
784
785		sr = readl_relaxed(spi->base + STM32H7_SPI_SR);
786		rxplvl = FIELD_GET(STM32H7_SPI_SR_RXPLVL, sr);
787	}
788
789	dev_dbg(spi->dev, "%s: %d bytes left (sr=%08x)\n",
790		__func__, spi->rx_len, sr);
791}
792
793/**
794 * stm32_spi_enable - Enable SPI controller
795 * @spi: pointer to the spi controller data structure
796 */
797static void stm32_spi_enable(struct stm32_spi *spi)
798{
799	dev_dbg(spi->dev, "enable controller\n");
800
801	stm32_spi_set_bits(spi, spi->cfg->regs->en.reg,
802			   spi->cfg->regs->en.mask);
803}
804
805/**
806 * stm32fx_spi_disable - Disable SPI controller
807 * @spi: pointer to the spi controller data structure
808 */
809static void stm32fx_spi_disable(struct stm32_spi *spi)
810{
811	unsigned long flags;
812	u32 sr;
813
814	dev_dbg(spi->dev, "disable controller\n");
815
816	spin_lock_irqsave(&spi->lock, flags);
817
818	if (!(readl_relaxed(spi->base + STM32FX_SPI_CR1) &
819	      STM32FX_SPI_CR1_SPE)) {
820		spin_unlock_irqrestore(&spi->lock, flags);
821		return;
822	}
823
824	/* Disable interrupts */
825	stm32_spi_clr_bits(spi, STM32FX_SPI_CR2, STM32FX_SPI_CR2_TXEIE |
826						 STM32FX_SPI_CR2_RXNEIE |
827						 STM32FX_SPI_CR2_ERRIE);
828
829	/* Wait until BSY = 0 */
830	if (readl_relaxed_poll_timeout_atomic(spi->base + STM32FX_SPI_SR,
831					      sr, !(sr & STM32FX_SPI_SR_BSY),
832					      10, 100000) < 0) {
833		dev_warn(spi->dev, "disabling condition timeout\n");
834	}
835
836	if (spi->cur_usedma && spi->dma_tx)
837		dmaengine_terminate_async(spi->dma_tx);
838	if (spi->cur_usedma && spi->dma_rx)
839		dmaengine_terminate_async(spi->dma_rx);
840
841	stm32_spi_clr_bits(spi, STM32FX_SPI_CR1, STM32FX_SPI_CR1_SPE);
842
843	stm32_spi_clr_bits(spi, STM32FX_SPI_CR2, STM32FX_SPI_CR2_TXDMAEN |
844						 STM32FX_SPI_CR2_RXDMAEN);
845
846	/* Sequence to clear OVR flag */
847	readl_relaxed(spi->base + STM32FX_SPI_DR);
848	readl_relaxed(spi->base + STM32FX_SPI_SR);
849
850	spin_unlock_irqrestore(&spi->lock, flags);
851}
852
853/**
854 * stm32h7_spi_disable - Disable SPI controller
855 * @spi: pointer to the spi controller data structure
856 *
857 * RX-Fifo is flushed when SPI controller is disabled.
858 */
859static void stm32h7_spi_disable(struct stm32_spi *spi)
860{
861	unsigned long flags;
862	u32 cr1;
863
864	dev_dbg(spi->dev, "disable controller\n");
865
866	spin_lock_irqsave(&spi->lock, flags);
867
868	cr1 = readl_relaxed(spi->base + STM32H7_SPI_CR1);
869
870	if (!(cr1 & STM32H7_SPI_CR1_SPE)) {
871		spin_unlock_irqrestore(&spi->lock, flags);
872		return;
873	}
874
875	/* Add a delay to make sure that transmission is ended. */
876	if (spi->cur_half_period)
877		udelay(spi->cur_half_period);
878
879	if (spi->cur_usedma && spi->dma_tx)
880		dmaengine_terminate_async(spi->dma_tx);
881	if (spi->cur_usedma && spi->dma_rx)
882		dmaengine_terminate_async(spi->dma_rx);
883
884	stm32_spi_clr_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_SPE);
885
886	stm32_spi_clr_bits(spi, STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_TXDMAEN |
887						STM32H7_SPI_CFG1_RXDMAEN);
888
889	/* Disable interrupts and clear status flags */
890	writel_relaxed(0, spi->base + STM32H7_SPI_IER);
891	writel_relaxed(STM32H7_SPI_IFCR_ALL, spi->base + STM32H7_SPI_IFCR);
892
893	spin_unlock_irqrestore(&spi->lock, flags);
894}
895
896/**
897 * stm32_spi_can_dma - Determine if the transfer is eligible for DMA use
898 * @ctrl: controller interface
899 * @spi_dev: pointer to the spi device
900 * @transfer: pointer to spi transfer
901 *
902 * If driver has fifo and the current transfer size is greater than fifo size,
903 * use DMA. Otherwise use DMA for transfer longer than defined DMA min bytes.
904 */
905static bool stm32_spi_can_dma(struct spi_controller *ctrl,
906			      struct spi_device *spi_dev,
907			      struct spi_transfer *transfer)
908{
909	unsigned int dma_size;
910	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
911
912	if (spi->cfg->has_fifo)
913		dma_size = spi->fifo_size;
914	else
915		dma_size = SPI_DMA_MIN_BYTES;
916
917	dev_dbg(spi->dev, "%s: %s\n", __func__,
918		(transfer->len > dma_size) ? "true" : "false");
919
920	return (transfer->len > dma_size);
921}
922
923/**
924 * stm32fx_spi_irq_event - Interrupt handler for SPI controller events
925 * @irq: interrupt line
926 * @dev_id: SPI controller ctrl interface
927 */
928static irqreturn_t stm32fx_spi_irq_event(int irq, void *dev_id)
929{
930	struct spi_controller *ctrl = dev_id;
931	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
932	u32 sr, mask = 0;
933	bool end = false;
934
935	spin_lock(&spi->lock);
936
937	sr = readl_relaxed(spi->base + STM32FX_SPI_SR);
938	/*
939	 * BSY flag is not handled in interrupt but it is normal behavior when
940	 * this flag is set.
941	 */
942	sr &= ~STM32FX_SPI_SR_BSY;
943
944	if (!spi->cur_usedma && (spi->cur_comm == SPI_SIMPLEX_TX ||
945				 spi->cur_comm == SPI_3WIRE_TX)) {
946		/* OVR flag shouldn't be handled for TX only mode */
947		sr &= ~(STM32FX_SPI_SR_OVR | STM32FX_SPI_SR_RXNE);
948		mask |= STM32FX_SPI_SR_TXE;
949	}
950
951	if (!spi->cur_usedma && (spi->cur_comm == SPI_FULL_DUPLEX ||
952				spi->cur_comm == SPI_SIMPLEX_RX ||
953				spi->cur_comm == SPI_3WIRE_RX)) {
954		/* TXE flag is set and is handled when RXNE flag occurs */
955		sr &= ~STM32FX_SPI_SR_TXE;
956		mask |= STM32FX_SPI_SR_RXNE | STM32FX_SPI_SR_OVR;
957	}
958
959	if (!(sr & mask)) {
960		dev_dbg(spi->dev, "spurious IT (sr=0x%08x)\n", sr);
961		spin_unlock(&spi->lock);
962		return IRQ_NONE;
963	}
964
965	if (sr & STM32FX_SPI_SR_OVR) {
966		dev_warn(spi->dev, "Overrun: received value discarded\n");
967
968		/* Sequence to clear OVR flag */
969		readl_relaxed(spi->base + STM32FX_SPI_DR);
970		readl_relaxed(spi->base + STM32FX_SPI_SR);
971
972		/*
973		 * If overrun is detected, it means that something went wrong,
974		 * so stop the current transfer. Transfer can wait for next
975		 * RXNE but DR is already read and end never happens.
976		 */
977		end = true;
978		goto end_irq;
979	}
980
981	if (sr & STM32FX_SPI_SR_TXE) {
982		if (spi->tx_buf)
983			spi->cfg->write_tx(spi);
984		if (spi->tx_len == 0)
985			end = true;
986	}
987
988	if (sr & STM32FX_SPI_SR_RXNE) {
989		spi->cfg->read_rx(spi);
990		if (spi->rx_len == 0)
991			end = true;
992		else if (spi->tx_buf)/* Load data for discontinuous mode */
993			spi->cfg->write_tx(spi);
994	}
995
996end_irq:
997	if (end) {
998		/* Immediately disable interrupts to do not generate new one */
999		stm32_spi_clr_bits(spi, STM32FX_SPI_CR2,
1000					STM32FX_SPI_CR2_TXEIE |
1001					STM32FX_SPI_CR2_RXNEIE |
1002					STM32FX_SPI_CR2_ERRIE);
1003		spin_unlock(&spi->lock);
1004		return IRQ_WAKE_THREAD;
1005	}
1006
1007	spin_unlock(&spi->lock);
1008	return IRQ_HANDLED;
1009}
1010
1011/**
1012 * stm32fx_spi_irq_thread - Thread of interrupt handler for SPI controller
1013 * @irq: interrupt line
1014 * @dev_id: SPI controller interface
1015 */
1016static irqreturn_t stm32fx_spi_irq_thread(int irq, void *dev_id)
1017{
1018	struct spi_controller *ctrl = dev_id;
1019	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
1020
1021	spi_finalize_current_transfer(ctrl);
1022	stm32fx_spi_disable(spi);
1023
1024	return IRQ_HANDLED;
1025}
1026
1027/**
1028 * stm32h7_spi_irq_thread - Thread of interrupt handler for SPI controller
1029 * @irq: interrupt line
1030 * @dev_id: SPI controller interface
1031 */
1032static irqreturn_t stm32h7_spi_irq_thread(int irq, void *dev_id)
1033{
1034	struct spi_controller *ctrl = dev_id;
1035	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
1036	u32 sr, ier, mask;
1037	unsigned long flags;
1038	bool end = false;
1039
1040	spin_lock_irqsave(&spi->lock, flags);
1041
1042	sr = readl_relaxed(spi->base + STM32H7_SPI_SR);
1043	ier = readl_relaxed(spi->base + STM32H7_SPI_IER);
1044
1045	mask = ier;
1046	/*
1047	 * EOTIE enables irq from EOT, SUSP and TXC events. We need to set
1048	 * SUSP to acknowledge it later. TXC is automatically cleared
1049	 */
1050
1051	mask |= STM32H7_SPI_SR_SUSP;
1052	/*
1053	 * DXPIE is set in Full-Duplex, one IT will be raised if TXP and RXP
1054	 * are set. So in case of Full-Duplex, need to poll TXP and RXP event.
1055	 */
1056	if ((spi->cur_comm == SPI_FULL_DUPLEX) && !spi->cur_usedma)
1057		mask |= STM32H7_SPI_SR_TXP | STM32H7_SPI_SR_RXP;
1058
1059	if (!(sr & mask)) {
1060		dev_warn(spi->dev, "spurious IT (sr=0x%08x, ier=0x%08x)\n",
1061			 sr, ier);
1062		spin_unlock_irqrestore(&spi->lock, flags);
1063		return IRQ_NONE;
1064	}
1065
1066	if (sr & STM32H7_SPI_SR_SUSP) {
1067		static DEFINE_RATELIMIT_STATE(rs,
1068					      DEFAULT_RATELIMIT_INTERVAL * 10,
1069					      1);
1070		ratelimit_set_flags(&rs, RATELIMIT_MSG_ON_RELEASE);
1071		if (__ratelimit(&rs))
1072			dev_dbg_ratelimited(spi->dev, "Communication suspended\n");
1073		if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0)))
1074			stm32h7_spi_read_rxfifo(spi);
1075		/*
1076		 * If communication is suspended while using DMA, it means
1077		 * that something went wrong, so stop the current transfer
1078		 */
1079		if (spi->cur_usedma)
1080			end = true;
1081	}
1082
1083	if (sr & STM32H7_SPI_SR_MODF) {
1084		dev_warn(spi->dev, "Mode fault: transfer aborted\n");
1085		end = true;
1086	}
1087
1088	if (sr & STM32H7_SPI_SR_OVR) {
1089		dev_err(spi->dev, "Overrun: RX data lost\n");
1090		end = true;
1091	}
1092
1093	if (sr & STM32H7_SPI_SR_EOT) {
1094		if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0)))
1095			stm32h7_spi_read_rxfifo(spi);
1096		if (!spi->cur_usedma ||
1097		    (spi->cur_comm == SPI_SIMPLEX_TX || spi->cur_comm == SPI_3WIRE_TX))
1098			end = true;
1099	}
1100
1101	if (sr & STM32H7_SPI_SR_TXP)
1102		if (!spi->cur_usedma && (spi->tx_buf && (spi->tx_len > 0)))
1103			stm32h7_spi_write_txfifo(spi);
1104
1105	if (sr & STM32H7_SPI_SR_RXP)
1106		if (!spi->cur_usedma && (spi->rx_buf && (spi->rx_len > 0)))
1107			stm32h7_spi_read_rxfifo(spi);
1108
1109	writel_relaxed(sr & mask, spi->base + STM32H7_SPI_IFCR);
1110
1111	spin_unlock_irqrestore(&spi->lock, flags);
1112
1113	if (end) {
1114		stm32h7_spi_disable(spi);
1115		spi_finalize_current_transfer(ctrl);
1116	}
1117
1118	return IRQ_HANDLED;
1119}
1120
1121static int stm32_spi_optimize_message(struct spi_message *msg)
1122{
1123	struct spi_controller *ctrl = msg->spi->controller;
1124	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
1125
1126	/* On STM32H7, messages should not exceed a maximum size set
1127	 * later via the set_number_of_data function. In order to
1128	 * ensure that, split large messages into several messages
1129	 */
1130	if (spi->cfg->set_number_of_data)
1131		return spi_split_transfers_maxwords(ctrl, msg, spi->t_size_max);
1132
1133	return 0;
1134}
1135
1136/**
1137 * stm32_spi_prepare_msg - set up the controller to transfer a single message
1138 * @ctrl: controller interface
1139 * @msg: pointer to spi message
1140 */
1141static int stm32_spi_prepare_msg(struct spi_controller *ctrl,
1142				 struct spi_message *msg)
1143{
1144	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
1145	struct spi_device *spi_dev = msg->spi;
1146	struct device_node *np = spi_dev->dev.of_node;
1147	unsigned long flags;
1148	u32 clrb = 0, setb = 0;
1149
1150	/* SPI target device may need time between data frames */
1151	spi->cur_midi = 0;
1152	if (np && !of_property_read_u32(np, "st,spi-midi-ns", &spi->cur_midi))
1153		dev_dbg(spi->dev, "%dns inter-data idleness\n", spi->cur_midi);
1154
1155	if (spi_dev->mode & SPI_CPOL)
1156		setb |= spi->cfg->regs->cpol.mask;
1157	else
1158		clrb |= spi->cfg->regs->cpol.mask;
1159
1160	if (spi_dev->mode & SPI_CPHA)
1161		setb |= spi->cfg->regs->cpha.mask;
1162	else
1163		clrb |= spi->cfg->regs->cpha.mask;
1164
1165	if (spi_dev->mode & SPI_LSB_FIRST)
1166		setb |= spi->cfg->regs->lsb_first.mask;
1167	else
1168		clrb |= spi->cfg->regs->lsb_first.mask;
1169
1170	if (STM32_SPI_DEVICE_MODE(spi) && spi_dev->mode & SPI_CS_HIGH)
1171		setb |= spi->cfg->regs->cs_high.mask;
1172	else
1173		clrb |= spi->cfg->regs->cs_high.mask;
1174
1175	dev_dbg(spi->dev, "cpol=%d cpha=%d lsb_first=%d cs_high=%d\n",
1176		!!(spi_dev->mode & SPI_CPOL),
1177		!!(spi_dev->mode & SPI_CPHA),
1178		!!(spi_dev->mode & SPI_LSB_FIRST),
1179		!!(spi_dev->mode & SPI_CS_HIGH));
1180
1181	spin_lock_irqsave(&spi->lock, flags);
1182
1183	/* CPOL, CPHA and LSB FIRST bits have common register */
1184	if (clrb || setb)
1185		writel_relaxed(
1186			(readl_relaxed(spi->base + spi->cfg->regs->cpol.reg) &
1187			 ~clrb) | setb,
1188			spi->base + spi->cfg->regs->cpol.reg);
1189
1190	spin_unlock_irqrestore(&spi->lock, flags);
1191
1192	return 0;
1193}
1194
1195/**
1196 * stm32fx_spi_dma_tx_cb - dma callback
1197 * @data: pointer to the spi controller data structure
1198 *
1199 * DMA callback is called when the transfer is complete for DMA TX channel.
1200 */
1201static void stm32fx_spi_dma_tx_cb(void *data)
1202{
1203	struct stm32_spi *spi = data;
1204
1205	if (spi->cur_comm == SPI_SIMPLEX_TX || spi->cur_comm == SPI_3WIRE_TX) {
1206		spi_finalize_current_transfer(spi->ctrl);
1207		stm32fx_spi_disable(spi);
1208	}
1209}
1210
1211/**
1212 * stm32_spi_dma_rx_cb - dma callback
1213 * @data: pointer to the spi controller data structure
1214 *
1215 * DMA callback is called when the transfer is complete for DMA RX channel.
1216 */
1217static void stm32_spi_dma_rx_cb(void *data)
1218{
1219	struct stm32_spi *spi = data;
1220
1221	spi_finalize_current_transfer(spi->ctrl);
1222	spi->cfg->disable(spi);
1223}
1224
1225/**
1226 * stm32_spi_dma_config - configure dma slave channel depending on current
1227 *			  transfer bits_per_word.
1228 * @spi: pointer to the spi controller data structure
1229 * @dma_chan: pointer to the DMA channel
1230 * @dma_conf: pointer to the dma_slave_config structure
1231 * @dir: direction of the dma transfer
1232 */
1233static void stm32_spi_dma_config(struct stm32_spi *spi,
1234				 struct dma_chan *dma_chan,
1235				 struct dma_slave_config *dma_conf,
1236				 enum dma_transfer_direction dir)
1237{
1238	enum dma_slave_buswidth buswidth;
1239	struct dma_slave_caps caps;
1240	u32 maxburst = 1;
1241	int ret;
1242
1243	if (spi->cur_bpw <= 8)
1244		buswidth = DMA_SLAVE_BUSWIDTH_1_BYTE;
1245	else if (spi->cur_bpw <= 16)
1246		buswidth = DMA_SLAVE_BUSWIDTH_2_BYTES;
1247	else
1248		buswidth = DMA_SLAVE_BUSWIDTH_4_BYTES;
1249
1250	/* Valid for DMA Half or Full Fifo threshold */
1251	if (!spi->cfg->prevent_dma_burst && spi->cfg->has_fifo && spi->cur_fthlv != 2)
1252		maxburst = spi->cur_fthlv;
1253
1254	/* Get the DMA channel caps, and adjust maxburst if possible */
1255	ret = dma_get_slave_caps(dma_chan, &caps);
1256	if (!ret)
1257		maxburst = min(maxburst, caps.max_burst);
1258
1259	memset(dma_conf, 0, sizeof(struct dma_slave_config));
1260	dma_conf->direction = dir;
1261	if (dma_conf->direction == DMA_DEV_TO_MEM) { /* RX */
1262		dma_conf->src_addr = spi->phys_addr + spi->cfg->regs->rx.reg;
1263		dma_conf->src_addr_width = buswidth;
1264		dma_conf->src_maxburst = maxburst;
1265
1266		dev_dbg(spi->dev, "Rx DMA config buswidth=%d, maxburst=%d\n",
1267			buswidth, maxburst);
1268	} else if (dma_conf->direction == DMA_MEM_TO_DEV) { /* TX */
1269		dma_conf->dst_addr = spi->phys_addr + spi->cfg->regs->tx.reg;
1270		dma_conf->dst_addr_width = buswidth;
1271		dma_conf->dst_maxburst = maxburst;
1272
1273		dev_dbg(spi->dev, "Tx DMA config buswidth=%d, maxburst=%d\n",
1274			buswidth, maxburst);
1275	}
1276}
1277
1278/**
1279 * stm32fx_spi_transfer_one_irq - transfer a single spi_transfer using
1280 *				  interrupts
1281 * @spi: pointer to the spi controller data structure
1282 *
1283 * It must returns 0 if the transfer is finished or 1 if the transfer is still
1284 * in progress.
1285 */
1286static int stm32fx_spi_transfer_one_irq(struct stm32_spi *spi)
1287{
1288	unsigned long flags;
1289	u32 cr2 = 0;
1290
1291	/* Enable the interrupts relative to the current communication mode */
1292	if (spi->cur_comm == SPI_SIMPLEX_TX || spi->cur_comm == SPI_3WIRE_TX) {
1293		cr2 |= STM32FX_SPI_CR2_TXEIE;
1294	} else if (spi->cur_comm == SPI_FULL_DUPLEX ||
1295				spi->cur_comm == SPI_SIMPLEX_RX ||
1296				spi->cur_comm == SPI_3WIRE_RX) {
1297		/* In transmit-only mode, the OVR flag is set in the SR register
1298		 * since the received data are never read. Therefore set OVR
1299		 * interrupt only when rx buffer is available.
1300		 */
1301		cr2 |= STM32FX_SPI_CR2_RXNEIE | STM32FX_SPI_CR2_ERRIE;
1302	} else {
1303		return -EINVAL;
1304	}
1305
1306	spin_lock_irqsave(&spi->lock, flags);
1307
1308	stm32_spi_set_bits(spi, STM32FX_SPI_CR2, cr2);
1309
1310	stm32_spi_enable(spi);
1311
1312	/* starting data transfer when buffer is loaded */
1313	if (spi->tx_buf)
1314		spi->cfg->write_tx(spi);
1315
1316	spin_unlock_irqrestore(&spi->lock, flags);
1317
1318	return 1;
1319}
1320
1321/**
1322 * stm32h7_spi_transfer_one_irq - transfer a single spi_transfer using
1323 *				  interrupts
1324 * @spi: pointer to the spi controller data structure
1325 *
1326 * It must returns 0 if the transfer is finished or 1 if the transfer is still
1327 * in progress.
1328 */
1329static int stm32h7_spi_transfer_one_irq(struct stm32_spi *spi)
1330{
1331	unsigned long flags;
1332	u32 ier = 0;
1333
1334	/* Enable the interrupts relative to the current communication mode */
1335	if (spi->tx_buf && spi->rx_buf)	/* Full Duplex */
1336		ier |= STM32H7_SPI_IER_DXPIE;
1337	else if (spi->tx_buf)		/* Half-Duplex TX dir or Simplex TX */
1338		ier |= STM32H7_SPI_IER_TXPIE;
1339	else if (spi->rx_buf)		/* Half-Duplex RX dir or Simplex RX */
1340		ier |= STM32H7_SPI_IER_RXPIE;
1341
1342	/* Enable the interrupts relative to the end of transfer */
1343	ier |= STM32H7_SPI_IER_EOTIE | STM32H7_SPI_IER_TXTFIE |
1344	       STM32H7_SPI_IER_OVRIE | STM32H7_SPI_IER_MODFIE;
1345
1346	spin_lock_irqsave(&spi->lock, flags);
1347
1348	stm32_spi_enable(spi);
1349
1350	/* Be sure to have data in fifo before starting data transfer */
1351	if (spi->tx_buf)
1352		stm32h7_spi_write_txfifo(spi);
1353
1354	if (STM32_SPI_HOST_MODE(spi))
1355		stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART);
1356
1357	writel_relaxed(ier, spi->base + STM32H7_SPI_IER);
1358
1359	spin_unlock_irqrestore(&spi->lock, flags);
1360
1361	return 1;
1362}
1363
1364/**
1365 * stm32fx_spi_transfer_one_dma_start - Set SPI driver registers to start
1366 *					transfer using DMA
1367 * @spi: pointer to the spi controller data structure
1368 */
1369static void stm32fx_spi_transfer_one_dma_start(struct stm32_spi *spi)
1370{
1371	/* In DMA mode end of transfer is handled by DMA TX or RX callback. */
1372	if (spi->cur_comm == SPI_SIMPLEX_RX || spi->cur_comm == SPI_3WIRE_RX ||
1373	    spi->cur_comm == SPI_FULL_DUPLEX) {
1374		/*
1375		 * In transmit-only mode, the OVR flag is set in the SR register
1376		 * since the received data are never read. Therefore set OVR
1377		 * interrupt only when rx buffer is available.
1378		 */
1379		stm32_spi_set_bits(spi, STM32FX_SPI_CR2, STM32FX_SPI_CR2_ERRIE);
1380	}
1381
1382	stm32_spi_enable(spi);
1383}
1384
1385/**
1386 * stm32f7_spi_transfer_one_dma_start - Set SPI driver registers to start
1387 *					transfer using DMA
1388 * @spi: pointer to the spi controller data structure
1389 */
1390static void stm32f7_spi_transfer_one_dma_start(struct stm32_spi *spi)
1391{
1392	/* Configure DMA request trigger threshold according to DMA width */
1393	if (spi->cur_bpw <= 8)
1394		stm32_spi_set_bits(spi, STM32FX_SPI_CR2, STM32F7_SPI_CR2_FRXTH);
1395	else
1396		stm32_spi_clr_bits(spi, STM32FX_SPI_CR2, STM32F7_SPI_CR2_FRXTH);
1397
1398	stm32fx_spi_transfer_one_dma_start(spi);
1399}
1400
1401/**
1402 * stm32h7_spi_transfer_one_dma_start - Set SPI driver registers to start
1403 *					transfer using DMA
1404 * @spi: pointer to the spi controller data structure
1405 */
1406static void stm32h7_spi_transfer_one_dma_start(struct stm32_spi *spi)
1407{
1408	uint32_t ier = STM32H7_SPI_IER_OVRIE | STM32H7_SPI_IER_MODFIE;
1409
1410	/* Enable the interrupts */
1411	if (spi->cur_comm == SPI_SIMPLEX_TX || spi->cur_comm == SPI_3WIRE_TX)
1412		ier |= STM32H7_SPI_IER_EOTIE | STM32H7_SPI_IER_TXTFIE;
1413
1414	stm32_spi_set_bits(spi, STM32H7_SPI_IER, ier);
1415
1416	stm32_spi_enable(spi);
1417
1418	if (STM32_SPI_HOST_MODE(spi))
1419		stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART);
1420}
1421
1422/**
1423 * stm32_spi_transfer_one_dma - transfer a single spi_transfer using DMA
1424 * @spi: pointer to the spi controller data structure
1425 * @xfer: pointer to the spi_transfer structure
1426 *
1427 * It must returns 0 if the transfer is finished or 1 if the transfer is still
1428 * in progress.
1429 */
1430static int stm32_spi_transfer_one_dma(struct stm32_spi *spi,
1431				      struct spi_transfer *xfer)
1432{
1433	struct dma_slave_config tx_dma_conf, rx_dma_conf;
1434	struct dma_async_tx_descriptor *tx_dma_desc, *rx_dma_desc;
1435	unsigned long flags;
1436
1437	spin_lock_irqsave(&spi->lock, flags);
1438
1439	rx_dma_desc = NULL;
1440	if (spi->rx_buf && spi->dma_rx) {
1441		stm32_spi_dma_config(spi, spi->dma_rx, &rx_dma_conf, DMA_DEV_TO_MEM);
1442		dmaengine_slave_config(spi->dma_rx, &rx_dma_conf);
1443
1444		/* Enable Rx DMA request */
1445		stm32_spi_set_bits(spi, spi->cfg->regs->dma_rx_en.reg,
1446				   spi->cfg->regs->dma_rx_en.mask);
1447
1448		rx_dma_desc = dmaengine_prep_slave_sg(
1449					spi->dma_rx, xfer->rx_sg.sgl,
1450					xfer->rx_sg.nents,
1451					rx_dma_conf.direction,
1452					DMA_PREP_INTERRUPT);
1453	}
1454
1455	tx_dma_desc = NULL;
1456	if (spi->tx_buf && spi->dma_tx) {
1457		stm32_spi_dma_config(spi, spi->dma_tx, &tx_dma_conf, DMA_MEM_TO_DEV);
1458		dmaengine_slave_config(spi->dma_tx, &tx_dma_conf);
1459
1460		tx_dma_desc = dmaengine_prep_slave_sg(
1461					spi->dma_tx, xfer->tx_sg.sgl,
1462					xfer->tx_sg.nents,
1463					tx_dma_conf.direction,
1464					DMA_PREP_INTERRUPT);
1465	}
1466
1467	if ((spi->tx_buf && spi->dma_tx && !tx_dma_desc) ||
1468	    (spi->rx_buf && spi->dma_rx && !rx_dma_desc))
1469		goto dma_desc_error;
1470
1471	if (spi->cur_comm == SPI_FULL_DUPLEX && (!tx_dma_desc || !rx_dma_desc))
1472		goto dma_desc_error;
1473
1474	if (rx_dma_desc) {
1475		rx_dma_desc->callback = spi->cfg->dma_rx_cb;
1476		rx_dma_desc->callback_param = spi;
1477
1478		if (dma_submit_error(dmaengine_submit(rx_dma_desc))) {
1479			dev_err(spi->dev, "Rx DMA submit failed\n");
1480			goto dma_desc_error;
1481		}
1482		/* Enable Rx DMA channel */
1483		dma_async_issue_pending(spi->dma_rx);
1484	}
1485
1486	if (tx_dma_desc) {
1487		if (spi->cur_comm == SPI_SIMPLEX_TX ||
1488		    spi->cur_comm == SPI_3WIRE_TX) {
1489			tx_dma_desc->callback = spi->cfg->dma_tx_cb;
1490			tx_dma_desc->callback_param = spi;
1491		}
1492
1493		if (dma_submit_error(dmaengine_submit(tx_dma_desc))) {
1494			dev_err(spi->dev, "Tx DMA submit failed\n");
1495			goto dma_submit_error;
1496		}
1497		/* Enable Tx DMA channel */
1498		dma_async_issue_pending(spi->dma_tx);
1499
1500		/* Enable Tx DMA request */
1501		stm32_spi_set_bits(spi, spi->cfg->regs->dma_tx_en.reg,
1502				   spi->cfg->regs->dma_tx_en.mask);
1503	}
1504
1505	spi->cfg->transfer_one_dma_start(spi);
1506
1507	spin_unlock_irqrestore(&spi->lock, flags);
1508
1509	return 1;
1510
1511dma_submit_error:
1512	if (spi->dma_rx)
1513		dmaengine_terminate_sync(spi->dma_rx);
1514
1515dma_desc_error:
1516	stm32_spi_clr_bits(spi, spi->cfg->regs->dma_rx_en.reg,
1517			   spi->cfg->regs->dma_rx_en.mask);
1518
1519	spin_unlock_irqrestore(&spi->lock, flags);
1520
1521	dev_info(spi->dev, "DMA issue: fall back to irq transfer\n");
1522
1523	spi->cur_usedma = false;
1524	return spi->cfg->transfer_one_irq(spi);
1525}
1526
1527/**
1528 * stm32f4_spi_set_bpw - Configure bits per word
1529 * @spi: pointer to the spi controller data structure
1530 */
1531static void stm32f4_spi_set_bpw(struct stm32_spi *spi)
1532{
1533	if (spi->cur_bpw == 16)
1534		stm32_spi_set_bits(spi, STM32FX_SPI_CR1, STM32F4_SPI_CR1_DFF);
1535	else
1536		stm32_spi_clr_bits(spi, STM32FX_SPI_CR1, STM32F4_SPI_CR1_DFF);
1537}
1538
1539/**
1540 * stm32f7_spi_set_bpw - Configure bits per word
1541 * @spi: pointer to the spi controller data structure
1542 */
1543static void stm32f7_spi_set_bpw(struct stm32_spi *spi)
1544{
1545	u32 bpw;
1546	u32 cr2_clrb = 0, cr2_setb = 0;
1547
1548	bpw = spi->cur_bpw - 1;
1549
1550	cr2_clrb |= STM32F7_SPI_CR2_DS;
1551	cr2_setb |= FIELD_PREP(STM32F7_SPI_CR2_DS, bpw);
1552
1553	if (spi->rx_len >= sizeof(u16))
1554		cr2_clrb |= STM32F7_SPI_CR2_FRXTH;
1555	else
1556		cr2_setb |= STM32F7_SPI_CR2_FRXTH;
1557
1558	writel_relaxed(
1559		(readl_relaxed(spi->base + STM32FX_SPI_CR2) &
1560		 ~cr2_clrb) | cr2_setb,
1561		spi->base + STM32FX_SPI_CR2);
1562}
1563
1564/**
1565 * stm32h7_spi_set_bpw - configure bits per word
1566 * @spi: pointer to the spi controller data structure
1567 */
1568static void stm32h7_spi_set_bpw(struct stm32_spi *spi)
1569{
1570	u32 bpw, fthlv;
1571	u32 cfg1_clrb = 0, cfg1_setb = 0;
1572
1573	bpw = spi->cur_bpw - 1;
1574
1575	cfg1_clrb |= STM32H7_SPI_CFG1_DSIZE;
1576	cfg1_setb |= FIELD_PREP(STM32H7_SPI_CFG1_DSIZE, bpw);
1577
1578	spi->cur_fthlv = stm32h7_spi_prepare_fthlv(spi, spi->cur_xferlen);
1579	fthlv = spi->cur_fthlv - 1;
1580
1581	cfg1_clrb |= STM32H7_SPI_CFG1_FTHLV;
1582	cfg1_setb |= FIELD_PREP(STM32H7_SPI_CFG1_FTHLV, fthlv);
1583
1584	writel_relaxed(
1585		(readl_relaxed(spi->base + STM32H7_SPI_CFG1) &
1586		 ~cfg1_clrb) | cfg1_setb,
1587		spi->base + STM32H7_SPI_CFG1);
1588}
1589
1590/**
1591 * stm32_spi_set_mbr - Configure baud rate divisor in host mode
1592 * @spi: pointer to the spi controller data structure
1593 * @mbrdiv: baud rate divisor value
1594 */
1595static void stm32_spi_set_mbr(struct stm32_spi *spi, u32 mbrdiv)
1596{
1597	u32 clrb = 0, setb = 0;
1598
1599	clrb |= spi->cfg->regs->br.mask;
1600	setb |= (mbrdiv << spi->cfg->regs->br.shift) & spi->cfg->regs->br.mask;
1601
1602	writel_relaxed((readl_relaxed(spi->base + spi->cfg->regs->br.reg) &
1603			~clrb) | setb,
1604		       spi->base + spi->cfg->regs->br.reg);
1605}
1606
1607/**
1608 * stm32_spi_communication_type - return transfer communication type
1609 * @spi_dev: pointer to the spi device
1610 * @transfer: pointer to spi transfer
1611 */
1612static unsigned int stm32_spi_communication_type(struct spi_device *spi_dev,
1613						 struct spi_transfer *transfer)
1614{
1615	unsigned int type = SPI_FULL_DUPLEX;
1616
1617	if (spi_dev->mode & SPI_3WIRE) { /* MISO/MOSI signals shared */
1618		/*
1619		 * SPI_3WIRE and xfer->tx_buf != NULL and xfer->rx_buf != NULL
1620		 * is forbidden and unvalidated by SPI subsystem so depending
1621		 * on the valid buffer, we can determine the direction of the
1622		 * transfer.
1623		 */
1624		if (!transfer->tx_buf)
1625			type = SPI_3WIRE_RX;
1626		else
1627			type = SPI_3WIRE_TX;
1628	} else {
1629		if (!transfer->tx_buf)
1630			type = SPI_SIMPLEX_RX;
1631		else if (!transfer->rx_buf)
1632			type = SPI_SIMPLEX_TX;
1633	}
1634
1635	return type;
1636}
1637
1638/**
1639 * stm32fx_spi_set_mode - configure communication mode
1640 * @spi: pointer to the spi controller data structure
1641 * @comm_type: type of communication to configure
1642 */
1643static int stm32fx_spi_set_mode(struct stm32_spi *spi, unsigned int comm_type)
1644{
1645	if (comm_type == SPI_3WIRE_TX || comm_type == SPI_SIMPLEX_TX) {
1646		stm32_spi_set_bits(spi, STM32FX_SPI_CR1,
1647					STM32FX_SPI_CR1_BIDIMODE |
1648					STM32FX_SPI_CR1_BIDIOE);
1649	} else if (comm_type == SPI_FULL_DUPLEX ||
1650				comm_type == SPI_SIMPLEX_RX) {
1651		stm32_spi_clr_bits(spi, STM32FX_SPI_CR1,
1652					STM32FX_SPI_CR1_BIDIMODE |
1653					STM32FX_SPI_CR1_BIDIOE);
1654	} else if (comm_type == SPI_3WIRE_RX) {
1655		stm32_spi_set_bits(spi, STM32FX_SPI_CR1,
1656					STM32FX_SPI_CR1_BIDIMODE);
1657		stm32_spi_clr_bits(spi, STM32FX_SPI_CR1,
1658					STM32FX_SPI_CR1_BIDIOE);
1659	} else {
1660		return -EINVAL;
1661	}
1662
1663	return 0;
1664}
1665
1666/**
1667 * stm32h7_spi_set_mode - configure communication mode
1668 * @spi: pointer to the spi controller data structure
1669 * @comm_type: type of communication to configure
1670 */
1671static int stm32h7_spi_set_mode(struct stm32_spi *spi, unsigned int comm_type)
1672{
1673	u32 mode;
1674	u32 cfg2_clrb = 0, cfg2_setb = 0;
1675
1676	if (comm_type == SPI_3WIRE_RX) {
1677		mode = STM32H7_SPI_HALF_DUPLEX;
1678		stm32_spi_clr_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_HDDIR);
1679	} else if (comm_type == SPI_3WIRE_TX) {
1680		mode = STM32H7_SPI_HALF_DUPLEX;
1681		stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_HDDIR);
1682	} else if (comm_type == SPI_SIMPLEX_RX) {
1683		mode = STM32H7_SPI_SIMPLEX_RX;
1684	} else if (comm_type == SPI_SIMPLEX_TX) {
1685		mode = STM32H7_SPI_SIMPLEX_TX;
1686	} else {
1687		mode = STM32H7_SPI_FULL_DUPLEX;
1688	}
1689
1690	cfg2_clrb |= STM32H7_SPI_CFG2_COMM;
1691	cfg2_setb |= FIELD_PREP(STM32H7_SPI_CFG2_COMM, mode);
1692
1693	writel_relaxed(
1694		(readl_relaxed(spi->base + STM32H7_SPI_CFG2) &
1695		 ~cfg2_clrb) | cfg2_setb,
1696		spi->base + STM32H7_SPI_CFG2);
1697
1698	return 0;
1699}
1700
1701/**
1702 * stm32h7_spi_data_idleness - configure minimum time delay inserted between two
1703 *			       consecutive data frames in host mode
1704 * @spi: pointer to the spi controller data structure
1705 * @len: transfer len
1706 */
1707static void stm32h7_spi_data_idleness(struct stm32_spi *spi, u32 len)
1708{
1709	u32 cfg2_clrb = 0, cfg2_setb = 0;
1710
1711	cfg2_clrb |= STM32H7_SPI_CFG2_MIDI;
1712	if ((len > 1) && (spi->cur_midi > 0)) {
1713		u32 sck_period_ns = DIV_ROUND_UP(NSEC_PER_SEC, spi->cur_speed);
1714		u32 midi = min_t(u32,
1715				 DIV_ROUND_UP(spi->cur_midi, sck_period_ns),
1716				 FIELD_GET(STM32H7_SPI_CFG2_MIDI,
1717				 STM32H7_SPI_CFG2_MIDI));
1718
1719
1720		dev_dbg(spi->dev, "period=%dns, midi=%d(=%dns)\n",
1721			sck_period_ns, midi, midi * sck_period_ns);
1722		cfg2_setb |= FIELD_PREP(STM32H7_SPI_CFG2_MIDI, midi);
1723	}
1724
1725	writel_relaxed((readl_relaxed(spi->base + STM32H7_SPI_CFG2) &
1726			~cfg2_clrb) | cfg2_setb,
1727		       spi->base + STM32H7_SPI_CFG2);
1728}
1729
1730/**
1731 * stm32h7_spi_number_of_data - configure number of data at current transfer
1732 * @spi: pointer to the spi controller data structure
1733 * @nb_words: transfer length (in words)
1734 */
1735static int stm32h7_spi_number_of_data(struct stm32_spi *spi, u32 nb_words)
1736{
1737	if (nb_words <= spi->t_size_max) {
1738		writel_relaxed(FIELD_PREP(STM32H7_SPI_CR2_TSIZE, nb_words),
1739			       spi->base + STM32H7_SPI_CR2);
1740	} else {
1741		return -EMSGSIZE;
1742	}
1743
1744	return 0;
1745}
1746
1747/**
1748 * stm32_spi_transfer_one_setup - common setup to transfer a single
1749 *				  spi_transfer either using DMA or
1750 *				  interrupts.
1751 * @spi: pointer to the spi controller data structure
1752 * @spi_dev: pointer to the spi device
1753 * @transfer: pointer to spi transfer
1754 */
1755static int stm32_spi_transfer_one_setup(struct stm32_spi *spi,
1756					struct spi_device *spi_dev,
1757					struct spi_transfer *transfer)
1758{
1759	unsigned long flags;
1760	unsigned int comm_type;
1761	int nb_words, ret = 0;
1762	int mbr;
1763
1764	spin_lock_irqsave(&spi->lock, flags);
1765
1766	spi->cur_xferlen = transfer->len;
1767
1768	spi->cur_bpw = transfer->bits_per_word;
1769	spi->cfg->set_bpw(spi);
1770
1771	/* Update spi->cur_speed with real clock speed */
1772	if (STM32_SPI_HOST_MODE(spi)) {
1773		mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz,
1774					    spi->cfg->baud_rate_div_min,
1775					    spi->cfg->baud_rate_div_max);
1776		if (mbr < 0) {
1777			ret = mbr;
1778			goto out;
1779		}
1780
1781		transfer->speed_hz = spi->cur_speed;
1782		stm32_spi_set_mbr(spi, mbr);
1783	}
1784
1785	comm_type = stm32_spi_communication_type(spi_dev, transfer);
1786	ret = spi->cfg->set_mode(spi, comm_type);
1787	if (ret < 0)
1788		goto out;
1789
1790	spi->cur_comm = comm_type;
1791
1792	if (STM32_SPI_HOST_MODE(spi) && spi->cfg->set_data_idleness)
1793		spi->cfg->set_data_idleness(spi, transfer->len);
1794
1795	if (spi->cur_bpw <= 8)
1796		nb_words = transfer->len;
1797	else if (spi->cur_bpw <= 16)
1798		nb_words = DIV_ROUND_UP(transfer->len * 8, 16);
1799	else
1800		nb_words = DIV_ROUND_UP(transfer->len * 8, 32);
1801
1802	if (spi->cfg->set_number_of_data) {
1803		ret = spi->cfg->set_number_of_data(spi, nb_words);
1804		if (ret < 0)
1805			goto out;
1806	}
1807
1808	dev_dbg(spi->dev, "transfer communication mode set to %d\n",
1809		spi->cur_comm);
1810	dev_dbg(spi->dev,
1811		"data frame of %d-bit, data packet of %d data frames\n",
1812		spi->cur_bpw, spi->cur_fthlv);
1813	if (STM32_SPI_HOST_MODE(spi))
1814		dev_dbg(spi->dev, "speed set to %dHz\n", spi->cur_speed);
1815	dev_dbg(spi->dev, "transfer of %d bytes (%d data frames)\n",
1816		spi->cur_xferlen, nb_words);
1817	dev_dbg(spi->dev, "dma %s\n",
1818		(spi->cur_usedma) ? "enabled" : "disabled");
1819
1820out:
1821	spin_unlock_irqrestore(&spi->lock, flags);
1822
1823	return ret;
1824}
1825
1826/**
1827 * stm32_spi_transfer_one - transfer a single spi_transfer
1828 * @ctrl: controller interface
1829 * @spi_dev: pointer to the spi device
1830 * @transfer: pointer to spi transfer
1831 *
1832 * It must return 0 if the transfer is finished or 1 if the transfer is still
1833 * in progress.
1834 */
1835static int stm32_spi_transfer_one(struct spi_controller *ctrl,
1836				  struct spi_device *spi_dev,
1837				  struct spi_transfer *transfer)
1838{
1839	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
1840	int ret;
1841
1842	spi->tx_buf = transfer->tx_buf;
1843	spi->rx_buf = transfer->rx_buf;
1844	spi->tx_len = spi->tx_buf ? transfer->len : 0;
1845	spi->rx_len = spi->rx_buf ? transfer->len : 0;
1846
1847	spi->cur_usedma = (ctrl->can_dma &&
1848			   ctrl->can_dma(ctrl, spi_dev, transfer));
1849
1850	ret = stm32_spi_transfer_one_setup(spi, spi_dev, transfer);
1851	if (ret) {
1852		dev_err(spi->dev, "SPI transfer setup failed\n");
1853		return ret;
1854	}
1855
1856	if (spi->cur_usedma)
1857		return stm32_spi_transfer_one_dma(spi, transfer);
1858	else
1859		return spi->cfg->transfer_one_irq(spi);
1860}
1861
1862/**
1863 * stm32_spi_unprepare_msg - relax the hardware
1864 * @ctrl: controller interface
1865 * @msg: pointer to the spi message
1866 */
1867static int stm32_spi_unprepare_msg(struct spi_controller *ctrl,
1868				   struct spi_message *msg)
1869{
1870	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
1871
1872	spi->cfg->disable(spi);
1873
1874	return 0;
1875}
1876
1877/**
1878 * stm32fx_spi_config - Configure SPI controller as SPI host
1879 * @spi: pointer to the spi controller data structure
1880 */
1881static int stm32fx_spi_config(struct stm32_spi *spi)
1882{
1883	unsigned long flags;
1884
1885	spin_lock_irqsave(&spi->lock, flags);
1886
1887	/* Ensure I2SMOD bit is kept cleared */
1888	stm32_spi_clr_bits(spi, STM32FX_SPI_I2SCFGR,
1889			   STM32FX_SPI_I2SCFGR_I2SMOD);
1890
1891	/*
1892	 * - SS input value high
1893	 * - transmitter half duplex direction
1894	 * - Set the host mode (default Motorola mode)
1895	 * - Consider 1 host/n targets configuration and
1896	 *   SS input value is determined by the SSI bit
1897	 */
1898	stm32_spi_set_bits(spi, STM32FX_SPI_CR1, STM32FX_SPI_CR1_SSI |
1899						 STM32FX_SPI_CR1_BIDIOE |
1900						 STM32FX_SPI_CR1_MSTR |
1901						 STM32FX_SPI_CR1_SSM);
1902
1903	spin_unlock_irqrestore(&spi->lock, flags);
1904
1905	return 0;
1906}
1907
1908/**
1909 * stm32h7_spi_config - Configure SPI controller
1910 * @spi: pointer to the spi controller data structure
1911 */
1912static int stm32h7_spi_config(struct stm32_spi *spi)
1913{
1914	unsigned long flags;
1915	u32 cr1 = 0, cfg2 = 0;
1916
1917	spin_lock_irqsave(&spi->lock, flags);
1918
1919	/* Ensure I2SMOD bit is kept cleared */
1920	stm32_spi_clr_bits(spi, STM32H7_SPI_I2SCFGR,
1921			   STM32H7_SPI_I2SCFGR_I2SMOD);
1922
1923	if (STM32_SPI_DEVICE_MODE(spi)) {
1924		/* Use native device select */
1925		cfg2 &= ~STM32H7_SPI_CFG2_SSM;
1926	} else {
1927		/*
1928		 * - Transmitter half duplex direction
1929		 * - Automatic communication suspend when RX-Fifo is full
1930		 * - SS input value high
1931		 */
1932		cr1 |= STM32H7_SPI_CR1_HDDIR | STM32H7_SPI_CR1_MASRX | STM32H7_SPI_CR1_SSI;
1933
1934		/*
1935		 * - Set the host mode (default Motorola mode)
1936		 * - Consider 1 host/n devices configuration and
1937		 *   SS input value is determined by the SSI bit
1938		 * - keep control of all associated GPIOs
1939		 */
1940		cfg2 |= STM32H7_SPI_CFG2_MASTER | STM32H7_SPI_CFG2_SSM | STM32H7_SPI_CFG2_AFCNTR;
1941	}
1942
1943	stm32_spi_set_bits(spi, STM32H7_SPI_CR1, cr1);
1944	stm32_spi_set_bits(spi, STM32H7_SPI_CFG2, cfg2);
1945
1946	spin_unlock_irqrestore(&spi->lock, flags);
1947
1948	return 0;
1949}
1950
1951static const struct stm32_spi_cfg stm32f4_spi_cfg = {
1952	.regs = &stm32fx_spi_regspec,
1953	.get_bpw_mask = stm32f4_spi_get_bpw_mask,
1954	.disable = stm32fx_spi_disable,
1955	.config = stm32fx_spi_config,
1956	.set_bpw = stm32f4_spi_set_bpw,
1957	.set_mode = stm32fx_spi_set_mode,
1958	.write_tx = stm32f4_spi_write_tx,
1959	.read_rx = stm32f4_spi_read_rx,
1960	.transfer_one_dma_start = stm32fx_spi_transfer_one_dma_start,
1961	.dma_tx_cb = stm32fx_spi_dma_tx_cb,
1962	.dma_rx_cb = stm32_spi_dma_rx_cb,
1963	.transfer_one_irq = stm32fx_spi_transfer_one_irq,
1964	.irq_handler_event = stm32fx_spi_irq_event,
1965	.irq_handler_thread = stm32fx_spi_irq_thread,
1966	.baud_rate_div_min = STM32FX_SPI_BR_DIV_MIN,
1967	.baud_rate_div_max = STM32FX_SPI_BR_DIV_MAX,
1968	.has_fifo = false,
1969	.has_device_mode = false,
1970	.flags = SPI_CONTROLLER_MUST_TX,
1971};
1972
1973static const struct stm32_spi_cfg stm32f7_spi_cfg = {
1974	.regs = &stm32fx_spi_regspec,
1975	.get_bpw_mask = stm32f7_spi_get_bpw_mask,
1976	.disable = stm32fx_spi_disable,
1977	.config = stm32fx_spi_config,
1978	.set_bpw = stm32f7_spi_set_bpw,
1979	.set_mode = stm32fx_spi_set_mode,
1980	.write_tx = stm32f7_spi_write_tx,
1981	.read_rx = stm32f7_spi_read_rx,
1982	.transfer_one_dma_start = stm32f7_spi_transfer_one_dma_start,
1983	.dma_tx_cb = stm32fx_spi_dma_tx_cb,
1984	.dma_rx_cb = stm32_spi_dma_rx_cb,
1985	.transfer_one_irq = stm32fx_spi_transfer_one_irq,
1986	.irq_handler_event = stm32fx_spi_irq_event,
1987	.irq_handler_thread = stm32fx_spi_irq_thread,
1988	.baud_rate_div_min = STM32FX_SPI_BR_DIV_MIN,
1989	.baud_rate_div_max = STM32FX_SPI_BR_DIV_MAX,
1990	.has_fifo = false,
1991	.flags = SPI_CONTROLLER_MUST_TX,
1992};
1993
1994static const struct stm32_spi_cfg stm32h7_spi_cfg = {
1995	.regs = &stm32h7_spi_regspec,
1996	.get_fifo_size = stm32h7_spi_get_fifo_size,
1997	.get_bpw_mask = stm32h7_spi_get_bpw_mask,
1998	.disable = stm32h7_spi_disable,
1999	.config = stm32h7_spi_config,
2000	.set_bpw = stm32h7_spi_set_bpw,
2001	.set_mode = stm32h7_spi_set_mode,
2002	.set_data_idleness = stm32h7_spi_data_idleness,
2003	.set_number_of_data = stm32h7_spi_number_of_data,
2004	.write_tx = stm32h7_spi_write_txfifo,
2005	.read_rx = stm32h7_spi_read_rxfifo,
2006	.transfer_one_dma_start = stm32h7_spi_transfer_one_dma_start,
2007	.dma_rx_cb = stm32_spi_dma_rx_cb,
2008	/*
2009	 * dma_tx_cb is not necessary since in case of TX, dma is followed by
2010	 * SPI access hence handling is performed within the SPI interrupt
2011	 */
2012	.transfer_one_irq = stm32h7_spi_transfer_one_irq,
2013	.irq_handler_thread = stm32h7_spi_irq_thread,
2014	.baud_rate_div_min = STM32H7_SPI_MBR_DIV_MIN,
2015	.baud_rate_div_max = STM32H7_SPI_MBR_DIV_MAX,
2016	.has_fifo = true,
2017	.has_device_mode = true,
2018};
2019
2020/*
2021 * STM32MP2 is compatible with the STM32H7 except:
2022 * - enforce the DMA maxburst value to 1
2023 * - spi8 have limited feature set (TSIZE_MAX = 1024, BPW of 8 OR 16)
2024 */
2025static const struct stm32_spi_cfg stm32mp25_spi_cfg = {
2026	.regs = &stm32mp25_spi_regspec,
2027	.get_fifo_size = stm32h7_spi_get_fifo_size,
2028	.get_bpw_mask = stm32mp25_spi_get_bpw_mask,
2029	.disable = stm32h7_spi_disable,
2030	.config = stm32h7_spi_config,
2031	.set_bpw = stm32h7_spi_set_bpw,
2032	.set_mode = stm32h7_spi_set_mode,
2033	.set_data_idleness = stm32h7_spi_data_idleness,
2034	.set_number_of_data = stm32h7_spi_number_of_data,
2035	.transfer_one_dma_start = stm32h7_spi_transfer_one_dma_start,
2036	.dma_rx_cb = stm32_spi_dma_rx_cb,
2037	/*
2038	 * dma_tx_cb is not necessary since in case of TX, dma is followed by
2039	 * SPI access hence handling is performed within the SPI interrupt
2040	 */
2041	.transfer_one_irq = stm32h7_spi_transfer_one_irq,
2042	.irq_handler_thread = stm32h7_spi_irq_thread,
2043	.baud_rate_div_min = STM32H7_SPI_MBR_DIV_MIN,
2044	.baud_rate_div_max = STM32H7_SPI_MBR_DIV_MAX,
2045	.has_fifo = true,
2046	.prevent_dma_burst = true,
2047};
2048
2049static const struct of_device_id stm32_spi_of_match[] = {
2050	{ .compatible = "st,stm32mp25-spi", .data = (void *)&stm32mp25_spi_cfg },
2051	{ .compatible = "st,stm32h7-spi", .data = (void *)&stm32h7_spi_cfg },
2052	{ .compatible = "st,stm32f4-spi", .data = (void *)&stm32f4_spi_cfg },
2053	{ .compatible = "st,stm32f7-spi", .data = (void *)&stm32f7_spi_cfg },
2054	{},
2055};
2056MODULE_DEVICE_TABLE(of, stm32_spi_of_match);
2057
2058static int stm32h7_spi_device_abort(struct spi_controller *ctrl)
2059{
2060	spi_finalize_current_transfer(ctrl);
2061	return 0;
2062}
2063
2064static int stm32_spi_probe(struct platform_device *pdev)
2065{
2066	struct spi_controller *ctrl;
2067	struct stm32_spi *spi;
2068	struct resource *res;
2069	struct reset_control *rst;
2070	struct device_node *np = pdev->dev.of_node;
2071	bool device_mode;
2072	int ret;
2073	const struct stm32_spi_cfg *cfg = of_device_get_match_data(&pdev->dev);
2074
2075	device_mode = of_property_read_bool(np, "spi-slave");
2076	if (!cfg->has_device_mode && device_mode) {
2077		dev_err(&pdev->dev, "spi-slave not supported\n");
2078		return -EPERM;
2079	}
2080
2081	if (device_mode)
2082		ctrl = devm_spi_alloc_target(&pdev->dev, sizeof(struct stm32_spi));
2083	else
2084		ctrl = devm_spi_alloc_host(&pdev->dev, sizeof(struct stm32_spi));
2085	if (!ctrl) {
2086		dev_err(&pdev->dev, "spi controller allocation failed\n");
2087		return -ENOMEM;
2088	}
2089	platform_set_drvdata(pdev, ctrl);
2090
2091	spi = spi_controller_get_devdata(ctrl);
2092	spi->dev = &pdev->dev;
2093	spi->ctrl = ctrl;
2094	spi->device_mode = device_mode;
2095	spin_lock_init(&spi->lock);
2096
2097	spi->cfg = cfg;
2098
2099	spi->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
2100	if (IS_ERR(spi->base))
2101		return PTR_ERR(spi->base);
2102
2103	spi->phys_addr = (dma_addr_t)res->start;
2104
2105	spi->irq = platform_get_irq(pdev, 0);
2106	if (spi->irq <= 0)
2107		return spi->irq;
2108
2109	ret = devm_request_threaded_irq(&pdev->dev, spi->irq,
2110					spi->cfg->irq_handler_event,
2111					spi->cfg->irq_handler_thread,
2112					IRQF_ONESHOT, pdev->name, ctrl);
2113	if (ret) {
2114		dev_err(&pdev->dev, "irq%d request failed: %d\n", spi->irq,
2115			ret);
2116		return ret;
2117	}
2118
2119	spi->clk = devm_clk_get(&pdev->dev, NULL);
2120	if (IS_ERR(spi->clk)) {
2121		ret = PTR_ERR(spi->clk);
2122		dev_err(&pdev->dev, "clk get failed: %d\n", ret);
2123		return ret;
2124	}
2125
2126	ret = clk_prepare_enable(spi->clk);
2127	if (ret) {
2128		dev_err(&pdev->dev, "clk enable failed: %d\n", ret);
2129		return ret;
2130	}
2131	spi->clk_rate = clk_get_rate(spi->clk);
2132	if (!spi->clk_rate) {
2133		dev_err(&pdev->dev, "clk rate = 0\n");
2134		ret = -EINVAL;
2135		goto err_clk_disable;
2136	}
2137
2138	rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
2139	if (rst) {
2140		if (IS_ERR(rst)) {
2141			ret = dev_err_probe(&pdev->dev, PTR_ERR(rst),
2142					    "failed to get reset\n");
2143			goto err_clk_disable;
2144		}
2145
2146		reset_control_assert(rst);
2147		udelay(2);
2148		reset_control_deassert(rst);
2149	}
2150
2151	if (spi->cfg->has_fifo)
2152		spi->fifo_size = spi->cfg->get_fifo_size(spi);
2153
2154	spi->feature_set = STM32_SPI_FEATURE_FULL;
2155	if (spi->cfg->regs->fullcfg.reg) {
2156		spi->feature_set =
2157			FIELD_GET(STM32MP25_SPI_HWCFGR1_FULLCFG,
2158				  readl_relaxed(spi->base + spi->cfg->regs->fullcfg.reg));
2159
2160		dev_dbg(spi->dev, "%s feature set\n",
2161			spi->feature_set == STM32_SPI_FEATURE_FULL ? "full" : "limited");
2162	}
2163
2164	/* Only for STM32H7 and after */
2165	spi->t_size_max = spi->feature_set == STM32_SPI_FEATURE_FULL ?
2166				STM32H7_SPI_TSIZE_MAX :
2167				STM32MP25_SPI_TSIZE_MAX_LIMITED;
2168	dev_dbg(spi->dev, "one message max size %d\n", spi->t_size_max);
2169
2170	ret = spi->cfg->config(spi);
2171	if (ret) {
2172		dev_err(&pdev->dev, "controller configuration failed: %d\n",
2173			ret);
2174		goto err_clk_disable;
2175	}
2176
2177	ctrl->dev.of_node = pdev->dev.of_node;
2178	ctrl->auto_runtime_pm = true;
2179	ctrl->bus_num = pdev->id;
2180	ctrl->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | SPI_LSB_FIRST |
2181			  SPI_3WIRE;
2182	ctrl->bits_per_word_mask = spi->cfg->get_bpw_mask(spi);
2183	ctrl->max_speed_hz = spi->clk_rate / spi->cfg->baud_rate_div_min;
2184	ctrl->min_speed_hz = spi->clk_rate / spi->cfg->baud_rate_div_max;
2185	ctrl->use_gpio_descriptors = true;
2186	ctrl->optimize_message = stm32_spi_optimize_message;
2187	ctrl->prepare_message = stm32_spi_prepare_msg;
2188	ctrl->transfer_one = stm32_spi_transfer_one;
2189	ctrl->unprepare_message = stm32_spi_unprepare_msg;
2190	ctrl->flags = spi->cfg->flags;
2191	if (STM32_SPI_DEVICE_MODE(spi))
2192		ctrl->target_abort = stm32h7_spi_device_abort;
2193
2194	spi->dma_tx = dma_request_chan(spi->dev, "tx");
2195	if (IS_ERR(spi->dma_tx)) {
2196		ret = PTR_ERR(spi->dma_tx);
2197		spi->dma_tx = NULL;
2198		if (ret == -EPROBE_DEFER)
2199			goto err_clk_disable;
2200
2201		dev_warn(&pdev->dev, "failed to request tx dma channel\n");
2202	} else {
2203		ctrl->dma_tx = spi->dma_tx;
2204	}
2205
2206	spi->dma_rx = dma_request_chan(spi->dev, "rx");
2207	if (IS_ERR(spi->dma_rx)) {
2208		ret = PTR_ERR(spi->dma_rx);
2209		spi->dma_rx = NULL;
2210		if (ret == -EPROBE_DEFER)
2211			goto err_dma_release;
2212
2213		dev_warn(&pdev->dev, "failed to request rx dma channel\n");
2214	} else {
2215		ctrl->dma_rx = spi->dma_rx;
2216	}
2217
2218	if (spi->dma_tx || spi->dma_rx)
2219		ctrl->can_dma = stm32_spi_can_dma;
2220
2221	pm_runtime_set_autosuspend_delay(&pdev->dev,
2222					 STM32_SPI_AUTOSUSPEND_DELAY);
2223	pm_runtime_use_autosuspend(&pdev->dev);
2224	pm_runtime_set_active(&pdev->dev);
2225	pm_runtime_get_noresume(&pdev->dev);
2226	pm_runtime_enable(&pdev->dev);
2227
2228	ret = spi_register_controller(ctrl);
2229	if (ret) {
2230		dev_err(&pdev->dev, "spi controller registration failed: %d\n",
2231			ret);
2232		goto err_pm_disable;
2233	}
2234
2235	pm_runtime_mark_last_busy(&pdev->dev);
2236	pm_runtime_put_autosuspend(&pdev->dev);
2237
2238	dev_info(&pdev->dev, "driver initialized (%s mode)\n",
2239		 STM32_SPI_HOST_MODE(spi) ? "host" : "device");
2240
2241	return 0;
2242
2243err_pm_disable:
2244	pm_runtime_disable(&pdev->dev);
2245	pm_runtime_put_noidle(&pdev->dev);
2246	pm_runtime_set_suspended(&pdev->dev);
2247	pm_runtime_dont_use_autosuspend(&pdev->dev);
2248err_dma_release:
2249	if (spi->dma_tx)
2250		dma_release_channel(spi->dma_tx);
2251	if (spi->dma_rx)
2252		dma_release_channel(spi->dma_rx);
2253err_clk_disable:
2254	clk_disable_unprepare(spi->clk);
2255
2256	return ret;
2257}
2258
2259static void stm32_spi_remove(struct platform_device *pdev)
2260{
2261	struct spi_controller *ctrl = platform_get_drvdata(pdev);
2262	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
2263
2264	pm_runtime_get_sync(&pdev->dev);
2265
2266	spi_unregister_controller(ctrl);
2267	spi->cfg->disable(spi);
2268
2269	pm_runtime_disable(&pdev->dev);
2270	pm_runtime_put_noidle(&pdev->dev);
2271	pm_runtime_set_suspended(&pdev->dev);
2272	pm_runtime_dont_use_autosuspend(&pdev->dev);
2273
2274	if (ctrl->dma_tx)
2275		dma_release_channel(ctrl->dma_tx);
2276	if (ctrl->dma_rx)
2277		dma_release_channel(ctrl->dma_rx);
2278
2279	clk_disable_unprepare(spi->clk);
2280
2281
2282	pinctrl_pm_select_sleep_state(&pdev->dev);
2283}
2284
2285static int __maybe_unused stm32_spi_runtime_suspend(struct device *dev)
2286{
2287	struct spi_controller *ctrl = dev_get_drvdata(dev);
2288	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
2289
2290	clk_disable_unprepare(spi->clk);
2291
2292	return pinctrl_pm_select_sleep_state(dev);
2293}
2294
2295static int __maybe_unused stm32_spi_runtime_resume(struct device *dev)
2296{
2297	struct spi_controller *ctrl = dev_get_drvdata(dev);
2298	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
2299	int ret;
2300
2301	ret = pinctrl_pm_select_default_state(dev);
2302	if (ret)
2303		return ret;
2304
2305	return clk_prepare_enable(spi->clk);
2306}
2307
2308static int __maybe_unused stm32_spi_suspend(struct device *dev)
2309{
2310	struct spi_controller *ctrl = dev_get_drvdata(dev);
2311	int ret;
2312
2313	ret = spi_controller_suspend(ctrl);
2314	if (ret)
2315		return ret;
2316
2317	return pm_runtime_force_suspend(dev);
2318}
2319
2320static int __maybe_unused stm32_spi_resume(struct device *dev)
2321{
2322	struct spi_controller *ctrl = dev_get_drvdata(dev);
2323	struct stm32_spi *spi = spi_controller_get_devdata(ctrl);
2324	int ret;
2325
2326	ret = pm_runtime_force_resume(dev);
2327	if (ret)
2328		return ret;
2329
2330	ret = spi_controller_resume(ctrl);
2331	if (ret) {
2332		clk_disable_unprepare(spi->clk);
2333		return ret;
2334	}
2335
2336	ret = pm_runtime_resume_and_get(dev);
2337	if (ret < 0) {
2338		dev_err(dev, "Unable to power device:%d\n", ret);
2339		return ret;
2340	}
2341
2342	spi->cfg->config(spi);
2343
2344	pm_runtime_mark_last_busy(dev);
2345	pm_runtime_put_autosuspend(dev);
2346
2347	return 0;
2348}
2349
2350static const struct dev_pm_ops stm32_spi_pm_ops = {
2351	SET_SYSTEM_SLEEP_PM_OPS(stm32_spi_suspend, stm32_spi_resume)
2352	SET_RUNTIME_PM_OPS(stm32_spi_runtime_suspend,
2353			   stm32_spi_runtime_resume, NULL)
2354};
2355
2356static struct platform_driver stm32_spi_driver = {
2357	.probe = stm32_spi_probe,
2358	.remove_new = stm32_spi_remove,
2359	.driver = {
2360		.name = DRIVER_NAME,
2361		.pm = &stm32_spi_pm_ops,
2362		.of_match_table = stm32_spi_of_match,
2363	},
2364};
2365
2366module_platform_driver(stm32_spi_driver);
2367
2368MODULE_ALIAS("platform:" DRIVER_NAME);
2369MODULE_DESCRIPTION("STMicroelectronics STM32 SPI Controller driver");
2370MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay@st.com>");
2371MODULE_LICENSE("GPL v2");
2372