1// SPDX-License-Identifier: GPL-2.0+
2//
3// Copyright (c) 2009 Samsung Electronics Co., Ltd.
4//      Jaswinder Singh <jassi.brar@samsung.com>
5
6#include <linux/bitops.h>
7#include <linux/bits.h>
8#include <linux/clk.h>
9#include <linux/delay.h>
10#include <linux/dma-mapping.h>
11#include <linux/dmaengine.h>
12#include <linux/init.h>
13#include <linux/interrupt.h>
14#include <linux/io.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/platform_data/spi-s3c64xx.h>
18#include <linux/platform_device.h>
19#include <linux/pm_runtime.h>
20#include <linux/spi/spi.h>
21#include <linux/types.h>
22
23#define MAX_SPI_PORTS		12
24#define S3C64XX_SPI_QUIRK_CS_AUTO	(1 << 1)
25#define AUTOSUSPEND_TIMEOUT	2000
26
27/* Registers and bit-fields */
28
29#define S3C64XX_SPI_CH_CFG		0x00
30#define S3C64XX_SPI_CLK_CFG		0x04
31#define S3C64XX_SPI_MODE_CFG		0x08
32#define S3C64XX_SPI_CS_REG		0x0C
33#define S3C64XX_SPI_INT_EN		0x10
34#define S3C64XX_SPI_STATUS		0x14
35#define S3C64XX_SPI_TX_DATA		0x18
36#define S3C64XX_SPI_RX_DATA		0x1C
37#define S3C64XX_SPI_PACKET_CNT		0x20
38#define S3C64XX_SPI_PENDING_CLR		0x24
39#define S3C64XX_SPI_SWAP_CFG		0x28
40#define S3C64XX_SPI_FB_CLK		0x2C
41
42#define S3C64XX_SPI_CH_HS_EN		(1<<6)	/* High Speed Enable */
43#define S3C64XX_SPI_CH_SW_RST		(1<<5)
44#define S3C64XX_SPI_CH_SLAVE		(1<<4)
45#define S3C64XX_SPI_CPOL_L		(1<<3)
46#define S3C64XX_SPI_CPHA_B		(1<<2)
47#define S3C64XX_SPI_CH_RXCH_ON		(1<<1)
48#define S3C64XX_SPI_CH_TXCH_ON		(1<<0)
49
50#define S3C64XX_SPI_CLKSEL_SRCMSK	(3<<9)
51#define S3C64XX_SPI_CLKSEL_SRCSHFT	9
52#define S3C64XX_SPI_ENCLK_ENABLE	(1<<8)
53#define S3C64XX_SPI_PSR_MASK		0xff
54
55#define S3C64XX_SPI_MODE_CH_TSZ_BYTE		(0<<29)
56#define S3C64XX_SPI_MODE_CH_TSZ_HALFWORD	(1<<29)
57#define S3C64XX_SPI_MODE_CH_TSZ_WORD		(2<<29)
58#define S3C64XX_SPI_MODE_CH_TSZ_MASK		(3<<29)
59#define S3C64XX_SPI_MODE_BUS_TSZ_BYTE		(0<<17)
60#define S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD	(1<<17)
61#define S3C64XX_SPI_MODE_BUS_TSZ_WORD		(2<<17)
62#define S3C64XX_SPI_MODE_BUS_TSZ_MASK		(3<<17)
63#define S3C64XX_SPI_MODE_RX_RDY_LVL		GENMASK(16, 11)
64#define S3C64XX_SPI_MODE_RX_RDY_LVL_SHIFT	11
65#define S3C64XX_SPI_MODE_SELF_LOOPBACK		(1<<3)
66#define S3C64XX_SPI_MODE_RXDMA_ON		(1<<2)
67#define S3C64XX_SPI_MODE_TXDMA_ON		(1<<1)
68#define S3C64XX_SPI_MODE_4BURST			(1<<0)
69
70#define S3C64XX_SPI_CS_NSC_CNT_2		(2<<4)
71#define S3C64XX_SPI_CS_AUTO			(1<<1)
72#define S3C64XX_SPI_CS_SIG_INACT		(1<<0)
73
74#define S3C64XX_SPI_INT_TRAILING_EN		(1<<6)
75#define S3C64XX_SPI_INT_RX_OVERRUN_EN		(1<<5)
76#define S3C64XX_SPI_INT_RX_UNDERRUN_EN		(1<<4)
77#define S3C64XX_SPI_INT_TX_OVERRUN_EN		(1<<3)
78#define S3C64XX_SPI_INT_TX_UNDERRUN_EN		(1<<2)
79#define S3C64XX_SPI_INT_RX_FIFORDY_EN		(1<<1)
80#define S3C64XX_SPI_INT_TX_FIFORDY_EN		(1<<0)
81
82#define S3C64XX_SPI_ST_RX_FIFO_RDY_V2		GENMASK(23, 15)
83#define S3C64XX_SPI_ST_TX_FIFO_RDY_V2		GENMASK(14, 6)
84#define S3C64XX_SPI_ST_TX_FIFO_LVL_SHIFT	6
85#define S3C64XX_SPI_ST_RX_OVERRUN_ERR		(1<<5)
86#define S3C64XX_SPI_ST_RX_UNDERRUN_ERR		(1<<4)
87#define S3C64XX_SPI_ST_TX_OVERRUN_ERR		(1<<3)
88#define S3C64XX_SPI_ST_TX_UNDERRUN_ERR		(1<<2)
89#define S3C64XX_SPI_ST_RX_FIFORDY		(1<<1)
90#define S3C64XX_SPI_ST_TX_FIFORDY		(1<<0)
91
92#define S3C64XX_SPI_PACKET_CNT_EN		(1<<16)
93#define S3C64XX_SPI_PACKET_CNT_MASK		GENMASK(15, 0)
94
95#define S3C64XX_SPI_PND_TX_UNDERRUN_CLR		(1<<4)
96#define S3C64XX_SPI_PND_TX_OVERRUN_CLR		(1<<3)
97#define S3C64XX_SPI_PND_RX_UNDERRUN_CLR		(1<<2)
98#define S3C64XX_SPI_PND_RX_OVERRUN_CLR		(1<<1)
99#define S3C64XX_SPI_PND_TRAILING_CLR		(1<<0)
100
101#define S3C64XX_SPI_SWAP_RX_HALF_WORD		(1<<7)
102#define S3C64XX_SPI_SWAP_RX_BYTE		(1<<6)
103#define S3C64XX_SPI_SWAP_RX_BIT			(1<<5)
104#define S3C64XX_SPI_SWAP_RX_EN			(1<<4)
105#define S3C64XX_SPI_SWAP_TX_HALF_WORD		(1<<3)
106#define S3C64XX_SPI_SWAP_TX_BYTE		(1<<2)
107#define S3C64XX_SPI_SWAP_TX_BIT			(1<<1)
108#define S3C64XX_SPI_SWAP_TX_EN			(1<<0)
109
110#define S3C64XX_SPI_FBCLK_MSK			(3<<0)
111
112#define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
113#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
114				(1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
115#define TX_FIFO_LVL(v, sdd)	(((v) & (sdd)->tx_fifomask) >>		\
116				 __ffs((sdd)->tx_fifomask))
117#define RX_FIFO_LVL(v, sdd)	(((v) & (sdd)->rx_fifomask) >>		\
118				 __ffs((sdd)->rx_fifomask))
119#define FIFO_DEPTH(i) ((FIFO_LVL_MASK(i) >> 1) + 1)
120
121#define S3C64XX_SPI_MAX_TRAILCNT	0x3ff
122#define S3C64XX_SPI_TRAILCNT_OFF	19
123
124#define S3C64XX_SPI_POLLING_SIZE	32
125
126#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
127#define is_polling(x)	(x->cntrlr_info->polling)
128
129#define RXBUSY    (1<<2)
130#define TXBUSY    (1<<3)
131
132struct s3c64xx_spi_dma_data {
133	struct dma_chan *ch;
134	dma_cookie_t cookie;
135	enum dma_transfer_direction direction;
136};
137
138/**
139 * struct s3c64xx_spi_port_config - SPI Controller hardware info
140 * @fifo_lvl_mask: [DEPRECATED] use @{rx, tx}_fifomask instead.
141 * @rx_lvl_offset: [DEPRECATED] use @{rx,tx}_fifomask instead.
142 * @fifo_depth: depth of the FIFO.
143 * @rx_fifomask: SPI_STATUS.RX_FIFO_LVL mask. Shifted mask defining the field's
144 *               length and position.
145 * @tx_fifomask: SPI_STATUS.TX_FIFO_LVL mask. Shifted mask defining the field's
146 *               length and position.
147 * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
148 * @clk_div: Internal clock divider
149 * @quirks: Bitmask of known quirks
150 * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
151 * @clk_from_cmu: True, if the controller does not include a clock mux and
152 *	prescaler unit.
153 * @clk_ioclk: True if clock is present on this device
154 * @has_loopback: True if loopback mode can be supported
155 * @use_32bit_io: True if the SoC allows only 32-bit register accesses.
156 *
157 * The Samsung s3c64xx SPI controller are used on various Samsung SoC's but
158 * differ in some aspects such as the size of the fifo and spi bus clock
159 * setup. Such differences are specified to the driver using this structure
160 * which is provided as driver data to the driver.
161 */
162struct s3c64xx_spi_port_config {
163	int	fifo_lvl_mask[MAX_SPI_PORTS];
164	int	rx_lvl_offset;
165	unsigned int fifo_depth;
166	u32	rx_fifomask;
167	u32	tx_fifomask;
168	int	tx_st_done;
169	int	quirks;
170	int	clk_div;
171	bool	high_speed;
172	bool	clk_from_cmu;
173	bool	clk_ioclk;
174	bool	has_loopback;
175	bool	use_32bit_io;
176};
177
178/**
179 * struct s3c64xx_spi_driver_data - Runtime info holder for SPI driver.
180 * @clk: Pointer to the spi clock.
181 * @src_clk: Pointer to the clock used to generate SPI signals.
182 * @ioclk: Pointer to the i/o clock between host and target
183 * @pdev: Pointer to device's platform device data
184 * @host: Pointer to the SPI Protocol host.
185 * @cntrlr_info: Platform specific data for the controller this driver manages.
186 * @lock: Controller specific lock.
187 * @state: Set of FLAGS to indicate status.
188 * @sfr_start: BUS address of SPI controller regs.
189 * @regs: Pointer to ioremap'ed controller registers.
190 * @xfer_completion: To indicate completion of xfer task.
191 * @cur_mode: Stores the active configuration of the controller.
192 * @cur_bpw: Stores the active bits per word settings.
193 * @cur_speed: Current clock speed
194 * @rx_dma: Local receive DMA data (e.g. chan and direction)
195 * @tx_dma: Local transmit DMA data (e.g. chan and direction)
196 * @port_conf: Local SPI port configuration data
197 * @port_id: [DEPRECATED] use @{rx,tx}_fifomask instead.
198 * @fifo_depth: depth of the FIFO.
199 * @rx_fifomask: SPI_STATUS.RX_FIFO_LVL mask. Shifted mask defining the field's
200 *               length and position.
201 * @tx_fifomask: SPI_STATUS.TX_FIFO_LVL mask. Shifted mask defining the field's
202 *               length and position.
203 */
204struct s3c64xx_spi_driver_data {
205	void __iomem                    *regs;
206	struct clk                      *clk;
207	struct clk                      *src_clk;
208	struct clk                      *ioclk;
209	struct platform_device          *pdev;
210	struct spi_controller           *host;
211	struct s3c64xx_spi_info         *cntrlr_info;
212	spinlock_t                      lock;
213	unsigned long                   sfr_start;
214	struct completion               xfer_completion;
215	unsigned                        state;
216	unsigned                        cur_mode, cur_bpw;
217	unsigned                        cur_speed;
218	struct s3c64xx_spi_dma_data	rx_dma;
219	struct s3c64xx_spi_dma_data	tx_dma;
220	const struct s3c64xx_spi_port_config	*port_conf;
221	unsigned int			port_id;
222	unsigned int			fifo_depth;
223	u32				rx_fifomask;
224	u32				tx_fifomask;
225};
226
227static void s3c64xx_flush_fifo(struct s3c64xx_spi_driver_data *sdd)
228{
229	void __iomem *regs = sdd->regs;
230	unsigned long loops;
231	u32 val;
232
233	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
234
235	val = readl(regs + S3C64XX_SPI_CH_CFG);
236	val &= ~(S3C64XX_SPI_CH_RXCH_ON | S3C64XX_SPI_CH_TXCH_ON);
237	writel(val, regs + S3C64XX_SPI_CH_CFG);
238
239	val = readl(regs + S3C64XX_SPI_CH_CFG);
240	val |= S3C64XX_SPI_CH_SW_RST;
241	val &= ~S3C64XX_SPI_CH_HS_EN;
242	writel(val, regs + S3C64XX_SPI_CH_CFG);
243
244	/* Flush TxFIFO*/
245	loops = msecs_to_loops(1);
246	do {
247		val = readl(regs + S3C64XX_SPI_STATUS);
248	} while (TX_FIFO_LVL(val, sdd) && loops--);
249
250	if (loops == 0)
251		dev_warn(&sdd->pdev->dev, "Timed out flushing TX FIFO\n");
252
253	/* Flush RxFIFO*/
254	loops = msecs_to_loops(1);
255	do {
256		val = readl(regs + S3C64XX_SPI_STATUS);
257		if (RX_FIFO_LVL(val, sdd))
258			readl(regs + S3C64XX_SPI_RX_DATA);
259		else
260			break;
261	} while (loops--);
262
263	if (loops == 0)
264		dev_warn(&sdd->pdev->dev, "Timed out flushing RX FIFO\n");
265
266	val = readl(regs + S3C64XX_SPI_CH_CFG);
267	val &= ~S3C64XX_SPI_CH_SW_RST;
268	writel(val, regs + S3C64XX_SPI_CH_CFG);
269
270	val = readl(regs + S3C64XX_SPI_MODE_CFG);
271	val &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
272	writel(val, regs + S3C64XX_SPI_MODE_CFG);
273}
274
275static void s3c64xx_spi_dmacb(void *data)
276{
277	struct s3c64xx_spi_driver_data *sdd;
278	struct s3c64xx_spi_dma_data *dma = data;
279	unsigned long flags;
280
281	if (dma->direction == DMA_DEV_TO_MEM)
282		sdd = container_of(data,
283			struct s3c64xx_spi_driver_data, rx_dma);
284	else
285		sdd = container_of(data,
286			struct s3c64xx_spi_driver_data, tx_dma);
287
288	spin_lock_irqsave(&sdd->lock, flags);
289
290	if (dma->direction == DMA_DEV_TO_MEM) {
291		sdd->state &= ~RXBUSY;
292		if (!(sdd->state & TXBUSY))
293			complete(&sdd->xfer_completion);
294	} else {
295		sdd->state &= ~TXBUSY;
296		if (!(sdd->state & RXBUSY))
297			complete(&sdd->xfer_completion);
298	}
299
300	spin_unlock_irqrestore(&sdd->lock, flags);
301}
302
303static int s3c64xx_prepare_dma(struct s3c64xx_spi_dma_data *dma,
304			       struct sg_table *sgt)
305{
306	struct s3c64xx_spi_driver_data *sdd;
307	struct dma_slave_config config;
308	struct dma_async_tx_descriptor *desc;
309	int ret;
310
311	memset(&config, 0, sizeof(config));
312
313	if (dma->direction == DMA_DEV_TO_MEM) {
314		sdd = container_of((void *)dma,
315			struct s3c64xx_spi_driver_data, rx_dma);
316		config.src_addr = sdd->sfr_start + S3C64XX_SPI_RX_DATA;
317		config.src_addr_width = sdd->cur_bpw / 8;
318		config.src_maxburst = 1;
319	} else {
320		sdd = container_of((void *)dma,
321			struct s3c64xx_spi_driver_data, tx_dma);
322		config.dst_addr = sdd->sfr_start + S3C64XX_SPI_TX_DATA;
323		config.dst_addr_width = sdd->cur_bpw / 8;
324		config.dst_maxburst = 1;
325	}
326	config.direction = dma->direction;
327	ret = dmaengine_slave_config(dma->ch, &config);
328	if (ret)
329		return ret;
330
331	desc = dmaengine_prep_slave_sg(dma->ch, sgt->sgl, sgt->nents,
332				       dma->direction, DMA_PREP_INTERRUPT);
333	if (!desc) {
334		dev_err(&sdd->pdev->dev, "unable to prepare %s scatterlist",
335			dma->direction == DMA_DEV_TO_MEM ? "rx" : "tx");
336		return -ENOMEM;
337	}
338
339	desc->callback = s3c64xx_spi_dmacb;
340	desc->callback_param = dma;
341
342	dma->cookie = dmaengine_submit(desc);
343	ret = dma_submit_error(dma->cookie);
344	if (ret) {
345		dev_err(&sdd->pdev->dev, "DMA submission failed");
346		return ret;
347	}
348
349	dma_async_issue_pending(dma->ch);
350	return 0;
351}
352
353static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
354{
355	struct s3c64xx_spi_driver_data *sdd =
356					spi_controller_get_devdata(spi->controller);
357
358	if (sdd->cntrlr_info->no_cs)
359		return;
360
361	if (enable) {
362		if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
363			writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
364		} else {
365			u32 ssel = readl(sdd->regs + S3C64XX_SPI_CS_REG);
366
367			ssel |= (S3C64XX_SPI_CS_AUTO |
368						S3C64XX_SPI_CS_NSC_CNT_2);
369			writel(ssel, sdd->regs + S3C64XX_SPI_CS_REG);
370		}
371	} else {
372		if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
373			writel(S3C64XX_SPI_CS_SIG_INACT,
374			       sdd->regs + S3C64XX_SPI_CS_REG);
375	}
376}
377
378static int s3c64xx_spi_prepare_transfer(struct spi_controller *spi)
379{
380	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(spi);
381
382	if (is_polling(sdd))
383		return 0;
384
385	/* Requests DMA channels */
386	sdd->rx_dma.ch = dma_request_chan(&sdd->pdev->dev, "rx");
387	if (IS_ERR(sdd->rx_dma.ch)) {
388		dev_err(&sdd->pdev->dev, "Failed to get RX DMA channel\n");
389		sdd->rx_dma.ch = NULL;
390		return 0;
391	}
392
393	sdd->tx_dma.ch = dma_request_chan(&sdd->pdev->dev, "tx");
394	if (IS_ERR(sdd->tx_dma.ch)) {
395		dev_err(&sdd->pdev->dev, "Failed to get TX DMA channel\n");
396		dma_release_channel(sdd->rx_dma.ch);
397		sdd->tx_dma.ch = NULL;
398		sdd->rx_dma.ch = NULL;
399		return 0;
400	}
401
402	spi->dma_rx = sdd->rx_dma.ch;
403	spi->dma_tx = sdd->tx_dma.ch;
404
405	return 0;
406}
407
408static int s3c64xx_spi_unprepare_transfer(struct spi_controller *spi)
409{
410	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(spi);
411
412	if (is_polling(sdd))
413		return 0;
414
415	/* Releases DMA channels if they are allocated */
416	if (sdd->rx_dma.ch && sdd->tx_dma.ch) {
417		dma_release_channel(sdd->rx_dma.ch);
418		dma_release_channel(sdd->tx_dma.ch);
419		sdd->rx_dma.ch = NULL;
420		sdd->tx_dma.ch = NULL;
421	}
422
423	return 0;
424}
425
426static bool s3c64xx_spi_can_dma(struct spi_controller *host,
427				struct spi_device *spi,
428				struct spi_transfer *xfer)
429{
430	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
431
432	if (sdd->rx_dma.ch && sdd->tx_dma.ch)
433		return xfer->len >= sdd->fifo_depth;
434
435	return false;
436}
437
438static void s3c64xx_iowrite8_32_rep(volatile void __iomem *addr,
439				    const void *buffer, unsigned int count)
440{
441	if (count) {
442		const u8 *buf = buffer;
443
444		do {
445			__raw_writel(*buf++, addr);
446		} while (--count);
447	}
448}
449
450static void s3c64xx_iowrite16_32_rep(volatile void __iomem *addr,
451				     const void *buffer, unsigned int count)
452{
453	if (count) {
454		const u16 *buf = buffer;
455
456		do {
457			__raw_writel(*buf++, addr);
458		} while (--count);
459	}
460}
461
462static void s3c64xx_iowrite_rep(const struct s3c64xx_spi_driver_data *sdd,
463				struct spi_transfer *xfer)
464{
465	void __iomem *addr = sdd->regs + S3C64XX_SPI_TX_DATA;
466	const void *buf = xfer->tx_buf;
467	unsigned int len = xfer->len;
468
469	switch (sdd->cur_bpw) {
470	case 32:
471		iowrite32_rep(addr, buf, len / 4);
472		break;
473	case 16:
474		if (sdd->port_conf->use_32bit_io)
475			s3c64xx_iowrite16_32_rep(addr, buf, len / 2);
476		else
477			iowrite16_rep(addr, buf, len / 2);
478		break;
479	default:
480		if (sdd->port_conf->use_32bit_io)
481			s3c64xx_iowrite8_32_rep(addr, buf, len);
482		else
483			iowrite8_rep(addr, buf, len);
484		break;
485	}
486}
487
488static int s3c64xx_enable_datapath(struct s3c64xx_spi_driver_data *sdd,
489				    struct spi_transfer *xfer, int dma_mode)
490{
491	void __iomem *regs = sdd->regs;
492	u32 modecfg, chcfg;
493	int ret = 0;
494
495	modecfg = readl(regs + S3C64XX_SPI_MODE_CFG);
496	modecfg &= ~(S3C64XX_SPI_MODE_TXDMA_ON | S3C64XX_SPI_MODE_RXDMA_ON);
497
498	chcfg = readl(regs + S3C64XX_SPI_CH_CFG);
499	chcfg &= ~S3C64XX_SPI_CH_TXCH_ON;
500
501	if (dma_mode) {
502		chcfg &= ~S3C64XX_SPI_CH_RXCH_ON;
503	} else {
504		/* Always shift in data in FIFO, even if xfer is Tx only,
505		 * this helps setting PCKT_CNT value for generating clocks
506		 * as exactly needed.
507		 */
508		chcfg |= S3C64XX_SPI_CH_RXCH_ON;
509		writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
510					| S3C64XX_SPI_PACKET_CNT_EN,
511					regs + S3C64XX_SPI_PACKET_CNT);
512	}
513
514	if (xfer->tx_buf != NULL) {
515		sdd->state |= TXBUSY;
516		chcfg |= S3C64XX_SPI_CH_TXCH_ON;
517		if (dma_mode) {
518			modecfg |= S3C64XX_SPI_MODE_TXDMA_ON;
519			ret = s3c64xx_prepare_dma(&sdd->tx_dma, &xfer->tx_sg);
520		} else {
521			s3c64xx_iowrite_rep(sdd, xfer);
522		}
523	}
524
525	if (xfer->rx_buf != NULL) {
526		sdd->state |= RXBUSY;
527
528		if (sdd->port_conf->high_speed && sdd->cur_speed >= 30000000UL
529					&& !(sdd->cur_mode & SPI_CPHA))
530			chcfg |= S3C64XX_SPI_CH_HS_EN;
531
532		if (dma_mode) {
533			modecfg |= S3C64XX_SPI_MODE_RXDMA_ON;
534			chcfg |= S3C64XX_SPI_CH_RXCH_ON;
535			writel(((xfer->len * 8 / sdd->cur_bpw) & 0xffff)
536					| S3C64XX_SPI_PACKET_CNT_EN,
537					regs + S3C64XX_SPI_PACKET_CNT);
538			ret = s3c64xx_prepare_dma(&sdd->rx_dma, &xfer->rx_sg);
539		}
540	}
541
542	if (ret)
543		return ret;
544
545	writel(modecfg, regs + S3C64XX_SPI_MODE_CFG);
546	writel(chcfg, regs + S3C64XX_SPI_CH_CFG);
547
548	return 0;
549}
550
551static u32 s3c64xx_spi_wait_for_timeout(struct s3c64xx_spi_driver_data *sdd,
552					int timeout_ms)
553{
554	void __iomem *regs = sdd->regs;
555	unsigned long val = 1;
556	u32 status;
557	u32 max_fifo = sdd->fifo_depth;
558
559	if (timeout_ms)
560		val = msecs_to_loops(timeout_ms);
561
562	do {
563		status = readl(regs + S3C64XX_SPI_STATUS);
564	} while (RX_FIFO_LVL(status, sdd) < max_fifo && --val);
565
566	/* return the actual received data length */
567	return RX_FIFO_LVL(status, sdd);
568}
569
570static int s3c64xx_wait_for_dma(struct s3c64xx_spi_driver_data *sdd,
571				struct spi_transfer *xfer)
572{
573	void __iomem *regs = sdd->regs;
574	unsigned long val;
575	u32 status;
576	int ms;
577
578	/* millisecs to xfer 'len' bytes @ 'cur_speed' */
579	ms = xfer->len * 8 * 1000 / sdd->cur_speed;
580	ms += 30;               /* some tolerance */
581	ms = max(ms, 100);      /* minimum timeout */
582
583	val = msecs_to_jiffies(ms) + 10;
584	val = wait_for_completion_timeout(&sdd->xfer_completion, val);
585
586	/*
587	 * If the previous xfer was completed within timeout, then
588	 * proceed further else return -ETIMEDOUT.
589	 * DmaTx returns after simply writing data in the FIFO,
590	 * w/o waiting for real transmission on the bus to finish.
591	 * DmaRx returns only after Dma read data from FIFO which
592	 * needs bus transmission to finish, so we don't worry if
593	 * Xfer involved Rx(with or without Tx).
594	 */
595	if (val && !xfer->rx_buf) {
596		val = msecs_to_loops(10);
597		status = readl(regs + S3C64XX_SPI_STATUS);
598		while ((TX_FIFO_LVL(status, sdd)
599			|| !S3C64XX_SPI_ST_TX_DONE(status, sdd))
600		       && --val) {
601			cpu_relax();
602			status = readl(regs + S3C64XX_SPI_STATUS);
603		}
604
605	}
606
607	/* If timed out while checking rx/tx status return error */
608	if (!val)
609		return -ETIMEDOUT;
610
611	return 0;
612}
613
614static int s3c64xx_wait_for_pio(struct s3c64xx_spi_driver_data *sdd,
615				struct spi_transfer *xfer, bool use_irq)
616{
617	void __iomem *regs = sdd->regs;
618	unsigned long val;
619	u32 status;
620	int loops;
621	u32 cpy_len;
622	u8 *buf;
623	int ms;
624	unsigned long time_us;
625
626	/* microsecs to xfer 'len' bytes @ 'cur_speed' */
627	time_us = (xfer->len * 8 * 1000 * 1000) / sdd->cur_speed;
628	ms = (time_us / 1000);
629	ms += 10; /* some tolerance */
630
631	/* sleep during signal transfer time */
632	status = readl(regs + S3C64XX_SPI_STATUS);
633	if (RX_FIFO_LVL(status, sdd) < xfer->len)
634		usleep_range(time_us / 2, time_us);
635
636	if (use_irq) {
637		val = msecs_to_jiffies(ms);
638		if (!wait_for_completion_timeout(&sdd->xfer_completion, val))
639			return -ETIMEDOUT;
640	}
641
642	val = msecs_to_loops(ms);
643	do {
644		status = readl(regs + S3C64XX_SPI_STATUS);
645	} while (RX_FIFO_LVL(status, sdd) < xfer->len && --val);
646
647	if (!val)
648		return -EIO;
649
650	/* If it was only Tx */
651	if (!xfer->rx_buf) {
652		sdd->state &= ~TXBUSY;
653		return 0;
654	}
655
656	/*
657	 * If the receive length is bigger than the controller fifo
658	 * size, calculate the loops and read the fifo as many times.
659	 * loops = length / max fifo size (calculated by using the
660	 * fifo mask).
661	 * For any size less than the fifo size the below code is
662	 * executed atleast once.
663	 */
664	loops = xfer->len / sdd->fifo_depth;
665	buf = xfer->rx_buf;
666	do {
667		/* wait for data to be received in the fifo */
668		cpy_len = s3c64xx_spi_wait_for_timeout(sdd,
669						       (loops ? ms : 0));
670
671		switch (sdd->cur_bpw) {
672		case 32:
673			ioread32_rep(regs + S3C64XX_SPI_RX_DATA,
674				     buf, cpy_len / 4);
675			break;
676		case 16:
677			ioread16_rep(regs + S3C64XX_SPI_RX_DATA,
678				     buf, cpy_len / 2);
679			break;
680		default:
681			ioread8_rep(regs + S3C64XX_SPI_RX_DATA,
682				    buf, cpy_len);
683			break;
684		}
685
686		buf = buf + cpy_len;
687	} while (loops--);
688	sdd->state &= ~RXBUSY;
689
690	return 0;
691}
692
693static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
694{
695	void __iomem *regs = sdd->regs;
696	int ret;
697	u32 val;
698	int div = sdd->port_conf->clk_div;
699
700	/* Disable Clock */
701	if (!sdd->port_conf->clk_from_cmu) {
702		val = readl(regs + S3C64XX_SPI_CLK_CFG);
703		val &= ~S3C64XX_SPI_ENCLK_ENABLE;
704		writel(val, regs + S3C64XX_SPI_CLK_CFG);
705	}
706
707	/* Set Polarity and Phase */
708	val = readl(regs + S3C64XX_SPI_CH_CFG);
709	val &= ~(S3C64XX_SPI_CH_SLAVE |
710			S3C64XX_SPI_CPOL_L |
711			S3C64XX_SPI_CPHA_B);
712
713	if (sdd->cur_mode & SPI_CPOL)
714		val |= S3C64XX_SPI_CPOL_L;
715
716	if (sdd->cur_mode & SPI_CPHA)
717		val |= S3C64XX_SPI_CPHA_B;
718
719	writel(val, regs + S3C64XX_SPI_CH_CFG);
720
721	/* Set Channel & DMA Mode */
722	val = readl(regs + S3C64XX_SPI_MODE_CFG);
723	val &= ~(S3C64XX_SPI_MODE_BUS_TSZ_MASK
724			| S3C64XX_SPI_MODE_CH_TSZ_MASK);
725
726	switch (sdd->cur_bpw) {
727	case 32:
728		val |= S3C64XX_SPI_MODE_BUS_TSZ_WORD;
729		val |= S3C64XX_SPI_MODE_CH_TSZ_WORD;
730		break;
731	case 16:
732		val |= S3C64XX_SPI_MODE_BUS_TSZ_HALFWORD;
733		val |= S3C64XX_SPI_MODE_CH_TSZ_HALFWORD;
734		break;
735	default:
736		val |= S3C64XX_SPI_MODE_BUS_TSZ_BYTE;
737		val |= S3C64XX_SPI_MODE_CH_TSZ_BYTE;
738		break;
739	}
740
741	if ((sdd->cur_mode & SPI_LOOP) && sdd->port_conf->has_loopback)
742		val |= S3C64XX_SPI_MODE_SELF_LOOPBACK;
743	else
744		val &= ~S3C64XX_SPI_MODE_SELF_LOOPBACK;
745
746	writel(val, regs + S3C64XX_SPI_MODE_CFG);
747
748	if (sdd->port_conf->clk_from_cmu) {
749		ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * div);
750		if (ret)
751			return ret;
752		sdd->cur_speed = clk_get_rate(sdd->src_clk) / div;
753	} else {
754		/* Configure Clock */
755		val = readl(regs + S3C64XX_SPI_CLK_CFG);
756		val &= ~S3C64XX_SPI_PSR_MASK;
757		val |= ((clk_get_rate(sdd->src_clk) / sdd->cur_speed / div - 1)
758				& S3C64XX_SPI_PSR_MASK);
759		writel(val, regs + S3C64XX_SPI_CLK_CFG);
760
761		/* Enable Clock */
762		val = readl(regs + S3C64XX_SPI_CLK_CFG);
763		val |= S3C64XX_SPI_ENCLK_ENABLE;
764		writel(val, regs + S3C64XX_SPI_CLK_CFG);
765	}
766
767	return 0;
768}
769
770#define XFER_DMAADDR_INVALID DMA_BIT_MASK(32)
771
772static int s3c64xx_spi_prepare_message(struct spi_controller *host,
773				       struct spi_message *msg)
774{
775	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
776	struct spi_device *spi = msg->spi;
777	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
778
779	/* Configure feedback delay */
780	if (!cs)
781		/* No delay if not defined */
782		writel(0, sdd->regs + S3C64XX_SPI_FB_CLK);
783	else
784		writel(cs->fb_delay & 0x3, sdd->regs + S3C64XX_SPI_FB_CLK);
785
786	return 0;
787}
788
789static size_t s3c64xx_spi_max_transfer_size(struct spi_device *spi)
790{
791	struct spi_controller *ctlr = spi->controller;
792
793	return ctlr->can_dma ? S3C64XX_SPI_PACKET_CNT_MASK : SIZE_MAX;
794}
795
796static int s3c64xx_spi_transfer_one(struct spi_controller *host,
797				    struct spi_device *spi,
798				    struct spi_transfer *xfer)
799{
800	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
801	const unsigned int fifo_len = sdd->fifo_depth;
802	const void *tx_buf = NULL;
803	void *rx_buf = NULL;
804	int target_len = 0, origin_len = 0;
805	int use_dma = 0;
806	bool use_irq = false;
807	int status;
808	u32 speed;
809	u8 bpw;
810	unsigned long flags;
811	u32 rdy_lv;
812	u32 val;
813
814	reinit_completion(&sdd->xfer_completion);
815
816	/* Only BPW and Speed may change across transfers */
817	bpw = xfer->bits_per_word;
818	speed = xfer->speed_hz;
819
820	if (bpw != sdd->cur_bpw || speed != sdd->cur_speed) {
821		sdd->cur_bpw = bpw;
822		sdd->cur_speed = speed;
823		sdd->cur_mode = spi->mode;
824		status = s3c64xx_spi_config(sdd);
825		if (status)
826			return status;
827	}
828
829	if (!is_polling(sdd) && xfer->len >= fifo_len &&
830	    sdd->rx_dma.ch && sdd->tx_dma.ch) {
831		use_dma = 1;
832	} else if (xfer->len >= fifo_len) {
833		tx_buf = xfer->tx_buf;
834		rx_buf = xfer->rx_buf;
835		origin_len = xfer->len;
836		target_len = xfer->len;
837		xfer->len = fifo_len - 1;
838	}
839
840	do {
841		/* transfer size is greater than 32, change to IRQ mode */
842		if (!use_dma && xfer->len > S3C64XX_SPI_POLLING_SIZE)
843			use_irq = true;
844
845		if (use_irq) {
846			reinit_completion(&sdd->xfer_completion);
847
848			rdy_lv = xfer->len;
849			/* Setup RDY_FIFO trigger Level
850			 * RDY_LVL =
851			 * fifo_lvl up to 64 byte -> N bytes
852			 *               128 byte -> RDY_LVL * 2 bytes
853			 *               256 byte -> RDY_LVL * 4 bytes
854			 */
855			if (fifo_len == 128)
856				rdy_lv /= 2;
857			else if (fifo_len == 256)
858				rdy_lv /= 4;
859
860			val = readl(sdd->regs + S3C64XX_SPI_MODE_CFG);
861			val &= ~S3C64XX_SPI_MODE_RX_RDY_LVL;
862			val |= (rdy_lv << S3C64XX_SPI_MODE_RX_RDY_LVL_SHIFT);
863			writel(val, sdd->regs + S3C64XX_SPI_MODE_CFG);
864
865			/* Enable FIFO_RDY_EN IRQ */
866			val = readl(sdd->regs + S3C64XX_SPI_INT_EN);
867			writel((val | S3C64XX_SPI_INT_RX_FIFORDY_EN),
868					sdd->regs + S3C64XX_SPI_INT_EN);
869
870		}
871
872		spin_lock_irqsave(&sdd->lock, flags);
873
874		/* Pending only which is to be done */
875		sdd->state &= ~RXBUSY;
876		sdd->state &= ~TXBUSY;
877
878		/* Start the signals */
879		s3c64xx_spi_set_cs(spi, true);
880
881		status = s3c64xx_enable_datapath(sdd, xfer, use_dma);
882
883		spin_unlock_irqrestore(&sdd->lock, flags);
884
885		if (status) {
886			dev_err(&spi->dev, "failed to enable data path for transfer: %d\n", status);
887			break;
888		}
889
890		if (use_dma)
891			status = s3c64xx_wait_for_dma(sdd, xfer);
892		else
893			status = s3c64xx_wait_for_pio(sdd, xfer, use_irq);
894
895		if (status) {
896			dev_err(&spi->dev,
897				"I/O Error: rx-%d tx-%d rx-%c tx-%c len-%d dma-%d res-(%d)\n",
898				xfer->rx_buf ? 1 : 0, xfer->tx_buf ? 1 : 0,
899				(sdd->state & RXBUSY) ? 'f' : 'p',
900				(sdd->state & TXBUSY) ? 'f' : 'p',
901				xfer->len, use_dma ? 1 : 0, status);
902
903			if (use_dma) {
904				struct dma_tx_state s;
905
906				if (xfer->tx_buf && (sdd->state & TXBUSY)) {
907					dmaengine_pause(sdd->tx_dma.ch);
908					dmaengine_tx_status(sdd->tx_dma.ch, sdd->tx_dma.cookie, &s);
909					dmaengine_terminate_all(sdd->tx_dma.ch);
910					dev_err(&spi->dev, "TX residue: %d\n", s.residue);
911
912				}
913				if (xfer->rx_buf && (sdd->state & RXBUSY)) {
914					dmaengine_pause(sdd->rx_dma.ch);
915					dmaengine_tx_status(sdd->rx_dma.ch, sdd->rx_dma.cookie, &s);
916					dmaengine_terminate_all(sdd->rx_dma.ch);
917					dev_err(&spi->dev, "RX residue: %d\n", s.residue);
918				}
919			}
920		} else {
921			s3c64xx_flush_fifo(sdd);
922		}
923		if (target_len > 0) {
924			target_len -= xfer->len;
925
926			if (xfer->tx_buf)
927				xfer->tx_buf += xfer->len;
928
929			if (xfer->rx_buf)
930				xfer->rx_buf += xfer->len;
931
932			if (target_len >= fifo_len)
933				xfer->len = fifo_len - 1;
934			else
935				xfer->len = target_len;
936		}
937	} while (target_len > 0);
938
939	if (origin_len) {
940		/* Restore original xfer buffers and length */
941		xfer->tx_buf = tx_buf;
942		xfer->rx_buf = rx_buf;
943		xfer->len = origin_len;
944	}
945
946	return status;
947}
948
949static struct s3c64xx_spi_csinfo *s3c64xx_get_target_ctrldata(
950				struct spi_device *spi)
951{
952	struct s3c64xx_spi_csinfo *cs;
953	struct device_node *target_np, *data_np = NULL;
954	u32 fb_delay = 0;
955
956	target_np = spi->dev.of_node;
957	if (!target_np) {
958		dev_err(&spi->dev, "device node not found\n");
959		return ERR_PTR(-EINVAL);
960	}
961
962	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
963	if (!cs)
964		return ERR_PTR(-ENOMEM);
965
966	data_np = of_get_child_by_name(target_np, "controller-data");
967	if (!data_np) {
968		dev_info(&spi->dev, "feedback delay set to default (0)\n");
969		return cs;
970	}
971
972	of_property_read_u32(data_np, "samsung,spi-feedback-delay", &fb_delay);
973	cs->fb_delay = fb_delay;
974	of_node_put(data_np);
975	return cs;
976}
977
978/*
979 * Here we only check the validity of requested configuration
980 * and save the configuration in a local data-structure.
981 * The controller is actually configured only just before we
982 * get a message to transfer.
983 */
984static int s3c64xx_spi_setup(struct spi_device *spi)
985{
986	struct s3c64xx_spi_csinfo *cs = spi->controller_data;
987	struct s3c64xx_spi_driver_data *sdd;
988	int err;
989	int div;
990
991	sdd = spi_controller_get_devdata(spi->controller);
992	if (spi->dev.of_node) {
993		cs = s3c64xx_get_target_ctrldata(spi);
994		spi->controller_data = cs;
995	}
996
997	/* NULL is fine, we just avoid using the FB delay (=0) */
998	if (IS_ERR(cs)) {
999		dev_err(&spi->dev, "No CS for SPI(%d)\n", spi_get_chipselect(spi, 0));
1000		return -ENODEV;
1001	}
1002
1003	if (!spi_get_ctldata(spi))
1004		spi_set_ctldata(spi, cs);
1005
1006	pm_runtime_get_sync(&sdd->pdev->dev);
1007
1008	div = sdd->port_conf->clk_div;
1009
1010	/* Check if we can provide the requested rate */
1011	if (!sdd->port_conf->clk_from_cmu) {
1012		u32 psr, speed;
1013
1014		/* Max possible */
1015		speed = clk_get_rate(sdd->src_clk) / div / (0 + 1);
1016
1017		if (spi->max_speed_hz > speed)
1018			spi->max_speed_hz = speed;
1019
1020		psr = clk_get_rate(sdd->src_clk) / div / spi->max_speed_hz - 1;
1021		psr &= S3C64XX_SPI_PSR_MASK;
1022		if (psr == S3C64XX_SPI_PSR_MASK)
1023			psr--;
1024
1025		speed = clk_get_rate(sdd->src_clk) / div / (psr + 1);
1026		if (spi->max_speed_hz < speed) {
1027			if (psr+1 < S3C64XX_SPI_PSR_MASK) {
1028				psr++;
1029			} else {
1030				err = -EINVAL;
1031				goto setup_exit;
1032			}
1033		}
1034
1035		speed = clk_get_rate(sdd->src_clk) / div / (psr + 1);
1036		if (spi->max_speed_hz >= speed) {
1037			spi->max_speed_hz = speed;
1038		} else {
1039			dev_err(&spi->dev, "Can't set %dHz transfer speed\n",
1040				spi->max_speed_hz);
1041			err = -EINVAL;
1042			goto setup_exit;
1043		}
1044	}
1045
1046	pm_runtime_mark_last_busy(&sdd->pdev->dev);
1047	pm_runtime_put_autosuspend(&sdd->pdev->dev);
1048	s3c64xx_spi_set_cs(spi, false);
1049
1050	return 0;
1051
1052setup_exit:
1053	pm_runtime_mark_last_busy(&sdd->pdev->dev);
1054	pm_runtime_put_autosuspend(&sdd->pdev->dev);
1055	/* setup() returns with device de-selected */
1056	s3c64xx_spi_set_cs(spi, false);
1057
1058	spi_set_ctldata(spi, NULL);
1059
1060	/* This was dynamically allocated on the DT path */
1061	if (spi->dev.of_node)
1062		kfree(cs);
1063
1064	return err;
1065}
1066
1067static void s3c64xx_spi_cleanup(struct spi_device *spi)
1068{
1069	struct s3c64xx_spi_csinfo *cs = spi_get_ctldata(spi);
1070
1071	/* This was dynamically allocated on the DT path */
1072	if (spi->dev.of_node)
1073		kfree(cs);
1074
1075	spi_set_ctldata(spi, NULL);
1076}
1077
1078static irqreturn_t s3c64xx_spi_irq(int irq, void *data)
1079{
1080	struct s3c64xx_spi_driver_data *sdd = data;
1081	struct spi_controller *spi = sdd->host;
1082	unsigned int val, clr = 0;
1083
1084	val = readl(sdd->regs + S3C64XX_SPI_STATUS);
1085
1086	if (val & S3C64XX_SPI_ST_RX_OVERRUN_ERR) {
1087		clr = S3C64XX_SPI_PND_RX_OVERRUN_CLR;
1088		dev_err(&spi->dev, "RX overrun\n");
1089	}
1090	if (val & S3C64XX_SPI_ST_RX_UNDERRUN_ERR) {
1091		clr |= S3C64XX_SPI_PND_RX_UNDERRUN_CLR;
1092		dev_err(&spi->dev, "RX underrun\n");
1093	}
1094	if (val & S3C64XX_SPI_ST_TX_OVERRUN_ERR) {
1095		clr |= S3C64XX_SPI_PND_TX_OVERRUN_CLR;
1096		dev_err(&spi->dev, "TX overrun\n");
1097	}
1098	if (val & S3C64XX_SPI_ST_TX_UNDERRUN_ERR) {
1099		clr |= S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1100		dev_err(&spi->dev, "TX underrun\n");
1101	}
1102
1103	if (val & S3C64XX_SPI_ST_RX_FIFORDY) {
1104		complete(&sdd->xfer_completion);
1105		/* No pending clear irq, turn-off INT_EN_RX_FIFO_RDY */
1106		val = readl(sdd->regs + S3C64XX_SPI_INT_EN);
1107		writel((val & ~S3C64XX_SPI_INT_RX_FIFORDY_EN),
1108				sdd->regs + S3C64XX_SPI_INT_EN);
1109	}
1110
1111	/* Clear the pending irq by setting and then clearing it */
1112	writel(clr, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1113	writel(0, sdd->regs + S3C64XX_SPI_PENDING_CLR);
1114
1115	return IRQ_HANDLED;
1116}
1117
1118static void s3c64xx_spi_hwinit(struct s3c64xx_spi_driver_data *sdd)
1119{
1120	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1121	void __iomem *regs = sdd->regs;
1122	unsigned int val;
1123
1124	sdd->cur_speed = 0;
1125
1126	if (sci->no_cs)
1127		writel(0, sdd->regs + S3C64XX_SPI_CS_REG);
1128	else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
1129		writel(S3C64XX_SPI_CS_SIG_INACT, sdd->regs + S3C64XX_SPI_CS_REG);
1130
1131	/* Disable Interrupts - we use Polling if not DMA mode */
1132	writel(0, regs + S3C64XX_SPI_INT_EN);
1133
1134	if (!sdd->port_conf->clk_from_cmu)
1135		writel(sci->src_clk_nr << S3C64XX_SPI_CLKSEL_SRCSHFT,
1136				regs + S3C64XX_SPI_CLK_CFG);
1137	writel(0, regs + S3C64XX_SPI_MODE_CFG);
1138	writel(0, regs + S3C64XX_SPI_PACKET_CNT);
1139
1140	/* Clear any irq pending bits, should set and clear the bits */
1141	val = S3C64XX_SPI_PND_RX_OVERRUN_CLR |
1142		S3C64XX_SPI_PND_RX_UNDERRUN_CLR |
1143		S3C64XX_SPI_PND_TX_OVERRUN_CLR |
1144		S3C64XX_SPI_PND_TX_UNDERRUN_CLR;
1145	writel(val, regs + S3C64XX_SPI_PENDING_CLR);
1146	writel(0, regs + S3C64XX_SPI_PENDING_CLR);
1147
1148	writel(0, regs + S3C64XX_SPI_SWAP_CFG);
1149
1150	val = readl(regs + S3C64XX_SPI_MODE_CFG);
1151	val &= ~S3C64XX_SPI_MODE_4BURST;
1152	val |= (S3C64XX_SPI_MAX_TRAILCNT << S3C64XX_SPI_TRAILCNT_OFF);
1153	writel(val, regs + S3C64XX_SPI_MODE_CFG);
1154
1155	s3c64xx_flush_fifo(sdd);
1156}
1157
1158#ifdef CONFIG_OF
1159static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1160{
1161	struct s3c64xx_spi_info *sci;
1162	u32 temp;
1163
1164	sci = devm_kzalloc(dev, sizeof(*sci), GFP_KERNEL);
1165	if (!sci)
1166		return ERR_PTR(-ENOMEM);
1167
1168	if (of_property_read_u32(dev->of_node, "samsung,spi-src-clk", &temp)) {
1169		dev_dbg(dev, "spi bus clock parent not specified, using clock at index 0 as parent\n");
1170		sci->src_clk_nr = 0;
1171	} else {
1172		sci->src_clk_nr = temp;
1173	}
1174
1175	if (of_property_read_u32(dev->of_node, "num-cs", &temp)) {
1176		dev_dbg(dev, "number of chip select lines not specified, assuming 1 chip select line\n");
1177		sci->num_cs = 1;
1178	} else {
1179		sci->num_cs = temp;
1180	}
1181
1182	sci->no_cs = of_property_read_bool(dev->of_node, "no-cs-readback");
1183	sci->polling = !of_property_present(dev->of_node, "dmas");
1184
1185	return sci;
1186}
1187#else
1188static struct s3c64xx_spi_info *s3c64xx_spi_parse_dt(struct device *dev)
1189{
1190	return dev_get_platdata(dev);
1191}
1192#endif
1193
1194static inline const struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
1195						struct platform_device *pdev)
1196{
1197#ifdef CONFIG_OF
1198	if (pdev->dev.of_node)
1199		return of_device_get_match_data(&pdev->dev);
1200#endif
1201	return (const struct s3c64xx_spi_port_config *)platform_get_device_id(pdev)->driver_data;
1202}
1203
1204static int s3c64xx_spi_set_port_id(struct platform_device *pdev,
1205				   struct s3c64xx_spi_driver_data *sdd)
1206{
1207	const struct s3c64xx_spi_port_config *port_conf = sdd->port_conf;
1208	int ret;
1209
1210	if (port_conf->rx_fifomask && port_conf->tx_fifomask)
1211		return 0;
1212
1213	if (pdev->dev.of_node) {
1214		ret = of_alias_get_id(pdev->dev.of_node, "spi");
1215		if (ret < 0)
1216			return dev_err_probe(&pdev->dev, ret,
1217					     "Failed to get alias id\n");
1218		sdd->port_id = ret;
1219	} else {
1220		if (pdev->id < 0)
1221			return dev_err_probe(&pdev->dev, -EINVAL,
1222					     "Negative platform ID is not allowed\n");
1223		sdd->port_id = pdev->id;
1224	}
1225
1226	return 0;
1227}
1228
1229static void s3c64xx_spi_set_fifomask(struct s3c64xx_spi_driver_data *sdd)
1230{
1231	const struct s3c64xx_spi_port_config *port_conf = sdd->port_conf;
1232
1233	if (port_conf->rx_fifomask)
1234		sdd->rx_fifomask = port_conf->rx_fifomask;
1235	else
1236		sdd->rx_fifomask = FIFO_LVL_MASK(sdd) <<
1237			port_conf->rx_lvl_offset;
1238
1239	if (port_conf->tx_fifomask)
1240		sdd->tx_fifomask = port_conf->tx_fifomask;
1241	else
1242		sdd->tx_fifomask = FIFO_LVL_MASK(sdd) <<
1243			S3C64XX_SPI_ST_TX_FIFO_LVL_SHIFT;
1244}
1245
1246static int s3c64xx_spi_probe(struct platform_device *pdev)
1247{
1248	struct resource	*mem_res;
1249	struct s3c64xx_spi_driver_data *sdd;
1250	struct s3c64xx_spi_info *sci = dev_get_platdata(&pdev->dev);
1251	struct spi_controller *host;
1252	int ret, irq;
1253	char clk_name[16];
1254
1255	if (!sci && pdev->dev.of_node) {
1256		sci = s3c64xx_spi_parse_dt(&pdev->dev);
1257		if (IS_ERR(sci))
1258			return PTR_ERR(sci);
1259	}
1260
1261	if (!sci)
1262		return dev_err_probe(&pdev->dev, -ENODEV,
1263				     "Platform_data missing!\n");
1264
1265	irq = platform_get_irq(pdev, 0);
1266	if (irq < 0)
1267		return irq;
1268
1269	host = devm_spi_alloc_host(&pdev->dev, sizeof(*sdd));
1270	if (!host)
1271		return dev_err_probe(&pdev->dev, -ENOMEM,
1272				     "Unable to allocate SPI Host\n");
1273
1274	platform_set_drvdata(pdev, host);
1275
1276	sdd = spi_controller_get_devdata(host);
1277	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
1278	sdd->host = host;
1279	sdd->cntrlr_info = sci;
1280	sdd->pdev = pdev;
1281
1282	ret = s3c64xx_spi_set_port_id(pdev, sdd);
1283	if (ret)
1284		return ret;
1285
1286	if (sdd->port_conf->fifo_depth)
1287		sdd->fifo_depth = sdd->port_conf->fifo_depth;
1288	else if (of_property_read_u32(pdev->dev.of_node, "fifo-depth",
1289				      &sdd->fifo_depth))
1290		sdd->fifo_depth = FIFO_DEPTH(sdd);
1291
1292	s3c64xx_spi_set_fifomask(sdd);
1293
1294	sdd->cur_bpw = 8;
1295
1296	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
1297	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
1298
1299	host->dev.of_node = pdev->dev.of_node;
1300	host->bus_num = -1;
1301	host->setup = s3c64xx_spi_setup;
1302	host->cleanup = s3c64xx_spi_cleanup;
1303	host->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
1304	host->unprepare_transfer_hardware = s3c64xx_spi_unprepare_transfer;
1305	host->prepare_message = s3c64xx_spi_prepare_message;
1306	host->transfer_one = s3c64xx_spi_transfer_one;
1307	host->max_transfer_size = s3c64xx_spi_max_transfer_size;
1308	host->num_chipselect = sci->num_cs;
1309	host->use_gpio_descriptors = true;
1310	host->dma_alignment = 8;
1311	host->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
1312				   SPI_BPW_MASK(8);
1313	/* the spi->mode bits understood by this driver: */
1314	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1315	if (sdd->port_conf->has_loopback)
1316		host->mode_bits |= SPI_LOOP;
1317	host->auto_runtime_pm = true;
1318	if (!is_polling(sdd))
1319		host->can_dma = s3c64xx_spi_can_dma;
1320
1321	sdd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &mem_res);
1322	if (IS_ERR(sdd->regs))
1323		return PTR_ERR(sdd->regs);
1324	sdd->sfr_start = mem_res->start;
1325
1326	if (sci->cfg_gpio && sci->cfg_gpio())
1327		return dev_err_probe(&pdev->dev, -EBUSY,
1328				     "Unable to config gpio\n");
1329
1330	/* Setup clocks */
1331	sdd->clk = devm_clk_get_enabled(&pdev->dev, "spi");
1332	if (IS_ERR(sdd->clk))
1333		return dev_err_probe(&pdev->dev, PTR_ERR(sdd->clk),
1334				     "Unable to acquire clock 'spi'\n");
1335
1336	sprintf(clk_name, "spi_busclk%d", sci->src_clk_nr);
1337	sdd->src_clk = devm_clk_get_enabled(&pdev->dev, clk_name);
1338	if (IS_ERR(sdd->src_clk))
1339		return dev_err_probe(&pdev->dev, PTR_ERR(sdd->src_clk),
1340				     "Unable to acquire clock '%s'\n",
1341				     clk_name);
1342
1343	if (sdd->port_conf->clk_ioclk) {
1344		sdd->ioclk = devm_clk_get_enabled(&pdev->dev, "spi_ioclk");
1345		if (IS_ERR(sdd->ioclk))
1346			return dev_err_probe(&pdev->dev, PTR_ERR(sdd->ioclk),
1347					     "Unable to acquire 'ioclk'\n");
1348	}
1349
1350	pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
1351	pm_runtime_use_autosuspend(&pdev->dev);
1352	pm_runtime_set_active(&pdev->dev);
1353	pm_runtime_enable(&pdev->dev);
1354	pm_runtime_get_sync(&pdev->dev);
1355
1356	/* Setup Deufult Mode */
1357	s3c64xx_spi_hwinit(sdd);
1358
1359	spin_lock_init(&sdd->lock);
1360	init_completion(&sdd->xfer_completion);
1361
1362	ret = devm_request_irq(&pdev->dev, irq, s3c64xx_spi_irq, 0,
1363				"spi-s3c64xx", sdd);
1364	if (ret != 0) {
1365		dev_err(&pdev->dev, "Failed to request IRQ %d: %d\n",
1366			irq, ret);
1367		goto err_pm_put;
1368	}
1369
1370	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1371	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1372	       sdd->regs + S3C64XX_SPI_INT_EN);
1373
1374	ret = devm_spi_register_controller(&pdev->dev, host);
1375	if (ret != 0) {
1376		dev_err(&pdev->dev, "cannot register SPI host: %d\n", ret);
1377		goto err_pm_put;
1378	}
1379
1380	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Targets attached\n",
1381		host->bus_num, host->num_chipselect);
1382	dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\n",
1383		mem_res, sdd->fifo_depth);
1384
1385	pm_runtime_mark_last_busy(&pdev->dev);
1386	pm_runtime_put_autosuspend(&pdev->dev);
1387
1388	return 0;
1389
1390err_pm_put:
1391	pm_runtime_put_noidle(&pdev->dev);
1392	pm_runtime_disable(&pdev->dev);
1393	pm_runtime_set_suspended(&pdev->dev);
1394
1395	return ret;
1396}
1397
1398static void s3c64xx_spi_remove(struct platform_device *pdev)
1399{
1400	struct spi_controller *host = platform_get_drvdata(pdev);
1401	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1402
1403	pm_runtime_get_sync(&pdev->dev);
1404
1405	writel(0, sdd->regs + S3C64XX_SPI_INT_EN);
1406
1407	if (!is_polling(sdd)) {
1408		dma_release_channel(sdd->rx_dma.ch);
1409		dma_release_channel(sdd->tx_dma.ch);
1410	}
1411
1412	pm_runtime_put_noidle(&pdev->dev);
1413	pm_runtime_disable(&pdev->dev);
1414	pm_runtime_set_suspended(&pdev->dev);
1415}
1416
1417#ifdef CONFIG_PM_SLEEP
1418static int s3c64xx_spi_suspend(struct device *dev)
1419{
1420	struct spi_controller *host = dev_get_drvdata(dev);
1421	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1422	int ret;
1423
1424	ret = spi_controller_suspend(host);
1425	if (ret)
1426		return ret;
1427
1428	ret = pm_runtime_force_suspend(dev);
1429	if (ret < 0)
1430		return ret;
1431
1432	sdd->cur_speed = 0; /* Output Clock is stopped */
1433
1434	return 0;
1435}
1436
1437static int s3c64xx_spi_resume(struct device *dev)
1438{
1439	struct spi_controller *host = dev_get_drvdata(dev);
1440	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1441	struct s3c64xx_spi_info *sci = sdd->cntrlr_info;
1442	int ret;
1443
1444	if (sci->cfg_gpio)
1445		sci->cfg_gpio();
1446
1447	ret = pm_runtime_force_resume(dev);
1448	if (ret < 0)
1449		return ret;
1450
1451	return spi_controller_resume(host);
1452}
1453#endif /* CONFIG_PM_SLEEP */
1454
1455#ifdef CONFIG_PM
1456static int s3c64xx_spi_runtime_suspend(struct device *dev)
1457{
1458	struct spi_controller *host = dev_get_drvdata(dev);
1459	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1460
1461	clk_disable_unprepare(sdd->clk);
1462	clk_disable_unprepare(sdd->src_clk);
1463	clk_disable_unprepare(sdd->ioclk);
1464
1465	return 0;
1466}
1467
1468static int s3c64xx_spi_runtime_resume(struct device *dev)
1469{
1470	struct spi_controller *host = dev_get_drvdata(dev);
1471	struct s3c64xx_spi_driver_data *sdd = spi_controller_get_devdata(host);
1472	int ret;
1473
1474	if (sdd->port_conf->clk_ioclk) {
1475		ret = clk_prepare_enable(sdd->ioclk);
1476		if (ret != 0)
1477			return ret;
1478	}
1479
1480	ret = clk_prepare_enable(sdd->src_clk);
1481	if (ret != 0)
1482		goto err_disable_ioclk;
1483
1484	ret = clk_prepare_enable(sdd->clk);
1485	if (ret != 0)
1486		goto err_disable_src_clk;
1487
1488	s3c64xx_spi_hwinit(sdd);
1489
1490	writel(S3C64XX_SPI_INT_RX_OVERRUN_EN | S3C64XX_SPI_INT_RX_UNDERRUN_EN |
1491	       S3C64XX_SPI_INT_TX_OVERRUN_EN | S3C64XX_SPI_INT_TX_UNDERRUN_EN,
1492	       sdd->regs + S3C64XX_SPI_INT_EN);
1493
1494	return 0;
1495
1496err_disable_src_clk:
1497	clk_disable_unprepare(sdd->src_clk);
1498err_disable_ioclk:
1499	clk_disable_unprepare(sdd->ioclk);
1500
1501	return ret;
1502}
1503#endif /* CONFIG_PM */
1504
1505static const struct dev_pm_ops s3c64xx_spi_pm = {
1506	SET_SYSTEM_SLEEP_PM_OPS(s3c64xx_spi_suspend, s3c64xx_spi_resume)
1507	SET_RUNTIME_PM_OPS(s3c64xx_spi_runtime_suspend,
1508			   s3c64xx_spi_runtime_resume, NULL)
1509};
1510
1511static const struct s3c64xx_spi_port_config s3c2443_spi_port_config = {
1512	/* fifo_lvl_mask is deprecated. Use {rx, tx}_fifomask instead. */
1513	.fifo_lvl_mask	= { 0x7f },
1514	/* rx_lvl_offset is deprecated. Use {rx, tx}_fifomask instead. */
1515	.rx_lvl_offset	= 13,
1516	.tx_st_done	= 21,
1517	.clk_div	= 2,
1518	.high_speed	= true,
1519};
1520
1521static const struct s3c64xx_spi_port_config s3c6410_spi_port_config = {
1522	/* fifo_lvl_mask is deprecated. Use {rx, tx}_fifomask instead. */
1523	.fifo_lvl_mask	= { 0x7f, 0x7F },
1524	/* rx_lvl_offset is deprecated. Use {rx, tx}_fifomask instead. */
1525	.rx_lvl_offset	= 13,
1526	.tx_st_done	= 21,
1527	.clk_div	= 2,
1528};
1529
1530static const struct s3c64xx_spi_port_config s5pv210_spi_port_config = {
1531	/* fifo_lvl_mask is deprecated. Use {rx, tx}_fifomask instead. */
1532	.fifo_lvl_mask	= { 0x1ff, 0x7F },
1533	/* rx_lvl_offset is deprecated. Use {rx, tx}_fifomask instead. */
1534	.rx_lvl_offset	= 15,
1535	.tx_st_done	= 25,
1536	.clk_div	= 2,
1537	.high_speed	= true,
1538};
1539
1540static const struct s3c64xx_spi_port_config exynos4_spi_port_config = {
1541	/* fifo_lvl_mask is deprecated. Use {rx, tx}_fifomask instead. */
1542	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F },
1543	/* rx_lvl_offset is deprecated. Use {rx, tx}_fifomask instead. */
1544	.rx_lvl_offset	= 15,
1545	.tx_st_done	= 25,
1546	.clk_div	= 2,
1547	.high_speed	= true,
1548	.clk_from_cmu	= true,
1549	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1550};
1551
1552static const struct s3c64xx_spi_port_config exynos7_spi_port_config = {
1553	/* fifo_lvl_mask is deprecated. Use {rx, tx}_fifomask instead. */
1554	.fifo_lvl_mask	= { 0x1ff, 0x7F, 0x7F, 0x7F, 0x7F, 0x1ff},
1555	/* rx_lvl_offset is deprecated. Use {rx, tx}_fifomask instead. */
1556	.rx_lvl_offset	= 15,
1557	.tx_st_done	= 25,
1558	.clk_div	= 2,
1559	.high_speed	= true,
1560	.clk_from_cmu	= true,
1561	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1562};
1563
1564static const struct s3c64xx_spi_port_config exynos5433_spi_port_config = {
1565	/* fifo_lvl_mask is deprecated. Use {rx, tx}_fifomask instead. */
1566	.fifo_lvl_mask	= { 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff},
1567	/* rx_lvl_offset is deprecated. Use {rx, tx}_fifomask instead. */
1568	.rx_lvl_offset	= 15,
1569	.tx_st_done	= 25,
1570	.clk_div	= 2,
1571	.high_speed	= true,
1572	.clk_from_cmu	= true,
1573	.clk_ioclk	= true,
1574	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1575};
1576
1577static const struct s3c64xx_spi_port_config exynos850_spi_port_config = {
1578	.fifo_depth	= 64,
1579	.rx_fifomask	= S3C64XX_SPI_ST_RX_FIFO_RDY_V2,
1580	.tx_fifomask	= S3C64XX_SPI_ST_TX_FIFO_RDY_V2,
1581	.tx_st_done	= 25,
1582	.clk_div	= 4,
1583	.high_speed	= true,
1584	.clk_from_cmu	= true,
1585	.has_loopback	= true,
1586	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1587};
1588
1589static const struct s3c64xx_spi_port_config exynosautov9_spi_port_config = {
1590	/* fifo_lvl_mask is deprecated. Use {rx, tx}_fifomask instead. */
1591	.fifo_lvl_mask	= { 0x1ff, 0x1ff, 0x7f, 0x7f, 0x7f, 0x7f, 0x1ff, 0x7f,
1592			    0x7f, 0x7f, 0x7f, 0x7f},
1593	/* rx_lvl_offset is deprecated. Use {rx, tx}_fifomask instead. */
1594	.rx_lvl_offset	= 15,
1595	.tx_st_done	= 25,
1596	.clk_div	= 4,
1597	.high_speed	= true,
1598	.clk_from_cmu	= true,
1599	.clk_ioclk	= true,
1600	.has_loopback	= true,
1601	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1602};
1603
1604static const struct s3c64xx_spi_port_config fsd_spi_port_config = {
1605	/* fifo_lvl_mask is deprecated. Use {rx, tx}_fifomask instead. */
1606	.fifo_lvl_mask	= { 0x7f, 0x7f, 0x7f, 0x7f, 0x7f},
1607	/* rx_lvl_offset is deprecated. Use {rx, tx}_fifomask instead. */
1608	.rx_lvl_offset	= 15,
1609	.tx_st_done	= 25,
1610	.clk_div	= 2,
1611	.high_speed	= true,
1612	.clk_from_cmu	= true,
1613	.clk_ioclk	= false,
1614	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1615};
1616
1617static const struct s3c64xx_spi_port_config gs101_spi_port_config = {
1618	.fifo_depth	= 64,
1619	.rx_fifomask	= S3C64XX_SPI_ST_RX_FIFO_RDY_V2,
1620	.tx_fifomask	= S3C64XX_SPI_ST_TX_FIFO_RDY_V2,
1621	.tx_st_done	= 25,
1622	.clk_div	= 4,
1623	.high_speed	= true,
1624	.clk_from_cmu	= true,
1625	.has_loopback	= true,
1626	.use_32bit_io	= true,
1627	.quirks		= S3C64XX_SPI_QUIRK_CS_AUTO,
1628};
1629
1630static const struct platform_device_id s3c64xx_spi_driver_ids[] = {
1631	{
1632		.name		= "s3c2443-spi",
1633		.driver_data	= (kernel_ulong_t)&s3c2443_spi_port_config,
1634	}, {
1635		.name		= "s3c6410-spi",
1636		.driver_data	= (kernel_ulong_t)&s3c6410_spi_port_config,
1637	},
1638	{ },
1639};
1640
1641static const struct of_device_id s3c64xx_spi_dt_match[] = {
1642	{ .compatible = "google,gs101-spi",
1643			.data = &gs101_spi_port_config,
1644	},
1645	{ .compatible = "samsung,s3c2443-spi",
1646			.data = &s3c2443_spi_port_config,
1647	},
1648	{ .compatible = "samsung,s3c6410-spi",
1649			.data = &s3c6410_spi_port_config,
1650	},
1651	{ .compatible = "samsung,s5pv210-spi",
1652			.data = &s5pv210_spi_port_config,
1653	},
1654	{ .compatible = "samsung,exynos4210-spi",
1655			.data = &exynos4_spi_port_config,
1656	},
1657	{ .compatible = "samsung,exynos7-spi",
1658			.data = &exynos7_spi_port_config,
1659	},
1660	{ .compatible = "samsung,exynos5433-spi",
1661			.data = &exynos5433_spi_port_config,
1662	},
1663	{ .compatible = "samsung,exynos850-spi",
1664			.data = &exynos850_spi_port_config,
1665	},
1666	{ .compatible = "samsung,exynosautov9-spi",
1667			.data = &exynosautov9_spi_port_config,
1668	},
1669	{ .compatible = "tesla,fsd-spi",
1670			.data = &fsd_spi_port_config,
1671	},
1672	{ },
1673};
1674MODULE_DEVICE_TABLE(of, s3c64xx_spi_dt_match);
1675
1676static struct platform_driver s3c64xx_spi_driver = {
1677	.driver = {
1678		.name	= "s3c64xx-spi",
1679		.pm = &s3c64xx_spi_pm,
1680		.of_match_table = of_match_ptr(s3c64xx_spi_dt_match),
1681	},
1682	.probe = s3c64xx_spi_probe,
1683	.remove_new = s3c64xx_spi_remove,
1684	.id_table = s3c64xx_spi_driver_ids,
1685};
1686MODULE_ALIAS("platform:s3c64xx-spi");
1687
1688module_platform_driver(s3c64xx_spi_driver);
1689
1690MODULE_AUTHOR("Jaswinder Singh <jassi.brar@samsung.com>");
1691MODULE_DESCRIPTION("S3C64XX SPI Controller Driver");
1692MODULE_LICENSE("GPL");
1693