xref: /linux/drivers/mmc/host/davinci_mmc.c (revision 7e30b8decbb1a5853522936eb613803a480312c3)
1 /*
2  * davinci_mmc.c - TI DaVinci MMC/SD/SDIO driver
3  *
4  * Copyright (C) 2006 Texas Instruments.
5  *       Original author: Purushotam Kumar
6  * Copyright (C) 2009 David Brownell
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #include <linux/module.h>
24 #include <linux/ioport.h>
25 #include <linux/platform_device.h>
26 #include <linux/clk.h>
27 #include <linux/err.h>
28 #include <linux/cpufreq.h>
29 #include <linux/mmc/host.h>
30 #include <linux/io.h>
31 #include <linux/irq.h>
32 #include <linux/delay.h>
33 #include <linux/dma-mapping.h>
34 #include <linux/mmc/mmc.h>
35 
36 #include <mach/mmc.h>
37 #include <mach/edma.h>
38 
39 /*
40  * Register Definitions
41  */
42 #define DAVINCI_MMCCTL       0x00 /* Control Register                  */
43 #define DAVINCI_MMCCLK       0x04 /* Memory Clock Control Register     */
44 #define DAVINCI_MMCST0       0x08 /* Status Register 0                 */
45 #define DAVINCI_MMCST1       0x0C /* Status Register 1                 */
46 #define DAVINCI_MMCIM        0x10 /* Interrupt Mask Register           */
47 #define DAVINCI_MMCTOR       0x14 /* Response Time-Out Register        */
48 #define DAVINCI_MMCTOD       0x18 /* Data Read Time-Out Register       */
49 #define DAVINCI_MMCBLEN      0x1C /* Block Length Register             */
50 #define DAVINCI_MMCNBLK      0x20 /* Number of Blocks Register         */
51 #define DAVINCI_MMCNBLC      0x24 /* Number of Blocks Counter Register */
52 #define DAVINCI_MMCDRR       0x28 /* Data Receive Register             */
53 #define DAVINCI_MMCDXR       0x2C /* Data Transmit Register            */
54 #define DAVINCI_MMCCMD       0x30 /* Command Register                  */
55 #define DAVINCI_MMCARGHL     0x34 /* Argument Register                 */
56 #define DAVINCI_MMCRSP01     0x38 /* Response Register 0 and 1         */
57 #define DAVINCI_MMCRSP23     0x3C /* Response Register 0 and 1         */
58 #define DAVINCI_MMCRSP45     0x40 /* Response Register 0 and 1         */
59 #define DAVINCI_MMCRSP67     0x44 /* Response Register 0 and 1         */
60 #define DAVINCI_MMCDRSP      0x48 /* Data Response Register            */
61 #define DAVINCI_MMCETOK      0x4C
62 #define DAVINCI_MMCCIDX      0x50 /* Command Index Register            */
63 #define DAVINCI_MMCCKC       0x54
64 #define DAVINCI_MMCTORC      0x58
65 #define DAVINCI_MMCTODC      0x5C
66 #define DAVINCI_MMCBLNC      0x60
67 #define DAVINCI_SDIOCTL      0x64
68 #define DAVINCI_SDIOST0      0x68
69 #define DAVINCI_SDIOEN       0x6C
70 #define DAVINCI_SDIOST       0x70
71 #define DAVINCI_MMCFIFOCTL   0x74 /* FIFO Control Register             */
72 
73 /* DAVINCI_MMCCTL definitions */
74 #define MMCCTL_DATRST         (1 << 0)
75 #define MMCCTL_CMDRST         (1 << 1)
76 #define MMCCTL_WIDTH_4_BIT    (1 << 2)
77 #define MMCCTL_DATEG_DISABLED (0 << 6)
78 #define MMCCTL_DATEG_RISING   (1 << 6)
79 #define MMCCTL_DATEG_FALLING  (2 << 6)
80 #define MMCCTL_DATEG_BOTH     (3 << 6)
81 #define MMCCTL_PERMDR_LE      (0 << 9)
82 #define MMCCTL_PERMDR_BE      (1 << 9)
83 #define MMCCTL_PERMDX_LE      (0 << 10)
84 #define MMCCTL_PERMDX_BE      (1 << 10)
85 
86 /* DAVINCI_MMCCLK definitions */
87 #define MMCCLK_CLKEN          (1 << 8)
88 #define MMCCLK_CLKRT_MASK     (0xFF << 0)
89 
90 /* IRQ bit definitions, for DAVINCI_MMCST0 and DAVINCI_MMCIM */
91 #define MMCST0_DATDNE         BIT(0)	/* data done */
92 #define MMCST0_BSYDNE         BIT(1)	/* busy done */
93 #define MMCST0_RSPDNE         BIT(2)	/* command done */
94 #define MMCST0_TOUTRD         BIT(3)	/* data read timeout */
95 #define MMCST0_TOUTRS         BIT(4)	/* command response timeout */
96 #define MMCST0_CRCWR          BIT(5)	/* data write CRC error */
97 #define MMCST0_CRCRD          BIT(6)	/* data read CRC error */
98 #define MMCST0_CRCRS          BIT(7)	/* command response CRC error */
99 #define MMCST0_DXRDY          BIT(9)	/* data transmit ready (fifo empty) */
100 #define MMCST0_DRRDY          BIT(10)	/* data receive ready (data in fifo)*/
101 #define MMCST0_DATED          BIT(11)	/* DAT3 edge detect */
102 #define MMCST0_TRNDNE         BIT(12)	/* transfer done */
103 
104 /* DAVINCI_MMCST1 definitions */
105 #define MMCST1_BUSY           (1 << 0)
106 
107 /* DAVINCI_MMCCMD definitions */
108 #define MMCCMD_CMD_MASK       (0x3F << 0)
109 #define MMCCMD_PPLEN          (1 << 7)
110 #define MMCCMD_BSYEXP         (1 << 8)
111 #define MMCCMD_RSPFMT_MASK    (3 << 9)
112 #define MMCCMD_RSPFMT_NONE    (0 << 9)
113 #define MMCCMD_RSPFMT_R1456   (1 << 9)
114 #define MMCCMD_RSPFMT_R2      (2 << 9)
115 #define MMCCMD_RSPFMT_R3      (3 << 9)
116 #define MMCCMD_DTRW           (1 << 11)
117 #define MMCCMD_STRMTP         (1 << 12)
118 #define MMCCMD_WDATX          (1 << 13)
119 #define MMCCMD_INITCK         (1 << 14)
120 #define MMCCMD_DCLR           (1 << 15)
121 #define MMCCMD_DMATRIG        (1 << 16)
122 
123 /* DAVINCI_MMCFIFOCTL definitions */
124 #define MMCFIFOCTL_FIFORST    (1 << 0)
125 #define MMCFIFOCTL_FIFODIR_WR (1 << 1)
126 #define MMCFIFOCTL_FIFODIR_RD (0 << 1)
127 #define MMCFIFOCTL_FIFOLEV    (1 << 2) /* 0 = 128 bits, 1 = 256 bits */
128 #define MMCFIFOCTL_ACCWD_4    (0 << 3) /* access width of 4 bytes    */
129 #define MMCFIFOCTL_ACCWD_3    (1 << 3) /* access width of 3 bytes    */
130 #define MMCFIFOCTL_ACCWD_2    (2 << 3) /* access width of 2 bytes    */
131 #define MMCFIFOCTL_ACCWD_1    (3 << 3) /* access width of 1 byte     */
132 
133 
134 /* MMCSD Init clock in Hz in opendrain mode */
135 #define MMCSD_INIT_CLOCK		200000
136 
137 /*
138  * One scatterlist dma "segment" is at most MAX_CCNT rw_threshold units,
139  * and we handle up to NR_SG segments.  MMC_BLOCK_BOUNCE kicks in only
140  * for drivers with max_hw_segs == 1, making the segments bigger (64KB)
141  * than the page or two that's otherwise typical.  NR_SG == 16 gives at
142  * least the same throughput boost, using EDMA transfer linkage instead
143  * of spending CPU time copying pages.
144  */
145 #define MAX_CCNT	((1 << 16) - 1)
146 
147 #define NR_SG		16
148 
149 static unsigned rw_threshold = 32;
150 module_param(rw_threshold, uint, S_IRUGO);
151 MODULE_PARM_DESC(rw_threshold,
152 		"Read/Write threshold. Default = 32");
153 
154 static unsigned __initdata use_dma = 1;
155 module_param(use_dma, uint, 0);
156 MODULE_PARM_DESC(use_dma, "Whether to use DMA or not. Default = 1");
157 
158 struct mmc_davinci_host {
159 	struct mmc_command *cmd;
160 	struct mmc_data *data;
161 	struct mmc_host *mmc;
162 	struct clk *clk;
163 	unsigned int mmc_input_clk;
164 	void __iomem *base;
165 	struct resource *mem_res;
166 	int irq;
167 	unsigned char bus_mode;
168 
169 #define DAVINCI_MMC_DATADIR_NONE	0
170 #define DAVINCI_MMC_DATADIR_READ	1
171 #define DAVINCI_MMC_DATADIR_WRITE	2
172 	unsigned char data_dir;
173 
174 	/* buffer is used during PIO of one scatterlist segment, and
175 	 * is updated along with buffer_bytes_left.  bytes_left applies
176 	 * to all N blocks of the PIO transfer.
177 	 */
178 	u8 *buffer;
179 	u32 buffer_bytes_left;
180 	u32 bytes_left;
181 
182 	u32 rxdma, txdma;
183 	bool use_dma;
184 	bool do_dma;
185 
186 	/* Scatterlist DMA uses one or more parameter RAM entries:
187 	 * the main one (associated with rxdma or txdma) plus zero or
188 	 * more links.  The entries for a given transfer differ only
189 	 * by memory buffer (address, length) and link field.
190 	 */
191 	struct edmacc_param	tx_template;
192 	struct edmacc_param	rx_template;
193 	unsigned		n_link;
194 	u32			links[NR_SG - 1];
195 
196 	/* For PIO we walk scatterlists one segment at a time. */
197 	unsigned int		sg_len;
198 	struct scatterlist *sg;
199 
200 	/* Version of the MMC/SD controller */
201 	u8 version;
202 	/* for ns in one cycle calculation */
203 	unsigned ns_in_one_cycle;
204 #ifdef CONFIG_CPU_FREQ
205 	struct notifier_block	freq_transition;
206 #endif
207 };
208 
209 
210 /* PIO only */
211 static void mmc_davinci_sg_to_buf(struct mmc_davinci_host *host)
212 {
213 	host->buffer_bytes_left = sg_dma_len(host->sg);
214 	host->buffer = sg_virt(host->sg);
215 	if (host->buffer_bytes_left > host->bytes_left)
216 		host->buffer_bytes_left = host->bytes_left;
217 }
218 
219 static void davinci_fifo_data_trans(struct mmc_davinci_host *host,
220 					unsigned int n)
221 {
222 	u8 *p;
223 	unsigned int i;
224 
225 	if (host->buffer_bytes_left == 0) {
226 		host->sg = sg_next(host->data->sg);
227 		mmc_davinci_sg_to_buf(host);
228 	}
229 
230 	p = host->buffer;
231 	if (n > host->buffer_bytes_left)
232 		n = host->buffer_bytes_left;
233 	host->buffer_bytes_left -= n;
234 	host->bytes_left -= n;
235 
236 	/* NOTE:  we never transfer more than rw_threshold bytes
237 	 * to/from the fifo here; there's no I/O overlap.
238 	 * This also assumes that access width( i.e. ACCWD) is 4 bytes
239 	 */
240 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
241 		for (i = 0; i < (n >> 2); i++) {
242 			writel(*((u32 *)p), host->base + DAVINCI_MMCDXR);
243 			p = p + 4;
244 		}
245 		if (n & 3) {
246 			iowrite8_rep(host->base + DAVINCI_MMCDXR, p, (n & 3));
247 			p = p + (n & 3);
248 		}
249 	} else {
250 		for (i = 0; i < (n >> 2); i++) {
251 			*((u32 *)p) = readl(host->base + DAVINCI_MMCDRR);
252 			p  = p + 4;
253 		}
254 		if (n & 3) {
255 			ioread8_rep(host->base + DAVINCI_MMCDRR, p, (n & 3));
256 			p = p + (n & 3);
257 		}
258 	}
259 	host->buffer = p;
260 }
261 
262 static void mmc_davinci_start_command(struct mmc_davinci_host *host,
263 		struct mmc_command *cmd)
264 {
265 	u32 cmd_reg = 0;
266 	u32 im_val;
267 
268 	dev_dbg(mmc_dev(host->mmc), "CMD%d, arg 0x%08x%s\n",
269 		cmd->opcode, cmd->arg,
270 		({ char *s;
271 		switch (mmc_resp_type(cmd)) {
272 		case MMC_RSP_R1:
273 			s = ", R1/R5/R6/R7 response";
274 			break;
275 		case MMC_RSP_R1B:
276 			s = ", R1b response";
277 			break;
278 		case MMC_RSP_R2:
279 			s = ", R2 response";
280 			break;
281 		case MMC_RSP_R3:
282 			s = ", R3/R4 response";
283 			break;
284 		default:
285 			s = ", (R? response)";
286 			break;
287 		}; s; }));
288 	host->cmd = cmd;
289 
290 	switch (mmc_resp_type(cmd)) {
291 	case MMC_RSP_R1B:
292 		/* There's some spec confusion about when R1B is
293 		 * allowed, but if the card doesn't issue a BUSY
294 		 * then it's harmless for us to allow it.
295 		 */
296 		cmd_reg |= MMCCMD_BSYEXP;
297 		/* FALLTHROUGH */
298 	case MMC_RSP_R1:		/* 48 bits, CRC */
299 		cmd_reg |= MMCCMD_RSPFMT_R1456;
300 		break;
301 	case MMC_RSP_R2:		/* 136 bits, CRC */
302 		cmd_reg |= MMCCMD_RSPFMT_R2;
303 		break;
304 	case MMC_RSP_R3:		/* 48 bits, no CRC */
305 		cmd_reg |= MMCCMD_RSPFMT_R3;
306 		break;
307 	default:
308 		cmd_reg |= MMCCMD_RSPFMT_NONE;
309 		dev_dbg(mmc_dev(host->mmc), "unknown resp_type %04x\n",
310 			mmc_resp_type(cmd));
311 		break;
312 	}
313 
314 	/* Set command index */
315 	cmd_reg |= cmd->opcode;
316 
317 	/* Enable EDMA transfer triggers */
318 	if (host->do_dma)
319 		cmd_reg |= MMCCMD_DMATRIG;
320 
321 	if (host->version == MMC_CTLR_VERSION_2 && host->data != NULL &&
322 			host->data_dir == DAVINCI_MMC_DATADIR_READ)
323 		cmd_reg |= MMCCMD_DMATRIG;
324 
325 	/* Setting whether command involves data transfer or not */
326 	if (cmd->data)
327 		cmd_reg |= MMCCMD_WDATX;
328 
329 	/* Setting whether stream or block transfer */
330 	if (cmd->flags & MMC_DATA_STREAM)
331 		cmd_reg |= MMCCMD_STRMTP;
332 
333 	/* Setting whether data read or write */
334 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE)
335 		cmd_reg |= MMCCMD_DTRW;
336 
337 	if (host->bus_mode == MMC_BUSMODE_PUSHPULL)
338 		cmd_reg |= MMCCMD_PPLEN;
339 
340 	/* set Command timeout */
341 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
342 
343 	/* Enable interrupt (calculate here, defer until FIFO is stuffed). */
344 	im_val =  MMCST0_RSPDNE | MMCST0_CRCRS | MMCST0_TOUTRS;
345 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
346 		im_val |= MMCST0_DATDNE | MMCST0_CRCWR;
347 
348 		if (!host->do_dma)
349 			im_val |= MMCST0_DXRDY;
350 	} else if (host->data_dir == DAVINCI_MMC_DATADIR_READ) {
351 		im_val |= MMCST0_DATDNE | MMCST0_CRCRD | MMCST0_TOUTRD;
352 
353 		if (!host->do_dma)
354 			im_val |= MMCST0_DRRDY;
355 	}
356 
357 	/*
358 	 * Before non-DMA WRITE commands the controller needs priming:
359 	 * FIFO should be populated with 32 bytes i.e. whatever is the FIFO size
360 	 */
361 	if (!host->do_dma && (host->data_dir == DAVINCI_MMC_DATADIR_WRITE))
362 		davinci_fifo_data_trans(host, rw_threshold);
363 
364 	writel(cmd->arg, host->base + DAVINCI_MMCARGHL);
365 	writel(cmd_reg,  host->base + DAVINCI_MMCCMD);
366 	writel(im_val, host->base + DAVINCI_MMCIM);
367 }
368 
369 /*----------------------------------------------------------------------*/
370 
371 /* DMA infrastructure */
372 
373 static void davinci_abort_dma(struct mmc_davinci_host *host)
374 {
375 	int sync_dev;
376 
377 	if (host->data_dir == DAVINCI_MMC_DATADIR_READ)
378 		sync_dev = host->rxdma;
379 	else
380 		sync_dev = host->txdma;
381 
382 	edma_stop(sync_dev);
383 	edma_clean_channel(sync_dev);
384 }
385 
386 static void
387 mmc_davinci_xfer_done(struct mmc_davinci_host *host, struct mmc_data *data);
388 
389 static void mmc_davinci_dma_cb(unsigned channel, u16 ch_status, void *data)
390 {
391 	if (DMA_COMPLETE != ch_status) {
392 		struct mmc_davinci_host *host = data;
393 
394 		/* Currently means:  DMA Event Missed, or "null" transfer
395 		 * request was seen.  In the future, TC errors (like bad
396 		 * addresses) might be presented too.
397 		 */
398 		dev_warn(mmc_dev(host->mmc), "DMA %s error\n",
399 			(host->data->flags & MMC_DATA_WRITE)
400 				? "write" : "read");
401 		host->data->error = -EIO;
402 		mmc_davinci_xfer_done(host, host->data);
403 	}
404 }
405 
406 /* Set up tx or rx template, to be modified and updated later */
407 static void __init mmc_davinci_dma_setup(struct mmc_davinci_host *host,
408 		bool tx, struct edmacc_param *template)
409 {
410 	unsigned	sync_dev;
411 	const u16	acnt = 4;
412 	const u16	bcnt = rw_threshold >> 2;
413 	const u16	ccnt = 0;
414 	u32		src_port = 0;
415 	u32		dst_port = 0;
416 	s16		src_bidx, dst_bidx;
417 	s16		src_cidx, dst_cidx;
418 
419 	/*
420 	 * A-B Sync transfer:  each DMA request is for one "frame" of
421 	 * rw_threshold bytes, broken into "acnt"-size chunks repeated
422 	 * "bcnt" times.  Each segment needs "ccnt" such frames; since
423 	 * we tell the block layer our mmc->max_seg_size limit, we can
424 	 * trust (later) that it's within bounds.
425 	 *
426 	 * The FIFOs are read/written in 4-byte chunks (acnt == 4) and
427 	 * EDMA will optimize memory operations to use larger bursts.
428 	 */
429 	if (tx) {
430 		sync_dev = host->txdma;
431 
432 		/* src_prt, ccnt, and link to be set up later */
433 		src_bidx = acnt;
434 		src_cidx = acnt * bcnt;
435 
436 		dst_port = host->mem_res->start + DAVINCI_MMCDXR;
437 		dst_bidx = 0;
438 		dst_cidx = 0;
439 	} else {
440 		sync_dev = host->rxdma;
441 
442 		src_port = host->mem_res->start + DAVINCI_MMCDRR;
443 		src_bidx = 0;
444 		src_cidx = 0;
445 
446 		/* dst_prt, ccnt, and link to be set up later */
447 		dst_bidx = acnt;
448 		dst_cidx = acnt * bcnt;
449 	}
450 
451 	/*
452 	 * We can't use FIFO mode for the FIFOs because MMC FIFO addresses
453 	 * are not 256-bit (32-byte) aligned.  So we use INCR, and the W8BIT
454 	 * parameter is ignored.
455 	 */
456 	edma_set_src(sync_dev, src_port, INCR, W8BIT);
457 	edma_set_dest(sync_dev, dst_port, INCR, W8BIT);
458 
459 	edma_set_src_index(sync_dev, src_bidx, src_cidx);
460 	edma_set_dest_index(sync_dev, dst_bidx, dst_cidx);
461 
462 	edma_set_transfer_params(sync_dev, acnt, bcnt, ccnt, 8, ABSYNC);
463 
464 	edma_read_slot(sync_dev, template);
465 
466 	/* don't bother with irqs or chaining */
467 	template->opt |= EDMA_CHAN_SLOT(sync_dev) << 12;
468 }
469 
470 static void mmc_davinci_send_dma_request(struct mmc_davinci_host *host,
471 		struct mmc_data *data)
472 {
473 	struct edmacc_param	*template;
474 	int			channel, slot;
475 	unsigned		link;
476 	struct scatterlist	*sg;
477 	unsigned		sg_len;
478 	unsigned		bytes_left = host->bytes_left;
479 	const unsigned		shift = ffs(rw_threshold) - 1;;
480 
481 	if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE) {
482 		template = &host->tx_template;
483 		channel = host->txdma;
484 	} else {
485 		template = &host->rx_template;
486 		channel = host->rxdma;
487 	}
488 
489 	/* We know sg_len and ccnt will never be out of range because
490 	 * we told the mmc layer which in turn tells the block layer
491 	 * to ensure that it only hands us one scatterlist segment
492 	 * per EDMA PARAM entry.  Update the PARAM
493 	 * entries needed for each segment of this scatterlist.
494 	 */
495 	for (slot = channel, link = 0, sg = data->sg, sg_len = host->sg_len;
496 			sg_len-- != 0 && bytes_left;
497 			sg = sg_next(sg), slot = host->links[link++]) {
498 		u32		buf = sg_dma_address(sg);
499 		unsigned	count = sg_dma_len(sg);
500 
501 		template->link_bcntrld = sg_len
502 				? (EDMA_CHAN_SLOT(host->links[link]) << 5)
503 				: 0xffff;
504 
505 		if (count > bytes_left)
506 			count = bytes_left;
507 		bytes_left -= count;
508 
509 		if (host->data_dir == DAVINCI_MMC_DATADIR_WRITE)
510 			template->src = buf;
511 		else
512 			template->dst = buf;
513 		template->ccnt = count >> shift;
514 
515 		edma_write_slot(slot, template);
516 	}
517 
518 	if (host->version == MMC_CTLR_VERSION_2)
519 		edma_clear_event(channel);
520 
521 	edma_start(channel);
522 }
523 
524 static int mmc_davinci_start_dma_transfer(struct mmc_davinci_host *host,
525 		struct mmc_data *data)
526 {
527 	int i;
528 	int mask = rw_threshold - 1;
529 
530 	host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
531 				((data->flags & MMC_DATA_WRITE)
532 				? DMA_TO_DEVICE
533 				: DMA_FROM_DEVICE));
534 
535 	/* no individual DMA segment should need a partial FIFO */
536 	for (i = 0; i < host->sg_len; i++) {
537 		if (sg_dma_len(data->sg + i) & mask) {
538 			dma_unmap_sg(mmc_dev(host->mmc),
539 					data->sg, data->sg_len,
540 					(data->flags & MMC_DATA_WRITE)
541 					? DMA_TO_DEVICE
542 					: DMA_FROM_DEVICE);
543 			return -1;
544 		}
545 	}
546 
547 	host->do_dma = 1;
548 	mmc_davinci_send_dma_request(host, data);
549 
550 	return 0;
551 }
552 
553 static void __init_or_module
554 davinci_release_dma_channels(struct mmc_davinci_host *host)
555 {
556 	unsigned	i;
557 
558 	if (!host->use_dma)
559 		return;
560 
561 	for (i = 0; i < host->n_link; i++)
562 		edma_free_slot(host->links[i]);
563 
564 	edma_free_channel(host->txdma);
565 	edma_free_channel(host->rxdma);
566 }
567 
568 static int __init davinci_acquire_dma_channels(struct mmc_davinci_host *host)
569 {
570 	int r, i;
571 
572 	/* Acquire master DMA write channel */
573 	r = edma_alloc_channel(host->txdma, mmc_davinci_dma_cb, host,
574 			EVENTQ_DEFAULT);
575 	if (r < 0) {
576 		dev_warn(mmc_dev(host->mmc), "alloc %s channel err %d\n",
577 				"tx", r);
578 		return r;
579 	}
580 	mmc_davinci_dma_setup(host, true, &host->tx_template);
581 
582 	/* Acquire master DMA read channel */
583 	r = edma_alloc_channel(host->rxdma, mmc_davinci_dma_cb, host,
584 			EVENTQ_DEFAULT);
585 	if (r < 0) {
586 		dev_warn(mmc_dev(host->mmc), "alloc %s channel err %d\n",
587 				"rx", r);
588 		goto free_master_write;
589 	}
590 	mmc_davinci_dma_setup(host, false, &host->rx_template);
591 
592 	/* Allocate parameter RAM slots, which will later be bound to a
593 	 * channel as needed to handle a scatterlist.
594 	 */
595 	for (i = 0; i < ARRAY_SIZE(host->links); i++) {
596 		r = edma_alloc_slot(EDMA_CTLR(host->txdma), EDMA_SLOT_ANY);
597 		if (r < 0) {
598 			dev_dbg(mmc_dev(host->mmc), "dma PaRAM alloc --> %d\n",
599 				r);
600 			break;
601 		}
602 		host->links[i] = r;
603 	}
604 	host->n_link = i;
605 
606 	return 0;
607 
608 free_master_write:
609 	edma_free_channel(host->txdma);
610 
611 	return r;
612 }
613 
614 /*----------------------------------------------------------------------*/
615 
616 static void
617 mmc_davinci_prepare_data(struct mmc_davinci_host *host, struct mmc_request *req)
618 {
619 	int fifo_lev = (rw_threshold == 32) ? MMCFIFOCTL_FIFOLEV : 0;
620 	int timeout;
621 	struct mmc_data *data = req->data;
622 
623 	if (host->version == MMC_CTLR_VERSION_2)
624 		fifo_lev = (rw_threshold == 64) ? MMCFIFOCTL_FIFOLEV : 0;
625 
626 	host->data = data;
627 	if (data == NULL) {
628 		host->data_dir = DAVINCI_MMC_DATADIR_NONE;
629 		writel(0, host->base + DAVINCI_MMCBLEN);
630 		writel(0, host->base + DAVINCI_MMCNBLK);
631 		return;
632 	}
633 
634 	dev_dbg(mmc_dev(host->mmc), "%s %s, %d blocks of %d bytes\n",
635 		(data->flags & MMC_DATA_STREAM) ? "stream" : "block",
636 		(data->flags & MMC_DATA_WRITE) ? "write" : "read",
637 		data->blocks, data->blksz);
638 	dev_dbg(mmc_dev(host->mmc), "  DTO %d cycles + %d ns\n",
639 		data->timeout_clks, data->timeout_ns);
640 	timeout = data->timeout_clks +
641 		(data->timeout_ns / host->ns_in_one_cycle);
642 	if (timeout > 0xffff)
643 		timeout = 0xffff;
644 
645 	writel(timeout, host->base + DAVINCI_MMCTOD);
646 	writel(data->blocks, host->base + DAVINCI_MMCNBLK);
647 	writel(data->blksz, host->base + DAVINCI_MMCBLEN);
648 
649 	/* Configure the FIFO */
650 	switch (data->flags & MMC_DATA_WRITE) {
651 	case MMC_DATA_WRITE:
652 		host->data_dir = DAVINCI_MMC_DATADIR_WRITE;
653 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_WR | MMCFIFOCTL_FIFORST,
654 			host->base + DAVINCI_MMCFIFOCTL);
655 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_WR,
656 			host->base + DAVINCI_MMCFIFOCTL);
657 		break;
658 
659 	default:
660 		host->data_dir = DAVINCI_MMC_DATADIR_READ;
661 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_RD | MMCFIFOCTL_FIFORST,
662 			host->base + DAVINCI_MMCFIFOCTL);
663 		writel(fifo_lev | MMCFIFOCTL_FIFODIR_RD,
664 			host->base + DAVINCI_MMCFIFOCTL);
665 		break;
666 	}
667 
668 	host->buffer = NULL;
669 	host->bytes_left = data->blocks * data->blksz;
670 
671 	/* For now we try to use DMA whenever we won't need partial FIFO
672 	 * reads or writes, either for the whole transfer (as tested here)
673 	 * or for any individual scatterlist segment (tested when we call
674 	 * start_dma_transfer).
675 	 *
676 	 * While we *could* change that, unusual block sizes are rarely
677 	 * used.  The occasional fallback to PIO should't hurt.
678 	 */
679 	if (host->use_dma && (host->bytes_left & (rw_threshold - 1)) == 0
680 			&& mmc_davinci_start_dma_transfer(host, data) == 0) {
681 		/* zero this to ensure we take no PIO paths */
682 		host->bytes_left = 0;
683 	} else {
684 		/* Revert to CPU Copy */
685 		host->sg_len = data->sg_len;
686 		host->sg = host->data->sg;
687 		mmc_davinci_sg_to_buf(host);
688 	}
689 }
690 
691 static void mmc_davinci_request(struct mmc_host *mmc, struct mmc_request *req)
692 {
693 	struct mmc_davinci_host *host = mmc_priv(mmc);
694 	unsigned long timeout = jiffies + msecs_to_jiffies(900);
695 	u32 mmcst1 = 0;
696 
697 	/* Card may still be sending BUSY after a previous operation,
698 	 * typically some kind of write.  If so, we can't proceed yet.
699 	 */
700 	while (time_before(jiffies, timeout)) {
701 		mmcst1  = readl(host->base + DAVINCI_MMCST1);
702 		if (!(mmcst1 & MMCST1_BUSY))
703 			break;
704 		cpu_relax();
705 	}
706 	if (mmcst1 & MMCST1_BUSY) {
707 		dev_err(mmc_dev(host->mmc), "still BUSY? bad ... \n");
708 		req->cmd->error = -ETIMEDOUT;
709 		mmc_request_done(mmc, req);
710 		return;
711 	}
712 
713 	host->do_dma = 0;
714 	mmc_davinci_prepare_data(host, req);
715 	mmc_davinci_start_command(host, req->cmd);
716 }
717 
718 static unsigned int calculate_freq_for_card(struct mmc_davinci_host *host,
719 	unsigned int mmc_req_freq)
720 {
721 	unsigned int mmc_freq = 0, mmc_pclk = 0, mmc_push_pull_divisor = 0;
722 
723 	mmc_pclk = host->mmc_input_clk;
724 	if (mmc_req_freq && mmc_pclk > (2 * mmc_req_freq))
725 		mmc_push_pull_divisor = ((unsigned int)mmc_pclk
726 				/ (2 * mmc_req_freq)) - 1;
727 	else
728 		mmc_push_pull_divisor = 0;
729 
730 	mmc_freq = (unsigned int)mmc_pclk
731 		/ (2 * (mmc_push_pull_divisor + 1));
732 
733 	if (mmc_freq > mmc_req_freq)
734 		mmc_push_pull_divisor = mmc_push_pull_divisor + 1;
735 	/* Convert ns to clock cycles */
736 	if (mmc_req_freq <= 400000)
737 		host->ns_in_one_cycle = (1000000) / (((mmc_pclk
738 				/ (2 * (mmc_push_pull_divisor + 1)))/1000));
739 	else
740 		host->ns_in_one_cycle = (1000000) / (((mmc_pclk
741 				/ (2 * (mmc_push_pull_divisor + 1)))/1000000));
742 
743 	return mmc_push_pull_divisor;
744 }
745 
746 static void calculate_clk_divider(struct mmc_host *mmc, struct mmc_ios *ios)
747 {
748 	unsigned int open_drain_freq = 0, mmc_pclk = 0;
749 	unsigned int mmc_push_pull_freq = 0;
750 	struct mmc_davinci_host *host = mmc_priv(mmc);
751 
752 	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN) {
753 		u32 temp;
754 
755 		/* Ignoring the init clock value passed for fixing the inter
756 		 * operability with different cards.
757 		 */
758 		open_drain_freq = ((unsigned int)mmc_pclk
759 				/ (2 * MMCSD_INIT_CLOCK)) - 1;
760 
761 		if (open_drain_freq > 0xFF)
762 			open_drain_freq = 0xFF;
763 
764 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKRT_MASK;
765 		temp |= open_drain_freq;
766 		writel(temp, host->base + DAVINCI_MMCCLK);
767 
768 		/* Convert ns to clock cycles */
769 		host->ns_in_one_cycle = (1000000) / (MMCSD_INIT_CLOCK/1000);
770 	} else {
771 		u32 temp;
772 		mmc_push_pull_freq = calculate_freq_for_card(host, ios->clock);
773 
774 		if (mmc_push_pull_freq > 0xFF)
775 			mmc_push_pull_freq = 0xFF;
776 
777 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKEN;
778 		writel(temp, host->base + DAVINCI_MMCCLK);
779 
780 		udelay(10);
781 
782 		temp = readl(host->base + DAVINCI_MMCCLK) & ~MMCCLK_CLKRT_MASK;
783 		temp |= mmc_push_pull_freq;
784 		writel(temp, host->base + DAVINCI_MMCCLK);
785 
786 		writel(temp | MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
787 
788 		udelay(10);
789 	}
790 }
791 
792 static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
793 {
794 	unsigned int mmc_pclk = 0;
795 	struct mmc_davinci_host *host = mmc_priv(mmc);
796 
797 	mmc_pclk = host->mmc_input_clk;
798 	dev_dbg(mmc_dev(host->mmc),
799 		"clock %dHz busmode %d powermode %d Vdd %04x\n",
800 		ios->clock, ios->bus_mode, ios->power_mode,
801 		ios->vdd);
802 	if (ios->bus_width == MMC_BUS_WIDTH_4) {
803 		dev_dbg(mmc_dev(host->mmc), "Enabling 4 bit mode\n");
804 		writel(readl(host->base + DAVINCI_MMCCTL) | MMCCTL_WIDTH_4_BIT,
805 			host->base + DAVINCI_MMCCTL);
806 	} else {
807 		dev_dbg(mmc_dev(host->mmc), "Disabling 4 bit mode\n");
808 		writel(readl(host->base + DAVINCI_MMCCTL) & ~MMCCTL_WIDTH_4_BIT,
809 			host->base + DAVINCI_MMCCTL);
810 	}
811 
812 	calculate_clk_divider(mmc, ios);
813 
814 	host->bus_mode = ios->bus_mode;
815 	if (ios->power_mode == MMC_POWER_UP) {
816 		unsigned long timeout = jiffies + msecs_to_jiffies(50);
817 		bool lose = true;
818 
819 		/* Send clock cycles, poll completion */
820 		writel(0, host->base + DAVINCI_MMCARGHL);
821 		writel(MMCCMD_INITCK, host->base + DAVINCI_MMCCMD);
822 		while (time_before(jiffies, timeout)) {
823 			u32 tmp = readl(host->base + DAVINCI_MMCST0);
824 
825 			if (tmp & MMCST0_RSPDNE) {
826 				lose = false;
827 				break;
828 			}
829 			cpu_relax();
830 		}
831 		if (lose)
832 			dev_warn(mmc_dev(host->mmc), "powerup timeout\n");
833 	}
834 
835 	/* FIXME on power OFF, reset things ... */
836 }
837 
838 static void
839 mmc_davinci_xfer_done(struct mmc_davinci_host *host, struct mmc_data *data)
840 {
841 	host->data = NULL;
842 
843 	if (host->do_dma) {
844 		davinci_abort_dma(host);
845 
846 		dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
847 			     (data->flags & MMC_DATA_WRITE)
848 			     ? DMA_TO_DEVICE
849 			     : DMA_FROM_DEVICE);
850 		host->do_dma = false;
851 	}
852 	host->data_dir = DAVINCI_MMC_DATADIR_NONE;
853 
854 	if (!data->stop || (host->cmd && host->cmd->error)) {
855 		mmc_request_done(host->mmc, data->mrq);
856 		writel(0, host->base + DAVINCI_MMCIM);
857 	} else
858 		mmc_davinci_start_command(host, data->stop);
859 }
860 
861 static void mmc_davinci_cmd_done(struct mmc_davinci_host *host,
862 				 struct mmc_command *cmd)
863 {
864 	host->cmd = NULL;
865 
866 	if (cmd->flags & MMC_RSP_PRESENT) {
867 		if (cmd->flags & MMC_RSP_136) {
868 			/* response type 2 */
869 			cmd->resp[3] = readl(host->base + DAVINCI_MMCRSP01);
870 			cmd->resp[2] = readl(host->base + DAVINCI_MMCRSP23);
871 			cmd->resp[1] = readl(host->base + DAVINCI_MMCRSP45);
872 			cmd->resp[0] = readl(host->base + DAVINCI_MMCRSP67);
873 		} else {
874 			/* response types 1, 1b, 3, 4, 5, 6 */
875 			cmd->resp[0] = readl(host->base + DAVINCI_MMCRSP67);
876 		}
877 	}
878 
879 	if (host->data == NULL || cmd->error) {
880 		if (cmd->error == -ETIMEDOUT)
881 			cmd->mrq->cmd->retries = 0;
882 		mmc_request_done(host->mmc, cmd->mrq);
883 		writel(0, host->base + DAVINCI_MMCIM);
884 	}
885 }
886 
887 static void
888 davinci_abort_data(struct mmc_davinci_host *host, struct mmc_data *data)
889 {
890 	u32 temp;
891 
892 	/* reset command and data state machines */
893 	temp = readl(host->base + DAVINCI_MMCCTL);
894 	writel(temp | MMCCTL_CMDRST | MMCCTL_DATRST,
895 		host->base + DAVINCI_MMCCTL);
896 
897 	temp &= ~(MMCCTL_CMDRST | MMCCTL_DATRST);
898 	udelay(10);
899 	writel(temp, host->base + DAVINCI_MMCCTL);
900 }
901 
902 static irqreturn_t mmc_davinci_irq(int irq, void *dev_id)
903 {
904 	struct mmc_davinci_host *host = (struct mmc_davinci_host *)dev_id;
905 	unsigned int status, qstatus;
906 	int end_command = 0;
907 	int end_transfer = 0;
908 	struct mmc_data *data = host->data;
909 
910 	if (host->cmd == NULL && host->data == NULL) {
911 		status = readl(host->base + DAVINCI_MMCST0);
912 		dev_dbg(mmc_dev(host->mmc),
913 			"Spurious interrupt 0x%04x\n", status);
914 		/* Disable the interrupt from mmcsd */
915 		writel(0, host->base + DAVINCI_MMCIM);
916 		return IRQ_NONE;
917 	}
918 
919 	status = readl(host->base + DAVINCI_MMCST0);
920 	qstatus = status;
921 
922 	/* handle FIFO first when using PIO for data.
923 	 * bytes_left will decrease to zero as I/O progress and status will
924 	 * read zero over iteration because this controller status
925 	 * register(MMCST0) reports any status only once and it is cleared
926 	 * by read. So, it is not unbouned loop even in the case of
927 	 * non-dma.
928 	 */
929 	while (host->bytes_left && (status & (MMCST0_DXRDY | MMCST0_DRRDY))) {
930 		davinci_fifo_data_trans(host, rw_threshold);
931 		status = readl(host->base + DAVINCI_MMCST0);
932 		if (!status)
933 			break;
934 		qstatus |= status;
935 	}
936 
937 	if (qstatus & MMCST0_DATDNE) {
938 		/* All blocks sent/received, and CRC checks passed */
939 		if (data != NULL) {
940 			if ((host->do_dma == 0) && (host->bytes_left > 0)) {
941 				/* if datasize < rw_threshold
942 				 * no RX ints are generated
943 				 */
944 				davinci_fifo_data_trans(host, host->bytes_left);
945 			}
946 			end_transfer = 1;
947 			data->bytes_xfered = data->blocks * data->blksz;
948 		} else {
949 			dev_err(mmc_dev(host->mmc),
950 					"DATDNE with no host->data\n");
951 		}
952 	}
953 
954 	if (qstatus & MMCST0_TOUTRD) {
955 		/* Read data timeout */
956 		data->error = -ETIMEDOUT;
957 		end_transfer = 1;
958 
959 		dev_dbg(mmc_dev(host->mmc),
960 			"read data timeout, status %x\n",
961 			qstatus);
962 
963 		davinci_abort_data(host, data);
964 	}
965 
966 	if (qstatus & (MMCST0_CRCWR | MMCST0_CRCRD)) {
967 		/* Data CRC error */
968 		data->error = -EILSEQ;
969 		end_transfer = 1;
970 
971 		/* NOTE:  this controller uses CRCWR to report both CRC
972 		 * errors and timeouts (on writes).  MMCDRSP values are
973 		 * only weakly documented, but 0x9f was clearly a timeout
974 		 * case and the two three-bit patterns in various SD specs
975 		 * (101, 010) aren't part of it ...
976 		 */
977 		if (qstatus & MMCST0_CRCWR) {
978 			u32 temp = readb(host->base + DAVINCI_MMCDRSP);
979 
980 			if (temp == 0x9f)
981 				data->error = -ETIMEDOUT;
982 		}
983 		dev_dbg(mmc_dev(host->mmc), "data %s %s error\n",
984 			(qstatus & MMCST0_CRCWR) ? "write" : "read",
985 			(data->error == -ETIMEDOUT) ? "timeout" : "CRC");
986 
987 		davinci_abort_data(host, data);
988 	}
989 
990 	if (qstatus & MMCST0_TOUTRS) {
991 		/* Command timeout */
992 		if (host->cmd) {
993 			dev_dbg(mmc_dev(host->mmc),
994 				"CMD%d timeout, status %x\n",
995 				host->cmd->opcode, qstatus);
996 			host->cmd->error = -ETIMEDOUT;
997 			if (data) {
998 				end_transfer = 1;
999 				davinci_abort_data(host, data);
1000 			} else
1001 				end_command = 1;
1002 		}
1003 	}
1004 
1005 	if (qstatus & MMCST0_CRCRS) {
1006 		/* Command CRC error */
1007 		dev_dbg(mmc_dev(host->mmc), "Command CRC error\n");
1008 		if (host->cmd) {
1009 			host->cmd->error = -EILSEQ;
1010 			end_command = 1;
1011 		}
1012 	}
1013 
1014 	if (qstatus & MMCST0_RSPDNE) {
1015 		/* End of command phase */
1016 		end_command = (int) host->cmd;
1017 	}
1018 
1019 	if (end_command)
1020 		mmc_davinci_cmd_done(host, host->cmd);
1021 	if (end_transfer)
1022 		mmc_davinci_xfer_done(host, data);
1023 	return IRQ_HANDLED;
1024 }
1025 
1026 static int mmc_davinci_get_cd(struct mmc_host *mmc)
1027 {
1028 	struct platform_device *pdev = to_platform_device(mmc->parent);
1029 	struct davinci_mmc_config *config = pdev->dev.platform_data;
1030 
1031 	if (!config || !config->get_cd)
1032 		return -ENOSYS;
1033 	return config->get_cd(pdev->id);
1034 }
1035 
1036 static int mmc_davinci_get_ro(struct mmc_host *mmc)
1037 {
1038 	struct platform_device *pdev = to_platform_device(mmc->parent);
1039 	struct davinci_mmc_config *config = pdev->dev.platform_data;
1040 
1041 	if (!config || !config->get_ro)
1042 		return -ENOSYS;
1043 	return config->get_ro(pdev->id);
1044 }
1045 
1046 static struct mmc_host_ops mmc_davinci_ops = {
1047 	.request	= mmc_davinci_request,
1048 	.set_ios	= mmc_davinci_set_ios,
1049 	.get_cd		= mmc_davinci_get_cd,
1050 	.get_ro		= mmc_davinci_get_ro,
1051 };
1052 
1053 /*----------------------------------------------------------------------*/
1054 
1055 #ifdef CONFIG_CPU_FREQ
1056 static int mmc_davinci_cpufreq_transition(struct notifier_block *nb,
1057 				     unsigned long val, void *data)
1058 {
1059 	struct mmc_davinci_host *host;
1060 	unsigned int mmc_pclk;
1061 	struct mmc_host *mmc;
1062 	unsigned long flags;
1063 
1064 	host = container_of(nb, struct mmc_davinci_host, freq_transition);
1065 	mmc = host->mmc;
1066 	mmc_pclk = clk_get_rate(host->clk);
1067 
1068 	if (val == CPUFREQ_POSTCHANGE) {
1069 		spin_lock_irqsave(&mmc->lock, flags);
1070 		host->mmc_input_clk = mmc_pclk;
1071 		calculate_clk_divider(mmc, &mmc->ios);
1072 		spin_unlock_irqrestore(&mmc->lock, flags);
1073 	}
1074 
1075 	return 0;
1076 }
1077 
1078 static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host)
1079 {
1080 	host->freq_transition.notifier_call = mmc_davinci_cpufreq_transition;
1081 
1082 	return cpufreq_register_notifier(&host->freq_transition,
1083 					 CPUFREQ_TRANSITION_NOTIFIER);
1084 }
1085 
1086 static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host)
1087 {
1088 	cpufreq_unregister_notifier(&host->freq_transition,
1089 				    CPUFREQ_TRANSITION_NOTIFIER);
1090 }
1091 #else
1092 static inline int mmc_davinci_cpufreq_register(struct mmc_davinci_host *host)
1093 {
1094 	return 0;
1095 }
1096 
1097 static inline void mmc_davinci_cpufreq_deregister(struct mmc_davinci_host *host)
1098 {
1099 }
1100 #endif
1101 static void __init init_mmcsd_host(struct mmc_davinci_host *host)
1102 {
1103 	/* DAT line portion is diabled and in reset state */
1104 	writel(readl(host->base + DAVINCI_MMCCTL) | MMCCTL_DATRST,
1105 		host->base + DAVINCI_MMCCTL);
1106 
1107 	/* CMD line portion is diabled and in reset state */
1108 	writel(readl(host->base + DAVINCI_MMCCTL) | MMCCTL_CMDRST,
1109 		host->base + DAVINCI_MMCCTL);
1110 
1111 	udelay(10);
1112 
1113 	writel(0, host->base + DAVINCI_MMCCLK);
1114 	writel(MMCCLK_CLKEN, host->base + DAVINCI_MMCCLK);
1115 
1116 	writel(0x1FFF, host->base + DAVINCI_MMCTOR);
1117 	writel(0xFFFF, host->base + DAVINCI_MMCTOD);
1118 
1119 	writel(readl(host->base + DAVINCI_MMCCTL) & ~MMCCTL_DATRST,
1120 		host->base + DAVINCI_MMCCTL);
1121 	writel(readl(host->base + DAVINCI_MMCCTL) & ~MMCCTL_CMDRST,
1122 		host->base + DAVINCI_MMCCTL);
1123 
1124 	udelay(10);
1125 }
1126 
1127 static int __init davinci_mmcsd_probe(struct platform_device *pdev)
1128 {
1129 	struct davinci_mmc_config *pdata = pdev->dev.platform_data;
1130 	struct mmc_davinci_host *host = NULL;
1131 	struct mmc_host *mmc = NULL;
1132 	struct resource *r, *mem = NULL;
1133 	int ret = 0, irq = 0;
1134 	size_t mem_size;
1135 
1136 	/* REVISIT:  when we're fully converted, fail if pdata is NULL */
1137 
1138 	ret = -ENODEV;
1139 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1140 	irq = platform_get_irq(pdev, 0);
1141 	if (!r || irq == NO_IRQ)
1142 		goto out;
1143 
1144 	ret = -EBUSY;
1145 	mem_size = resource_size(r);
1146 	mem = request_mem_region(r->start, mem_size, pdev->name);
1147 	if (!mem)
1148 		goto out;
1149 
1150 	ret = -ENOMEM;
1151 	mmc = mmc_alloc_host(sizeof(struct mmc_davinci_host), &pdev->dev);
1152 	if (!mmc)
1153 		goto out;
1154 
1155 	host = mmc_priv(mmc);
1156 	host->mmc = mmc;	/* Important */
1157 
1158 	r = platform_get_resource(pdev, IORESOURCE_DMA, 0);
1159 	if (!r)
1160 		goto out;
1161 	host->rxdma = r->start;
1162 
1163 	r = platform_get_resource(pdev, IORESOURCE_DMA, 1);
1164 	if (!r)
1165 		goto out;
1166 	host->txdma = r->start;
1167 
1168 	host->mem_res = mem;
1169 	host->base = ioremap(mem->start, mem_size);
1170 	if (!host->base)
1171 		goto out;
1172 
1173 	ret = -ENXIO;
1174 	host->clk = clk_get(&pdev->dev, "MMCSDCLK");
1175 	if (IS_ERR(host->clk)) {
1176 		ret = PTR_ERR(host->clk);
1177 		goto out;
1178 	}
1179 	clk_enable(host->clk);
1180 	host->mmc_input_clk = clk_get_rate(host->clk);
1181 
1182 	init_mmcsd_host(host);
1183 
1184 	host->use_dma = use_dma;
1185 	host->irq = irq;
1186 
1187 	if (host->use_dma && davinci_acquire_dma_channels(host) != 0)
1188 		host->use_dma = 0;
1189 
1190 	/* REVISIT:  someday, support IRQ-driven card detection.  */
1191 	mmc->caps |= MMC_CAP_NEEDS_POLL;
1192 
1193 	if (!pdata || pdata->wires == 4 || pdata->wires == 0)
1194 		mmc->caps |= MMC_CAP_4_BIT_DATA;
1195 
1196 	host->version = pdata->version;
1197 
1198 	mmc->ops = &mmc_davinci_ops;
1199 	mmc->f_min = 312500;
1200 	mmc->f_max = 25000000;
1201 	if (pdata && pdata->max_freq)
1202 		mmc->f_max = pdata->max_freq;
1203 	if (pdata && pdata->caps)
1204 		mmc->caps |= pdata->caps;
1205 	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
1206 
1207 	/* With no iommu coalescing pages, each phys_seg is a hw_seg.
1208 	 * Each hw_seg uses one EDMA parameter RAM slot, always one
1209 	 * channel and then usually some linked slots.
1210 	 */
1211 	mmc->max_hw_segs	= 1 + host->n_link;
1212 	mmc->max_phys_segs	= mmc->max_hw_segs;
1213 
1214 	/* EDMA limit per hw segment (one or two MBytes) */
1215 	mmc->max_seg_size	= MAX_CCNT * rw_threshold;
1216 
1217 	/* MMC/SD controller limits for multiblock requests */
1218 	mmc->max_blk_size	= 4095;  /* BLEN is 12 bits */
1219 	mmc->max_blk_count	= 65535; /* NBLK is 16 bits */
1220 	mmc->max_req_size	= mmc->max_blk_size * mmc->max_blk_count;
1221 
1222 	dev_dbg(mmc_dev(host->mmc), "max_phys_segs=%d\n", mmc->max_phys_segs);
1223 	dev_dbg(mmc_dev(host->mmc), "max_hw_segs=%d\n", mmc->max_hw_segs);
1224 	dev_dbg(mmc_dev(host->mmc), "max_blk_size=%d\n", mmc->max_blk_size);
1225 	dev_dbg(mmc_dev(host->mmc), "max_req_size=%d\n", mmc->max_req_size);
1226 	dev_dbg(mmc_dev(host->mmc), "max_seg_size=%d\n", mmc->max_seg_size);
1227 
1228 	platform_set_drvdata(pdev, host);
1229 
1230 	ret = mmc_davinci_cpufreq_register(host);
1231 	if (ret) {
1232 		dev_err(&pdev->dev, "failed to register cpufreq\n");
1233 		goto cpu_freq_fail;
1234 	}
1235 
1236 	ret = mmc_add_host(mmc);
1237 	if (ret < 0)
1238 		goto out;
1239 
1240 	ret = request_irq(irq, mmc_davinci_irq, 0, mmc_hostname(mmc), host);
1241 	if (ret)
1242 		goto out;
1243 
1244 	rename_region(mem, mmc_hostname(mmc));
1245 
1246 	dev_info(mmc_dev(host->mmc), "Using %s, %d-bit mode\n",
1247 		host->use_dma ? "DMA" : "PIO",
1248 		(mmc->caps & MMC_CAP_4_BIT_DATA) ? 4 : 1);
1249 
1250 	return 0;
1251 
1252 out:
1253 	mmc_davinci_cpufreq_deregister(host);
1254 cpu_freq_fail:
1255 	if (host) {
1256 		davinci_release_dma_channels(host);
1257 
1258 		if (host->clk) {
1259 			clk_disable(host->clk);
1260 			clk_put(host->clk);
1261 		}
1262 
1263 		if (host->base)
1264 			iounmap(host->base);
1265 	}
1266 
1267 	if (mmc)
1268 		mmc_free_host(mmc);
1269 
1270 	if (mem)
1271 		release_resource(mem);
1272 
1273 	dev_dbg(&pdev->dev, "probe err %d\n", ret);
1274 
1275 	return ret;
1276 }
1277 
1278 static int __exit davinci_mmcsd_remove(struct platform_device *pdev)
1279 {
1280 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1281 
1282 	platform_set_drvdata(pdev, NULL);
1283 	if (host) {
1284 		mmc_davinci_cpufreq_deregister(host);
1285 
1286 		mmc_remove_host(host->mmc);
1287 		free_irq(host->irq, host);
1288 
1289 		davinci_release_dma_channels(host);
1290 
1291 		clk_disable(host->clk);
1292 		clk_put(host->clk);
1293 
1294 		iounmap(host->base);
1295 
1296 		release_resource(host->mem_res);
1297 
1298 		mmc_free_host(host->mmc);
1299 	}
1300 
1301 	return 0;
1302 }
1303 
1304 #ifdef CONFIG_PM
1305 static int davinci_mmcsd_suspend(struct platform_device *pdev, pm_message_t msg)
1306 {
1307 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1308 
1309 	return mmc_suspend_host(host->mmc, msg);
1310 }
1311 
1312 static int davinci_mmcsd_resume(struct platform_device *pdev)
1313 {
1314 	struct mmc_davinci_host *host = platform_get_drvdata(pdev);
1315 
1316 	return mmc_resume_host(host->mmc);
1317 }
1318 #else
1319 #define davinci_mmcsd_suspend	NULL
1320 #define davinci_mmcsd_resume	NULL
1321 #endif
1322 
1323 static struct platform_driver davinci_mmcsd_driver = {
1324 	.driver		= {
1325 		.name	= "davinci_mmc",
1326 		.owner	= THIS_MODULE,
1327 	},
1328 	.remove		= __exit_p(davinci_mmcsd_remove),
1329 	.suspend	= davinci_mmcsd_suspend,
1330 	.resume		= davinci_mmcsd_resume,
1331 };
1332 
1333 static int __init davinci_mmcsd_init(void)
1334 {
1335 	return platform_driver_probe(&davinci_mmcsd_driver,
1336 				     davinci_mmcsd_probe);
1337 }
1338 module_init(davinci_mmcsd_init);
1339 
1340 static void __exit davinci_mmcsd_exit(void)
1341 {
1342 	platform_driver_unregister(&davinci_mmcsd_driver);
1343 }
1344 module_exit(davinci_mmcsd_exit);
1345 
1346 MODULE_AUTHOR("Texas Instruments India");
1347 MODULE_LICENSE("GPL");
1348 MODULE_DESCRIPTION("MMC/SD driver for Davinci MMC controller");
1349 
1350