Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / mmc / host / usdhi6rol0.c
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
1638         dev_warn(mmc_dev(host->mmc),
1639                  "%s timeout wait %u CMD%d: IRQ 0x%08x:0x%08x, last IRQ 0x%08x\n",
1640                  host->dma_active ? "DMA" : "PIO",
1641                  host->wait, mrq ? mrq->cmd->opcode : -1,
1642                  usdhi6_read(host, USDHI6_SD_INFO1),
1643                  usdhi6_read(host, USDHI6_SD_INFO2), host->irq_status);
1644
1645         if (host->dma_active) {
1646                 usdhi6_dma_kill(host);
1647                 usdhi6_dma_stop_unmap(host);
1648         }
1649
1650         switch (host->wait) {
1651         default:
1652                 dev_err(mmc_dev(host->mmc), "Invalid state %u\n", host->wait);
1653                 /* mrq can be NULL in this actually impossible case */
1654         case USDHI6_WAIT_FOR_CMD:
1655                 usdhi6_error_code(host);
1656                 if (mrq)
1657                         mrq->cmd->error = -ETIMEDOUT;
1658                 break;
1659         case USDHI6_WAIT_FOR_STOP:
1660                 usdhi6_error_code(host);
1661                 mrq->stop->error = -ETIMEDOUT;
1662                 break;
1663         case USDHI6_WAIT_FOR_DMA:
1664         case USDHI6_WAIT_FOR_MREAD:
1665         case USDHI6_WAIT_FOR_MWRITE:
1666         case USDHI6_WAIT_FOR_READ:
1667         case USDHI6_WAIT_FOR_WRITE:
1668                 dev_dbg(mmc_dev(host->mmc),
1669                         "%c: page #%u @ +0x%zx %ux%u in SG%u. Current SG %u bytes @ %u\n",
1670                         data->flags & MMC_DATA_READ ? 'R' : 'W', host->page_idx,
1671                         host->offset, data->blocks, data->blksz, data->sg_len,
1672                         sg_dma_len(host->sg), host->sg->offset);
1673                 usdhi6_sg_unmap(host, true);
1674                 /*
1675                  * If USDHI6_WAIT_FOR_DATA_END times out, we have already unmapped
1676                  * the page
1677                  */
1678         case USDHI6_WAIT_FOR_DATA_END:
1679                 usdhi6_error_code(host);
1680                 data->error = -ETIMEDOUT;
1681         }
1682
1683         if (mrq)
1684                 usdhi6_request_done(host);
1685 }
1686
1687 /*                       Probe / release                                */
1688
1689 static const struct of_device_id usdhi6_of_match[] = {
1690         {.compatible = "renesas,usdhi6rol0"},
1691         {}
1692 };
1693 MODULE_DEVICE_TABLE(of, usdhi6_of_match);
1694
1695 static int usdhi6_probe(struct platform_device *pdev)
1696 {
1697         struct device *dev = &pdev->dev;
1698         struct mmc_host *mmc;
1699         struct usdhi6_host *host;
1700         struct resource *res;
1701         int irq_cd, irq_sd, irq_sdio;
1702         u32 version;
1703         int ret;
1704
1705         if (!dev->of_node)
1706                 return -ENODEV;
1707
1708         irq_cd = platform_get_irq_byname(pdev, "card detect");
1709         irq_sd = platform_get_irq_byname(pdev, "data");
1710         irq_sdio = platform_get_irq_byname(pdev, "SDIO");
1711         if (irq_sd < 0 || irq_sdio < 0)
1712                 return -ENODEV;
1713
1714         mmc = mmc_alloc_host(sizeof(struct usdhi6_host), dev);
1715         if (!mmc)
1716                 return -ENOMEM;
1717
1718         ret = mmc_of_parse(mmc);
1719         if (ret < 0)
1720                 goto e_free_mmc;
1721
1722         mmc_regulator_get_supply(mmc);
1723
1724         host            = mmc_priv(mmc);
1725         host->mmc       = mmc;
1726         host->wait      = USDHI6_WAIT_FOR_REQUEST;
1727         host->timeout   = msecs_to_jiffies(4000);
1728
1729         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1730         host->base = devm_ioremap_resource(dev, res);
1731         if (IS_ERR(host->base)) {
1732                 ret = PTR_ERR(host->base);
1733                 goto e_free_mmc;
1734         }
1735
1736         host->clk = devm_clk_get(dev, NULL);
1737         if (IS_ERR(host->clk))
1738                 goto e_free_mmc;
1739
1740         host->imclk = clk_get_rate(host->clk);
1741
1742         ret = clk_prepare_enable(host->clk);
1743         if (ret < 0)
1744                 goto e_free_mmc;
1745
1746         version = usdhi6_read(host, USDHI6_VERSION);
1747         if ((version & 0xfff) != 0xa0d) {
1748                 dev_err(dev, "Version not recognized %x\n", version);
1749                 goto e_clk_off;
1750         }
1751
1752         dev_info(dev, "A USDHI6ROL0 SD host detected with %d ports\n",
1753                  usdhi6_read(host, USDHI6_SD_PORT_SEL) >> USDHI6_SD_PORT_SEL_PORTS_SHIFT);
1754
1755         usdhi6_mask_all(host);
1756
1757         if (irq_cd >= 0) {
1758                 ret = devm_request_irq(dev, irq_cd, usdhi6_cd, 0,
1759                                        dev_name(dev), host);
1760                 if (ret < 0)
1761                         goto e_clk_off;
1762         } else {
1763                 mmc->caps |= MMC_CAP_NEEDS_POLL;
1764         }
1765
1766         ret = devm_request_threaded_irq(dev, irq_sd, usdhi6_sd, usdhi6_sd_bh, 0,
1767                                dev_name(dev), host);
1768         if (ret < 0)
1769                 goto e_clk_off;
1770
1771         ret = devm_request_irq(dev, irq_sdio, usdhi6_sdio, 0,
1772                                dev_name(dev), host);
1773         if (ret < 0)
1774                 goto e_clk_off;
1775
1776         INIT_DELAYED_WORK(&host->timeout_work, usdhi6_timeout_work);
1777
1778         usdhi6_dma_request(host, res->start);
1779
1780         mmc->ops = &usdhi6_ops;
1781         mmc->caps |= MMC_CAP_SD_HIGHSPEED | MMC_CAP_MMC_HIGHSPEED |
1782                 MMC_CAP_UHS_SDR50 | MMC_CAP_UHS_DDR50 | MMC_CAP_SDIO_IRQ;
1783         /* Set .max_segs to some random number. Feel free to adjust. */
1784         mmc->max_segs = 32;
1785         mmc->max_blk_size = 512;
1786         mmc->max_req_size = PAGE_CACHE_SIZE * mmc->max_segs;
1787         mmc->max_blk_count = mmc->max_req_size / mmc->max_blk_size;
1788         /*
1789          * Setting .max_seg_size to 1 page would simplify our page-mapping code,
1790          * But OTOH, having large segments makes DMA more efficient. We could
1791          * check, whether we managed to get DMA and fall back to 1 page
1792          * segments, but if we do manage to obtain DMA and then it fails at
1793          * run-time and we fall back to PIO, we will continue getting large
1794          * segments. So, we wouldn't be able to get rid of the code anyway.
1795          */
1796         mmc->max_seg_size = mmc->max_req_size;
1797         if (!mmc->f_max)
1798                 mmc->f_max = host->imclk;
1799         mmc->f_min = host->imclk / 512;
1800
1801         platform_set_drvdata(pdev, host);
1802
1803         ret = mmc_add_host(mmc);
1804         if (ret < 0)
1805                 goto e_clk_off;
1806
1807         return 0;
1808
1809 e_clk_off:
1810         clk_disable_unprepare(host->clk);
1811 e_free_mmc:
1812         mmc_free_host(mmc);
1813
1814         return ret;
1815 }
1816
1817 static int usdhi6_remove(struct platform_device *pdev)
1818 {
1819         struct usdhi6_host *host = platform_get_drvdata(pdev);
1820
1821         mmc_remove_host(host->mmc);
1822
1823         usdhi6_mask_all(host);
1824         cancel_delayed_work_sync(&host->timeout_work);
1825         usdhi6_dma_release(host);
1826         clk_disable_unprepare(host->clk);
1827         mmc_free_host(host->mmc);
1828
1829         return 0;
1830 }
1831
1832 static struct platform_driver usdhi6_driver = {
1833         .probe          = usdhi6_probe,
1834         .remove         = usdhi6_remove,
1835         .driver         = {
1836                 .name   = "usdhi6rol0",
1837                 .of_match_table = usdhi6_of_match,
1838         },
1839 };
1840
1841 module_platform_driver(usdhi6_driver);
1842
1843 MODULE_DESCRIPTION("Renesas usdhi6rol0 SD/SDIO host driver");
1844 MODULE_LICENSE("GPL v2");
1845 MODULE_ALIAS("platform:usdhi6rol0");
1846 MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");