xref: /linux/drivers/mmc/host/wmt-sdmmc.c (revision 307797159ac25fe5a2048bf5c6a5718298edca57)
1 /*
2  *  WM8505/WM8650 SD/MMC Host Controller
3  *
4  *  Copyright (C) 2010 Tony Prisk
5  *  Copyright (C) 2008 WonderMedia Technologies, Inc.
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License version 2 as
9  *  published by the Free Software Foundation
10  */
11 
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/ioport.h>
16 #include <linux/errno.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/delay.h>
19 #include <linux/io.h>
20 #include <linux/irq.h>
21 #include <linux/clk.h>
22 #include <linux/gpio.h>
23 #include <linux/interrupt.h>
24 
25 #include <linux/of.h>
26 #include <linux/of_address.h>
27 #include <linux/of_irq.h>
28 #include <linux/of_device.h>
29 
30 #include <linux/mmc/host.h>
31 #include <linux/mmc/mmc.h>
32 #include <linux/mmc/sd.h>
33 
34 #include <asm/byteorder.h>
35 
36 
37 #define DRIVER_NAME "wmt-sdhc"
38 
39 
40 /* MMC/SD controller registers */
41 #define SDMMC_CTLR			0x00
42 #define SDMMC_CMD			0x01
43 #define SDMMC_RSPTYPE			0x02
44 #define SDMMC_ARG			0x04
45 #define SDMMC_BUSMODE			0x08
46 #define SDMMC_BLKLEN			0x0C
47 #define SDMMC_BLKCNT			0x0E
48 #define SDMMC_RSP			0x10
49 #define SDMMC_CBCR			0x20
50 #define SDMMC_INTMASK0			0x24
51 #define SDMMC_INTMASK1			0x25
52 #define SDMMC_STS0			0x28
53 #define SDMMC_STS1			0x29
54 #define SDMMC_STS2			0x2A
55 #define SDMMC_STS3			0x2B
56 #define SDMMC_RSPTIMEOUT		0x2C
57 #define SDMMC_CLK			0x30	/* VT8500 only */
58 #define SDMMC_EXTCTRL			0x34
59 #define SDMMC_SBLKLEN			0x38
60 #define SDMMC_DMATIMEOUT		0x3C
61 
62 
63 /* SDMMC_CTLR bit fields */
64 #define CTLR_CMD_START			0x01
65 #define CTLR_CMD_WRITE			0x04
66 #define CTLR_FIFO_RESET			0x08
67 
68 /* SDMMC_BUSMODE bit fields */
69 #define BM_SPI_MODE			0x01
70 #define BM_FOURBIT_MODE			0x02
71 #define BM_EIGHTBIT_MODE		0x04
72 #define BM_SD_OFF			0x10
73 #define BM_SPI_CS			0x20
74 #define BM_SD_POWER			0x40
75 #define BM_SOFT_RESET			0x80
76 
77 /* SDMMC_BLKLEN bit fields */
78 #define BLKL_CRCERR_ABORT		0x0800
79 #define BLKL_CD_POL_HIGH		0x1000
80 #define BLKL_GPI_CD			0x2000
81 #define BLKL_DATA3_CD			0x4000
82 #define BLKL_INT_ENABLE			0x8000
83 
84 /* SDMMC_INTMASK0 bit fields */
85 #define INT0_MBLK_TRAN_DONE_INT_EN	0x10
86 #define INT0_BLK_TRAN_DONE_INT_EN	0x20
87 #define INT0_CD_INT_EN			0x40
88 #define INT0_DI_INT_EN			0x80
89 
90 /* SDMMC_INTMASK1 bit fields */
91 #define INT1_CMD_RES_TRAN_DONE_INT_EN	0x02
92 #define INT1_CMD_RES_TOUT_INT_EN	0x04
93 #define INT1_MBLK_AUTO_STOP_INT_EN	0x08
94 #define INT1_DATA_TOUT_INT_EN		0x10
95 #define INT1_RESCRC_ERR_INT_EN		0x20
96 #define INT1_RCRC_ERR_INT_EN		0x40
97 #define INT1_WCRC_ERR_INT_EN		0x80
98 
99 /* SDMMC_STS0 bit fields */
100 #define STS0_WRITE_PROTECT		0x02
101 #define STS0_CD_DATA3			0x04
102 #define STS0_CD_GPI			0x08
103 #define STS0_MBLK_DONE			0x10
104 #define STS0_BLK_DONE			0x20
105 #define STS0_CARD_DETECT		0x40
106 #define STS0_DEVICE_INS			0x80
107 
108 /* SDMMC_STS1 bit fields */
109 #define STS1_SDIO_INT			0x01
110 #define STS1_CMDRSP_DONE		0x02
111 #define STS1_RSP_TIMEOUT		0x04
112 #define STS1_AUTOSTOP_DONE		0x08
113 #define STS1_DATA_TIMEOUT		0x10
114 #define STS1_RSP_CRC_ERR		0x20
115 #define STS1_RCRC_ERR			0x40
116 #define STS1_WCRC_ERR			0x80
117 
118 /* SDMMC_STS2 bit fields */
119 #define STS2_CMD_RES_BUSY		0x10
120 #define STS2_DATARSP_BUSY		0x20
121 #define STS2_DIS_FORCECLK		0x80
122 
123 /* SDMMC_EXTCTRL bit fields */
124 #define EXT_EIGHTBIT			0x04
125 
126 /* MMC/SD DMA Controller Registers */
127 #define SDDMA_GCR			0x100
128 #define SDDMA_IER			0x104
129 #define SDDMA_ISR			0x108
130 #define SDDMA_DESPR			0x10C
131 #define SDDMA_RBR			0x110
132 #define SDDMA_DAR			0x114
133 #define SDDMA_BAR			0x118
134 #define SDDMA_CPR			0x11C
135 #define SDDMA_CCR			0x120
136 
137 
138 /* SDDMA_GCR bit fields */
139 #define DMA_GCR_DMA_EN			0x00000001
140 #define DMA_GCR_SOFT_RESET		0x00000100
141 
142 /* SDDMA_IER bit fields */
143 #define DMA_IER_INT_EN			0x00000001
144 
145 /* SDDMA_ISR bit fields */
146 #define DMA_ISR_INT_STS			0x00000001
147 
148 /* SDDMA_RBR bit fields */
149 #define DMA_RBR_FORMAT			0x40000000
150 #define DMA_RBR_END			0x80000000
151 
152 /* SDDMA_CCR bit fields */
153 #define DMA_CCR_RUN			0x00000080
154 #define DMA_CCR_IF_TO_PERIPHERAL	0x00000000
155 #define DMA_CCR_PERIPHERAL_TO_IF	0x00400000
156 
157 /* SDDMA_CCR event status */
158 #define DMA_CCR_EVT_NO_STATUS		0x00000000
159 #define DMA_CCR_EVT_UNDERRUN		0x00000001
160 #define DMA_CCR_EVT_OVERRUN		0x00000002
161 #define DMA_CCR_EVT_DESP_READ		0x00000003
162 #define DMA_CCR_EVT_DATA_RW		0x00000004
163 #define DMA_CCR_EVT_EARLY_END		0x00000005
164 #define DMA_CCR_EVT_SUCCESS		0x0000000F
165 
166 #define PDMA_READ			0x00
167 #define PDMA_WRITE			0x01
168 
169 #define WMT_SD_POWER_OFF		0
170 #define WMT_SD_POWER_ON			1
171 
172 struct wmt_dma_descriptor {
173 	u32 flags;
174 	u32 data_buffer_addr;
175 	u32 branch_addr;
176 	u32 reserved1;
177 };
178 
179 struct wmt_mci_caps {
180 	unsigned int	f_min;
181 	unsigned int	f_max;
182 	u32		ocr_avail;
183 	u32		caps;
184 	u32		max_seg_size;
185 	u32		max_segs;
186 	u32		max_blk_size;
187 };
188 
189 struct wmt_mci_priv {
190 	struct mmc_host *mmc;
191 	void __iomem *sdmmc_base;
192 
193 	int irq_regular;
194 	int irq_dma;
195 
196 	void *dma_desc_buffer;
197 	dma_addr_t dma_desc_device_addr;
198 
199 	struct completion cmdcomp;
200 	struct completion datacomp;
201 
202 	struct completion *comp_cmd;
203 	struct completion *comp_dma;
204 
205 	struct mmc_request *req;
206 	struct mmc_command *cmd;
207 
208 	struct clk *clk_sdmmc;
209 	struct device *dev;
210 
211 	u8 power_inverted;
212 	u8 cd_inverted;
213 };
214 
215 static void wmt_set_sd_power(struct wmt_mci_priv *priv, int enable)
216 {
217 	u32 reg_tmp = readb(priv->sdmmc_base + SDMMC_BUSMODE);
218 
219 	if (enable ^ priv->power_inverted)
220 		reg_tmp &= ~BM_SD_OFF;
221 	else
222 		reg_tmp |= BM_SD_OFF;
223 
224 	writeb(reg_tmp, priv->sdmmc_base + SDMMC_BUSMODE);
225 }
226 
227 static void wmt_mci_read_response(struct mmc_host *mmc)
228 {
229 	struct wmt_mci_priv *priv;
230 	int idx1, idx2;
231 	u8 tmp_resp;
232 	u32 response;
233 
234 	priv = mmc_priv(mmc);
235 
236 	for (idx1 = 0; idx1 < 4; idx1++) {
237 		response = 0;
238 		for (idx2 = 0; idx2 < 4; idx2++) {
239 			if ((idx1 == 3) && (idx2 == 3))
240 				tmp_resp = readb(priv->sdmmc_base + SDMMC_RSP);
241 			else
242 				tmp_resp = readb(priv->sdmmc_base + SDMMC_RSP +
243 						 (idx1*4) + idx2 + 1);
244 			response |= (tmp_resp << (idx2 * 8));
245 		}
246 		priv->cmd->resp[idx1] = cpu_to_be32(response);
247 	}
248 }
249 
250 static void wmt_mci_start_command(struct wmt_mci_priv *priv)
251 {
252 	u32 reg_tmp;
253 
254 	reg_tmp = readb(priv->sdmmc_base + SDMMC_CTLR);
255 	writeb(reg_tmp | CTLR_CMD_START, priv->sdmmc_base + SDMMC_CTLR);
256 }
257 
258 static int wmt_mci_send_command(struct mmc_host *mmc, u8 command, u8 cmdtype,
259 				u32 arg, u8 rsptype)
260 {
261 	struct wmt_mci_priv *priv;
262 	u32 reg_tmp;
263 
264 	priv = mmc_priv(mmc);
265 
266 	/* write command, arg, resptype registers */
267 	writeb(command, priv->sdmmc_base + SDMMC_CMD);
268 	writel(arg, priv->sdmmc_base + SDMMC_ARG);
269 	writeb(rsptype, priv->sdmmc_base + SDMMC_RSPTYPE);
270 
271 	/* reset response FIFO */
272 	reg_tmp = readb(priv->sdmmc_base + SDMMC_CTLR);
273 	writeb(reg_tmp | CTLR_FIFO_RESET, priv->sdmmc_base + SDMMC_CTLR);
274 
275 	/* ensure clock enabled - VT3465 */
276 	wmt_set_sd_power(priv, WMT_SD_POWER_ON);
277 
278 	/* clear status bits */
279 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS0);
280 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS1);
281 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS2);
282 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS3);
283 
284 	/* set command type */
285 	reg_tmp = readb(priv->sdmmc_base + SDMMC_CTLR);
286 	writeb((reg_tmp & 0x0F) | (cmdtype << 4),
287 	       priv->sdmmc_base + SDMMC_CTLR);
288 
289 	return 0;
290 }
291 
292 static void wmt_mci_disable_dma(struct wmt_mci_priv *priv)
293 {
294 	writel(DMA_ISR_INT_STS, priv->sdmmc_base + SDDMA_ISR);
295 	writel(0, priv->sdmmc_base + SDDMA_IER);
296 }
297 
298 static void wmt_complete_data_request(struct wmt_mci_priv *priv)
299 {
300 	struct mmc_request *req;
301 	req = priv->req;
302 
303 	req->data->bytes_xfered = req->data->blksz * req->data->blocks;
304 
305 	/* unmap the DMA pages used for write data */
306 	if (req->data->flags & MMC_DATA_WRITE)
307 		dma_unmap_sg(mmc_dev(priv->mmc), req->data->sg,
308 			     req->data->sg_len, DMA_TO_DEVICE);
309 	else
310 		dma_unmap_sg(mmc_dev(priv->mmc), req->data->sg,
311 			     req->data->sg_len, DMA_FROM_DEVICE);
312 
313 	/* Check if the DMA ISR returned a data error */
314 	if ((req->cmd->error) || (req->data->error))
315 		mmc_request_done(priv->mmc, req);
316 	else {
317 		wmt_mci_read_response(priv->mmc);
318 		if (!req->data->stop) {
319 			/* single-block read/write requests end here */
320 			mmc_request_done(priv->mmc, req);
321 		} else {
322 			/*
323 			 * we change the priv->cmd variable so the response is
324 			 * stored in the stop struct rather than the original
325 			 * calling command struct
326 			 */
327 			priv->comp_cmd = &priv->cmdcomp;
328 			init_completion(priv->comp_cmd);
329 			priv->cmd = req->data->stop;
330 			wmt_mci_send_command(priv->mmc, req->data->stop->opcode,
331 					     7, req->data->stop->arg, 9);
332 			wmt_mci_start_command(priv);
333 		}
334 	}
335 }
336 
337 static irqreturn_t wmt_mci_dma_isr(int irq_num, void *data)
338 {
339 	struct wmt_mci_priv *priv;
340 
341 	int status;
342 
343 	priv = (struct wmt_mci_priv *)data;
344 
345 	status = readl(priv->sdmmc_base + SDDMA_CCR) & 0x0F;
346 
347 	if (status != DMA_CCR_EVT_SUCCESS) {
348 		dev_err(priv->dev, "DMA Error: Status = %d\n", status);
349 		priv->req->data->error = -ETIMEDOUT;
350 		complete(priv->comp_dma);
351 		return IRQ_HANDLED;
352 	}
353 
354 	priv->req->data->error = 0;
355 
356 	wmt_mci_disable_dma(priv);
357 
358 	complete(priv->comp_dma);
359 
360 	if (priv->comp_cmd) {
361 		if (completion_done(priv->comp_cmd)) {
362 			/*
363 			 * if the command (regular) interrupt has already
364 			 * completed, finish off the request otherwise we wait
365 			 * for the command interrupt and finish from there.
366 			 */
367 			wmt_complete_data_request(priv);
368 		}
369 	}
370 
371 	return IRQ_HANDLED;
372 }
373 
374 static irqreturn_t wmt_mci_regular_isr(int irq_num, void *data)
375 {
376 	struct wmt_mci_priv *priv;
377 	u32 status0;
378 	u32 status1;
379 	u32 status2;
380 	u32 reg_tmp;
381 	int cmd_done;
382 
383 	priv = (struct wmt_mci_priv *)data;
384 	cmd_done = 0;
385 	status0 = readb(priv->sdmmc_base + SDMMC_STS0);
386 	status1 = readb(priv->sdmmc_base + SDMMC_STS1);
387 	status2 = readb(priv->sdmmc_base + SDMMC_STS2);
388 
389 	/* Check for card insertion */
390 	reg_tmp = readb(priv->sdmmc_base + SDMMC_INTMASK0);
391 	if ((reg_tmp & INT0_DI_INT_EN) && (status0 & STS0_DEVICE_INS)) {
392 		mmc_detect_change(priv->mmc, 0);
393 		if (priv->cmd)
394 			priv->cmd->error = -ETIMEDOUT;
395 		if (priv->comp_cmd)
396 			complete(priv->comp_cmd);
397 		if (priv->comp_dma) {
398 			wmt_mci_disable_dma(priv);
399 			complete(priv->comp_dma);
400 		}
401 		writeb(STS0_DEVICE_INS, priv->sdmmc_base + SDMMC_STS0);
402 		return IRQ_HANDLED;
403 	}
404 
405 	if ((!priv->req->data) ||
406 	    ((priv->req->data->stop) && (priv->cmd == priv->req->data->stop))) {
407 		/* handle non-data & stop_transmission requests */
408 		if (status1 & STS1_CMDRSP_DONE) {
409 			priv->cmd->error = 0;
410 			cmd_done = 1;
411 		} else if ((status1 & STS1_RSP_TIMEOUT) ||
412 			   (status1 & STS1_DATA_TIMEOUT)) {
413 			priv->cmd->error = -ETIMEDOUT;
414 			cmd_done = 1;
415 		}
416 
417 		if (cmd_done) {
418 			priv->comp_cmd = NULL;
419 
420 			if (!priv->cmd->error)
421 				wmt_mci_read_response(priv->mmc);
422 
423 			priv->cmd = NULL;
424 
425 			mmc_request_done(priv->mmc, priv->req);
426 		}
427 	} else {
428 		/* handle data requests */
429 		if (status1 & STS1_CMDRSP_DONE) {
430 			if (priv->cmd)
431 				priv->cmd->error = 0;
432 			if (priv->comp_cmd)
433 				complete(priv->comp_cmd);
434 		}
435 
436 		if ((status1 & STS1_RSP_TIMEOUT) ||
437 		    (status1 & STS1_DATA_TIMEOUT)) {
438 			if (priv->cmd)
439 				priv->cmd->error = -ETIMEDOUT;
440 			if (priv->comp_cmd)
441 				complete(priv->comp_cmd);
442 			if (priv->comp_dma) {
443 				wmt_mci_disable_dma(priv);
444 				complete(priv->comp_dma);
445 			}
446 		}
447 
448 		if (priv->comp_dma) {
449 			/*
450 			 * If the dma interrupt has already completed, finish
451 			 * off the request; otherwise we wait for the DMA
452 			 * interrupt and finish from there.
453 			 */
454 			if (completion_done(priv->comp_dma))
455 				wmt_complete_data_request(priv);
456 		}
457 	}
458 
459 	writeb(status0, priv->sdmmc_base + SDMMC_STS0);
460 	writeb(status1, priv->sdmmc_base + SDMMC_STS1);
461 	writeb(status2, priv->sdmmc_base + SDMMC_STS2);
462 
463 	return IRQ_HANDLED;
464 }
465 
466 static void wmt_reset_hardware(struct mmc_host *mmc)
467 {
468 	struct wmt_mci_priv *priv;
469 	u32 reg_tmp;
470 
471 	priv = mmc_priv(mmc);
472 
473 	/* reset controller */
474 	reg_tmp = readb(priv->sdmmc_base + SDMMC_BUSMODE);
475 	writeb(reg_tmp | BM_SOFT_RESET, priv->sdmmc_base + SDMMC_BUSMODE);
476 
477 	/* reset response FIFO */
478 	reg_tmp = readb(priv->sdmmc_base + SDMMC_CTLR);
479 	writeb(reg_tmp | CTLR_FIFO_RESET, priv->sdmmc_base + SDMMC_CTLR);
480 
481 	/* enable GPI pin to detect card */
482 	writew(BLKL_INT_ENABLE | BLKL_GPI_CD, priv->sdmmc_base + SDMMC_BLKLEN);
483 
484 	/* clear interrupt status */
485 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS0);
486 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS1);
487 
488 	/* setup interrupts */
489 	writeb(INT0_CD_INT_EN | INT0_DI_INT_EN, priv->sdmmc_base +
490 	       SDMMC_INTMASK0);
491 	writeb(INT1_DATA_TOUT_INT_EN | INT1_CMD_RES_TRAN_DONE_INT_EN |
492 	       INT1_CMD_RES_TOUT_INT_EN, priv->sdmmc_base + SDMMC_INTMASK1);
493 
494 	/* set the DMA timeout */
495 	writew(8191, priv->sdmmc_base + SDMMC_DMATIMEOUT);
496 
497 	/* auto clock freezing enable */
498 	reg_tmp = readb(priv->sdmmc_base + SDMMC_STS2);
499 	writeb(reg_tmp | STS2_DIS_FORCECLK, priv->sdmmc_base + SDMMC_STS2);
500 
501 	/* set a default clock speed of 400Khz */
502 	clk_set_rate(priv->clk_sdmmc, 400000);
503 }
504 
505 static int wmt_dma_init(struct mmc_host *mmc)
506 {
507 	struct wmt_mci_priv *priv;
508 
509 	priv = mmc_priv(mmc);
510 
511 	writel(DMA_GCR_SOFT_RESET, priv->sdmmc_base + SDDMA_GCR);
512 	writel(DMA_GCR_DMA_EN, priv->sdmmc_base + SDDMA_GCR);
513 	if ((readl(priv->sdmmc_base + SDDMA_GCR) & DMA_GCR_DMA_EN) != 0)
514 		return 0;
515 	else
516 		return 1;
517 }
518 
519 static void wmt_dma_init_descriptor(struct wmt_dma_descriptor *desc,
520 		u16 req_count, u32 buffer_addr, u32 branch_addr, int end)
521 {
522 	desc->flags = 0x40000000 | req_count;
523 	if (end)
524 		desc->flags |= 0x80000000;
525 	desc->data_buffer_addr = buffer_addr;
526 	desc->branch_addr = branch_addr;
527 }
528 
529 static void wmt_dma_config(struct mmc_host *mmc, u32 descaddr, u8 dir)
530 {
531 	struct wmt_mci_priv *priv;
532 	u32 reg_tmp;
533 
534 	priv = mmc_priv(mmc);
535 
536 	/* Enable DMA Interrupts */
537 	writel(DMA_IER_INT_EN, priv->sdmmc_base + SDDMA_IER);
538 
539 	/* Write DMA Descriptor Pointer Register */
540 	writel(descaddr, priv->sdmmc_base + SDDMA_DESPR);
541 
542 	writel(0x00, priv->sdmmc_base + SDDMA_CCR);
543 
544 	if (dir == PDMA_WRITE) {
545 		reg_tmp = readl(priv->sdmmc_base + SDDMA_CCR);
546 		writel(reg_tmp & DMA_CCR_IF_TO_PERIPHERAL, priv->sdmmc_base +
547 		       SDDMA_CCR);
548 	} else {
549 		reg_tmp = readl(priv->sdmmc_base + SDDMA_CCR);
550 		writel(reg_tmp | DMA_CCR_PERIPHERAL_TO_IF, priv->sdmmc_base +
551 		       SDDMA_CCR);
552 	}
553 }
554 
555 static void wmt_dma_start(struct wmt_mci_priv *priv)
556 {
557 	u32 reg_tmp;
558 
559 	reg_tmp = readl(priv->sdmmc_base + SDDMA_CCR);
560 	writel(reg_tmp | DMA_CCR_RUN, priv->sdmmc_base + SDDMA_CCR);
561 }
562 
563 static void wmt_mci_request(struct mmc_host *mmc, struct mmc_request *req)
564 {
565 	struct wmt_mci_priv *priv;
566 	struct wmt_dma_descriptor *desc;
567 	u8 command;
568 	u8 cmdtype;
569 	u32 arg;
570 	u8 rsptype;
571 	u32 reg_tmp;
572 
573 	struct scatterlist *sg;
574 	int i;
575 	int sg_cnt;
576 	int offset;
577 	u32 dma_address;
578 	int desc_cnt;
579 
580 	priv = mmc_priv(mmc);
581 	priv->req = req;
582 
583 	/*
584 	 * Use the cmd variable to pass a pointer to the resp[] structure
585 	 * This is required on multi-block requests to pass the pointer to the
586 	 * stop command
587 	 */
588 	priv->cmd = req->cmd;
589 
590 	command = req->cmd->opcode;
591 	arg = req->cmd->arg;
592 	rsptype = mmc_resp_type(req->cmd);
593 	cmdtype = 0;
594 
595 	/* rsptype=7 only valid for SPI commands - should be =2 for SD */
596 	if (rsptype == 7)
597 		rsptype = 2;
598 	/* rsptype=21 is R1B, convert for controller */
599 	if (rsptype == 21)
600 		rsptype = 9;
601 
602 	if (!req->data) {
603 		wmt_mci_send_command(mmc, command, cmdtype, arg, rsptype);
604 		wmt_mci_start_command(priv);
605 		/* completion is now handled in the regular_isr() */
606 	}
607 	if (req->data) {
608 		priv->comp_cmd = &priv->cmdcomp;
609 		init_completion(priv->comp_cmd);
610 
611 		wmt_dma_init(mmc);
612 
613 		/* set controller data length */
614 		reg_tmp = readw(priv->sdmmc_base + SDMMC_BLKLEN);
615 		writew((reg_tmp & 0xF800) | (req->data->blksz - 1),
616 		       priv->sdmmc_base + SDMMC_BLKLEN);
617 
618 		/* set controller block count */
619 		writew(req->data->blocks, priv->sdmmc_base + SDMMC_BLKCNT);
620 
621 		desc = (struct wmt_dma_descriptor *)priv->dma_desc_buffer;
622 
623 		if (req->data->flags & MMC_DATA_WRITE) {
624 			sg_cnt = dma_map_sg(mmc_dev(mmc), req->data->sg,
625 					    req->data->sg_len, DMA_TO_DEVICE);
626 			cmdtype = 1;
627 			if (req->data->blocks > 1)
628 				cmdtype = 3;
629 		} else {
630 			sg_cnt = dma_map_sg(mmc_dev(mmc), req->data->sg,
631 					    req->data->sg_len, DMA_FROM_DEVICE);
632 			cmdtype = 2;
633 			if (req->data->blocks > 1)
634 				cmdtype = 4;
635 		}
636 
637 		dma_address = priv->dma_desc_device_addr + 16;
638 		desc_cnt = 0;
639 
640 		for_each_sg(req->data->sg, sg, sg_cnt, i) {
641 			offset = 0;
642 			while (offset < sg_dma_len(sg)) {
643 				wmt_dma_init_descriptor(desc, req->data->blksz,
644 						sg_dma_address(sg)+offset,
645 						dma_address, 0);
646 				desc++;
647 				desc_cnt++;
648 				offset += req->data->blksz;
649 				dma_address += 16;
650 				if (desc_cnt == req->data->blocks)
651 					break;
652 			}
653 		}
654 		desc--;
655 		desc->flags |= 0x80000000;
656 
657 		if (req->data->flags & MMC_DATA_WRITE)
658 			wmt_dma_config(mmc, priv->dma_desc_device_addr,
659 				       PDMA_WRITE);
660 		else
661 			wmt_dma_config(mmc, priv->dma_desc_device_addr,
662 				       PDMA_READ);
663 
664 		wmt_mci_send_command(mmc, command, cmdtype, arg, rsptype);
665 
666 		priv->comp_dma = &priv->datacomp;
667 		init_completion(priv->comp_dma);
668 
669 		wmt_dma_start(priv);
670 		wmt_mci_start_command(priv);
671 	}
672 }
673 
674 static void wmt_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
675 {
676 	struct wmt_mci_priv *priv;
677 	u32 busmode, extctrl;
678 
679 	priv = mmc_priv(mmc);
680 
681 	if (ios->power_mode == MMC_POWER_UP) {
682 		wmt_reset_hardware(mmc);
683 
684 		wmt_set_sd_power(priv, WMT_SD_POWER_ON);
685 	}
686 	if (ios->power_mode == MMC_POWER_OFF)
687 		wmt_set_sd_power(priv, WMT_SD_POWER_OFF);
688 
689 	if (ios->clock != 0)
690 		clk_set_rate(priv->clk_sdmmc, ios->clock);
691 
692 	busmode = readb(priv->sdmmc_base + SDMMC_BUSMODE);
693 	extctrl = readb(priv->sdmmc_base + SDMMC_EXTCTRL);
694 
695 	busmode &= ~(BM_EIGHTBIT_MODE | BM_FOURBIT_MODE);
696 	extctrl &= ~EXT_EIGHTBIT;
697 
698 	switch (ios->bus_width) {
699 	case MMC_BUS_WIDTH_8:
700 		busmode |= BM_EIGHTBIT_MODE;
701 		extctrl |= EXT_EIGHTBIT;
702 		break;
703 	case MMC_BUS_WIDTH_4:
704 		busmode |= BM_FOURBIT_MODE;
705 		break;
706 	case MMC_BUS_WIDTH_1:
707 		break;
708 	}
709 
710 	writeb(busmode, priv->sdmmc_base + SDMMC_BUSMODE);
711 	writeb(extctrl, priv->sdmmc_base + SDMMC_EXTCTRL);
712 }
713 
714 static int wmt_mci_get_ro(struct mmc_host *mmc)
715 {
716 	struct wmt_mci_priv *priv = mmc_priv(mmc);
717 
718 	return !(readb(priv->sdmmc_base + SDMMC_STS0) & STS0_WRITE_PROTECT);
719 }
720 
721 static int wmt_mci_get_cd(struct mmc_host *mmc)
722 {
723 	struct wmt_mci_priv *priv = mmc_priv(mmc);
724 	u32 cd = (readb(priv->sdmmc_base + SDMMC_STS0) & STS0_CD_GPI) >> 3;
725 
726 	return !(cd ^ priv->cd_inverted);
727 }
728 
729 static const struct mmc_host_ops wmt_mci_ops = {
730 	.request = wmt_mci_request,
731 	.set_ios = wmt_mci_set_ios,
732 	.get_ro = wmt_mci_get_ro,
733 	.get_cd = wmt_mci_get_cd,
734 };
735 
736 /* Controller capabilities */
737 static struct wmt_mci_caps wm8505_caps = {
738 	.f_min = 390425,
739 	.f_max = 50000000,
740 	.ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34,
741 	.caps = MMC_CAP_4_BIT_DATA | MMC_CAP_MMC_HIGHSPEED |
742 		MMC_CAP_SD_HIGHSPEED,
743 	.max_seg_size = 65024,
744 	.max_segs = 128,
745 	.max_blk_size = 2048,
746 };
747 
748 static const struct of_device_id wmt_mci_dt_ids[] = {
749 	{ .compatible = "wm,wm8505-sdhc", .data = &wm8505_caps },
750 	{ /* Sentinel */ },
751 };
752 
753 static int wmt_mci_probe(struct platform_device *pdev)
754 {
755 	struct mmc_host *mmc;
756 	struct wmt_mci_priv *priv;
757 	struct device_node *np = pdev->dev.of_node;
758 	const struct of_device_id *of_id =
759 		of_match_device(wmt_mci_dt_ids, &pdev->dev);
760 	const struct wmt_mci_caps *wmt_caps;
761 	int ret;
762 	int regular_irq, dma_irq;
763 
764 	if (!of_id || !of_id->data) {
765 		dev_err(&pdev->dev, "Controller capabilities data missing\n");
766 		return -EFAULT;
767 	}
768 
769 	wmt_caps = of_id->data;
770 
771 	if (!np) {
772 		dev_err(&pdev->dev, "Missing SDMMC description in devicetree\n");
773 		return -EFAULT;
774 	}
775 
776 	regular_irq = irq_of_parse_and_map(np, 0);
777 	dma_irq = irq_of_parse_and_map(np, 1);
778 
779 	if (!regular_irq || !dma_irq) {
780 		dev_err(&pdev->dev, "Getting IRQs failed!\n");
781 		ret = -ENXIO;
782 		goto fail1;
783 	}
784 
785 	mmc = mmc_alloc_host(sizeof(struct wmt_mci_priv), &pdev->dev);
786 	if (!mmc) {
787 		dev_err(&pdev->dev, "Failed to allocate mmc_host\n");
788 		ret = -ENOMEM;
789 		goto fail1;
790 	}
791 
792 	mmc->ops = &wmt_mci_ops;
793 	mmc->f_min = wmt_caps->f_min;
794 	mmc->f_max = wmt_caps->f_max;
795 	mmc->ocr_avail = wmt_caps->ocr_avail;
796 	mmc->caps = wmt_caps->caps;
797 
798 	mmc->max_seg_size = wmt_caps->max_seg_size;
799 	mmc->max_segs = wmt_caps->max_segs;
800 	mmc->max_blk_size = wmt_caps->max_blk_size;
801 
802 	mmc->max_req_size = (16*512*mmc->max_segs);
803 	mmc->max_blk_count = mmc->max_req_size / 512;
804 
805 	priv = mmc_priv(mmc);
806 	priv->mmc = mmc;
807 	priv->dev = &pdev->dev;
808 
809 	priv->power_inverted = 0;
810 	priv->cd_inverted = 0;
811 
812 	if (of_get_property(np, "sdon-inverted", NULL))
813 		priv->power_inverted = 1;
814 	if (of_get_property(np, "cd-inverted", NULL))
815 		priv->cd_inverted = 1;
816 
817 	priv->sdmmc_base = of_iomap(np, 0);
818 	if (!priv->sdmmc_base) {
819 		dev_err(&pdev->dev, "Failed to map IO space\n");
820 		ret = -ENOMEM;
821 		goto fail2;
822 	}
823 
824 	priv->irq_regular = regular_irq;
825 	priv->irq_dma = dma_irq;
826 
827 	ret = request_irq(regular_irq, wmt_mci_regular_isr, 0, "sdmmc", priv);
828 	if (ret) {
829 		dev_err(&pdev->dev, "Register regular IRQ fail\n");
830 		goto fail3;
831 	}
832 
833 	ret = request_irq(dma_irq, wmt_mci_dma_isr, 0, "sdmmc", priv);
834 	if (ret) {
835 		dev_err(&pdev->dev, "Register DMA IRQ fail\n");
836 		goto fail4;
837 	}
838 
839 	/* alloc some DMA buffers for descriptors/transfers */
840 	priv->dma_desc_buffer = dma_alloc_coherent(&pdev->dev,
841 						   mmc->max_blk_count * 16,
842 						   &priv->dma_desc_device_addr,
843 						   GFP_KERNEL);
844 	if (!priv->dma_desc_buffer) {
845 		dev_err(&pdev->dev, "DMA alloc fail\n");
846 		ret = -EPERM;
847 		goto fail5;
848 	}
849 
850 	platform_set_drvdata(pdev, mmc);
851 
852 	priv->clk_sdmmc = of_clk_get(np, 0);
853 	if (IS_ERR(priv->clk_sdmmc)) {
854 		dev_err(&pdev->dev, "Error getting clock\n");
855 		ret = PTR_ERR(priv->clk_sdmmc);
856 		goto fail5;
857 	}
858 
859 	ret = clk_prepare_enable(priv->clk_sdmmc);
860 	if (ret)
861 		goto fail6;
862 
863 	/* configure the controller to a known 'ready' state */
864 	wmt_reset_hardware(mmc);
865 
866 	mmc_add_host(mmc);
867 
868 	dev_info(&pdev->dev, "WMT SDHC Controller initialized\n");
869 
870 	return 0;
871 fail6:
872 	clk_put(priv->clk_sdmmc);
873 fail5:
874 	free_irq(dma_irq, priv);
875 fail4:
876 	free_irq(regular_irq, priv);
877 fail3:
878 	iounmap(priv->sdmmc_base);
879 fail2:
880 	mmc_free_host(mmc);
881 fail1:
882 	return ret;
883 }
884 
885 static int wmt_mci_remove(struct platform_device *pdev)
886 {
887 	struct mmc_host *mmc;
888 	struct wmt_mci_priv *priv;
889 	struct resource *res;
890 	u32 reg_tmp;
891 
892 	mmc = platform_get_drvdata(pdev);
893 	priv = mmc_priv(mmc);
894 
895 	/* reset SD controller */
896 	reg_tmp = readb(priv->sdmmc_base + SDMMC_BUSMODE);
897 	writel(reg_tmp | BM_SOFT_RESET, priv->sdmmc_base + SDMMC_BUSMODE);
898 	reg_tmp = readw(priv->sdmmc_base + SDMMC_BLKLEN);
899 	writew(reg_tmp & ~(0xA000), priv->sdmmc_base + SDMMC_BLKLEN);
900 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS0);
901 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS1);
902 
903 	/* release the dma buffers */
904 	dma_free_coherent(&pdev->dev, priv->mmc->max_blk_count * 16,
905 			  priv->dma_desc_buffer, priv->dma_desc_device_addr);
906 
907 	mmc_remove_host(mmc);
908 
909 	free_irq(priv->irq_regular, priv);
910 	free_irq(priv->irq_dma, priv);
911 
912 	iounmap(priv->sdmmc_base);
913 
914 	clk_disable_unprepare(priv->clk_sdmmc);
915 	clk_put(priv->clk_sdmmc);
916 
917 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
918 	release_mem_region(res->start, resource_size(res));
919 
920 	mmc_free_host(mmc);
921 
922 	dev_info(&pdev->dev, "WMT MCI device removed\n");
923 
924 	return 0;
925 }
926 
927 #ifdef CONFIG_PM
928 static int wmt_mci_suspend(struct device *dev)
929 {
930 	u32 reg_tmp;
931 	struct mmc_host *mmc = dev_get_drvdata(dev);
932 	struct wmt_mci_priv *priv;
933 
934 	if (!mmc)
935 		return 0;
936 
937 	priv = mmc_priv(mmc);
938 	reg_tmp = readb(priv->sdmmc_base + SDMMC_BUSMODE);
939 	writeb(reg_tmp | BM_SOFT_RESET, priv->sdmmc_base +
940 	       SDMMC_BUSMODE);
941 
942 	reg_tmp = readw(priv->sdmmc_base + SDMMC_BLKLEN);
943 	writew(reg_tmp & 0x5FFF, priv->sdmmc_base + SDMMC_BLKLEN);
944 
945 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS0);
946 	writeb(0xFF, priv->sdmmc_base + SDMMC_STS1);
947 
948 	clk_disable(priv->clk_sdmmc);
949 	return 0;
950 }
951 
952 static int wmt_mci_resume(struct device *dev)
953 {
954 	u32 reg_tmp;
955 	struct mmc_host *mmc = dev_get_drvdata(dev);
956 	struct wmt_mci_priv *priv;
957 
958 	if (mmc) {
959 		priv = mmc_priv(mmc);
960 		clk_enable(priv->clk_sdmmc);
961 
962 		reg_tmp = readb(priv->sdmmc_base + SDMMC_BUSMODE);
963 		writeb(reg_tmp | BM_SOFT_RESET, priv->sdmmc_base +
964 		       SDMMC_BUSMODE);
965 
966 		reg_tmp = readw(priv->sdmmc_base + SDMMC_BLKLEN);
967 		writew(reg_tmp | (BLKL_GPI_CD | BLKL_INT_ENABLE),
968 		       priv->sdmmc_base + SDMMC_BLKLEN);
969 
970 		reg_tmp = readb(priv->sdmmc_base + SDMMC_INTMASK0);
971 		writeb(reg_tmp | INT0_DI_INT_EN, priv->sdmmc_base +
972 		       SDMMC_INTMASK0);
973 
974 	}
975 
976 	return 0;
977 }
978 
979 static const struct dev_pm_ops wmt_mci_pm = {
980 	.suspend        = wmt_mci_suspend,
981 	.resume         = wmt_mci_resume,
982 };
983 
984 #define wmt_mci_pm_ops (&wmt_mci_pm)
985 
986 #else	/* !CONFIG_PM */
987 
988 #define wmt_mci_pm_ops NULL
989 
990 #endif
991 
992 static struct platform_driver wmt_mci_driver = {
993 	.probe = wmt_mci_probe,
994 	.remove = wmt_mci_remove,
995 	.driver = {
996 		.name = DRIVER_NAME,
997 		.pm = wmt_mci_pm_ops,
998 		.of_match_table = wmt_mci_dt_ids,
999 	},
1000 };
1001 
1002 module_platform_driver(wmt_mci_driver);
1003 
1004 MODULE_DESCRIPTION("Wondermedia MMC/SD Driver");
1005 MODULE_AUTHOR("Tony Prisk");
1006 MODULE_LICENSE("GPL v2");
1007 MODULE_DEVICE_TABLE(of, wmt_mci_dt_ids);
1008