xref: /linux/drivers/mmc/host/usdhi6rol0.c (revision c0c914eca7f251c70facc37dfebeaf176601918d)
1 /*
2  * Copyright (C) 2013-2014 Renesas Electronics Europe Ltd.
3  * Author: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of version 2 of the GNU General Public License as
7  * published by the Free Software Foundation.
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/dmaengine.h>
15 #include <linux/highmem.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/log2.h>
19 #include <linux/mmc/host.h>
20 #include <linux/mmc/mmc.h>
21 #include <linux/mmc/sd.h>
22 #include <linux/mmc/sdio.h>
23 #include <linux/module.h>
24 #include <linux/pagemap.h>
25 #include <linux/platform_device.h>
26 #include <linux/scatterlist.h>
27 #include <linux/string.h>
28 #include <linux/time.h>
29 #include <linux/virtio.h>
30 #include <linux/workqueue.h>
31 
32 #define USDHI6_SD_CMD		0x0000
33 #define USDHI6_SD_PORT_SEL	0x0004
34 #define USDHI6_SD_ARG		0x0008
35 #define USDHI6_SD_STOP		0x0010
36 #define USDHI6_SD_SECCNT	0x0014
37 #define USDHI6_SD_RSP10		0x0018
38 #define USDHI6_SD_RSP32		0x0020
39 #define USDHI6_SD_RSP54		0x0028
40 #define USDHI6_SD_RSP76		0x0030
41 #define USDHI6_SD_INFO1		0x0038
42 #define USDHI6_SD_INFO2		0x003c
43 #define USDHI6_SD_INFO1_MASK	0x0040
44 #define USDHI6_SD_INFO2_MASK	0x0044
45 #define USDHI6_SD_CLK_CTRL	0x0048
46 #define USDHI6_SD_SIZE		0x004c
47 #define USDHI6_SD_OPTION	0x0050
48 #define USDHI6_SD_ERR_STS1	0x0058
49 #define USDHI6_SD_ERR_STS2	0x005c
50 #define USDHI6_SD_BUF0		0x0060
51 #define USDHI6_SDIO_MODE	0x0068
52 #define USDHI6_SDIO_INFO1	0x006c
53 #define USDHI6_SDIO_INFO1_MASK	0x0070
54 #define USDHI6_CC_EXT_MODE	0x01b0
55 #define USDHI6_SOFT_RST		0x01c0
56 #define USDHI6_VERSION		0x01c4
57 #define USDHI6_HOST_MODE	0x01c8
58 #define USDHI6_SDIF_MODE	0x01cc
59 
60 #define USDHI6_SD_CMD_APP		0x0040
61 #define USDHI6_SD_CMD_MODE_RSP_AUTO	0x0000
62 #define USDHI6_SD_CMD_MODE_RSP_NONE	0x0300
63 #define USDHI6_SD_CMD_MODE_RSP_R1	0x0400	/* Also R5, R6, R7 */
64 #define USDHI6_SD_CMD_MODE_RSP_R1B	0x0500	/* R1b */
65 #define USDHI6_SD_CMD_MODE_RSP_R2	0x0600
66 #define USDHI6_SD_CMD_MODE_RSP_R3	0x0700	/* Also R4 */
67 #define USDHI6_SD_CMD_DATA		0x0800
68 #define USDHI6_SD_CMD_READ		0x1000
69 #define USDHI6_SD_CMD_MULTI		0x2000
70 #define USDHI6_SD_CMD_CMD12_AUTO_OFF	0x4000
71 
72 #define USDHI6_CC_EXT_MODE_SDRW		BIT(1)
73 
74 #define USDHI6_SD_INFO1_RSP_END		BIT(0)
75 #define USDHI6_SD_INFO1_ACCESS_END	BIT(2)
76 #define USDHI6_SD_INFO1_CARD_OUT	BIT(3)
77 #define USDHI6_SD_INFO1_CARD_IN		BIT(4)
78 #define USDHI6_SD_INFO1_CD		BIT(5)
79 #define USDHI6_SD_INFO1_WP		BIT(7)
80 #define USDHI6_SD_INFO1_D3_CARD_OUT	BIT(8)
81 #define USDHI6_SD_INFO1_D3_CARD_IN	BIT(9)
82 
83 #define USDHI6_SD_INFO2_CMD_ERR		BIT(0)
84 #define USDHI6_SD_INFO2_CRC_ERR		BIT(1)
85 #define USDHI6_SD_INFO2_END_ERR		BIT(2)
86 #define USDHI6_SD_INFO2_TOUT		BIT(3)
87 #define USDHI6_SD_INFO2_IWA_ERR		BIT(4)
88 #define USDHI6_SD_INFO2_IRA_ERR		BIT(5)
89 #define USDHI6_SD_INFO2_RSP_TOUT	BIT(6)
90 #define USDHI6_SD_INFO2_SDDAT0		BIT(7)
91 #define USDHI6_SD_INFO2_BRE		BIT(8)
92 #define USDHI6_SD_INFO2_BWE		BIT(9)
93 #define USDHI6_SD_INFO2_SCLKDIVEN	BIT(13)
94 #define USDHI6_SD_INFO2_CBSY		BIT(14)
95 #define USDHI6_SD_INFO2_ILA		BIT(15)
96 
97 #define USDHI6_SD_INFO1_CARD_INSERT (USDHI6_SD_INFO1_CARD_IN | USDHI6_SD_INFO1_D3_CARD_IN)
98 #define USDHI6_SD_INFO1_CARD_EJECT (USDHI6_SD_INFO1_CARD_OUT | USDHI6_SD_INFO1_D3_CARD_OUT)
99 #define USDHI6_SD_INFO1_CARD (USDHI6_SD_INFO1_CARD_INSERT | USDHI6_SD_INFO1_CARD_EJECT)
100 #define USDHI6_SD_INFO1_CARD_CD (USDHI6_SD_INFO1_CARD_IN | USDHI6_SD_INFO1_CARD_OUT)
101 
102 #define USDHI6_SD_INFO2_ERR	(USDHI6_SD_INFO2_CMD_ERR |	\
103 	USDHI6_SD_INFO2_CRC_ERR | USDHI6_SD_INFO2_END_ERR |	\
104 	USDHI6_SD_INFO2_TOUT | USDHI6_SD_INFO2_IWA_ERR |	\
105 	USDHI6_SD_INFO2_IRA_ERR | USDHI6_SD_INFO2_RSP_TOUT |	\
106 	USDHI6_SD_INFO2_ILA)
107 
108 #define USDHI6_SD_INFO1_IRQ	(USDHI6_SD_INFO1_RSP_END | USDHI6_SD_INFO1_ACCESS_END | \
109 				 USDHI6_SD_INFO1_CARD)
110 
111 #define USDHI6_SD_INFO2_IRQ	(USDHI6_SD_INFO2_ERR | USDHI6_SD_INFO2_BRE | \
112 				 USDHI6_SD_INFO2_BWE | 0x0800 | USDHI6_SD_INFO2_ILA)
113 
114 #define USDHI6_SD_CLK_CTRL_SCLKEN	BIT(8)
115 
116 #define USDHI6_SD_STOP_STP		BIT(0)
117 #define USDHI6_SD_STOP_SEC		BIT(8)
118 
119 #define USDHI6_SDIO_INFO1_IOIRQ		BIT(0)
120 #define USDHI6_SDIO_INFO1_EXPUB52	BIT(14)
121 #define USDHI6_SDIO_INFO1_EXWT		BIT(15)
122 
123 #define USDHI6_SD_ERR_STS1_CRC_NO_ERROR	BIT(13)
124 
125 #define USDHI6_SOFT_RST_RESERVED	(BIT(1) | BIT(2))
126 #define USDHI6_SOFT_RST_RESET		BIT(0)
127 
128 #define USDHI6_SD_OPTION_TIMEOUT_SHIFT	4
129 #define USDHI6_SD_OPTION_TIMEOUT_MASK	(0xf << USDHI6_SD_OPTION_TIMEOUT_SHIFT)
130 #define USDHI6_SD_OPTION_WIDTH_1	BIT(15)
131 
132 #define USDHI6_SD_PORT_SEL_PORTS_SHIFT	8
133 
134 #define USDHI6_SD_CLK_CTRL_DIV_MASK	0xff
135 
136 #define USDHI6_SDIO_INFO1_IRQ	(USDHI6_SDIO_INFO1_IOIRQ | 3 | \
137 				 USDHI6_SDIO_INFO1_EXPUB52 | USDHI6_SDIO_INFO1_EXWT)
138 
139 #define USDHI6_MIN_DMA 64
140 
141 enum 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 
153 struct usdhi6_page {
154 	struct page *page;
155 	void *mapped;		/* mapped page */
156 };
157 
158 struct 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 
203 /*			I/O primitives					*/
204 
205 static void usdhi6_write(struct usdhi6_host *host, u32 reg, u32 data)
206 {
207 	iowrite32(data, host->base + reg);
208 	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
209 		host->base, reg, data);
210 }
211 
212 static void usdhi6_write16(struct usdhi6_host *host, u32 reg, u16 data)
213 {
214 	iowrite16(data, host->base + reg);
215 	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
216 		host->base, reg, data);
217 }
218 
219 static u32 usdhi6_read(struct usdhi6_host *host, u32 reg)
220 {
221 	u32 data = ioread32(host->base + reg);
222 	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
223 		host->base, reg, data);
224 	return data;
225 }
226 
227 static u16 usdhi6_read16(struct usdhi6_host *host, u32 reg)
228 {
229 	u16 data = ioread16(host->base + reg);
230 	dev_vdbg(mmc_dev(host->mmc), "%s(0x%p + 0x%x) = 0x%x\n", __func__,
231 		host->base, reg, data);
232 	return data;
233 }
234 
235 static void usdhi6_irq_enable(struct usdhi6_host *host, u32 info1, u32 info2)
236 {
237 	host->status_mask = USDHI6_SD_INFO1_IRQ & ~info1;
238 	host->status2_mask = USDHI6_SD_INFO2_IRQ & ~info2;
239 	usdhi6_write(host, USDHI6_SD_INFO1_MASK, host->status_mask);
240 	usdhi6_write(host, USDHI6_SD_INFO2_MASK, host->status2_mask);
241 }
242 
243 static void usdhi6_wait_for_resp(struct usdhi6_host *host)
244 {
245 	usdhi6_irq_enable(host, USDHI6_SD_INFO1_RSP_END |
246 			  USDHI6_SD_INFO1_ACCESS_END | USDHI6_SD_INFO1_CARD_CD,
247 			  USDHI6_SD_INFO2_ERR);
248 }
249 
250 static void usdhi6_wait_for_brwe(struct usdhi6_host *host, bool read)
251 {
252 	usdhi6_irq_enable(host, USDHI6_SD_INFO1_ACCESS_END |
253 			  USDHI6_SD_INFO1_CARD_CD, USDHI6_SD_INFO2_ERR |
254 			  (read ? USDHI6_SD_INFO2_BRE : USDHI6_SD_INFO2_BWE));
255 }
256 
257 static void usdhi6_only_cd(struct usdhi6_host *host)
258 {
259 	/* Mask all except card hotplug */
260 	usdhi6_irq_enable(host, USDHI6_SD_INFO1_CARD_CD, 0);
261 }
262 
263 static void usdhi6_mask_all(struct usdhi6_host *host)
264 {
265 	usdhi6_irq_enable(host, 0, 0);
266 }
267 
268 static int usdhi6_error_code(struct usdhi6_host *host)
269 {
270 	u32 err;
271 
272 	usdhi6_write(host, USDHI6_SD_STOP, USDHI6_SD_STOP_STP);
273 
274 	if (host->io_error &
275 	    (USDHI6_SD_INFO2_RSP_TOUT | USDHI6_SD_INFO2_TOUT)) {
276 		u32 rsp54 = usdhi6_read(host, USDHI6_SD_RSP54);
277 		int opc = host->mrq ? host->mrq->cmd->opcode : -1;
278 
279 		err = usdhi6_read(host, USDHI6_SD_ERR_STS2);
280 		/* Response timeout is often normal, don't spam the log */
281 		if (host->wait == USDHI6_WAIT_FOR_CMD)
282 			dev_dbg(mmc_dev(host->mmc),
283 				"T-out sts 0x%x, resp 0x%x, state %u, CMD%d\n",
284 				err, rsp54, host->wait, opc);
285 		else
286 			dev_warn(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 		return -ETIMEDOUT;
290 	}
291 
292 	err = usdhi6_read(host, USDHI6_SD_ERR_STS1);
293 	if (err != USDHI6_SD_ERR_STS1_CRC_NO_ERROR)
294 		dev_warn(mmc_dev(host->mmc), "Err sts 0x%x, state %u, CMD%d\n",
295 			 err, host->wait, host->mrq ? host->mrq->cmd->opcode : -1);
296 	if (host->io_error & USDHI6_SD_INFO2_ILA)
297 		return -EILSEQ;
298 
299 	return -EIO;
300 }
301 
302 /*			Scatter-Gather management			*/
303 
304 /*
305  * In PIO mode we have to map each page separately, using kmap(). That way
306  * adjacent pages are mapped to non-adjacent virtual addresses. That's why we
307  * have to use a bounce buffer for blocks, crossing page boundaries. Such blocks
308  * have been observed with an SDIO WiFi card (b43 driver).
309  */
310 static void usdhi6_blk_bounce(struct usdhi6_host *host,
311 			      struct scatterlist *sg)
312 {
313 	struct mmc_data *data = host->mrq->data;
314 	size_t blk_head = host->head_len;
315 
316 	dev_dbg(mmc_dev(host->mmc), "%s(): CMD%u of %u SG: %ux%u @ 0x%x\n",
317 		__func__, host->mrq->cmd->opcode, data->sg_len,
318 		data->blksz, data->blocks, sg->offset);
319 
320 	host->head_pg.page	= host->pg.page;
321 	host->head_pg.mapped	= host->pg.mapped;
322 	host->pg.page		= nth_page(host->pg.page, 1);
323 	host->pg.mapped		= kmap(host->pg.page);
324 
325 	host->blk_page = host->bounce_buf;
326 	host->offset = 0;
327 
328 	if (data->flags & MMC_DATA_READ)
329 		return;
330 
331 	memcpy(host->bounce_buf, host->head_pg.mapped + PAGE_SIZE - blk_head,
332 	       blk_head);
333 	memcpy(host->bounce_buf + blk_head, host->pg.mapped,
334 	       data->blksz - blk_head);
335 }
336 
337 /* Only called for multiple block IO */
338 static void usdhi6_sg_prep(struct usdhi6_host *host)
339 {
340 	struct mmc_request *mrq = host->mrq;
341 	struct mmc_data *data = mrq->data;
342 
343 	usdhi6_write(host, USDHI6_SD_SECCNT, data->blocks);
344 
345 	host->sg = data->sg;
346 	/* TODO: if we always map, this is redundant */
347 	host->offset = host->sg->offset;
348 }
349 
350 /* Map the first page in an SG segment: common for multiple and single block IO */
351 static void *usdhi6_sg_map(struct usdhi6_host *host)
352 {
353 	struct mmc_data *data = host->mrq->data;
354 	struct scatterlist *sg = data->sg_len > 1 ? host->sg : data->sg;
355 	size_t head = PAGE_SIZE - sg->offset;
356 	size_t blk_head = head % data->blksz;
357 
358 	WARN(host->pg.page, "%p not properly unmapped!\n", host->pg.page);
359 	if (WARN(sg_dma_len(sg) % data->blksz,
360 		 "SG size %u isn't a multiple of block size %u\n",
361 		 sg_dma_len(sg), data->blksz))
362 		return NULL;
363 
364 	host->pg.page = sg_page(sg);
365 	host->pg.mapped = kmap(host->pg.page);
366 	host->offset = sg->offset;
367 
368 	/*
369 	 * Block size must be a power of 2 for multi-block transfers,
370 	 * therefore blk_head is equal for all pages in this SG
371 	 */
372 	host->head_len = blk_head;
373 
374 	if (head < data->blksz)
375 		/*
376 		 * The first block in the SG crosses a page boundary.
377 		 * Max blksz = 512, so blocks can only span 2 pages
378 		 */
379 		usdhi6_blk_bounce(host, sg);
380 	else
381 		host->blk_page = host->pg.mapped;
382 
383 	dev_dbg(mmc_dev(host->mmc), "Mapped %p (%lx) at %p + %u for CMD%u @ 0x%p\n",
384 		host->pg.page, page_to_pfn(host->pg.page), host->pg.mapped,
385 		sg->offset, host->mrq->cmd->opcode, host->mrq);
386 
387 	return host->blk_page + host->offset;
388 }
389 
390 /* Unmap the current page: common for multiple and single block IO */
391 static void usdhi6_sg_unmap(struct usdhi6_host *host, bool force)
392 {
393 	struct mmc_data *data = host->mrq->data;
394 	struct page *page = host->head_pg.page;
395 
396 	if (page) {
397 		/* Previous block was cross-page boundary */
398 		struct scatterlist *sg = data->sg_len > 1 ?
399 			host->sg : data->sg;
400 		size_t blk_head = host->head_len;
401 
402 		if (!data->error && data->flags & MMC_DATA_READ) {
403 			memcpy(host->head_pg.mapped + PAGE_SIZE - blk_head,
404 			       host->bounce_buf, blk_head);
405 			memcpy(host->pg.mapped, host->bounce_buf + blk_head,
406 			       data->blksz - blk_head);
407 		}
408 
409 		flush_dcache_page(page);
410 		kunmap(page);
411 
412 		host->head_pg.page = NULL;
413 
414 		if (!force && sg_dma_len(sg) + sg->offset >
415 		    (host->page_idx << PAGE_SHIFT) + data->blksz - blk_head)
416 			/* More blocks in this SG, don't unmap the next page */
417 			return;
418 	}
419 
420 	page = host->pg.page;
421 	if (!page)
422 		return;
423 
424 	flush_dcache_page(page);
425 	kunmap(page);
426 
427 	host->pg.page = NULL;
428 }
429 
430 /* Called from MMC_WRITE_MULTIPLE_BLOCK or MMC_READ_MULTIPLE_BLOCK */
431 static void usdhi6_sg_advance(struct usdhi6_host *host)
432 {
433 	struct mmc_data *data = host->mrq->data;
434 	size_t done, total;
435 
436 	/* New offset: set at the end of the previous block */
437 	if (host->head_pg.page) {
438 		/* Finished a cross-page block, jump to the new page */
439 		host->page_idx++;
440 		host->offset = data->blksz - host->head_len;
441 		host->blk_page = host->pg.mapped;
442 		usdhi6_sg_unmap(host, false);
443 	} else {
444 		host->offset += data->blksz;
445 		/* The completed block didn't cross a page boundary */
446 		if (host->offset == PAGE_SIZE) {
447 			/* If required, we'll map the page below */
448 			host->offset = 0;
449 			host->page_idx++;
450 		}
451 	}
452 
453 	/*
454 	 * Now host->blk_page + host->offset point at the end of our last block
455 	 * and host->page_idx is the index of the page, in which our new block
456 	 * is located, if any
457 	 */
458 
459 	done = (host->page_idx << PAGE_SHIFT) + host->offset;
460 	total = host->sg->offset + sg_dma_len(host->sg);
461 
462 	dev_dbg(mmc_dev(host->mmc), "%s(): %zu of %zu @ %zu\n", __func__,
463 		done, total, host->offset);
464 
465 	if (done < total && host->offset) {
466 		/* More blocks in this page */
467 		if (host->offset + data->blksz > PAGE_SIZE)
468 			/* We approached at a block, that spans 2 pages */
469 			usdhi6_blk_bounce(host, host->sg);
470 
471 		return;
472 	}
473 
474 	/* Finished current page or an SG segment */
475 	usdhi6_sg_unmap(host, false);
476 
477 	if (done == total) {
478 		/*
479 		 * End of an SG segment or the complete SG: jump to the next
480 		 * segment, we'll map it later in usdhi6_blk_read() or
481 		 * usdhi6_blk_write()
482 		 */
483 		struct scatterlist *next = sg_next(host->sg);
484 
485 		host->page_idx = 0;
486 
487 		if (!next)
488 			host->wait = USDHI6_WAIT_FOR_DATA_END;
489 		host->sg = next;
490 
491 		if (WARN(next && sg_dma_len(next) % data->blksz,
492 			 "SG size %u isn't a multiple of block size %u\n",
493 			 sg_dma_len(next), data->blksz))
494 			data->error = -EINVAL;
495 
496 		return;
497 	}
498 
499 	/* We cannot get here after crossing a page border */
500 
501 	/* Next page in the same SG */
502 	host->pg.page = nth_page(sg_page(host->sg), host->page_idx);
503 	host->pg.mapped = kmap(host->pg.page);
504 	host->blk_page = host->pg.mapped;
505 
506 	dev_dbg(mmc_dev(host->mmc), "Mapped %p (%lx) at %p for CMD%u @ 0x%p\n",
507 		host->pg.page, page_to_pfn(host->pg.page), host->pg.mapped,
508 		host->mrq->cmd->opcode, host->mrq);
509 }
510 
511 /*			DMA handling					*/
512 
513 static void usdhi6_dma_release(struct usdhi6_host *host)
514 {
515 	host->dma_active = false;
516 	if (host->chan_tx) {
517 		struct dma_chan *chan = host->chan_tx;
518 		host->chan_tx = NULL;
519 		dma_release_channel(chan);
520 	}
521 	if (host->chan_rx) {
522 		struct dma_chan *chan = host->chan_rx;
523 		host->chan_rx = NULL;
524 		dma_release_channel(chan);
525 	}
526 }
527 
528 static void usdhi6_dma_stop_unmap(struct usdhi6_host *host)
529 {
530 	struct mmc_data *data = host->mrq->data;
531 
532 	if (!host->dma_active)
533 		return;
534 
535 	usdhi6_write(host, USDHI6_CC_EXT_MODE, 0);
536 	host->dma_active = false;
537 
538 	if (data->flags & MMC_DATA_READ)
539 		dma_unmap_sg(host->chan_rx->device->dev, data->sg,
540 			     data->sg_len, DMA_FROM_DEVICE);
541 	else
542 		dma_unmap_sg(host->chan_tx->device->dev, data->sg,
543 			     data->sg_len, DMA_TO_DEVICE);
544 }
545 
546 static void usdhi6_dma_complete(void *arg)
547 {
548 	struct usdhi6_host *host = arg;
549 	struct mmc_request *mrq = host->mrq;
550 
551 	if (WARN(!mrq || !mrq->data, "%s: NULL data in DMA completion for %p!\n",
552 		 dev_name(mmc_dev(host->mmc)), mrq))
553 		return;
554 
555 	dev_dbg(mmc_dev(host->mmc), "%s(): CMD%u DMA completed\n", __func__,
556 		mrq->cmd->opcode);
557 
558 	usdhi6_dma_stop_unmap(host);
559 	usdhi6_wait_for_brwe(host, mrq->data->flags & MMC_DATA_READ);
560 }
561 
562 static int usdhi6_dma_setup(struct usdhi6_host *host, struct dma_chan *chan,
563 			    enum dma_transfer_direction dir)
564 {
565 	struct mmc_data *data = host->mrq->data;
566 	struct scatterlist *sg = data->sg;
567 	struct dma_async_tx_descriptor *desc = NULL;
568 	dma_cookie_t cookie = -EINVAL;
569 	enum dma_data_direction data_dir;
570 	int ret;
571 
572 	switch (dir) {
573 	case DMA_MEM_TO_DEV:
574 		data_dir = DMA_TO_DEVICE;
575 		break;
576 	case DMA_DEV_TO_MEM:
577 		data_dir = DMA_FROM_DEVICE;
578 		break;
579 	default:
580 		return -EINVAL;
581 	}
582 
583 	ret = dma_map_sg(chan->device->dev, sg, data->sg_len, data_dir);
584 	if (ret > 0) {
585 		host->dma_active = true;
586 		desc = dmaengine_prep_slave_sg(chan, sg, ret, dir,
587 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
588 	}
589 
590 	if (desc) {
591 		desc->callback = usdhi6_dma_complete;
592 		desc->callback_param = host;
593 		cookie = dmaengine_submit(desc);
594 	}
595 
596 	dev_dbg(mmc_dev(host->mmc), "%s(): mapped %d -> %d, cookie %d @ %p\n",
597 		__func__, data->sg_len, ret, cookie, desc);
598 
599 	if (cookie < 0) {
600 		/* DMA failed, fall back to PIO */
601 		if (ret >= 0)
602 			ret = cookie;
603 		usdhi6_dma_release(host);
604 		dev_warn(mmc_dev(host->mmc),
605 			 "DMA failed: %d, falling back to PIO\n", ret);
606 	}
607 
608 	return cookie;
609 }
610 
611 static int usdhi6_dma_start(struct usdhi6_host *host)
612 {
613 	if (!host->chan_rx || !host->chan_tx)
614 		return -ENODEV;
615 
616 	if (host->mrq->data->flags & MMC_DATA_READ)
617 		return usdhi6_dma_setup(host, host->chan_rx, DMA_DEV_TO_MEM);
618 
619 	return usdhi6_dma_setup(host, host->chan_tx, DMA_MEM_TO_DEV);
620 }
621 
622 static void usdhi6_dma_kill(struct usdhi6_host *host)
623 {
624 	struct mmc_data *data = host->mrq->data;
625 
626 	dev_dbg(mmc_dev(host->mmc), "%s(): SG of %u: %ux%u\n",
627 		__func__, data->sg_len, data->blocks, data->blksz);
628 	/* Abort DMA */
629 	if (data->flags & MMC_DATA_READ)
630 		dmaengine_terminate_all(host->chan_rx);
631 	else
632 		dmaengine_terminate_all(host->chan_tx);
633 }
634 
635 static void usdhi6_dma_check_error(struct usdhi6_host *host)
636 {
637 	struct mmc_data *data = host->mrq->data;
638 
639 	dev_dbg(mmc_dev(host->mmc), "%s(): IO error %d, status 0x%x\n",
640 		__func__, host->io_error, usdhi6_read(host, USDHI6_SD_INFO1));
641 
642 	if (host->io_error) {
643 		data->error = usdhi6_error_code(host);
644 		data->bytes_xfered = 0;
645 		usdhi6_dma_kill(host);
646 		usdhi6_dma_release(host);
647 		dev_warn(mmc_dev(host->mmc),
648 			 "DMA failed: %d, falling back to PIO\n", data->error);
649 		return;
650 	}
651 
652 	/*
653 	 * The datasheet tells us to check a response from the card, whereas
654 	 * responses only come after the command phase, not after the data
655 	 * phase. Let's check anyway.
656 	 */
657 	if (host->irq_status & USDHI6_SD_INFO1_RSP_END)
658 		dev_warn(mmc_dev(host->mmc), "Unexpected response received!\n");
659 }
660 
661 static void usdhi6_dma_kick(struct usdhi6_host *host)
662 {
663 	if (host->mrq->data->flags & MMC_DATA_READ)
664 		dma_async_issue_pending(host->chan_rx);
665 	else
666 		dma_async_issue_pending(host->chan_tx);
667 }
668 
669 static void usdhi6_dma_request(struct usdhi6_host *host, phys_addr_t start)
670 {
671 	struct dma_slave_config cfg = {
672 		.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
673 		.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES,
674 	};
675 	int ret;
676 
677 	host->chan_tx = dma_request_slave_channel(mmc_dev(host->mmc), "tx");
678 	dev_dbg(mmc_dev(host->mmc), "%s: TX: got channel %p\n", __func__,
679 		host->chan_tx);
680 
681 	if (!host->chan_tx)
682 		return;
683 
684 	cfg.direction = DMA_MEM_TO_DEV;
685 	cfg.dst_addr = start + USDHI6_SD_BUF0;
686 	cfg.dst_maxburst = 128;	/* 128 words * 4 bytes = 512 bytes */
687 	cfg.src_addr = 0;
688 	ret = dmaengine_slave_config(host->chan_tx, &cfg);
689 	if (ret < 0)
690 		goto e_release_tx;
691 
692 	host->chan_rx = dma_request_slave_channel(mmc_dev(host->mmc), "rx");
693 	dev_dbg(mmc_dev(host->mmc), "%s: RX: got channel %p\n", __func__,
694 		host->chan_rx);
695 
696 	if (!host->chan_rx)
697 		goto e_release_tx;
698 
699 	cfg.direction = DMA_DEV_TO_MEM;
700 	cfg.src_addr = cfg.dst_addr;
701 	cfg.src_maxburst = 128;	/* 128 words * 4 bytes = 512 bytes */
702 	cfg.dst_addr = 0;
703 	ret = dmaengine_slave_config(host->chan_rx, &cfg);
704 	if (ret < 0)
705 		goto e_release_rx;
706 
707 	return;
708 
709 e_release_rx:
710 	dma_release_channel(host->chan_rx);
711 	host->chan_rx = NULL;
712 e_release_tx:
713 	dma_release_channel(host->chan_tx);
714 	host->chan_tx = NULL;
715 }
716 
717 /*			API helpers					*/
718 
719 static void usdhi6_clk_set(struct usdhi6_host *host, struct mmc_ios *ios)
720 {
721 	unsigned long rate = ios->clock;
722 	u32 val;
723 	unsigned int i;
724 
725 	for (i = 1000; i; i--) {
726 		if (usdhi6_read(host, USDHI6_SD_INFO2) & USDHI6_SD_INFO2_SCLKDIVEN)
727 			break;
728 		usleep_range(10, 100);
729 	}
730 
731 	if (!i) {
732 		dev_err(mmc_dev(host->mmc), "SD bus busy, clock set aborted\n");
733 		return;
734 	}
735 
736 	val = usdhi6_read(host, USDHI6_SD_CLK_CTRL) & ~USDHI6_SD_CLK_CTRL_DIV_MASK;
737 
738 	if (rate) {
739 		unsigned long new_rate;
740 
741 		if (host->imclk <= rate) {
742 			if (ios->timing != MMC_TIMING_UHS_DDR50) {
743 				/* Cannot have 1-to-1 clock in DDR mode */
744 				new_rate = host->imclk;
745 				val |= 0xff;
746 			} else {
747 				new_rate = host->imclk / 2;
748 			}
749 		} else {
750 			unsigned long div =
751 				roundup_pow_of_two(DIV_ROUND_UP(host->imclk, rate));
752 			val |= div >> 2;
753 			new_rate = host->imclk / div;
754 		}
755 
756 		if (host->rate == new_rate)
757 			return;
758 
759 		host->rate = new_rate;
760 
761 		dev_dbg(mmc_dev(host->mmc), "target %lu, div %u, set %lu\n",
762 			rate, (val & 0xff) << 2, new_rate);
763 	}
764 
765 	/*
766 	 * if old or new rate is equal to input rate, have to switch the clock
767 	 * off before changing and on after
768 	 */
769 	if (host->imclk == rate || host->imclk == host->rate || !rate)
770 		usdhi6_write(host, USDHI6_SD_CLK_CTRL,
771 			     val & ~USDHI6_SD_CLK_CTRL_SCLKEN);
772 
773 	if (!rate) {
774 		host->rate = 0;
775 		return;
776 	}
777 
778 	usdhi6_write(host, USDHI6_SD_CLK_CTRL, val);
779 
780 	if (host->imclk == rate || host->imclk == host->rate ||
781 	    !(val & USDHI6_SD_CLK_CTRL_SCLKEN))
782 		usdhi6_write(host, USDHI6_SD_CLK_CTRL,
783 			     val | USDHI6_SD_CLK_CTRL_SCLKEN);
784 }
785 
786 static void usdhi6_set_power(struct usdhi6_host *host, struct mmc_ios *ios)
787 {
788 	struct mmc_host *mmc = host->mmc;
789 
790 	if (!IS_ERR(mmc->supply.vmmc))
791 		/* Errors ignored... */
792 		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc,
793 				      ios->power_mode ? ios->vdd : 0);
794 }
795 
796 static int usdhi6_reset(struct usdhi6_host *host)
797 {
798 	int i;
799 
800 	usdhi6_write(host, USDHI6_SOFT_RST, USDHI6_SOFT_RST_RESERVED);
801 	cpu_relax();
802 	usdhi6_write(host, USDHI6_SOFT_RST, USDHI6_SOFT_RST_RESERVED | USDHI6_SOFT_RST_RESET);
803 	for (i = 1000; i; i--)
804 		if (usdhi6_read(host, USDHI6_SOFT_RST) & USDHI6_SOFT_RST_RESET)
805 			break;
806 
807 	return i ? 0 : -ETIMEDOUT;
808 }
809 
810 static void usdhi6_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
811 {
812 	struct usdhi6_host *host = mmc_priv(mmc);
813 	u32 option, mode;
814 	int ret;
815 
816 	dev_dbg(mmc_dev(mmc), "%uHz, OCR: %u, power %u, bus-width %u, timing %u\n",
817 		ios->clock, ios->vdd, ios->power_mode, ios->bus_width, ios->timing);
818 
819 	switch (ios->power_mode) {
820 	case MMC_POWER_OFF:
821 		usdhi6_set_power(host, ios);
822 		usdhi6_only_cd(host);
823 		break;
824 	case MMC_POWER_UP:
825 		/*
826 		 * We only also touch USDHI6_SD_OPTION from .request(), which
827 		 * cannot race with MMC_POWER_UP
828 		 */
829 		ret = usdhi6_reset(host);
830 		if (ret < 0) {
831 			dev_err(mmc_dev(mmc), "Cannot reset the interface!\n");
832 		} else {
833 			usdhi6_set_power(host, ios);
834 			usdhi6_only_cd(host);
835 		}
836 		break;
837 	case MMC_POWER_ON:
838 		option = usdhi6_read(host, USDHI6_SD_OPTION);
839 		/*
840 		 * The eMMC standard only allows 4 or 8 bits in the DDR mode,
841 		 * the same probably holds for SD cards. We check here anyway,
842 		 * since the datasheet explicitly requires 4 bits for DDR.
843 		 */
844 		if (ios->bus_width == MMC_BUS_WIDTH_1) {
845 			if (ios->timing == MMC_TIMING_UHS_DDR50)
846 				dev_err(mmc_dev(mmc),
847 					"4 bits are required for DDR\n");
848 			option |= USDHI6_SD_OPTION_WIDTH_1;
849 			mode = 0;
850 		} else {
851 			option &= ~USDHI6_SD_OPTION_WIDTH_1;
852 			mode = ios->timing == MMC_TIMING_UHS_DDR50;
853 		}
854 		usdhi6_write(host, USDHI6_SD_OPTION, option);
855 		usdhi6_write(host, USDHI6_SDIF_MODE, mode);
856 		break;
857 	}
858 
859 	if (host->rate != ios->clock)
860 		usdhi6_clk_set(host, ios);
861 }
862 
863 /* This is data timeout. Response timeout is fixed to 640 clock cycles */
864 static void usdhi6_timeout_set(struct usdhi6_host *host)
865 {
866 	struct mmc_request *mrq = host->mrq;
867 	u32 val;
868 	unsigned long ticks;
869 
870 	if (!mrq->data)
871 		ticks = host->rate / 1000 * mrq->cmd->busy_timeout;
872 	else
873 		ticks = host->rate / 1000000 * (mrq->data->timeout_ns / 1000) +
874 			mrq->data->timeout_clks;
875 
876 	if (!ticks || ticks > 1 << 27)
877 		/* Max timeout */
878 		val = 14;
879 	else if (ticks < 1 << 13)
880 		/* Min timeout */
881 		val = 0;
882 	else
883 		val = order_base_2(ticks) - 13;
884 
885 	dev_dbg(mmc_dev(host->mmc), "Set %s timeout %lu ticks @ %lu Hz\n",
886 		mrq->data ? "data" : "cmd", ticks, host->rate);
887 
888 	/* Timeout Counter mask: 0xf0 */
889 	usdhi6_write(host, USDHI6_SD_OPTION, (val << USDHI6_SD_OPTION_TIMEOUT_SHIFT) |
890 		     (usdhi6_read(host, USDHI6_SD_OPTION) & ~USDHI6_SD_OPTION_TIMEOUT_MASK));
891 }
892 
893 static void usdhi6_request_done(struct usdhi6_host *host)
894 {
895 	struct mmc_request *mrq = host->mrq;
896 	struct mmc_data *data = mrq->data;
897 
898 	if (WARN(host->pg.page || host->head_pg.page,
899 		 "Page %p or %p not unmapped: wait %u, CMD%d(%c) @ +0x%zx %ux%u in SG%u!\n",
900 		 host->pg.page, host->head_pg.page, host->wait, mrq->cmd->opcode,
901 		 data ? (data->flags & MMC_DATA_READ ? 'R' : 'W') : '-',
902 		 data ? host->offset : 0, data ? data->blocks : 0,
903 		 data ? data->blksz : 0, data ? data->sg_len : 0))
904 		usdhi6_sg_unmap(host, true);
905 
906 	if (mrq->cmd->error ||
907 	    (data && data->error) ||
908 	    (mrq->stop && mrq->stop->error))
909 		dev_dbg(mmc_dev(host->mmc), "%s(CMD%d: %ux%u): err %d %d %d\n",
910 			__func__, mrq->cmd->opcode, data ? data->blocks : 0,
911 			data ? data->blksz : 0,
912 			mrq->cmd->error,
913 			data ? data->error : 1,
914 			mrq->stop ? mrq->stop->error : 1);
915 
916 	/* Disable DMA */
917 	usdhi6_write(host, USDHI6_CC_EXT_MODE, 0);
918 	host->wait = USDHI6_WAIT_FOR_REQUEST;
919 	host->mrq = NULL;
920 
921 	mmc_request_done(host->mmc, mrq);
922 }
923 
924 static int usdhi6_cmd_flags(struct usdhi6_host *host)
925 {
926 	struct mmc_request *mrq = host->mrq;
927 	struct mmc_command *cmd = mrq->cmd;
928 	u16 opc = cmd->opcode;
929 
930 	if (host->app_cmd) {
931 		host->app_cmd = false;
932 		opc |= USDHI6_SD_CMD_APP;
933 	}
934 
935 	if (mrq->data) {
936 		opc |= USDHI6_SD_CMD_DATA;
937 
938 		if (mrq->data->flags & MMC_DATA_READ)
939 			opc |= USDHI6_SD_CMD_READ;
940 
941 		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
942 		    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
943 		    (cmd->opcode == SD_IO_RW_EXTENDED &&
944 		     mrq->data->blocks > 1)) {
945 			opc |= USDHI6_SD_CMD_MULTI;
946 			if (!mrq->stop)
947 				opc |= USDHI6_SD_CMD_CMD12_AUTO_OFF;
948 		}
949 
950 		switch (mmc_resp_type(cmd)) {
951 		case MMC_RSP_NONE:
952 			opc |= USDHI6_SD_CMD_MODE_RSP_NONE;
953 			break;
954 		case MMC_RSP_R1:
955 			opc |= USDHI6_SD_CMD_MODE_RSP_R1;
956 			break;
957 		case MMC_RSP_R1B:
958 			opc |= USDHI6_SD_CMD_MODE_RSP_R1B;
959 			break;
960 		case MMC_RSP_R2:
961 			opc |= USDHI6_SD_CMD_MODE_RSP_R2;
962 			break;
963 		case MMC_RSP_R3:
964 			opc |= USDHI6_SD_CMD_MODE_RSP_R3;
965 			break;
966 		default:
967 			dev_warn(mmc_dev(host->mmc),
968 				 "Unknown response type %d\n",
969 				 mmc_resp_type(cmd));
970 			return -EINVAL;
971 		}
972 	}
973 
974 	return opc;
975 }
976 
977 static int usdhi6_rq_start(struct usdhi6_host *host)
978 {
979 	struct mmc_request *mrq = host->mrq;
980 	struct mmc_command *cmd = mrq->cmd;
981 	struct mmc_data *data = mrq->data;
982 	int opc = usdhi6_cmd_flags(host);
983 	int i;
984 
985 	if (opc < 0)
986 		return opc;
987 
988 	for (i = 1000; i; i--) {
989 		if (!(usdhi6_read(host, USDHI6_SD_INFO2) & USDHI6_SD_INFO2_CBSY))
990 			break;
991 		usleep_range(10, 100);
992 	}
993 
994 	if (!i) {
995 		dev_dbg(mmc_dev(host->mmc), "Command active, request aborted\n");
996 		return -EAGAIN;
997 	}
998 
999 	if (data) {
1000 		bool use_dma;
1001 		int ret = 0;
1002 
1003 		host->page_idx = 0;
1004 
1005 		if (cmd->opcode == SD_IO_RW_EXTENDED && data->blocks > 1) {
1006 			switch (data->blksz) {
1007 			case 512:
1008 				break;
1009 			case 32:
1010 			case 64:
1011 			case 128:
1012 			case 256:
1013 				if (mrq->stop)
1014 					ret = -EINVAL;
1015 				break;
1016 			default:
1017 				ret = -EINVAL;
1018 			}
1019 		} else if ((cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1020 			    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK) &&
1021 			   data->blksz != 512) {
1022 			ret = -EINVAL;
1023 		}
1024 
1025 		if (ret < 0) {
1026 			dev_warn(mmc_dev(host->mmc), "%s(): %u blocks of %u bytes\n",
1027 				 __func__, data->blocks, data->blksz);
1028 			return -EINVAL;
1029 		}
1030 
1031 		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1032 		    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
1033 		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1034 		     data->blocks > 1))
1035 			usdhi6_sg_prep(host);
1036 
1037 		usdhi6_write(host, USDHI6_SD_SIZE, data->blksz);
1038 
1039 		if ((data->blksz >= USDHI6_MIN_DMA ||
1040 		     data->blocks > 1) &&
1041 		    (data->blksz % 4 ||
1042 		     data->sg->offset % 4))
1043 			dev_dbg(mmc_dev(host->mmc),
1044 				"Bad SG of %u: %ux%u @ %u\n", data->sg_len,
1045 				data->blksz, data->blocks, data->sg->offset);
1046 
1047 		/* Enable DMA for USDHI6_MIN_DMA bytes or more */
1048 		use_dma = data->blksz >= USDHI6_MIN_DMA &&
1049 			!(data->blksz % 4) &&
1050 			usdhi6_dma_start(host) >= DMA_MIN_COOKIE;
1051 
1052 		if (use_dma)
1053 			usdhi6_write(host, USDHI6_CC_EXT_MODE, USDHI6_CC_EXT_MODE_SDRW);
1054 
1055 		dev_dbg(mmc_dev(host->mmc),
1056 			"%s(): request opcode %u, %u blocks of %u bytes in %u segments, %s %s @+0x%x%s\n",
1057 			__func__, cmd->opcode, data->blocks, data->blksz,
1058 			data->sg_len, use_dma ? "DMA" : "PIO",
1059 			data->flags & MMC_DATA_READ ? "read" : "write",
1060 			data->sg->offset, mrq->stop ? " + stop" : "");
1061 	} else {
1062 		dev_dbg(mmc_dev(host->mmc), "%s(): request opcode %u\n",
1063 			__func__, cmd->opcode);
1064 	}
1065 
1066 	/* We have to get a command completion interrupt with DMA too */
1067 	usdhi6_wait_for_resp(host);
1068 
1069 	host->wait = USDHI6_WAIT_FOR_CMD;
1070 	schedule_delayed_work(&host->timeout_work, host->timeout);
1071 
1072 	/* SEC bit is required to enable block counting by the core */
1073 	usdhi6_write(host, USDHI6_SD_STOP,
1074 		     data && data->blocks > 1 ? USDHI6_SD_STOP_SEC : 0);
1075 	usdhi6_write(host, USDHI6_SD_ARG, cmd->arg);
1076 
1077 	/* Kick command execution */
1078 	usdhi6_write(host, USDHI6_SD_CMD, opc);
1079 
1080 	return 0;
1081 }
1082 
1083 static void usdhi6_request(struct mmc_host *mmc, struct mmc_request *mrq)
1084 {
1085 	struct usdhi6_host *host = mmc_priv(mmc);
1086 	int ret;
1087 
1088 	cancel_delayed_work_sync(&host->timeout_work);
1089 
1090 	host->mrq = mrq;
1091 	host->sg = NULL;
1092 
1093 	usdhi6_timeout_set(host);
1094 	ret = usdhi6_rq_start(host);
1095 	if (ret < 0) {
1096 		mrq->cmd->error = ret;
1097 		usdhi6_request_done(host);
1098 	}
1099 }
1100 
1101 static int usdhi6_get_cd(struct mmc_host *mmc)
1102 {
1103 	struct usdhi6_host *host = mmc_priv(mmc);
1104 	/* Read is atomic, no need to lock */
1105 	u32 status = usdhi6_read(host, USDHI6_SD_INFO1) & USDHI6_SD_INFO1_CD;
1106 
1107 /*
1108  *	level	status.CD	CD_ACTIVE_HIGH	card present
1109  *	1	0		0		0
1110  *	1	0		1		1
1111  *	0	1		0		1
1112  *	0	1		1		0
1113  */
1114 	return !status ^ !(mmc->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
1115 }
1116 
1117 static int usdhi6_get_ro(struct mmc_host *mmc)
1118 {
1119 	struct usdhi6_host *host = mmc_priv(mmc);
1120 	/* No locking as above */
1121 	u32 status = usdhi6_read(host, USDHI6_SD_INFO1) & USDHI6_SD_INFO1_WP;
1122 
1123 /*
1124  *	level	status.WP	RO_ACTIVE_HIGH	card read-only
1125  *	1	0		0		0
1126  *	1	0		1		1
1127  *	0	1		0		1
1128  *	0	1		1		0
1129  */
1130 	return !status ^ !(mmc->caps2 & MMC_CAP2_RO_ACTIVE_HIGH);
1131 }
1132 
1133 static void usdhi6_enable_sdio_irq(struct mmc_host *mmc, int enable)
1134 {
1135 	struct usdhi6_host *host = mmc_priv(mmc);
1136 
1137 	dev_dbg(mmc_dev(mmc), "%s(): %sable\n", __func__, enable ? "en" : "dis");
1138 
1139 	if (enable) {
1140 		host->sdio_mask = USDHI6_SDIO_INFO1_IRQ & ~USDHI6_SDIO_INFO1_IOIRQ;
1141 		usdhi6_write(host, USDHI6_SDIO_INFO1_MASK, host->sdio_mask);
1142 		usdhi6_write(host, USDHI6_SDIO_MODE, 1);
1143 	} else {
1144 		usdhi6_write(host, USDHI6_SDIO_MODE, 0);
1145 		usdhi6_write(host, USDHI6_SDIO_INFO1_MASK, USDHI6_SDIO_INFO1_IRQ);
1146 		host->sdio_mask = USDHI6_SDIO_INFO1_IRQ;
1147 	}
1148 }
1149 
1150 static struct mmc_host_ops usdhi6_ops = {
1151 	.request	= usdhi6_request,
1152 	.set_ios	= usdhi6_set_ios,
1153 	.get_cd		= usdhi6_get_cd,
1154 	.get_ro		= usdhi6_get_ro,
1155 	.enable_sdio_irq = usdhi6_enable_sdio_irq,
1156 };
1157 
1158 /*			State machine handlers				*/
1159 
1160 static void usdhi6_resp_cmd12(struct usdhi6_host *host)
1161 {
1162 	struct mmc_command *cmd = host->mrq->stop;
1163 	cmd->resp[0] = usdhi6_read(host, USDHI6_SD_RSP10);
1164 }
1165 
1166 static void usdhi6_resp_read(struct usdhi6_host *host)
1167 {
1168 	struct mmc_command *cmd = host->mrq->cmd;
1169 	u32 *rsp = cmd->resp, tmp = 0;
1170 	int i;
1171 
1172 /*
1173  * RSP10	39-8
1174  * RSP32	71-40
1175  * RSP54	103-72
1176  * RSP76	127-104
1177  * R2-type response:
1178  * resp[0]	= r[127..96]
1179  * resp[1]	= r[95..64]
1180  * resp[2]	= r[63..32]
1181  * resp[3]	= r[31..0]
1182  * Other responses:
1183  * resp[0]	= r[39..8]
1184  */
1185 
1186 	if (mmc_resp_type(cmd) == MMC_RSP_NONE)
1187 		return;
1188 
1189 	if (!(host->irq_status & USDHI6_SD_INFO1_RSP_END)) {
1190 		dev_err(mmc_dev(host->mmc),
1191 			"CMD%d: response expected but is missing!\n", cmd->opcode);
1192 		return;
1193 	}
1194 
1195 	if (mmc_resp_type(cmd) & MMC_RSP_136)
1196 		for (i = 0; i < 4; i++) {
1197 			if (i)
1198 				rsp[3 - i] = tmp >> 24;
1199 			tmp = usdhi6_read(host, USDHI6_SD_RSP10 + i * 8);
1200 			rsp[3 - i] |= tmp << 8;
1201 		}
1202 	else if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1203 		 cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK)
1204 		/* Read RSP54 to avoid conflict with auto CMD12 */
1205 		rsp[0] = usdhi6_read(host, USDHI6_SD_RSP54);
1206 	else
1207 		rsp[0] = usdhi6_read(host, USDHI6_SD_RSP10);
1208 
1209 	dev_dbg(mmc_dev(host->mmc), "Response 0x%x\n", rsp[0]);
1210 }
1211 
1212 static int usdhi6_blk_read(struct usdhi6_host *host)
1213 {
1214 	struct mmc_data *data = host->mrq->data;
1215 	u32 *p;
1216 	int i, rest;
1217 
1218 	if (host->io_error) {
1219 		data->error = usdhi6_error_code(host);
1220 		goto error;
1221 	}
1222 
1223 	if (host->pg.page) {
1224 		p = host->blk_page + host->offset;
1225 	} else {
1226 		p = usdhi6_sg_map(host);
1227 		if (!p) {
1228 			data->error = -ENOMEM;
1229 			goto error;
1230 		}
1231 	}
1232 
1233 	for (i = 0; i < data->blksz / 4; i++, p++)
1234 		*p = usdhi6_read(host, USDHI6_SD_BUF0);
1235 
1236 	rest = data->blksz % 4;
1237 	for (i = 0; i < (rest + 1) / 2; i++) {
1238 		u16 d = usdhi6_read16(host, USDHI6_SD_BUF0);
1239 		((u8 *)p)[2 * i] = ((u8 *)&d)[0];
1240 		if (rest > 1 && !i)
1241 			((u8 *)p)[2 * i + 1] = ((u8 *)&d)[1];
1242 	}
1243 
1244 	return 0;
1245 
1246 error:
1247 	dev_dbg(mmc_dev(host->mmc), "%s(): %d\n", __func__, data->error);
1248 	host->wait = USDHI6_WAIT_FOR_REQUEST;
1249 	return data->error;
1250 }
1251 
1252 static int usdhi6_blk_write(struct usdhi6_host *host)
1253 {
1254 	struct mmc_data *data = host->mrq->data;
1255 	u32 *p;
1256 	int i, rest;
1257 
1258 	if (host->io_error) {
1259 		data->error = usdhi6_error_code(host);
1260 		goto error;
1261 	}
1262 
1263 	if (host->pg.page) {
1264 		p = host->blk_page + host->offset;
1265 	} else {
1266 		p = usdhi6_sg_map(host);
1267 		if (!p) {
1268 			data->error = -ENOMEM;
1269 			goto error;
1270 		}
1271 	}
1272 
1273 	for (i = 0; i < data->blksz / 4; i++, p++)
1274 		usdhi6_write(host, USDHI6_SD_BUF0, *p);
1275 
1276 	rest = data->blksz % 4;
1277 	for (i = 0; i < (rest + 1) / 2; i++) {
1278 		u16 d;
1279 		((u8 *)&d)[0] = ((u8 *)p)[2 * i];
1280 		if (rest > 1 && !i)
1281 			((u8 *)&d)[1] = ((u8 *)p)[2 * i + 1];
1282 		else
1283 			((u8 *)&d)[1] = 0;
1284 		usdhi6_write16(host, USDHI6_SD_BUF0, d);
1285 	}
1286 
1287 	return 0;
1288 
1289 error:
1290 	dev_dbg(mmc_dev(host->mmc), "%s(): %d\n", __func__, data->error);
1291 	host->wait = USDHI6_WAIT_FOR_REQUEST;
1292 	return data->error;
1293 }
1294 
1295 static int usdhi6_stop_cmd(struct usdhi6_host *host)
1296 {
1297 	struct mmc_request *mrq = host->mrq;
1298 
1299 	switch (mrq->cmd->opcode) {
1300 	case MMC_READ_MULTIPLE_BLOCK:
1301 	case MMC_WRITE_MULTIPLE_BLOCK:
1302 		if (mrq->stop->opcode == MMC_STOP_TRANSMISSION) {
1303 			host->wait = USDHI6_WAIT_FOR_STOP;
1304 			return 0;
1305 		}
1306 		/* Unsupported STOP command */
1307 	default:
1308 		dev_err(mmc_dev(host->mmc),
1309 			"unsupported stop CMD%d for CMD%d\n",
1310 			mrq->stop->opcode, mrq->cmd->opcode);
1311 		mrq->stop->error = -EOPNOTSUPP;
1312 	}
1313 
1314 	return -EOPNOTSUPP;
1315 }
1316 
1317 static bool usdhi6_end_cmd(struct usdhi6_host *host)
1318 {
1319 	struct mmc_request *mrq = host->mrq;
1320 	struct mmc_command *cmd = mrq->cmd;
1321 
1322 	if (host->io_error) {
1323 		cmd->error = usdhi6_error_code(host);
1324 		return false;
1325 	}
1326 
1327 	usdhi6_resp_read(host);
1328 
1329 	if (!mrq->data)
1330 		return false;
1331 
1332 	if (host->dma_active) {
1333 		usdhi6_dma_kick(host);
1334 		if (!mrq->stop)
1335 			host->wait = USDHI6_WAIT_FOR_DMA;
1336 		else if (usdhi6_stop_cmd(host) < 0)
1337 			return false;
1338 	} else if (mrq->data->flags & MMC_DATA_READ) {
1339 		if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
1340 		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1341 		     mrq->data->blocks > 1))
1342 			host->wait = USDHI6_WAIT_FOR_MREAD;
1343 		else
1344 			host->wait = USDHI6_WAIT_FOR_READ;
1345 	} else {
1346 		if (cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK ||
1347 		    (cmd->opcode == SD_IO_RW_EXTENDED &&
1348 		     mrq->data->blocks > 1))
1349 			host->wait = USDHI6_WAIT_FOR_MWRITE;
1350 		else
1351 			host->wait = USDHI6_WAIT_FOR_WRITE;
1352 	}
1353 
1354 	return true;
1355 }
1356 
1357 static bool usdhi6_read_block(struct usdhi6_host *host)
1358 {
1359 	/* ACCESS_END IRQ is already unmasked */
1360 	int ret = usdhi6_blk_read(host);
1361 
1362 	/*
1363 	 * Have to force unmapping both pages: the single block could have been
1364 	 * cross-page, in which case for single-block IO host->page_idx == 0.
1365 	 * So, if we don't force, the second page won't be unmapped.
1366 	 */
1367 	usdhi6_sg_unmap(host, true);
1368 
1369 	if (ret < 0)
1370 		return false;
1371 
1372 	host->wait = USDHI6_WAIT_FOR_DATA_END;
1373 	return true;
1374 }
1375 
1376 static bool usdhi6_mread_block(struct usdhi6_host *host)
1377 {
1378 	int ret = usdhi6_blk_read(host);
1379 
1380 	if (ret < 0)
1381 		return false;
1382 
1383 	usdhi6_sg_advance(host);
1384 
1385 	return !host->mrq->data->error &&
1386 		(host->wait != USDHI6_WAIT_FOR_DATA_END || !host->mrq->stop);
1387 }
1388 
1389 static bool usdhi6_write_block(struct usdhi6_host *host)
1390 {
1391 	int ret = usdhi6_blk_write(host);
1392 
1393 	/* See comment in usdhi6_read_block() */
1394 	usdhi6_sg_unmap(host, true);
1395 
1396 	if (ret < 0)
1397 		return false;
1398 
1399 	host->wait = USDHI6_WAIT_FOR_DATA_END;
1400 	return true;
1401 }
1402 
1403 static bool usdhi6_mwrite_block(struct usdhi6_host *host)
1404 {
1405 	int ret = usdhi6_blk_write(host);
1406 
1407 	if (ret < 0)
1408 		return false;
1409 
1410 	usdhi6_sg_advance(host);
1411 
1412 	return !host->mrq->data->error &&
1413 		(host->wait != USDHI6_WAIT_FOR_DATA_END || !host->mrq->stop);
1414 }
1415 
1416 /*			Interrupt & timeout handlers			*/
1417 
1418 static irqreturn_t usdhi6_sd_bh(int irq, void *dev_id)
1419 {
1420 	struct usdhi6_host *host = dev_id;
1421 	struct mmc_request *mrq;
1422 	struct mmc_command *cmd;
1423 	struct mmc_data *data;
1424 	bool io_wait = false;
1425 
1426 	cancel_delayed_work_sync(&host->timeout_work);
1427 
1428 	mrq = host->mrq;
1429 	if (!mrq)
1430 		return IRQ_HANDLED;
1431 
1432 	cmd = mrq->cmd;
1433 	data = mrq->data;
1434 
1435 	switch (host->wait) {
1436 	case USDHI6_WAIT_FOR_REQUEST:
1437 		/* We're too late, the timeout has already kicked in */
1438 		return IRQ_HANDLED;
1439 	case USDHI6_WAIT_FOR_CMD:
1440 		/* Wait for data? */
1441 		io_wait = usdhi6_end_cmd(host);
1442 		break;
1443 	case USDHI6_WAIT_FOR_MREAD:
1444 		/* Wait for more data? */
1445 		io_wait = usdhi6_mread_block(host);
1446 		break;
1447 	case USDHI6_WAIT_FOR_READ:
1448 		/* Wait for data end? */
1449 		io_wait = usdhi6_read_block(host);
1450 		break;
1451 	case USDHI6_WAIT_FOR_MWRITE:
1452 		/* Wait data to write? */
1453 		io_wait = usdhi6_mwrite_block(host);
1454 		break;
1455 	case USDHI6_WAIT_FOR_WRITE:
1456 		/* Wait for data end? */
1457 		io_wait = usdhi6_write_block(host);
1458 		break;
1459 	case USDHI6_WAIT_FOR_DMA:
1460 		usdhi6_dma_check_error(host);
1461 		break;
1462 	case USDHI6_WAIT_FOR_STOP:
1463 		usdhi6_write(host, USDHI6_SD_STOP, 0);
1464 		if (host->io_error) {
1465 			int ret = usdhi6_error_code(host);
1466 			if (mrq->stop)
1467 				mrq->stop->error = ret;
1468 			else
1469 				mrq->data->error = ret;
1470 			dev_warn(mmc_dev(host->mmc), "%s(): %d\n", __func__, ret);
1471 			break;
1472 		}
1473 		usdhi6_resp_cmd12(host);
1474 		mrq->stop->error = 0;
1475 		break;
1476 	case USDHI6_WAIT_FOR_DATA_END:
1477 		if (host->io_error) {
1478 			mrq->data->error = usdhi6_error_code(host);
1479 			dev_warn(mmc_dev(host->mmc), "%s(): %d\n", __func__,
1480 				 mrq->data->error);
1481 		}
1482 		break;
1483 	default:
1484 		cmd->error = -EFAULT;
1485 		dev_err(mmc_dev(host->mmc), "Invalid state %u\n", host->wait);
1486 		usdhi6_request_done(host);
1487 		return IRQ_HANDLED;
1488 	}
1489 
1490 	if (io_wait) {
1491 		schedule_delayed_work(&host->timeout_work, host->timeout);
1492 		/* Wait for more data or ACCESS_END */
1493 		if (!host->dma_active)
1494 			usdhi6_wait_for_brwe(host, mrq->data->flags & MMC_DATA_READ);
1495 		return IRQ_HANDLED;
1496 	}
1497 
1498 	if (!cmd->error) {
1499 		if (data) {
1500 			if (!data->error) {
1501 				if (host->wait != USDHI6_WAIT_FOR_STOP &&
1502 				    host->mrq->stop &&
1503 				    !host->mrq->stop->error &&
1504 				    !usdhi6_stop_cmd(host)) {
1505 					/* Sending STOP */
1506 					usdhi6_wait_for_resp(host);
1507 
1508 					schedule_delayed_work(&host->timeout_work,
1509 							      host->timeout);
1510 
1511 					return IRQ_HANDLED;
1512 				}
1513 
1514 				data->bytes_xfered = data->blocks * data->blksz;
1515 			} else {
1516 				/* Data error: might need to unmap the last page */
1517 				dev_warn(mmc_dev(host->mmc), "%s(): data error %d\n",
1518 					 __func__, data->error);
1519 				usdhi6_sg_unmap(host, true);
1520 			}
1521 		} else if (cmd->opcode == MMC_APP_CMD) {
1522 			host->app_cmd = true;
1523 		}
1524 	}
1525 
1526 	usdhi6_request_done(host);
1527 
1528 	return IRQ_HANDLED;
1529 }
1530 
1531 static irqreturn_t usdhi6_sd(int irq, void *dev_id)
1532 {
1533 	struct usdhi6_host *host = dev_id;
1534 	u16 status, status2, error;
1535 
1536 	status = usdhi6_read(host, USDHI6_SD_INFO1) & ~host->status_mask &
1537 		~USDHI6_SD_INFO1_CARD;
1538 	status2 = usdhi6_read(host, USDHI6_SD_INFO2) & ~host->status2_mask;
1539 
1540 	usdhi6_only_cd(host);
1541 
1542 	dev_dbg(mmc_dev(host->mmc),
1543 		"IRQ status = 0x%08x, status2 = 0x%08x\n", status, status2);
1544 
1545 	if (!status && !status2)
1546 		return IRQ_NONE;
1547 
1548 	error = status2 & USDHI6_SD_INFO2_ERR;
1549 
1550 	/* Ack / clear interrupts */
1551 	if (USDHI6_SD_INFO1_IRQ & status)
1552 		usdhi6_write(host, USDHI6_SD_INFO1,
1553 			     0xffff & ~(USDHI6_SD_INFO1_IRQ & status));
1554 
1555 	if (USDHI6_SD_INFO2_IRQ & status2) {
1556 		if (error)
1557 			/* In error cases BWE and BRE aren't cleared automatically */
1558 			status2 |= USDHI6_SD_INFO2_BWE | USDHI6_SD_INFO2_BRE;
1559 
1560 		usdhi6_write(host, USDHI6_SD_INFO2,
1561 			     0xffff & ~(USDHI6_SD_INFO2_IRQ & status2));
1562 	}
1563 
1564 	host->io_error = error;
1565 	host->irq_status = status;
1566 
1567 	if (error) {
1568 		/* Don't pollute the log with unsupported command timeouts */
1569 		if (host->wait != USDHI6_WAIT_FOR_CMD ||
1570 		    error != USDHI6_SD_INFO2_RSP_TOUT)
1571 			dev_warn(mmc_dev(host->mmc),
1572 				 "%s(): INFO2 error bits 0x%08x\n",
1573 				 __func__, error);
1574 		else
1575 			dev_dbg(mmc_dev(host->mmc),
1576 				"%s(): INFO2 error bits 0x%08x\n",
1577 				__func__, error);
1578 	}
1579 
1580 	return IRQ_WAKE_THREAD;
1581 }
1582 
1583 static irqreturn_t usdhi6_sdio(int irq, void *dev_id)
1584 {
1585 	struct usdhi6_host *host = dev_id;
1586 	u32 status = usdhi6_read(host, USDHI6_SDIO_INFO1) & ~host->sdio_mask;
1587 
1588 	dev_dbg(mmc_dev(host->mmc), "%s(): status 0x%x\n", __func__, status);
1589 
1590 	if (!status)
1591 		return IRQ_NONE;
1592 
1593 	usdhi6_write(host, USDHI6_SDIO_INFO1, ~status);
1594 
1595 	mmc_signal_sdio_irq(host->mmc);
1596 
1597 	return IRQ_HANDLED;
1598 }
1599 
1600 static irqreturn_t usdhi6_cd(int irq, void *dev_id)
1601 {
1602 	struct usdhi6_host *host = dev_id;
1603 	struct mmc_host *mmc = host->mmc;
1604 	u16 status;
1605 
1606 	/* We're only interested in hotplug events here */
1607 	status = usdhi6_read(host, USDHI6_SD_INFO1) & ~host->status_mask &
1608 		USDHI6_SD_INFO1_CARD;
1609 
1610 	if (!status)
1611 		return IRQ_NONE;
1612 
1613 	/* Ack */
1614 	usdhi6_write(host, USDHI6_SD_INFO1, ~status);
1615 
1616 	if (!work_pending(&mmc->detect.work) &&
1617 	    (((status & USDHI6_SD_INFO1_CARD_INSERT) &&
1618 	      !mmc->card) ||
1619 	     ((status & USDHI6_SD_INFO1_CARD_EJECT) &&
1620 	      mmc->card)))
1621 		mmc_detect_change(mmc, msecs_to_jiffies(100));
1622 
1623 	return IRQ_HANDLED;
1624 }
1625 
1626 /*
1627  * Actually this should not be needed, if the built-in timeout works reliably in
1628  * the both PIO cases and DMA never fails. But if DMA does fail, a timeout
1629  * handler might be the only way to catch the error.
1630  */
1631 static void usdhi6_timeout_work(struct work_struct *work)
1632 {
1633 	struct delayed_work *d = container_of(work, struct delayed_work, work);
1634 	struct usdhi6_host *host = container_of(d, struct usdhi6_host, timeout_work);
1635 	struct mmc_request *mrq = host->mrq;
1636 	struct mmc_data *data = mrq ? mrq->data : NULL;
1637 	struct scatterlist *sg;
1638 
1639 	dev_warn(mmc_dev(host->mmc),
1640 		 "%s timeout wait %u CMD%d: IRQ 0x%08x:0x%08x, last IRQ 0x%08x\n",
1641 		 host->dma_active ? "DMA" : "PIO",
1642 		 host->wait, mrq ? mrq->cmd->opcode : -1,
1643 		 usdhi6_read(host, USDHI6_SD_INFO1),
1644 		 usdhi6_read(host, USDHI6_SD_INFO2), host->irq_status);
1645 
1646 	if (host->dma_active) {
1647 		usdhi6_dma_kill(host);
1648 		usdhi6_dma_stop_unmap(host);
1649 	}
1650 
1651 	switch (host->wait) {
1652 	default:
1653 		dev_err(mmc_dev(host->mmc), "Invalid state %u\n", host->wait);
1654 		/* mrq can be NULL in this actually impossible case */
1655 	case USDHI6_WAIT_FOR_CMD:
1656 		usdhi6_error_code(host);
1657 		if (mrq)
1658 			mrq->cmd->error = -ETIMEDOUT;
1659 		break;
1660 	case USDHI6_WAIT_FOR_STOP:
1661 		usdhi6_error_code(host);
1662 		mrq->stop->error = -ETIMEDOUT;
1663 		break;
1664 	case USDHI6_WAIT_FOR_DMA:
1665 	case USDHI6_WAIT_FOR_MREAD:
1666 	case USDHI6_WAIT_FOR_MWRITE:
1667 	case USDHI6_WAIT_FOR_READ:
1668 	case USDHI6_WAIT_FOR_WRITE:
1669 		sg = host->sg ?: data->sg;
1670 		dev_dbg(mmc_dev(host->mmc),
1671 			"%c: page #%u @ +0x%zx %ux%u in SG%u. Current SG %u bytes @ %u\n",
1672 			data->flags & MMC_DATA_READ ? 'R' : 'W', host->page_idx,
1673 			host->offset, data->blocks, data->blksz, data->sg_len,
1674 			sg_dma_len(sg), sg->offset);
1675 		usdhi6_sg_unmap(host, true);
1676 		/*
1677 		 * If USDHI6_WAIT_FOR_DATA_END times out, we have already unmapped
1678 		 * the page
1679 		 */
1680 	case USDHI6_WAIT_FOR_DATA_END:
1681 		usdhi6_error_code(host);
1682 		data->error = -ETIMEDOUT;
1683 	}
1684 
1685 	if (mrq)
1686 		usdhi6_request_done(host);
1687 }
1688 
1689 /*			 Probe / release				*/
1690 
1691 static const struct of_device_id usdhi6_of_match[] = {
1692 	{.compatible = "renesas,usdhi6rol0"},
1693 	{}
1694 };
1695 MODULE_DEVICE_TABLE(of, usdhi6_of_match);
1696 
1697 static int usdhi6_probe(struct platform_device *pdev)
1698 {
1699 	struct device *dev = &pdev->dev;
1700 	struct mmc_host *mmc;
1701 	struct usdhi6_host *host;
1702 	struct resource *res;
1703 	int irq_cd, irq_sd, irq_sdio;
1704 	u32 version;
1705 	int ret;
1706 
1707 	if (!dev->of_node)
1708 		return -ENODEV;
1709 
1710 	irq_cd = platform_get_irq_byname(pdev, "card detect");
1711 	irq_sd = platform_get_irq_byname(pdev, "data");
1712 	irq_sdio = platform_get_irq_byname(pdev, "SDIO");
1713 	if (irq_sd < 0 || irq_sdio < 0)
1714 		return -ENODEV;
1715 
1716 	mmc = mmc_alloc_host(sizeof(struct usdhi6_host), dev);
1717 	if (!mmc)
1718 		return -ENOMEM;
1719 
1720 	ret = mmc_regulator_get_supply(mmc);
1721 	if (ret == -EPROBE_DEFER)
1722 		goto e_free_mmc;
1723 
1724 	ret = mmc_of_parse(mmc);
1725 	if (ret < 0)
1726 		goto e_free_mmc;
1727 
1728 	host		= mmc_priv(mmc);
1729 	host->mmc	= mmc;
1730 	host->wait	= USDHI6_WAIT_FOR_REQUEST;
1731 	host->timeout	= msecs_to_jiffies(4000);
1732 
1733 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1734 	host->base = devm_ioremap_resource(dev, res);
1735 	if (IS_ERR(host->base)) {
1736 		ret = PTR_ERR(host->base);
1737 		goto e_free_mmc;
1738 	}
1739 
1740 	host->clk = devm_clk_get(dev, NULL);
1741 	if (IS_ERR(host->clk)) {
1742 		ret = PTR_ERR(host->clk);
1743 		goto e_free_mmc;
1744 	}
1745 
1746 	host->imclk = clk_get_rate(host->clk);
1747 
1748 	ret = clk_prepare_enable(host->clk);
1749 	if (ret < 0)
1750 		goto e_free_mmc;
1751 
1752 	version = usdhi6_read(host, USDHI6_VERSION);
1753 	if ((version & 0xfff) != 0xa0d) {
1754 		dev_err(dev, "Version not recognized %x\n", version);
1755 		goto e_clk_off;
1756 	}
1757 
1758 	dev_info(dev, "A USDHI6ROL0 SD host detected with %d ports\n",
1759 		 usdhi6_read(host, USDHI6_SD_PORT_SEL) >> USDHI6_SD_PORT_SEL_PORTS_SHIFT);
1760 
1761 	usdhi6_mask_all(host);
1762 
1763 	if (irq_cd >= 0) {
1764 		ret = devm_request_irq(dev, irq_cd, usdhi6_cd, 0,
1765 				       dev_name(dev), host);
1766 		if (ret < 0)
1767 			goto e_clk_off;
1768 	} else {
1769 		mmc->caps |= MMC_CAP_NEEDS_POLL;
1770 	}
1771 
1772 	ret = devm_request_threaded_irq(dev, irq_sd, usdhi6_sd, usdhi6_sd_bh, 0,
1773 			       dev_name(dev), host);
1774 	if (ret < 0)
1775 		goto e_clk_off;
1776 
1777 	ret = devm_request_irq(dev, irq_sdio, usdhi6_sdio, 0,
1778 			       dev_name(dev), host);
1779 	if (ret < 0)
1780 		goto e_clk_off;
1781 
1782 	INIT_DELAYED_WORK(&host->timeout_work, usdhi6_timeout_work);
1783 
1784 	usdhi6_dma_request(host, res->start);
1785 
1786 	mmc->ops = &usdhi6_ops;
1787 	mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
1788 		MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_DDR50 | MMC_CAP_SDIO_IRQ;
1789 	/* Set .max_segs to some random number. Feel free to adjust. */
1790 	mmc->max_segs = 32;
1791 	mmc->max_blk_size = 512;
1792 	mmc->max_req_size = PAGE_CACHE_SIZE * mmc->max_segs;
1793 	mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
1794 	/*
1795 	 * Setting .max_seg_size to 1 page would simplify our page-mapping code,
1796 	 * But OTOH, having large segments makes DMA more efficient. We could
1797 	 * check, whether we managed to get DMA and fall back to 1 page
1798 	 * segments, but if we do manage to obtain DMA and then it fails at
1799 	 * run-time and we fall back to PIO, we will continue getting large
1800 	 * segments. So, we wouldn't be able to get rid of the code anyway.
1801 	 */
1802 	mmc->max_seg_size = mmc->max_req_size;
1803 	if (!mmc->f_max)
1804 		mmc->f_max = host->imclk;
1805 	mmc->f_min = host->imclk / 512;
1806 
1807 	platform_set_drvdata(pdev, host);
1808 
1809 	ret = mmc_add_host(mmc);
1810 	if (ret < 0)
1811 		goto e_clk_off;
1812 
1813 	return 0;
1814 
1815 e_clk_off:
1816 	clk_disable_unprepare(host->clk);
1817 e_free_mmc:
1818 	mmc_free_host(mmc);
1819 
1820 	return ret;
1821 }
1822 
1823 static int usdhi6_remove(struct platform_device *pdev)
1824 {
1825 	struct usdhi6_host *host = platform_get_drvdata(pdev);
1826 
1827 	mmc_remove_host(host->mmc);
1828 
1829 	usdhi6_mask_all(host);
1830 	cancel_delayed_work_sync(&host->timeout_work);
1831 	usdhi6_dma_release(host);
1832 	clk_disable_unprepare(host->clk);
1833 	mmc_free_host(host->mmc);
1834 
1835 	return 0;
1836 }
1837 
1838 static struct platform_driver usdhi6_driver = {
1839 	.probe		= usdhi6_probe,
1840 	.remove		= usdhi6_remove,
1841 	.driver		= {
1842 		.name	= "usdhi6rol0",
1843 		.of_match_table = usdhi6_of_match,
1844 	},
1845 };
1846 
1847 module_platform_driver(usdhi6_driver);
1848 
1849 MODULE_DESCRIPTION("Renesas usdhi6rol0 SD/SDIO host driver");
1850 MODULE_LICENSE("GPL v2");
1851 MODULE_ALIAS("platform:usdhi6rol0");
1852 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
1853