1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2013-2014 Renesas Electronics Europe Ltd.
4 * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
5 */
6
7#include <linux/clk.h>
8#include <linux/delay.h>
9#include <linux/device.h>
10#include <linux/dma-mapping.h>
11#include <linux/dmaengine.h>
12#include <linux/highmem.h>
13#include <linux/interrupt.h>
14#include <linux/io.h>
15#include <linux/log2.h>
16#include <linux/mmc/host.h>
17#include <linux/mmc/mmc.h>
18#include <linux/mmc/sd.h>
19#include <linux/mmc/sdio.h>
20#include <linux/module.h>
21#include <linux/pagemap.h>
22#include <linux/pinctrl/consumer.h>
23#include <linux/platform_device.h>
24#include <linux/scatterlist.h>
25#include <linux/string.h>
26#include <linux/time.h>
27#include <linux/virtio.h>
28#include <linux/workqueue.h>
29
30#define USDHI6_SD_CMD		0x0000
31#define USDHI6_SD_PORT_SEL	0x0004
32#define USDHI6_SD_ARG		0x0008
33#define USDHI6_SD_STOP		0x0010
34#define USDHI6_SD_SECCNT	0x0014
35#define USDHI6_SD_RSP10		0x0018
36#define USDHI6_SD_RSP32		0x0020
37#define USDHI6_SD_RSP54		0x0028
38#define USDHI6_SD_RSP76		0x0030
39#define USDHI6_SD_INFO1		0x0038
40#define USDHI6_SD_INFO2		0x003c
41#define USDHI6_SD_INFO1_MASK	0x0040
42#define USDHI6_SD_INFO2_MASK	0x0044
43#define USDHI6_SD_CLK_CTRL	0x0048
44#define USDHI6_SD_SIZE		0x004c
45#define USDHI6_SD_OPTION	0x0050
46#define USDHI6_SD_ERR_STS1	0x0058
47#define USDHI6_SD_ERR_STS2	0x005c
48#define USDHI6_SD_BUF0		0x0060
49#define USDHI6_SDIO_MODE	0x0068
50#define USDHI6_SDIO_INFO1	0x006c
51#define USDHI6_SDIO_INFO1_MASK	0x0070
52#define USDHI6_CC_EXT_MODE	0x01b0
53#define USDHI6_SOFT_RST		0x01c0
54#define USDHI6_VERSION		0x01c4
55#define USDHI6_HOST_MODE	0x01c8
56#define USDHI6_SDIF_MODE	0x01cc
57
58#define USDHI6_SD_CMD_APP		0x0040
59#define USDHI6_SD_CMD_MODE_RSP_AUTO	0x0000
60#define USDHI6_SD_CMD_MODE_RSP_NONE	0x0300
61#define USDHI6_SD_CMD_MODE_RSP_R1	0x0400	/* Also R5, R6, R7 */
62#define USDHI6_SD_CMD_MODE_RSP_R1B	0x0500	/* R1b */
63#define USDHI6_SD_CMD_MODE_RSP_R2	0x0600
64#define USDHI6_SD_CMD_MODE_RSP_R3	0x0700	/* Also R4 */
65#define USDHI6_SD_CMD_DATA		0x0800
66#define USDHI6_SD_CMD_READ		0x1000
67#define USDHI6_SD_CMD_MULTI		0x2000
68#define USDHI6_SD_CMD_CMD12_AUTO_OFF	0x4000
69
70#define USDHI6_CC_EXT_MODE_SDRW		BIT(1)
71
72#define USDHI6_SD_INFO1_RSP_END		BIT(0)
73#define USDHI6_SD_INFO1_ACCESS_END	BIT(2)
74#define USDHI6_SD_INFO1_CARD_OUT	BIT(3)
75#define USDHI6_SD_INFO1_CARD_IN		BIT(4)
76#define USDHI6_SD_INFO1_CD		BIT(5)
77#define USDHI6_SD_INFO1_WP		BIT(7)
78#define USDHI6_SD_INFO1_D3_CARD_OUT	BIT(8)
79#define USDHI6_SD_INFO1_D3_CARD_IN	BIT(9)
80
81#define USDHI6_SD_INFO2_CMD_ERR		BIT(0)
82#define USDHI6_SD_INFO2_CRC_ERR		BIT(1)
83#define USDHI6_SD_INFO2_END_ERR		BIT(2)
84#define USDHI6_SD_INFO2_TOUT		BIT(3)
85#define USDHI6_SD_INFO2_IWA_ERR		BIT(4)
86#define USDHI6_SD_INFO2_IRA_ERR		BIT(5)
87#define USDHI6_SD_INFO2_RSP_TOUT	BIT(6)
88#define USDHI6_SD_INFO2_SDDAT0		BIT(7)
89#define USDHI6_SD_INFO2_BRE		BIT(8)
90#define USDHI6_SD_INFO2_BWE		BIT(9)
91#define USDHI6_SD_INFO2_SCLKDIVEN	BIT(13)
92#define USDHI6_SD_INFO2_CBSY		BIT(14)
93#define USDHI6_SD_INFO2_ILA		BIT(15)
94
95#define USDHI6_SD_INFO1_CARD_INSERT (USDHI6_SD_INFO1_CARD_IN | USDHI6_SD_INFO1_D3_CARD_IN)
96#define USDHI6_SD_INFO1_CARD_EJECT (USDHI6_SD_INFO1_CARD_OUT | USDHI6_SD_INFO1_D3_CARD_OUT)
97#define USDHI6_SD_INFO1_CARD (USDHI6_SD_INFO1_CARD_INSERT | USDHI6_SD_INFO1_CARD_EJECT)
98#define USDHI6_SD_INFO1_CARD_CD (USDHI6_SD_INFO1_CARD_IN | USDHI6_SD_INFO1_CARD_OUT)
99
100#define USDHI6_SD_INFO2_ERR	(USDHI6_SD_INFO2_CMD_ERR |	\
101	USDHI6_SD_INFO2_CRC_ERR | USDHI6_SD_INFO2_END_ERR |	\
102	USDHI6_SD_INFO2_TOUT | USDHI6_SD_INFO2_IWA_ERR |	\
103	USDHI6_SD_INFO2_IRA_ERR | USDHI6_SD_INFO2_RSP_TOUT |	\
104	USDHI6_SD_INFO2_ILA)
105
106#define USDHI6_SD_INFO1_IRQ	(USDHI6_SD_INFO1_RSP_END | USDHI6_SD_INFO1_ACCESS_END | \
107				 USDHI6_SD_INFO1_CARD)
108
109#define USDHI6_SD_INFO2_IRQ	(USDHI6_SD_INFO2_ERR | USDHI6_SD_INFO2_BRE | \
110				 USDHI6_SD_INFO2_BWE | 0x0800 | USDHI6_SD_INFO2_ILA)
111
112#define USDHI6_SD_CLK_CTRL_SCLKEN	BIT(8)
113
114#define USDHI6_SD_STOP_STP		BIT(0)
115#define USDHI6_SD_STOP_SEC		BIT(8)
116
117#define USDHI6_SDIO_INFO1_IOIRQ		BIT(0)
118#define USDHI6_SDIO_INFO1_EXPUB52	BIT(14)
119#define USDHI6_SDIO_INFO1_EXWT		BIT(15)
120
121#define USDHI6_SD_ERR_STS1_CRC_NO_ERROR	BIT(13)
122
123#define USDHI6_SOFT_RST_RESERVED	(BIT(1) | BIT(2))
124#define USDHI6_SOFT_RST_RESET		BIT(0)
125
126#define USDHI6_SD_OPTION_TIMEOUT_SHIFT	4
127#define USDHI6_SD_OPTION_TIMEOUT_MASK	(0xf << USDHI6_SD_OPTION_TIMEOUT_SHIFT)
128#define USDHI6_SD_OPTION_WIDTH_1	BIT(15)
129
130#define USDHI6_SD_PORT_SEL_PORTS_SHIFT	8
131
132#define USDHI6_SD_CLK_CTRL_DIV_MASK	0xff
133
134#define USDHI6_SDIO_INFO1_IRQ	(USDHI6_SDIO_INFO1_IOIRQ | 3 | \
135				 USDHI6_SDIO_INFO1_EXPUB52 | USDHI6_SDIO_INFO1_EXWT)
136
137#define USDHI6_MIN_DMA 64
138
139#define USDHI6_REQ_TIMEOUT_MS 4000
140
141enum usdhi6_wait_for {
142	USDHI6_WAIT_FOR_REQUEST,
143	USDHI6_WAIT_FOR_CMD,
144	USDHI6_WAIT_FOR_MREAD,
145	USDHI6_WAIT_FOR_MWRITE,
146	USDHI6_WAIT_FOR_READ,
147	USDHI6_WAIT_FOR_WRITE,
148	USDHI6_WAIT_FOR_DATA_END,
149	USDHI6_WAIT_FOR_STOP,
150	USDHI6_WAIT_FOR_DMA,
151};
152
153struct usdhi6_page {
154	struct page *page;
155	void *mapped;		/* mapped page */
156};
157
158struct usdhi6_host {
159	struct mmc_host *mmc;
160	struct mmc_request *mrq;
161	void __iomem *base;
162	struct clk *clk;
163
164	/* SG memory handling */
165
166	/* Common for multiple and single block requests */
167	struct usdhi6_page pg;	/* current page from an SG */
168	void *blk_page;		/* either a mapped page, or the bounce buffer */
169	size_t offset;		/* offset within a page, including sg->offset */
170
171	/* Blocks, crossing a page boundary */
172	size_t head_len;
173	struct usdhi6_page head_pg;
174
175	/* A bounce buffer for unaligned blocks or blocks, crossing a page boundary */
176	struct scatterlist bounce_sg;
177	u8 bounce_buf[512];
178
179	/* Multiple block requests only */
180	struct scatterlist *sg;	/* current SG segment */
181	int page_idx;		/* page index within an SG segment */
182
183	enum usdhi6_wait_for wait;
184	u32 status_mask;
185	u32 status2_mask;
186	u32 sdio_mask;
187	u32 io_error;
188	u32 irq_status;
189	unsigned long imclk;
190	unsigned long rate;
191	bool app_cmd;
192
193	/* Timeout handling */
194	struct delayed_work timeout_work;
195	unsigned long timeout;
196
197	/* DMA support */
198	struct dma_chan *chan_rx;
199	struct dma_chan *chan_tx;
200	bool dma_active;
201
202	/* Pin control */
203	struct pinctrl *pinctrl;
204	struct pinctrl_state *pins_uhs;
205};
206
207/*			I/O primitives					*/
208
209static void usdhi6_write(struct usdhi6_host *host, u32 reg, u32 data)
210{
211	iowrite32(data, host->base + reg);
212	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
213		host->base, reg, data);
214}
215
216static void usdhi6_write16(struct usdhi6_host *host, u32 reg, u16 data)
217{
218	iowrite16(data, host->base + reg);
219	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
220		host->base, reg, data);
221}
222
223static u32 usdhi6_read(struct usdhi6_host *host, u32 reg)
224{
225	u32 data = ioread32(host->base + reg);
226	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
227		host->base, reg, data);
228	return data;
229}
230
231static u16 usdhi6_read16(struct usdhi6_host *host, u32 reg)
232{
233	u16 data = ioread16(host->base + reg);
234	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
235		host->base, reg, data);
236	return data;
237}
238
239static void usdhi6_irq_enable(struct usdhi6_host *host, u32 info1, u32 info2)
240{
241	host->status_mask = USDHI6_SD_INFO1_IRQ & ~info1;
242	host->status2_mask = USDHI6_SD_INFO2_IRQ & ~info2;
243	usdhi6_write(host, USDHI6_SD_INFO1_MASK, host->status_mask);
244	usdhi6_write(host, USDHI6_SD_INFO2_MASK, host->status2_mask);
245}
246
247static void usdhi6_wait_for_resp(struct usdhi6_host *host)
248{
249	usdhi6_irq_enable(host, USDHI6_SD_INFO1_RSP_END |
250			  USDHI6_SD_INFO1_ACCESS_END | USDHI6_SD_INFO1_CARD_CD,
251			  USDHI6_SD_INFO2_ERR);
252}
253
254static void usdhi6_wait_for_brwe(struct usdhi6_host *host, bool read)
255{
256	usdhi6_irq_enable(host, USDHI6_SD_INFO1_ACCESS_END |
257			  USDHI6_SD_INFO1_CARD_CD, USDHI6_SD_INFO2_ERR |
258			  (read ? USDHI6_SD_INFO2_BRE : USDHI6_SD_INFO2_BWE));
259}
260
261static void usdhi6_only_cd(struct usdhi6_host *host)
262{
263	/* Mask all except card hotplug */
264	usdhi6_irq_enable(host, USDHI6_SD_INFO1_CARD_CD, 0);
265}
266
267static void usdhi6_mask_all(struct usdhi6_host *host)
268{
269	usdhi6_irq_enable(host, 0, 0);
270}
271
272static int usdhi6_error_code(struct usdhi6_host *host)
273{
274	u32 err;
275
276	usdhi6_write(host, USDHI6_SD_STOP, USDHI6_SD_STOP_STP);
277
278	if (host->io_error &
279	    (USDHI6_SD_INFO2_RSP_TOUT | USDHI6_SD_INFO2_TOUT)) {
280		u32 rsp54 = usdhi6_read(host, USDHI6_SD_RSP54);
281		int opc = host->mrq ? host->mrq->cmd->opcode : -1;
282
283		err = usdhi6_read(host, USDHI6_SD_ERR_STS2);
284		/* Response timeout is often normal, don't spam the log */
285		if (host->wait == USDHI6_WAIT_FOR_CMD)
286			dev_dbg(mmc_dev(host->mmc),
287				"T-out sts 0x%x, resp 0x%x, state %u, CMD%d\n",
288				err, rsp54, host->wait, opc);
289		else
290			dev_warn(mmc_dev(host->mmc),
291				 "T-out sts 0x%x, resp 0x%x, state %u, CMD%d\n",
292				 err, rsp54, host->wait, opc);
293		return -ETIMEDOUT;
294	}
295
296	err = usdhi6_read(host, USDHI6_SD_ERR_STS1);
297	if (err != USDHI6_SD_ERR_STS1_CRC_NO_ERROR)
298		dev_warn(mmc_dev(host->mmc), "Err sts 0x%x, state %u, CMD%d\n",
299			 err, host->wait, host->mrq ? host->mrq->cmd->opcode : -1);
300	if (host->io_error & USDHI6_SD_INFO2_ILA)
301		return -EILSEQ;
302
303	return -EIO;
304}
305
306/*			Scatter-Gather management			*/
307
308/*
309 * In PIO mode we have to map each page separately, using kmap(). That way
310 * adjacent pages are mapped to non-adjacent virtual addresses. That's why we
311 * have to use a bounce buffer for blocks, crossing page boundaries. Such blocks
312 * have been observed with an SDIO WiFi card (b43 driver).
313 */
314static void usdhi6_blk_bounce(struct usdhi6_host *host,
315			      struct scatterlist *sg)
316{
317	struct mmc_data *data = host->mrq->data;
318	size_t blk_head = host->head_len;
319
320	dev_dbg(mmc_dev(host->mmc), "%s(): CMD%u of %u SG: %ux%u @ 0x%x\n",
321		__func__, host->mrq->cmd->opcode, data->sg_len,
322		data->blksz, data->blocks, sg->offset);
323
324	host->head_pg.page	= host->pg.page;
325	host->head_pg.mapped	= host->pg.mapped;
326	host->pg.page		= nth_page(host->pg.page, 1);
327	host->pg.mapped		= kmap(host->pg.page);
328
329	host->blk_page = host->bounce_buf;
330	host->offset = 0;
331
332	if (data->flags & MMC_DATA_READ)
333		return;
334
335	memcpy(host->bounce_buf, host->head_pg.mapped + PAGE_SIZE - blk_head,
336	       blk_head);
337	memcpy(host->bounce_buf + blk_head, host->pg.mapped,
338	       data->blksz - blk_head);
339}
340
341/* Only called for multiple block IO */
342static void usdhi6_sg_prep(struct usdhi6_host *host)
343{
344	struct mmc_request *mrq = host->mrq;
345	struct mmc_data *data = mrq->data;
346
347	usdhi6_write(host, USDHI6_SD_SECCNT, data->blocks);
348
349	host->sg = data->sg;
350	/* TODO: if we always map, this is redundant */
351	host->offset = host->sg->offset;
352}
353
354/* Map the first page in an SG segment: common for multiple and single block IO */
355static void *usdhi6_sg_map(struct usdhi6_host *host)
356{
357	struct mmc_data *data = host->mrq->data;
358	struct scatterlist *sg = data->sg_len > 1 ? host->sg : data->sg;
359	size_t head = PAGE_SIZE - sg->offset;
360	size_t blk_head = head % data->blksz;
361
362	WARN(host->pg.page, "%p not properly unmapped!\n", host->pg.page);
363	if (WARN(sg_dma_len(sg) % data->blksz,
364		 "SG size %u isn't a multiple of block size %u\n",
365		 sg_dma_len(sg), data->blksz))
366		return NULL;
367
368	host->pg.page = sg_page(sg);
369	host->pg.mapped = kmap(host->pg.page);
370	host->offset = sg->offset;
371
372	/*
373	 * Block size must be a power of 2 for multi-block transfers,
374	 * therefore blk_head is equal for all pages in this SG
375	 */
376	host->head_len = blk_head;
377
378	if (head < data->blksz)
379		/*
380		 * The first block in the SG crosses a page boundary.
381		 * Max blksz = 512, so blocks can only span 2 pages
382		 */
383		usdhi6_blk_bounce(host, sg);
384	else
385		host->blk_page = host->pg.mapped;
386
387	dev_dbg(mmc_dev(host->mmc), "Mapped %p (%lx) at %p + %u for CMD%u @ 0x%p\n",
388		host->pg.page, page_to_pfn(host->pg.page), host->pg.mapped,
389		sg->offset, host->mrq->cmd->opcode, host->mrq);
390
391	return host->blk_page + host->offset;
392}
393
394/* Unmap the current page: common for multiple and single block IO */
395static void usdhi6_sg_unmap(struct usdhi6_host *host, bool force)
396{
397	struct mmc_data *data = host->mrq->data;
398	struct page *page = host->head_pg.page;
399
400	if (page) {
401		/* Previous block was cross-page boundary */
402		struct scatterlist *sg = data->sg_len > 1 ?
403			host->sg : data->sg;
404		size_t blk_head = host->head_len;
405
406		if (!data->error && data->flags & MMC_DATA_READ) {
407			memcpy(host->head_pg.mapped + PAGE_SIZE - blk_head,
408			       host->bounce_buf, blk_head);
409			memcpy(host->pg.mapped, host->bounce_buf + blk_head,
410			       data->blksz - blk_head);
411		}
412
413		flush_dcache_page(page);
414		kunmap(page);
415
416		host->head_pg.page = NULL;
417
418		if (!force && sg_dma_len(sg) + sg->offset >
419		    (host->page_idx << PAGE_SHIFT) + data->blksz - blk_head)
420			/* More blocks in this SG, don't unmap the next page */
421			return;
422	}
423
424	page = host->pg.page;
425	if (!page)
426		return;
427
428	flush_dcache_page(page);
429	kunmap(page);
430
431	host->pg.page = NULL;
432}
433
434/* Called from MMC_WRITE_MULTIPLE_BLOCK or MMC_READ_MULTIPLE_BLOCK */
435static void usdhi6_sg_advance(struct usdhi6_host *host)
436{
437	struct mmc_data *data = host->mrq->data;
438	size_t done, total;
439
440	/* New offset: set at the end of the previous block */
441	if (host->head_pg.page) {
442		/* Finished a cross-page block, jump to the new page */
443		host->page_idx++;
444		host->offset = data->blksz - host->head_len;
445		host->blk_page = host->pg.mapped;
446		usdhi6_sg_unmap(host, false);
447	} else {
448		host->offset += data->blksz;
449		/* The completed block didn't cross a page boundary */
450		if (host->offset == PAGE_SIZE) {
451			/* If required, we'll map the page below */
452			host->offset = 0;
453			host->page_idx++;
454		}
455	}
456
457	/*
458	 * Now host->blk_page + host->offset point at the end of our last block
459	 * and host->page_idx is the index of the page, in which our new block
460	 * is located, if any
461	 */
462
463	done = (host->page_idx << PAGE_SHIFT) + host->offset;
464	total = host->sg->offset + sg_dma_len(host->sg);
465
466	dev_dbg(mmc_dev(host->mmc), "%s(): %zu of %zu @ %zu\n", __func__,
467		done, total, host->offset);
468
469	if (done < total && host->offset) {
470		/* More blocks in this page */
471		if (host->offset + data->blksz > PAGE_SIZE)
472			/* We approached at a block, that spans 2 pages */
473			usdhi6_blk_bounce(host, host->sg);
474
475		return;
476	}
477
478	/* Finished current page or an SG segment */
479	usdhi6_sg_unmap(host, false);
480
481	if (done == total) {
482		/*
483		 * End of an SG segment or the complete SG: jump to the next
484		 * segment, we'll map it later in usdhi6_blk_read() or
485		 * usdhi6_blk_write()
486		 */
487		struct scatterlist *next = sg_next(host->sg);
488
489		host->page_idx = 0;
490
491		if (!next)
492			host->wait = USDHI6_WAIT_FOR_DATA_END;
493		host->sg = next;
494
495		if (WARN(next && sg_dma_len(next) % data->blksz,
496			 "SG size %u isn't a multiple of block size %u\n",
497			 sg_dma_len(next), data->blksz))
498			data->error = -EINVAL;
499
500		return;
501	}
502
503	/* We cannot get here after crossing a page border */
504
505	/* Next page in the same SG */
506	host->pg.page = nth_page(sg_page(host->sg), host->page_idx);
507	host->pg.mapped = kmap(host->pg.page);
508	host->blk_page = host->pg.mapped;
509
510	dev_dbg(mmc_dev(host->mmc), "Mapped %p (%lx) at %p for CMD%u @ 0x%p\n",
511		host->pg.page, page_to_pfn(host->pg.page), host->pg.mapped,
512		host->mrq->cmd->opcode, host->mrq);
513}
514
515/*			DMA handling					*/
516
517static void usdhi6_dma_release(struct usdhi6_host *host)
518{
519	host->dma_active = false;
520	if (host->chan_tx) {
521		struct dma_chan *chan = host->chan_tx;
522		host->chan_tx = NULL;
523		dma_release_channel(chan);
524	}
525	if (host->chan_rx) {
526		struct dma_chan *chan = host->chan_rx;
527		host->chan_rx = NULL;
528		dma_release_channel(chan);
529	}
530}
531
532static void usdhi6_dma_stop_unmap(struct usdhi6_host *host)
533{
534	struct mmc_data *data = host->mrq->data;
535
536	if (!host->dma_active)
537		return;
538
539	usdhi6_write(host, USDHI6_CC_EXT_MODE, 0);
540	host->dma_active = false;
541
542	if (data->flags & MMC_DATA_READ)
543		dma_unmap_sg(host->chan_rx->device->dev, data->sg,
544			     data->sg_len, DMA_FROM_DEVICE);
545	else
546		dma_unmap_sg(host->chan_tx->device->dev, data->sg,
547			     data->sg_len, DMA_TO_DEVICE);
548}
549
550static void usdhi6_dma_complete(void *arg)
551{
552	struct usdhi6_host *host = arg;
553	struct mmc_request *mrq = host->mrq;
554
555	if (WARN(!mrq || !mrq->data, "%s: NULL data in DMA completion for %p!\n",
556		 dev_name(mmc_dev(host->mmc)), mrq))
557		return;
558
559	dev_dbg(mmc_dev(host->mmc), "%s(): CMD%u DMA completed\n", __func__,
560		mrq->cmd->opcode);
561
562	usdhi6_dma_stop_unmap(host);
563	usdhi6_wait_for_brwe(host, mrq->data->flags & MMC_DATA_READ);
564}
565
566static int usdhi6_dma_setup(struct usdhi6_host *host, struct dma_chan *chan,
567			    enum dma_transfer_direction dir)
568{
569	struct mmc_data *data = host->mrq->data;
570	struct scatterlist *sg = data->sg;
571	struct dma_async_tx_descriptor *desc = NULL;
572	dma_cookie_t cookie = -EINVAL;
573	enum dma_data_direction data_dir;
574	int ret;
575
576	switch (dir) {
577	case DMA_MEM_TO_DEV:
578		data_dir = DMA_TO_DEVICE;
579		break;
580	case DMA_DEV_TO_MEM:
581		data_dir = DMA_FROM_DEVICE;
582		break;
583	default:
584		return -EINVAL;
585	}
586
587	ret = dma_map_sg(chan->device->dev, sg, data->sg_len, data_dir);
588	if (ret > 0) {
589		host->dma_active = true;
590		desc = dmaengine_prep_slave_sg(chan, sg, ret, dir,
591					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
592	}
593
594	if (desc) {
595		desc->callback = usdhi6_dma_complete;
596		desc->callback_param = host;
597		cookie = dmaengine_submit(desc);
598	}
599
600	dev_dbg(mmc_dev(host->mmc), "%s(): mapped %d -> %d, cookie %d @ %p\n",
601		__func__, data->sg_len, ret, cookie, desc);
602
603	if (cookie < 0) {
604		/* DMA failed, fall back to PIO */
605		if (ret >= 0)
606			ret = cookie;
607		usdhi6_dma_release(host);
608		dev_warn(mmc_dev(host->mmc),
609			 "DMA failed: %d, falling back to PIO\n", ret);
610	}
611
612	return cookie;
613}
614
615static int usdhi6_dma_start(struct usdhi6_host *host)
616{
617	if (!host->chan_rx || !host->chan_tx)
618		return -ENODEV;
619
620	if (host->mrq->data->flags & MMC_DATA_READ)
621		return usdhi6_dma_setup(host, host->chan_rx, DMA_DEV_TO_MEM);
622
623	return usdhi6_dma_setup(host, host->chan_tx, DMA_MEM_TO_DEV);
624}
625
626static void usdhi6_dma_kill(struct usdhi6_host *host)
627{
628	struct mmc_data *data = host->mrq->data;
629
630	dev_dbg(mmc_dev(host->mmc), "%s(): SG of %u: %ux%u\n",
631		__func__, data->sg_len, data->blocks, data->blksz);
632	/* Abort DMA */
633	if (data->flags & MMC_DATA_READ)
634		dmaengine_terminate_sync(host->chan_rx);
635	else
636		dmaengine_terminate_sync(host->chan_tx);
637}
638
639static void usdhi6_dma_check_error(struct usdhi6_host *host)
640{
641	struct mmc_data *data = host->mrq->data;
642
643	dev_dbg(mmc_dev(host->mmc), "%s(): IO error %d, status 0x%x\n",
644		__func__, host->io_error, usdhi6_read(host, USDHI6_SD_INFO1));
645
646	if (host->io_error) {
647		data->error = usdhi6_error_code(host);
648		data->bytes_xfered = 0;
649		usdhi6_dma_kill(host);
650		usdhi6_dma_release(host);
651		dev_warn(mmc_dev(host->mmc),
652			 "DMA failed: %d, falling back to PIO\n", data->error);
653		return;
654	}
655
656	/*
657	 * The datasheet tells us to check a response from the card, whereas
658	 * responses only come after the command phase, not after the data
659	 * phase. Let's check anyway.
660	 */
661	if (host->irq_status & USDHI6_SD_INFO1_RSP_END)
662		dev_warn(mmc_dev(host->mmc), "Unexpected response received!\n");
663}
664
665static void usdhi6_dma_kick(struct usdhi6_host *host)
666{
667	if (host->mrq->data->flags & MMC_DATA_READ)
668		dma_async_issue_pending(host->chan_rx);
669	else
670		dma_async_issue_pending(host->chan_tx);
671}
672
673static void usdhi6_dma_request(struct usdhi6_host *host, phys_addr_t start)
674{
675	struct dma_slave_config cfg = {
676		.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
677		.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
678	};
679	int ret;
680
681	host->chan_tx = dma_request_chan(mmc_dev(host->mmc), "tx");
682	dev_dbg(mmc_dev(host->mmc), "%s: TX: got channel %p\n", __func__,
683		host->chan_tx);
684
685	if (IS_ERR(host->chan_tx)) {
686		host->chan_tx = NULL;
687		return;
688	}
689
690	cfg.direction = DMA_MEM_TO_DEV;
691	cfg.dst_addr = start + USDHI6_SD_BUF0;
692	cfg.dst_maxburst = 128;	/* 128 words * 4 bytes = 512 bytes */
693	cfg.src_addr = 0;
694	ret = dmaengine_slave_config(host->chan_tx, &cfg);
695	if (ret < 0)
696		goto e_release_tx;
697
698	host->chan_rx = dma_request_chan(mmc_dev(host->mmc), "rx");
699	dev_dbg(mmc_dev(host->mmc), "%s: RX: got channel %p\n", __func__,
700		host->chan_rx);
701
702	if (IS_ERR(host->chan_rx)) {
703		host->chan_rx = NULL;
704		goto e_release_tx;
705	}
706
707	cfg.direction = DMA_DEV_TO_MEM;
708	cfg.src_addr = cfg.dst_addr;
709	cfg.src_maxburst = 128;	/* 128 words * 4 bytes = 512 bytes */
710	cfg.dst_addr = 0;
711	ret = dmaengine_slave_config(host->chan_rx, &cfg);
712	if (ret < 0)
713		goto e_release_rx;
714
715	return;
716
717e_release_rx:
718	dma_release_channel(host->chan_rx);
719	host->chan_rx = NULL;
720e_release_tx:
721	dma_release_channel(host->chan_tx);
722	host->chan_tx = NULL;
723}
724
725/*			API helpers					*/
726
727static void usdhi6_clk_set(struct usdhi6_host *host, struct mmc_ios *ios)
728{
729	unsigned long rate = ios->clock;
730	u32 val;
731	unsigned int i;
732
733	for (i = 1000; i; i--) {
734		if (usdhi6_read(host, USDHI6_SD_INFO2) & USDHI6_SD_INFO2_SCLKDIVEN)
735			break;
736		usleep_range(10, 100);
737	}
738
739	if (!i) {
740		dev_err(mmc_dev(host->mmc), "SD bus busy, clock set aborted\n");
741		return;
742	}
743
744	val = usdhi6_read(host, USDHI6_SD_CLK_CTRL) & ~USDHI6_SD_CLK_CTRL_DIV_MASK;
745
746	if (rate) {
747		unsigned long new_rate;
748
749		if (host->imclk <= rate) {
750			if (ios->timing != MMC_TIMING_UHS_DDR50) {
751				/* Cannot have 1-to-1 clock in DDR mode */
752				new_rate = host->imclk;
753				val |= 0xff;
754			} else {
755				new_rate = host->imclk / 2;
756			}
757		} else {
758			unsigned long div =
759				roundup_pow_of_two(DIV_ROUND_UP(host->imclk, rate));
760			val |= div >> 2;
761			new_rate = host->imclk / div;
762		}
763
764		if (host->rate == new_rate)
765			return;
766
767		host->rate = new_rate;
768
769		dev_dbg(mmc_dev(host->mmc), "target %lu, div %u, set %lu\n",
770			rate, (val & 0xff) << 2, new_rate);
771	}
772
773	/*
774	 * if old or new rate is equal to input rate, have to switch the clock
775	 * off before changing and on after
776	 */
777	if (host->imclk == rate || host->imclk == host->rate || !rate)
778		usdhi6_write(host, USDHI6_SD_CLK_CTRL,
779			     val & ~USDHI6_SD_CLK_CTRL_SCLKEN);
780
781	if (!rate) {
782		host->rate = 0;
783		return;
784	}
785
786	usdhi6_write(host, USDHI6_SD_CLK_CTRL, val);
787
788	if (host->imclk == rate || host->imclk == host->rate ||
789	    !(val & USDHI6_SD_CLK_CTRL_SCLKEN))
790		usdhi6_write(host, USDHI6_SD_CLK_CTRL,
791			     val | USDHI6_SD_CLK_CTRL_SCLKEN);
792}
793
794static void usdhi6_set_power(struct usdhi6_host *host, struct mmc_ios *ios)
795{
796	struct mmc_host *mmc = host->mmc;
797
798	if (!IS_ERR(mmc->supply.vmmc))
799		/* Errors ignored... */
800		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc,
801				      ios->power_mode ? ios->vdd : 0);
802}
803
804static int usdhi6_reset(struct usdhi6_host *host)
805{
806	int i;
807
808	usdhi6_write(host, USDHI6_SOFT_RST, USDHI6_SOFT_RST_RESERVED);
809	cpu_relax();
810	usdhi6_write(host, USDHI6_SOFT_RST, USDHI6_SOFT_RST_RESERVED | USDHI6_SOFT_RST_RESET);
811	for (i = 1000; i; i--)
812		if (usdhi6_read(host, USDHI6_SOFT_RST) & USDHI6_SOFT_RST_RESET)
813			break;
814
815	return i ? 0 : -ETIMEDOUT;
816}
817
818static void usdhi6_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
819{
820	struct usdhi6_host *host = mmc_priv(mmc);
821	u32 option, mode;
822	int ret;
823
824	dev_dbg(mmc_dev(mmc), "%uHz, OCR: %u, power %u, bus-width %u, timing %u\n",
825		ios->clock, ios->vdd, ios->power_mode, ios->bus_width, ios->timing);
826
827	switch (ios->power_mode) {
828	case MMC_POWER_OFF:
829		usdhi6_set_power(host, ios);
830		usdhi6_only_cd(host);
831		break;
832	case MMC_POWER_UP:
833		/*
834		 * We only also touch USDHI6_SD_OPTION from .request(), which
835		 * cannot race with MMC_POWER_UP
836		 */
837		ret = usdhi6_reset(host);
838		if (ret < 0) {
839			dev_err(mmc_dev(mmc), "Cannot reset the interface!\n");
840		} else {
841			usdhi6_set_power(host, ios);
842			usdhi6_only_cd(host);
843		}
844		break;
845	case MMC_POWER_ON:
846		option = usdhi6_read(host, USDHI6_SD_OPTION);
847		/*
848		 * The eMMC standard only allows 4 or 8 bits in the DDR mode,
849		 * the same probably holds for SD cards. We check here anyway,
850		 * since the datasheet explicitly requires 4 bits for DDR.
851		 */
852		if (ios->bus_width == MMC_BUS_WIDTH_1) {
853			if (ios->timing == MMC_TIMING_UHS_DDR50)
854				dev_err(mmc_dev(mmc),
855					"4 bits are required for DDR\n");
856			option |= USDHI6_SD_OPTION_WIDTH_1;
857			mode = 0;
858		} else {
859			option &= ~USDHI6_SD_OPTION_WIDTH_1;
860			mode = ios->timing == MMC_TIMING_UHS_DDR50;
861		}
862		usdhi6_write(host, USDHI6_SD_OPTION, option);
863		usdhi6_write(host, USDHI6_SDIF_MODE, mode);
864		break;
865	}
866
867	if (host->rate != ios->clock)
868		usdhi6_clk_set(host, ios);
869}
870
871/* This is data timeout. Response timeout is fixed to 640 clock cycles */
872static void usdhi6_timeout_set(struct usdhi6_host *host)
873{
874	struct mmc_request *mrq = host->mrq;
875	u32 val;
876	unsigned long ticks;
877
878	if (!mrq->data)
879		ticks = host->rate / 1000 * mrq->cmd->busy_timeout;
880	else
881		ticks = host->rate / 1000000 * (mrq->data->timeout_ns / 1000) +
882			mrq->data->timeout_clks;
883
884	if (!ticks || ticks > 1 << 27)
885		/* Max timeout */
886		val = 14;
887	else if (ticks < 1 << 13)
888		/* Min timeout */
889		val = 0;
890	else
891		val = order_base_2(ticks) - 13;
892
893	dev_dbg(mmc_dev(host->mmc), "Set %s timeout %lu ticks @ %lu Hz\n",
894		mrq->data ? "data" : "cmd", ticks, host->rate);
895
896	/* Timeout Counter mask: 0xf0 */
897	usdhi6_write(host, USDHI6_SD_OPTION, (val << USDHI6_SD_OPTION_TIMEOUT_SHIFT) |
898		     (usdhi6_read(host, USDHI6_SD_OPTION) & ~USDHI6_SD_OPTION_TIMEOUT_MASK));
899}
900
901static void usdhi6_request_done(struct usdhi6_host *host)
902{
903	struct mmc_request *mrq = host->mrq;
904	struct mmc_data *data = mrq->data;
905
906	if (WARN(host->pg.page || host->head_pg.page,
907		 "Page %p or %p not unmapped: wait %u, CMD%d(%c) @ +0x%zx %ux%u in SG%u!\n",
908		 host->pg.page, host->head_pg.page, host->wait, mrq->cmd->opcode,
909		 data ? (data->flags & MMC_DATA_READ ? 'R' : 'W') : '-',
910		 data ? host->offset : 0, data ? data->blocks : 0,
911		 data ? data->blksz : 0, data ? data->sg_len : 0))
912		usdhi6_sg_unmap(host, true);
913
914	if (mrq->cmd->error ||
915	    (data && data->error) ||
916	    (mrq->stop && mrq->stop->error))
917		dev_dbg(mmc_dev(host->mmc), "%s(CMD%d: %ux%u): err %d %d %d\n",
918			__func__, mrq->cmd->opcode, data ? data->blocks : 0,
919			data ? data->blksz : 0,
920			mrq->cmd->error,
921			data ? data->error : 1,
922			mrq->stop ? mrq->stop->error : 1);
923
924	/* Disable DMA */
925	usdhi6_write(host, USDHI6_CC_EXT_MODE, 0);
926	host->wait = USDHI6_WAIT_FOR_REQUEST;
927	host->mrq = NULL;
928
929	mmc_request_done(host->mmc, mrq);
930}
931
932static int usdhi6_cmd_flags(struct usdhi6_host *host)
933{
934	struct mmc_request *mrq = host->mrq;
935	struct mmc_command *cmd = mrq->cmd;
936	u16 opc = cmd->opcode;
937
938	if (host->app_cmd) {
939		host->app_cmd = false;
940		opc |= USDHI6_SD_CMD_APP;
941	}
942
943	if (mrq->data) {
944		opc |= USDHI6_SD_CMD_DATA;
945
946		if (mrq->data->flags & MMC_DATA_READ)
947			opc |= USDHI6_SD_CMD_READ;
948
949		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
950		    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
951		    (cmd->opcode == SD_IO_RW_EXTENDED &&
952		     mrq->data->blocks > 1)) {
953			opc |= USDHI6_SD_CMD_MULTI;
954			if (!mrq->stop)
955				opc |= USDHI6_SD_CMD_CMD12_AUTO_OFF;
956		}
957
958		switch (mmc_resp_type(cmd)) {
959		case MMC_RSP_NONE:
960			opc |= USDHI6_SD_CMD_MODE_RSP_NONE;
961			break;
962		case MMC_RSP_R1:
963			opc |= USDHI6_SD_CMD_MODE_RSP_R1;
964			break;
965		case MMC_RSP_R1B:
966			opc |= USDHI6_SD_CMD_MODE_RSP_R1B;
967			break;
968		case MMC_RSP_R2:
969			opc |= USDHI6_SD_CMD_MODE_RSP_R2;
970			break;
971		case MMC_RSP_R3:
972			opc |= USDHI6_SD_CMD_MODE_RSP_R3;
973			break;
974		default:
975			dev_warn(mmc_dev(host->mmc),
976				 "Unknown response type %d\n",
977				 mmc_resp_type(cmd));
978			return -EINVAL;
979		}
980	}
981
982	return opc;
983}
984
985static int usdhi6_rq_start(struct usdhi6_host *host)
986{
987	struct mmc_request *mrq = host->mrq;
988	struct mmc_command *cmd = mrq->cmd;
989	struct mmc_data *data = mrq->data;
990	int opc = usdhi6_cmd_flags(host);
991	int i;
992
993	if (opc < 0)
994		return opc;
995
996	for (i = 1000; i; i--) {
997		if (!(usdhi6_read(host, USDHI6_SD_INFO2) & USDHI6_SD_INFO2_CBSY))
998			break;
999		usleep_range(10, 100);
1000	}
1001
1002	if (!i) {
1003		dev_dbg(mmc_dev(host->mmc), "Command active, request aborted\n");
1004		return -EAGAIN;
1005	}
1006
1007	if (data) {
1008		bool use_dma;
1009		int ret = 0;
1010
1011		host->page_idx = 0;
1012
1013		if (cmd->opcode == SD_IO_RW_EXTENDED && data->blocks > 1) {
1014			switch (data->blksz) {
1015			case 512:
1016				break;
1017			case 32:
1018			case 64:
1019			case 128:
1020			case 256:
1021				if (mrq->stop)
1022					ret = -EINVAL;
1023				break;
1024			default:
1025				ret = -EINVAL;
1026			}
1027		} else if ((cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1028			    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK) &&
1029			   data->blksz != 512) {
1030			ret = -EINVAL;
1031		}
1032
1033		if (ret < 0) {
1034			dev_warn(mmc_dev(host->mmc), "%s(): %u blocks of %u bytes\n",
1035				 __func__, data->blocks, data->blksz);
1036			return -EINVAL;
1037		}
1038
1039		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1040		    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
1041		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1042		     data->blocks > 1))
1043			usdhi6_sg_prep(host);
1044
1045		usdhi6_write(host, USDHI6_SD_SIZE, data->blksz);
1046
1047		if ((data->blksz >= USDHI6_MIN_DMA ||
1048		     data->blocks > 1) &&
1049		    (data->blksz % 4 ||
1050		     data->sg->offset % 4))
1051			dev_dbg(mmc_dev(host->mmc),
1052				"Bad SG of %u: %ux%u @ %u\n", data->sg_len,
1053				data->blksz, data->blocks, data->sg->offset);
1054
1055		/* Enable DMA for USDHI6_MIN_DMA bytes or more */
1056		use_dma = data->blksz >= USDHI6_MIN_DMA &&
1057			!(data->blksz % 4) &&
1058			usdhi6_dma_start(host) >= DMA_MIN_COOKIE;
1059
1060		if (use_dma)
1061			usdhi6_write(host, USDHI6_CC_EXT_MODE, USDHI6_CC_EXT_MODE_SDRW);
1062
1063		dev_dbg(mmc_dev(host->mmc),
1064			"%s(): request opcode %u, %u blocks of %u bytes in %u segments, %s %s @+0x%x%s\n",
1065			__func__, cmd->opcode, data->blocks, data->blksz,
1066			data->sg_len, use_dma ? "DMA" : "PIO",
1067			data->flags & MMC_DATA_READ ? "read" : "write",
1068			data->sg->offset, mrq->stop ? " + stop" : "");
1069	} else {
1070		dev_dbg(mmc_dev(host->mmc), "%s(): request opcode %u\n",
1071			__func__, cmd->opcode);
1072	}
1073
1074	/* We have to get a command completion interrupt with DMA too */
1075	usdhi6_wait_for_resp(host);
1076
1077	host->wait = USDHI6_WAIT_FOR_CMD;
1078	schedule_delayed_work(&host->timeout_work, host->timeout);
1079
1080	/* SEC bit is required to enable block counting by the core */
1081	usdhi6_write(host, USDHI6_SD_STOP,
1082		     data && data->blocks > 1 ? USDHI6_SD_STOP_SEC : 0);
1083	usdhi6_write(host, USDHI6_SD_ARG, cmd->arg);
1084
1085	/* Kick command execution */
1086	usdhi6_write(host, USDHI6_SD_CMD, opc);
1087
1088	return 0;
1089}
1090
1091static void usdhi6_request(struct mmc_host *mmc, struct mmc_request *mrq)
1092{
1093	struct usdhi6_host *host = mmc_priv(mmc);
1094	int ret;
1095
1096	cancel_delayed_work_sync(&host->timeout_work);
1097
1098	host->mrq = mrq;
1099	host->sg = NULL;
1100
1101	usdhi6_timeout_set(host);
1102	ret = usdhi6_rq_start(host);
1103	if (ret < 0) {
1104		mrq->cmd->error = ret;
1105		usdhi6_request_done(host);
1106	}
1107}
1108
1109static int usdhi6_get_cd(struct mmc_host *mmc)
1110{
1111	struct usdhi6_host *host = mmc_priv(mmc);
1112	/* Read is atomic, no need to lock */
1113	u32 status = usdhi6_read(host, USDHI6_SD_INFO1) & USDHI6_SD_INFO1_CD;
1114
1115/*
1116 *	level	status.CD	CD_ACTIVE_HIGH	card present
1117 *	1	0		0		0
1118 *	1	0		1		1
1119 *	0	1		0		1
1120 *	0	1		1		0
1121 */
1122	return !status ^ !(mmc->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
1123}
1124
1125static int usdhi6_get_ro(struct mmc_host *mmc)
1126{
1127	struct usdhi6_host *host = mmc_priv(mmc);
1128	/* No locking as above */
1129	u32 status = usdhi6_read(host, USDHI6_SD_INFO1) & USDHI6_SD_INFO1_WP;
1130
1131/*
1132 *	level	status.WP	RO_ACTIVE_HIGH	card read-only
1133 *	1	0		0		0
1134 *	1	0		1		1
1135 *	0	1		0		1
1136 *	0	1		1		0
1137 */
1138	return !status ^ !(mmc->caps2 & MMC_CAP2_RO_ACTIVE_HIGH);
1139}
1140
1141static void usdhi6_enable_sdio_irq(struct mmc_host *mmc, int enable)
1142{
1143	struct usdhi6_host *host = mmc_priv(mmc);
1144
1145	dev_dbg(mmc_dev(mmc), "%s(): %sable\n", __func__, enable ? "en" : "dis");
1146
1147	if (enable) {
1148		host->sdio_mask = USDHI6_SDIO_INFO1_IRQ & ~USDHI6_SDIO_INFO1_IOIRQ;
1149		usdhi6_write(host, USDHI6_SDIO_INFO1_MASK, host->sdio_mask);
1150		usdhi6_write(host, USDHI6_SDIO_MODE, 1);
1151	} else {
1152		usdhi6_write(host, USDHI6_SDIO_MODE, 0);
1153		usdhi6_write(host, USDHI6_SDIO_INFO1_MASK, USDHI6_SDIO_INFO1_IRQ);
1154		host->sdio_mask = USDHI6_SDIO_INFO1_IRQ;
1155	}
1156}
1157
1158static int usdhi6_set_pinstates(struct usdhi6_host *host, int voltage)
1159{
1160	if (IS_ERR(host->pins_uhs))
1161		return 0;
1162
1163	switch (voltage) {
1164	case MMC_SIGNAL_VOLTAGE_180:
1165	case MMC_SIGNAL_VOLTAGE_120:
1166		return pinctrl_select_state(host->pinctrl,
1167					    host->pins_uhs);
1168
1169	default:
1170		return pinctrl_select_default_state(mmc_dev(host->mmc));
1171	}
1172}
1173
1174static int usdhi6_sig_volt_switch(struct mmc_host *mmc, struct mmc_ios *ios)
1175{
1176	int ret;
1177
1178	ret = mmc_regulator_set_vqmmc(mmc, ios);
1179	if (ret < 0)
1180		return ret;
1181
1182	ret = usdhi6_set_pinstates(mmc_priv(mmc), ios->signal_voltage);
1183	if (ret)
1184		dev_warn_once(mmc_dev(mmc),
1185			      "Failed to set pinstate err=%d\n", ret);
1186	return ret;
1187}
1188
1189static int usdhi6_card_busy(struct mmc_host *mmc)
1190{
1191	struct usdhi6_host *host = mmc_priv(mmc);
1192	u32 tmp = usdhi6_read(host, USDHI6_SD_INFO2);
1193
1194	/* Card is busy if it is pulling dat[0] low */
1195	return !(tmp & USDHI6_SD_INFO2_SDDAT0);
1196}
1197
1198static const struct mmc_host_ops usdhi6_ops = {
1199	.request	= usdhi6_request,
1200	.set_ios	= usdhi6_set_ios,
1201	.get_cd		= usdhi6_get_cd,
1202	.get_ro		= usdhi6_get_ro,
1203	.enable_sdio_irq = usdhi6_enable_sdio_irq,
1204	.start_signal_voltage_switch = usdhi6_sig_volt_switch,
1205	.card_busy = usdhi6_card_busy,
1206};
1207
1208/*			State machine handlers				*/
1209
1210static void usdhi6_resp_cmd12(struct usdhi6_host *host)
1211{
1212	struct mmc_command *cmd = host->mrq->stop;
1213	cmd->resp[0] = usdhi6_read(host, USDHI6_SD_RSP10);
1214}
1215
1216static void usdhi6_resp_read(struct usdhi6_host *host)
1217{
1218	struct mmc_command *cmd = host->mrq->cmd;
1219	u32 *rsp = cmd->resp, tmp = 0;
1220	int i;
1221
1222/*
1223 * RSP10	39-8
1224 * RSP32	71-40
1225 * RSP54	103-72
1226 * RSP76	127-104
1227 * R2-type response:
1228 * resp[0]	= r[127..96]
1229 * resp[1]	= r[95..64]
1230 * resp[2]	= r[63..32]
1231 * resp[3]	= r[31..0]
1232 * Other responses:
1233 * resp[0]	= r[39..8]
1234 */
1235
1236	if (mmc_resp_type(cmd) == MMC_RSP_NONE)
1237		return;
1238
1239	if (!(host->irq_status & USDHI6_SD_INFO1_RSP_END)) {
1240		dev_err(mmc_dev(host->mmc),
1241			"CMD%d: response expected but is missing!\n", cmd->opcode);
1242		return;
1243	}
1244
1245	if (mmc_resp_type(cmd) & MMC_RSP_136)
1246		for (i = 0; i < 4; i++) {
1247			if (i)
1248				rsp[3 - i] = tmp >> 24;
1249			tmp = usdhi6_read(host, USDHI6_SD_RSP10 + i * 8);
1250			rsp[3 - i] |= tmp << 8;
1251		}
1252	else if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1253		 cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK)
1254		/* Read RSP54 to avoid conflict with auto CMD12 */
1255		rsp[0] = usdhi6_read(host, USDHI6_SD_RSP54);
1256	else
1257		rsp[0] = usdhi6_read(host, USDHI6_SD_RSP10);
1258
1259	dev_dbg(mmc_dev(host->mmc), "Response 0x%x\n", rsp[0]);
1260}
1261
1262static int usdhi6_blk_read(struct usdhi6_host *host)
1263{
1264	struct mmc_data *data = host->mrq->data;
1265	u32 *p;
1266	int i, rest;
1267
1268	if (host->io_error) {
1269		data->error = usdhi6_error_code(host);
1270		goto error;
1271	}
1272
1273	if (host->pg.page) {
1274		p = host->blk_page + host->offset;
1275	} else {
1276		p = usdhi6_sg_map(host);
1277		if (!p) {
1278			data->error = -ENOMEM;
1279			goto error;
1280		}
1281	}
1282
1283	for (i = 0; i < data->blksz / 4; i++, p++)
1284		*p = usdhi6_read(host, USDHI6_SD_BUF0);
1285
1286	rest = data->blksz % 4;
1287	for (i = 0; i < (rest + 1) / 2; i++) {
1288		u16 d = usdhi6_read16(host, USDHI6_SD_BUF0);
1289		((u8 *)p)[2 * i] = ((u8 *)&d)[0];
1290		if (rest > 1 && !i)
1291			((u8 *)p)[2 * i + 1] = ((u8 *)&d)[1];
1292	}
1293
1294	return 0;
1295
1296error:
1297	dev_dbg(mmc_dev(host->mmc), "%s(): %d\n", __func__, data->error);
1298	host->wait = USDHI6_WAIT_FOR_REQUEST;
1299	return data->error;
1300}
1301
1302static int usdhi6_blk_write(struct usdhi6_host *host)
1303{
1304	struct mmc_data *data = host->mrq->data;
1305	u32 *p;
1306	int i, rest;
1307
1308	if (host->io_error) {
1309		data->error = usdhi6_error_code(host);
1310		goto error;
1311	}
1312
1313	if (host->pg.page) {
1314		p = host->blk_page + host->offset;
1315	} else {
1316		p = usdhi6_sg_map(host);
1317		if (!p) {
1318			data->error = -ENOMEM;
1319			goto error;
1320		}
1321	}
1322
1323	for (i = 0; i < data->blksz / 4; i++, p++)
1324		usdhi6_write(host, USDHI6_SD_BUF0, *p);
1325
1326	rest = data->blksz % 4;
1327	for (i = 0; i < (rest + 1) / 2; i++) {
1328		u16 d;
1329		((u8 *)&d)[0] = ((u8 *)p)[2 * i];
1330		if (rest > 1 && !i)
1331			((u8 *)&d)[1] = ((u8 *)p)[2 * i + 1];
1332		else
1333			((u8 *)&d)[1] = 0;
1334		usdhi6_write16(host, USDHI6_SD_BUF0, d);
1335	}
1336
1337	return 0;
1338
1339error:
1340	dev_dbg(mmc_dev(host->mmc), "%s(): %d\n", __func__, data->error);
1341	host->wait = USDHI6_WAIT_FOR_REQUEST;
1342	return data->error;
1343}
1344
1345static int usdhi6_stop_cmd(struct usdhi6_host *host)
1346{
1347	struct mmc_request *mrq = host->mrq;
1348
1349	switch (mrq->cmd->opcode) {
1350	case MMC_READ_MULTIPLE_BLOCK:
1351	case MMC_WRITE_MULTIPLE_BLOCK:
1352		if (mrq->stop->opcode == MMC_STOP_TRANSMISSION) {
1353			host->wait = USDHI6_WAIT_FOR_STOP;
1354			return 0;
1355		}
1356		fallthrough;	/* Unsupported STOP command */
1357	default:
1358		dev_err(mmc_dev(host->mmc),
1359			"unsupported stop CMD%d for CMD%d\n",
1360			mrq->stop->opcode, mrq->cmd->opcode);
1361		mrq->stop->error = -EOPNOTSUPP;
1362	}
1363
1364	return -EOPNOTSUPP;
1365}
1366
1367static bool usdhi6_end_cmd(struct usdhi6_host *host)
1368{
1369	struct mmc_request *mrq = host->mrq;
1370	struct mmc_command *cmd = mrq->cmd;
1371
1372	if (host->io_error) {
1373		cmd->error = usdhi6_error_code(host);
1374		return false;
1375	}
1376
1377	usdhi6_resp_read(host);
1378
1379	if (!mrq->data)
1380		return false;
1381
1382	if (host->dma_active) {
1383		usdhi6_dma_kick(host);
1384		if (!mrq->stop)
1385			host->wait = USDHI6_WAIT_FOR_DMA;
1386		else if (usdhi6_stop_cmd(host) < 0)
1387			return false;
1388	} else if (mrq->data->flags & MMC_DATA_READ) {
1389		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1390		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1391		     mrq->data->blocks > 1))
1392			host->wait = USDHI6_WAIT_FOR_MREAD;
1393		else
1394			host->wait = USDHI6_WAIT_FOR_READ;
1395	} else {
1396		if (cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
1397		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1398		     mrq->data->blocks > 1))
1399			host->wait = USDHI6_WAIT_FOR_MWRITE;
1400		else
1401			host->wait = USDHI6_WAIT_FOR_WRITE;
1402	}
1403
1404	return true;
1405}
1406
1407static bool usdhi6_read_block(struct usdhi6_host *host)
1408{
1409	/* ACCESS_END IRQ is already unmasked */
1410	int ret = usdhi6_blk_read(host);
1411
1412	/*
1413	 * Have to force unmapping both pages: the single block could have been
1414	 * cross-page, in which case for single-block IO host->page_idx == 0.
1415	 * So, if we don't force, the second page won't be unmapped.
1416	 */
1417	usdhi6_sg_unmap(host, true);
1418
1419	if (ret < 0)
1420		return false;
1421
1422	host->wait = USDHI6_WAIT_FOR_DATA_END;
1423	return true;
1424}
1425
1426static bool usdhi6_mread_block(struct usdhi6_host *host)
1427{
1428	int ret = usdhi6_blk_read(host);
1429
1430	if (ret < 0)
1431		return false;
1432
1433	usdhi6_sg_advance(host);
1434
1435	return !host->mrq->data->error &&
1436		(host->wait != USDHI6_WAIT_FOR_DATA_END || !host->mrq->stop);
1437}
1438
1439static bool usdhi6_write_block(struct usdhi6_host *host)
1440{
1441	int ret = usdhi6_blk_write(host);
1442
1443	/* See comment in usdhi6_read_block() */
1444	usdhi6_sg_unmap(host, true);
1445
1446	if (ret < 0)
1447		return false;
1448
1449	host->wait = USDHI6_WAIT_FOR_DATA_END;
1450	return true;
1451}
1452
1453static bool usdhi6_mwrite_block(struct usdhi6_host *host)
1454{
1455	int ret = usdhi6_blk_write(host);
1456
1457	if (ret < 0)
1458		return false;
1459
1460	usdhi6_sg_advance(host);
1461
1462	return !host->mrq->data->error &&
1463		(host->wait != USDHI6_WAIT_FOR_DATA_END || !host->mrq->stop);
1464}
1465
1466/*			Interrupt & timeout handlers			*/
1467
1468static irqreturn_t usdhi6_sd_bh(int irq, void *dev_id)
1469{
1470	struct usdhi6_host *host = dev_id;
1471	struct mmc_request *mrq;
1472	struct mmc_command *cmd;
1473	struct mmc_data *data;
1474	bool io_wait = false;
1475
1476	cancel_delayed_work_sync(&host->timeout_work);
1477
1478	mrq = host->mrq;
1479	if (!mrq)
1480		return IRQ_HANDLED;
1481
1482	cmd = mrq->cmd;
1483	data = mrq->data;
1484
1485	switch (host->wait) {
1486	case USDHI6_WAIT_FOR_REQUEST:
1487		/* We're too late, the timeout has already kicked in */
1488		return IRQ_HANDLED;
1489	case USDHI6_WAIT_FOR_CMD:
1490		/* Wait for data? */
1491		io_wait = usdhi6_end_cmd(host);
1492		break;
1493	case USDHI6_WAIT_FOR_MREAD:
1494		/* Wait for more data? */
1495		io_wait = usdhi6_mread_block(host);
1496		break;
1497	case USDHI6_WAIT_FOR_READ:
1498		/* Wait for data end? */
1499		io_wait = usdhi6_read_block(host);
1500		break;
1501	case USDHI6_WAIT_FOR_MWRITE:
1502		/* Wait data to write? */
1503		io_wait = usdhi6_mwrite_block(host);
1504		break;
1505	case USDHI6_WAIT_FOR_WRITE:
1506		/* Wait for data end? */
1507		io_wait = usdhi6_write_block(host);
1508		break;
1509	case USDHI6_WAIT_FOR_DMA:
1510		usdhi6_dma_check_error(host);
1511		break;
1512	case USDHI6_WAIT_FOR_STOP:
1513		usdhi6_write(host, USDHI6_SD_STOP, 0);
1514		if (host->io_error) {
1515			int ret = usdhi6_error_code(host);
1516			if (mrq->stop)
1517				mrq->stop->error = ret;
1518			else
1519				mrq->data->error = ret;
1520			dev_warn(mmc_dev(host->mmc), "%s(): %d\n", __func__, ret);
1521			break;
1522		}
1523		usdhi6_resp_cmd12(host);
1524		mrq->stop->error = 0;
1525		break;
1526	case USDHI6_WAIT_FOR_DATA_END:
1527		if (host->io_error) {
1528			mrq->data->error = usdhi6_error_code(host);
1529			dev_warn(mmc_dev(host->mmc), "%s(): %d\n", __func__,
1530				 mrq->data->error);
1531		}
1532		break;
1533	default:
1534		cmd->error = -EFAULT;
1535		dev_err(mmc_dev(host->mmc), "Invalid state %u\n", host->wait);
1536		usdhi6_request_done(host);
1537		return IRQ_HANDLED;
1538	}
1539
1540	if (io_wait) {
1541		schedule_delayed_work(&host->timeout_work, host->timeout);
1542		/* Wait for more data or ACCESS_END */
1543		if (!host->dma_active)
1544			usdhi6_wait_for_brwe(host, mrq->data->flags & MMC_DATA_READ);
1545		return IRQ_HANDLED;
1546	}
1547
1548	if (!cmd->error) {
1549		if (data) {
1550			if (!data->error) {
1551				if (host->wait != USDHI6_WAIT_FOR_STOP &&
1552				    host->mrq->stop &&
1553				    !host->mrq->stop->error &&
1554				    !usdhi6_stop_cmd(host)) {
1555					/* Sending STOP */
1556					usdhi6_wait_for_resp(host);
1557
1558					schedule_delayed_work(&host->timeout_work,
1559							      host->timeout);
1560
1561					return IRQ_HANDLED;
1562				}
1563
1564				data->bytes_xfered = data->blocks * data->blksz;
1565			} else {
1566				/* Data error: might need to unmap the last page */
1567				dev_warn(mmc_dev(host->mmc), "%s(): data error %d\n",
1568					 __func__, data->error);
1569				usdhi6_sg_unmap(host, true);
1570			}
1571		} else if (cmd->opcode == MMC_APP_CMD) {
1572			host->app_cmd = true;
1573		}
1574	}
1575
1576	usdhi6_request_done(host);
1577
1578	return IRQ_HANDLED;
1579}
1580
1581static irqreturn_t usdhi6_sd(int irq, void *dev_id)
1582{
1583	struct usdhi6_host *host = dev_id;
1584	u16 status, status2, error;
1585
1586	status = usdhi6_read(host, USDHI6_SD_INFO1) & ~host->status_mask &
1587		~USDHI6_SD_INFO1_CARD;
1588	status2 = usdhi6_read(host, USDHI6_SD_INFO2) & ~host->status2_mask;
1589
1590	usdhi6_only_cd(host);
1591
1592	dev_dbg(mmc_dev(host->mmc),
1593		"IRQ status = 0x%08x, status2 = 0x%08x\n", status, status2);
1594
1595	if (!status && !status2)
1596		return IRQ_NONE;
1597
1598	error = status2 & USDHI6_SD_INFO2_ERR;
1599
1600	/* Ack / clear interrupts */
1601	if (USDHI6_SD_INFO1_IRQ & status)
1602		usdhi6_write(host, USDHI6_SD_INFO1,
1603			     0xffff & ~(USDHI6_SD_INFO1_IRQ & status));
1604
1605	if (USDHI6_SD_INFO2_IRQ & status2) {
1606		if (error)
1607			/* In error cases BWE and BRE aren't cleared automatically */
1608			status2 |= USDHI6_SD_INFO2_BWE | USDHI6_SD_INFO2_BRE;
1609
1610		usdhi6_write(host, USDHI6_SD_INFO2,
1611			     0xffff & ~(USDHI6_SD_INFO2_IRQ & status2));
1612	}
1613
1614	host->io_error = error;
1615	host->irq_status = status;
1616
1617	if (error) {
1618		/* Don't pollute the log with unsupported command timeouts */
1619		if (host->wait != USDHI6_WAIT_FOR_CMD ||
1620		    error != USDHI6_SD_INFO2_RSP_TOUT)
1621			dev_warn(mmc_dev(host->mmc),
1622				 "%s(): INFO2 error bits 0x%08x\n",
1623				 __func__, error);
1624		else
1625			dev_dbg(mmc_dev(host->mmc),
1626				"%s(): INFO2 error bits 0x%08x\n",
1627				__func__, error);
1628	}
1629
1630	return IRQ_WAKE_THREAD;
1631}
1632
1633static irqreturn_t usdhi6_sdio(int irq, void *dev_id)
1634{
1635	struct usdhi6_host *host = dev_id;
1636	u32 status = usdhi6_read(host, USDHI6_SDIO_INFO1) & ~host->sdio_mask;
1637
1638	dev_dbg(mmc_dev(host->mmc), "%s(): status 0x%x\n", __func__, status);
1639
1640	if (!status)
1641		return IRQ_NONE;
1642
1643	usdhi6_write(host, USDHI6_SDIO_INFO1, ~status);
1644
1645	mmc_signal_sdio_irq(host->mmc);
1646
1647	return IRQ_HANDLED;
1648}
1649
1650static irqreturn_t usdhi6_cd(int irq, void *dev_id)
1651{
1652	struct usdhi6_host *host = dev_id;
1653	struct mmc_host *mmc = host->mmc;
1654	u16 status;
1655
1656	/* We're only interested in hotplug events here */
1657	status = usdhi6_read(host, USDHI6_SD_INFO1) & ~host->status_mask &
1658		USDHI6_SD_INFO1_CARD;
1659
1660	if (!status)
1661		return IRQ_NONE;
1662
1663	/* Ack */
1664	usdhi6_write(host, USDHI6_SD_INFO1, ~status);
1665
1666	if (!work_pending(&mmc->detect.work) &&
1667	    (((status & USDHI6_SD_INFO1_CARD_INSERT) &&
1668	      !mmc->card) ||
1669	     ((status & USDHI6_SD_INFO1_CARD_EJECT) &&
1670	      mmc->card)))
1671		mmc_detect_change(mmc, msecs_to_jiffies(100));
1672
1673	return IRQ_HANDLED;
1674}
1675
1676/*
1677 * Actually this should not be needed, if the built-in timeout works reliably in
1678 * the both PIO cases and DMA never fails. But if DMA does fail, a timeout
1679 * handler might be the only way to catch the error.
1680 */
1681static void usdhi6_timeout_work(struct work_struct *work)
1682{
1683	struct delayed_work *d = to_delayed_work(work);
1684	struct usdhi6_host *host = container_of(d, struct usdhi6_host, timeout_work);
1685	struct mmc_request *mrq = host->mrq;
1686	struct mmc_data *data = mrq ? mrq->data : NULL;
1687	struct scatterlist *sg;
1688
1689	dev_warn(mmc_dev(host->mmc),
1690		 "%s timeout wait %u CMD%d: IRQ 0x%08x:0x%08x, last IRQ 0x%08x\n",
1691		 host->dma_active ? "DMA" : "PIO",
1692		 host->wait, mrq ? mrq->cmd->opcode : -1,
1693		 usdhi6_read(host, USDHI6_SD_INFO1),
1694		 usdhi6_read(host, USDHI6_SD_INFO2), host->irq_status);
1695
1696	if (host->dma_active) {
1697		usdhi6_dma_kill(host);
1698		usdhi6_dma_stop_unmap(host);
1699	}
1700
1701	switch (host->wait) {
1702	default:
1703		dev_err(mmc_dev(host->mmc), "Invalid state %u\n", host->wait);
1704		fallthrough;	/* mrq can be NULL, but is impossible */
1705	case USDHI6_WAIT_FOR_CMD:
1706		usdhi6_error_code(host);
1707		if (mrq)
1708			mrq->cmd->error = -ETIMEDOUT;
1709		break;
1710	case USDHI6_WAIT_FOR_STOP:
1711		usdhi6_error_code(host);
1712		mrq->stop->error = -ETIMEDOUT;
1713		break;
1714	case USDHI6_WAIT_FOR_DMA:
1715	case USDHI6_WAIT_FOR_MREAD:
1716	case USDHI6_WAIT_FOR_MWRITE:
1717	case USDHI6_WAIT_FOR_READ:
1718	case USDHI6_WAIT_FOR_WRITE:
1719		sg = host->sg ?: data->sg;
1720		dev_dbg(mmc_dev(host->mmc),
1721			"%c: page #%u @ +0x%zx %ux%u in SG%u. Current SG %u bytes @ %u\n",
1722			data->flags & MMC_DATA_READ ? 'R' : 'W', host->page_idx,
1723			host->offset, data->blocks, data->blksz, data->sg_len,
1724			sg_dma_len(sg), sg->offset);
1725		usdhi6_sg_unmap(host, true);
1726		fallthrough;	/* page unmapped in USDHI6_WAIT_FOR_DATA_END */
1727	case USDHI6_WAIT_FOR_DATA_END:
1728		usdhi6_error_code(host);
1729		data->error = -ETIMEDOUT;
1730	}
1731
1732	if (mrq)
1733		usdhi6_request_done(host);
1734}
1735
1736/*			 Probe / release				*/
1737
1738static const struct of_device_id usdhi6_of_match[] = {
1739	{.compatible = "renesas,usdhi6rol0"},
1740	{}
1741};
1742MODULE_DEVICE_TABLE(of, usdhi6_of_match);
1743
1744static int usdhi6_probe(struct platform_device *pdev)
1745{
1746	struct device *dev = &pdev->dev;
1747	struct mmc_host *mmc;
1748	struct usdhi6_host *host;
1749	struct resource *res;
1750	int irq_cd, irq_sd, irq_sdio;
1751	u32 version;
1752	int ret;
1753
1754	if (!dev->of_node)
1755		return -ENODEV;
1756
1757	irq_cd = platform_get_irq_byname(pdev, "card detect");
1758	irq_sd = platform_get_irq_byname(pdev, "data");
1759	irq_sdio = platform_get_irq_byname(pdev, "SDIO");
1760	if (irq_sd < 0)
1761		return irq_sd;
1762	if (irq_sdio < 0)
1763		return irq_sdio;
1764
1765	mmc = mmc_alloc_host(sizeof(struct usdhi6_host), dev);
1766	if (!mmc)
1767		return -ENOMEM;
1768
1769	ret = mmc_regulator_get_supply(mmc);
1770	if (ret)
1771		goto e_free_mmc;
1772
1773	ret = mmc_of_parse(mmc);
1774	if (ret < 0)
1775		goto e_free_mmc;
1776
1777	host		= mmc_priv(mmc);
1778	host->mmc	= mmc;
1779	host->wait	= USDHI6_WAIT_FOR_REQUEST;
1780	host->timeout	= msecs_to_jiffies(USDHI6_REQ_TIMEOUT_MS);
1781	/*
1782	 * We use a fixed timeout of 4s, hence inform the core about it. A
1783	 * future improvement should instead respect the cmd->busy_timeout.
1784	 */
1785	mmc->max_busy_timeout = USDHI6_REQ_TIMEOUT_MS;
1786
1787	host->pinctrl = devm_pinctrl_get(&pdev->dev);
1788	if (IS_ERR(host->pinctrl)) {
1789		ret = PTR_ERR(host->pinctrl);
1790		goto e_free_mmc;
1791	}
1792
1793	host->pins_uhs = pinctrl_lookup_state(host->pinctrl, "state_uhs");
1794
1795	host->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1796	if (IS_ERR(host->base)) {
1797		ret = PTR_ERR(host->base);
1798		goto e_free_mmc;
1799	}
1800
1801	host->clk = devm_clk_get(dev, NULL);
1802	if (IS_ERR(host->clk)) {
1803		ret = PTR_ERR(host->clk);
1804		goto e_free_mmc;
1805	}
1806
1807	host->imclk = clk_get_rate(host->clk);
1808
1809	ret = clk_prepare_enable(host->clk);
1810	if (ret < 0)
1811		goto e_free_mmc;
1812
1813	version = usdhi6_read(host, USDHI6_VERSION);
1814	if ((version & 0xfff) != 0xa0d) {
1815		ret = -EPERM;
1816		dev_err(dev, "Version not recognized %x\n", version);
1817		goto e_clk_off;
1818	}
1819
1820	dev_info(dev, "A USDHI6ROL0 SD host detected with %d ports\n",
1821		 usdhi6_read(host, USDHI6_SD_PORT_SEL) >> USDHI6_SD_PORT_SEL_PORTS_SHIFT);
1822
1823	usdhi6_mask_all(host);
1824
1825	if (irq_cd >= 0) {
1826		ret = devm_request_irq(dev, irq_cd, usdhi6_cd, 0,
1827				       dev_name(dev), host);
1828		if (ret < 0)
1829			goto e_clk_off;
1830	} else {
1831		mmc->caps |= MMC_CAP_NEEDS_POLL;
1832	}
1833
1834	ret = devm_request_threaded_irq(dev, irq_sd, usdhi6_sd, usdhi6_sd_bh, 0,
1835			       dev_name(dev), host);
1836	if (ret < 0)
1837		goto e_clk_off;
1838
1839	ret = devm_request_irq(dev, irq_sdio, usdhi6_sdio, 0,
1840			       dev_name(dev), host);
1841	if (ret < 0)
1842		goto e_clk_off;
1843
1844	INIT_DELAYED_WORK(&host->timeout_work, usdhi6_timeout_work);
1845
1846	usdhi6_dma_request(host, res->start);
1847
1848	mmc->ops = &usdhi6_ops;
1849	mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
1850		     MMC_CAP_SDIO_IRQ;
1851	/* Set .max_segs to some random number. Feel free to adjust. */
1852	mmc->max_segs = 32;
1853	mmc->max_blk_size = 512;
1854	mmc->max_req_size = PAGE_SIZE * mmc->max_segs;
1855	mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
1856	/*
1857	 * Setting .max_seg_size to 1 page would simplify our page-mapping code,
1858	 * But OTOH, having large segments makes DMA more efficient. We could
1859	 * check, whether we managed to get DMA and fall back to 1 page
1860	 * segments, but if we do manage to obtain DMA and then it fails at
1861	 * run-time and we fall back to PIO, we will continue getting large
1862	 * segments. So, we wouldn't be able to get rid of the code anyway.
1863	 */
1864	mmc->max_seg_size = mmc->max_req_size;
1865	if (!mmc->f_max)
1866		mmc->f_max = host->imclk;
1867	mmc->f_min = host->imclk / 512;
1868
1869	platform_set_drvdata(pdev, host);
1870
1871	ret = mmc_add_host(mmc);
1872	if (ret < 0)
1873		goto e_release_dma;
1874
1875	return 0;
1876
1877e_release_dma:
1878	usdhi6_dma_release(host);
1879e_clk_off:
1880	clk_disable_unprepare(host->clk);
1881e_free_mmc:
1882	mmc_free_host(mmc);
1883
1884	return ret;
1885}
1886
1887static void usdhi6_remove(struct platform_device *pdev)
1888{
1889	struct usdhi6_host *host = platform_get_drvdata(pdev);
1890
1891	mmc_remove_host(host->mmc);
1892
1893	usdhi6_mask_all(host);
1894	cancel_delayed_work_sync(&host->timeout_work);
1895	usdhi6_dma_release(host);
1896	clk_disable_unprepare(host->clk);
1897	mmc_free_host(host->mmc);
1898}
1899
1900static struct platform_driver usdhi6_driver = {
1901	.probe		= usdhi6_probe,
1902	.remove_new	= usdhi6_remove,
1903	.driver		= {
1904		.name	= "usdhi6rol0",
1905		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1906		.of_match_table = usdhi6_of_match,
1907	},
1908};
1909
1910module_platform_driver(usdhi6_driver);
1911
1912MODULE_DESCRIPTION("Renesas usdhi6rol0 SD/SDIO host driver");
1913MODULE_LICENSE("GPL v2");
1914MODULE_ALIAS("platform:usdhi6rol0");
1915MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
1916