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1/*
2 * MOXA ART MMC host driver.
3 *
4 * Copyright (C) 2014 Jonas Jensen
5 *
6 * Jonas Jensen <jonas.jensen@gmail.com>
7 *
8 * Based on code from
9 * Moxa Technologies Co., Ltd. <www.moxa.com>
10 *
11 * This file is licensed under the terms of the GNU General Public
12 * License version 2. This program is licensed "as is" without any
13 * warranty of any kind, whether express or implied.
14 */
15
16#include <linux/module.h>
17#include <linux/init.h>
18#include <linux/platform_device.h>
19#include <linux/delay.h>
20#include <linux/errno.h>
21#include <linux/interrupt.h>
22#include <linux/blkdev.h>
23#include <linux/dma-mapping.h>
24#include <linux/dmaengine.h>
25#include <linux/mmc/host.h>
26#include <linux/mmc/sd.h>
27#include <linux/sched.h>
28#include <linux/io.h>
29#include <linux/of_address.h>
30#include <linux/of_irq.h>
31#include <linux/clk.h>
32#include <linux/bitops.h>
33#include <linux/of_dma.h>
34#include <linux/spinlock.h>
35
36#define REG_COMMAND 0
37#define REG_ARGUMENT 4
38#define REG_RESPONSE0 8
39#define REG_RESPONSE1 12
40#define REG_RESPONSE2 16
41#define REG_RESPONSE3 20
42#define REG_RESPONSE_COMMAND 24
43#define REG_DATA_CONTROL 28
44#define REG_DATA_TIMER 32
45#define REG_DATA_LENGTH 36
46#define REG_STATUS 40
47#define REG_CLEAR 44
48#define REG_INTERRUPT_MASK 48
49#define REG_POWER_CONTROL 52
50#define REG_CLOCK_CONTROL 56
51#define REG_BUS_WIDTH 60
52#define REG_DATA_WINDOW 64
53#define REG_FEATURE 68
54#define REG_REVISION 72
55
56/* REG_COMMAND */
57#define CMD_SDC_RESET BIT(10)
58#define CMD_EN BIT(9)
59#define CMD_APP_CMD BIT(8)
60#define CMD_LONG_RSP BIT(7)
61#define CMD_NEED_RSP BIT(6)
62#define CMD_IDX_MASK 0x3f
63
64/* REG_RESPONSE_COMMAND */
65#define RSP_CMD_APP BIT(6)
66#define RSP_CMD_IDX_MASK 0x3f
67
68/* REG_DATA_CONTROL */
69#define DCR_DATA_FIFO_RESET BIT(8)
70#define DCR_DATA_THRES BIT(7)
71#define DCR_DATA_EN BIT(6)
72#define DCR_DMA_EN BIT(5)
73#define DCR_DATA_WRITE BIT(4)
74#define DCR_BLK_SIZE 0x0f
75
76/* REG_DATA_LENGTH */
77#define DATA_LEN_MASK 0xffffff
78
79/* REG_STATUS */
80#define WRITE_PROT BIT(12)
81#define CARD_DETECT BIT(11)
82/* 1-10 below can be sent to either registers, interrupt or clear. */
83#define CARD_CHANGE BIT(10)
84#define FIFO_ORUN BIT(9)
85#define FIFO_URUN BIT(8)
86#define DATA_END BIT(7)
87#define CMD_SENT BIT(6)
88#define DATA_CRC_OK BIT(5)
89#define RSP_CRC_OK BIT(4)
90#define DATA_TIMEOUT BIT(3)
91#define RSP_TIMEOUT BIT(2)
92#define DATA_CRC_FAIL BIT(1)
93#define RSP_CRC_FAIL BIT(0)
94
95#define MASK_RSP (RSP_TIMEOUT | RSP_CRC_FAIL | \
96 RSP_CRC_OK | CARD_DETECT | CMD_SENT)
97
98#define MASK_DATA (DATA_CRC_OK | DATA_END | \
99 DATA_CRC_FAIL | DATA_TIMEOUT)
100
101#define MASK_INTR_PIO (FIFO_URUN | FIFO_ORUN | CARD_CHANGE)
102
103/* REG_POWER_CONTROL */
104#define SD_POWER_ON BIT(4)
105#define SD_POWER_MASK 0x0f
106
107/* REG_CLOCK_CONTROL */
108#define CLK_HISPD BIT(9)
109#define CLK_OFF BIT(8)
110#define CLK_SD BIT(7)
111#define CLK_DIV_MASK 0x7f
112
113/* REG_BUS_WIDTH */
114#define BUS_WIDTH_4_SUPPORT BIT(3)
115#define BUS_WIDTH_4 BIT(2)
116#define BUS_WIDTH_1 BIT(0)
117
118#define MMC_VDD_360 23
119#define MIN_POWER (MMC_VDD_360 - SD_POWER_MASK)
120#define MAX_RETRIES 500000
121
122struct moxart_host {
123 spinlock_t lock;
124
125 void __iomem *base;
126
127 phys_addr_t reg_phys;
128
129 struct dma_chan *dma_chan_tx;
130 struct dma_chan *dma_chan_rx;
131 struct dma_async_tx_descriptor *tx_desc;
132 struct mmc_host *mmc;
133 struct mmc_request *mrq;
134 struct scatterlist *cur_sg;
135 struct completion dma_complete;
136 struct completion pio_complete;
137
138 u32 num_sg;
139 u32 data_remain;
140 u32 data_len;
141 u32 fifo_width;
142 u32 timeout;
143 u32 rate;
144
145 long sysclk;
146
147 bool have_dma;
148 bool is_removed;
149};
150
151static inline void moxart_init_sg(struct moxart_host *host,
152 struct mmc_data *data)
153{
154 host->cur_sg = data->sg;
155 host->num_sg = data->sg_len;
156 host->data_remain = host->cur_sg->length;
157
158 if (host->data_remain > host->data_len)
159 host->data_remain = host->data_len;
160}
161
162static inline int moxart_next_sg(struct moxart_host *host)
163{
164 int remain;
165 struct mmc_data *data = host->mrq->cmd->data;
166
167 host->cur_sg++;
168 host->num_sg--;
169
170 if (host->num_sg > 0) {
171 host->data_remain = host->cur_sg->length;
172 remain = host->data_len - data->bytes_xfered;
173 if (remain > 0 && remain < host->data_remain)
174 host->data_remain = remain;
175 }
176
177 return host->num_sg;
178}
179
180static int moxart_wait_for_status(struct moxart_host *host,
181 u32 mask, u32 *status)
182{
183 int ret = -ETIMEDOUT;
184 u32 i;
185
186 for (i = 0; i < MAX_RETRIES; i++) {
187 *status = readl(host->base + REG_STATUS);
188 if (!(*status & mask)) {
189 udelay(5);
190 continue;
191 }
192 writel(*status & mask, host->base + REG_CLEAR);
193 ret = 0;
194 break;
195 }
196
197 if (ret)
198 dev_err(mmc_dev(host->mmc), "timed out waiting for status\n");
199
200 return ret;
201}
202
203
204static void moxart_send_command(struct moxart_host *host,
205 struct mmc_command *cmd)
206{
207 u32 status, cmdctrl;
208
209 writel(RSP_TIMEOUT | RSP_CRC_OK |
210 RSP_CRC_FAIL | CMD_SENT, host->base + REG_CLEAR);
211 writel(cmd->arg, host->base + REG_ARGUMENT);
212
213 cmdctrl = cmd->opcode & CMD_IDX_MASK;
214 if (cmdctrl == SD_APP_SET_BUS_WIDTH || cmdctrl == SD_APP_OP_COND ||
215 cmdctrl == SD_APP_SEND_SCR || cmdctrl == SD_APP_SD_STATUS ||
216 cmdctrl == SD_APP_SEND_NUM_WR_BLKS)
217 cmdctrl |= CMD_APP_CMD;
218
219 if (cmd->flags & MMC_RSP_PRESENT)
220 cmdctrl |= CMD_NEED_RSP;
221
222 if (cmd->flags & MMC_RSP_136)
223 cmdctrl |= CMD_LONG_RSP;
224
225 writel(cmdctrl | CMD_EN, host->base + REG_COMMAND);
226
227 if (moxart_wait_for_status(host, MASK_RSP, &status) == -ETIMEDOUT)
228 cmd->error = -ETIMEDOUT;
229
230 if (status & RSP_TIMEOUT) {
231 cmd->error = -ETIMEDOUT;
232 return;
233 }
234 if (status & RSP_CRC_FAIL) {
235 cmd->error = -EIO;
236 return;
237 }
238 if (status & RSP_CRC_OK) {
239 if (cmd->flags & MMC_RSP_136) {
240 cmd->resp[3] = readl(host->base + REG_RESPONSE0);
241 cmd->resp[2] = readl(host->base + REG_RESPONSE1);
242 cmd->resp[1] = readl(host->base + REG_RESPONSE2);
243 cmd->resp[0] = readl(host->base + REG_RESPONSE3);
244 } else {
245 cmd->resp[0] = readl(host->base + REG_RESPONSE0);
246 }
247 }
248}
249
250static void moxart_dma_complete(void *param)
251{
252 struct moxart_host *host = param;
253
254 complete(&host->dma_complete);
255}
256
257static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
258{
259 u32 len, dir_slave;
260 struct dma_async_tx_descriptor *desc = NULL;
261 struct dma_chan *dma_chan;
262
263 if (host->data_len == data->bytes_xfered)
264 return;
265
266 if (data->flags & MMC_DATA_WRITE) {
267 dma_chan = host->dma_chan_tx;
268 dir_slave = DMA_MEM_TO_DEV;
269 } else {
270 dma_chan = host->dma_chan_rx;
271 dir_slave = DMA_DEV_TO_MEM;
272 }
273
274 len = dma_map_sg(dma_chan->device->dev, data->sg,
275 data->sg_len, mmc_get_dma_dir(data));
276
277 if (len > 0) {
278 desc = dmaengine_prep_slave_sg(dma_chan, data->sg,
279 len, dir_slave,
280 DMA_PREP_INTERRUPT |
281 DMA_CTRL_ACK);
282 } else {
283 dev_err(mmc_dev(host->mmc), "dma_map_sg returned zero length\n");
284 }
285
286 if (desc) {
287 host->tx_desc = desc;
288 desc->callback = moxart_dma_complete;
289 desc->callback_param = host;
290 dmaengine_submit(desc);
291 dma_async_issue_pending(dma_chan);
292 }
293
294 data->bytes_xfered += host->data_remain;
295
296 wait_for_completion_interruptible_timeout(&host->dma_complete,
297 host->timeout);
298
299 dma_unmap_sg(dma_chan->device->dev,
300 data->sg, data->sg_len,
301 mmc_get_dma_dir(data));
302}
303
304
305static void moxart_transfer_pio(struct moxart_host *host)
306{
307 struct mmc_data *data = host->mrq->cmd->data;
308 u32 *sgp, len = 0, remain, status;
309
310 if (host->data_len == data->bytes_xfered)
311 return;
312
313 sgp = sg_virt(host->cur_sg);
314 remain = host->data_remain;
315
316 if (data->flags & MMC_DATA_WRITE) {
317 while (remain > 0) {
318 if (moxart_wait_for_status(host, FIFO_URUN, &status)
319 == -ETIMEDOUT) {
320 data->error = -ETIMEDOUT;
321 complete(&host->pio_complete);
322 return;
323 }
324 for (len = 0; len < remain && len < host->fifo_width;) {
325 iowrite32(*sgp, host->base + REG_DATA_WINDOW);
326 sgp++;
327 len += 4;
328 }
329 remain -= len;
330 }
331
332 } else {
333 while (remain > 0) {
334 if (moxart_wait_for_status(host, FIFO_ORUN, &status)
335 == -ETIMEDOUT) {
336 data->error = -ETIMEDOUT;
337 complete(&host->pio_complete);
338 return;
339 }
340 for (len = 0; len < remain && len < host->fifo_width;) {
341 /* SCR data must be read in big endian. */
342 if (data->mrq->cmd->opcode == SD_APP_SEND_SCR)
343 *sgp = ioread32be(host->base +
344 REG_DATA_WINDOW);
345 else
346 *sgp = ioread32(host->base +
347 REG_DATA_WINDOW);
348 sgp++;
349 len += 4;
350 }
351 remain -= len;
352 }
353 }
354
355 data->bytes_xfered += host->data_remain - remain;
356 host->data_remain = remain;
357
358 if (host->data_len != data->bytes_xfered)
359 moxart_next_sg(host);
360 else
361 complete(&host->pio_complete);
362}
363
364static void moxart_prepare_data(struct moxart_host *host)
365{
366 struct mmc_data *data = host->mrq->cmd->data;
367 u32 datactrl;
368 int blksz_bits;
369
370 if (!data)
371 return;
372
373 host->data_len = data->blocks * data->blksz;
374 blksz_bits = ffs(data->blksz) - 1;
375 BUG_ON(1 << blksz_bits != data->blksz);
376
377 moxart_init_sg(host, data);
378
379 datactrl = DCR_DATA_EN | (blksz_bits & DCR_BLK_SIZE);
380
381 if (data->flags & MMC_DATA_WRITE)
382 datactrl |= DCR_DATA_WRITE;
383
384 if ((host->data_len > host->fifo_width) && host->have_dma)
385 datactrl |= DCR_DMA_EN;
386
387 writel(DCR_DATA_FIFO_RESET, host->base + REG_DATA_CONTROL);
388 writel(MASK_DATA | FIFO_URUN | FIFO_ORUN, host->base + REG_CLEAR);
389 writel(host->rate, host->base + REG_DATA_TIMER);
390 writel(host->data_len, host->base + REG_DATA_LENGTH);
391 writel(datactrl, host->base + REG_DATA_CONTROL);
392}
393
394static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
395{
396 struct moxart_host *host = mmc_priv(mmc);
397 unsigned long flags;
398 u32 status;
399
400 spin_lock_irqsave(&host->lock, flags);
401
402 init_completion(&host->dma_complete);
403 init_completion(&host->pio_complete);
404
405 host->mrq = mrq;
406
407 if (readl(host->base + REG_STATUS) & CARD_DETECT) {
408 mrq->cmd->error = -ETIMEDOUT;
409 goto request_done;
410 }
411
412 moxart_prepare_data(host);
413 moxart_send_command(host, host->mrq->cmd);
414
415 if (mrq->cmd->data) {
416 if ((host->data_len > host->fifo_width) && host->have_dma) {
417
418 writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
419
420 spin_unlock_irqrestore(&host->lock, flags);
421
422 moxart_transfer_dma(mrq->cmd->data, host);
423
424 spin_lock_irqsave(&host->lock, flags);
425 } else {
426
427 writel(MASK_INTR_PIO, host->base + REG_INTERRUPT_MASK);
428
429 spin_unlock_irqrestore(&host->lock, flags);
430
431 /* PIO transfers start from interrupt. */
432 wait_for_completion_interruptible_timeout(&host->pio_complete,
433 host->timeout);
434
435 spin_lock_irqsave(&host->lock, flags);
436 }
437
438 if (host->is_removed) {
439 dev_err(mmc_dev(host->mmc), "card removed\n");
440 mrq->cmd->error = -ETIMEDOUT;
441 goto request_done;
442 }
443
444 if (moxart_wait_for_status(host, MASK_DATA, &status)
445 == -ETIMEDOUT) {
446 mrq->cmd->data->error = -ETIMEDOUT;
447 goto request_done;
448 }
449
450 if (status & DATA_CRC_FAIL)
451 mrq->cmd->data->error = -ETIMEDOUT;
452
453 if (mrq->cmd->data->stop)
454 moxart_send_command(host, mrq->cmd->data->stop);
455 }
456
457request_done:
458 spin_unlock_irqrestore(&host->lock, flags);
459 mmc_request_done(host->mmc, mrq);
460}
461
462static irqreturn_t moxart_irq(int irq, void *devid)
463{
464 struct moxart_host *host = (struct moxart_host *)devid;
465 u32 status;
466
467 spin_lock(&host->lock);
468
469 status = readl(host->base + REG_STATUS);
470 if (status & CARD_CHANGE) {
471 host->is_removed = status & CARD_DETECT;
472 if (host->is_removed && host->have_dma) {
473 dmaengine_terminate_all(host->dma_chan_tx);
474 dmaengine_terminate_all(host->dma_chan_rx);
475 }
476 host->mrq = NULL;
477 writel(MASK_INTR_PIO, host->base + REG_CLEAR);
478 writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
479 mmc_detect_change(host->mmc, 0);
480 }
481 if (status & (FIFO_ORUN | FIFO_URUN) && host->mrq)
482 moxart_transfer_pio(host);
483
484 spin_unlock(&host->lock);
485
486 return IRQ_HANDLED;
487}
488
489static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
490{
491 struct moxart_host *host = mmc_priv(mmc);
492 unsigned long flags;
493 u8 power, div;
494 u32 ctrl;
495
496 spin_lock_irqsave(&host->lock, flags);
497
498 if (ios->clock) {
499 for (div = 0; div < CLK_DIV_MASK; ++div) {
500 if (ios->clock >= host->sysclk / (2 * (div + 1)))
501 break;
502 }
503 ctrl = CLK_SD | div;
504 host->rate = host->sysclk / (2 * (div + 1));
505 if (host->rate > host->sysclk)
506 ctrl |= CLK_HISPD;
507 writel(ctrl, host->base + REG_CLOCK_CONTROL);
508 }
509
510 if (ios->power_mode == MMC_POWER_OFF) {
511 writel(readl(host->base + REG_POWER_CONTROL) & ~SD_POWER_ON,
512 host->base + REG_POWER_CONTROL);
513 } else {
514 if (ios->vdd < MIN_POWER)
515 power = 0;
516 else
517 power = ios->vdd - MIN_POWER;
518
519 writel(SD_POWER_ON | (u32) power,
520 host->base + REG_POWER_CONTROL);
521 }
522
523 switch (ios->bus_width) {
524 case MMC_BUS_WIDTH_4:
525 writel(BUS_WIDTH_4, host->base + REG_BUS_WIDTH);
526 break;
527 default:
528 writel(BUS_WIDTH_1, host->base + REG_BUS_WIDTH);
529 break;
530 }
531
532 spin_unlock_irqrestore(&host->lock, flags);
533}
534
535
536static int moxart_get_ro(struct mmc_host *mmc)
537{
538 struct moxart_host *host = mmc_priv(mmc);
539
540 return !!(readl(host->base + REG_STATUS) & WRITE_PROT);
541}
542
543static const struct mmc_host_ops moxart_ops = {
544 .request = moxart_request,
545 .set_ios = moxart_set_ios,
546 .get_ro = moxart_get_ro,
547};
548
549static int moxart_probe(struct platform_device *pdev)
550{
551 struct device *dev = &pdev->dev;
552 struct device_node *node = dev->of_node;
553 struct resource res_mmc;
554 struct mmc_host *mmc;
555 struct moxart_host *host = NULL;
556 struct dma_slave_config cfg;
557 struct clk *clk;
558 void __iomem *reg_mmc;
559 int irq, ret;
560 u32 i;
561
562 mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
563 if (!mmc) {
564 dev_err(dev, "mmc_alloc_host failed\n");
565 ret = -ENOMEM;
566 goto out_mmc;
567 }
568
569 ret = of_address_to_resource(node, 0, &res_mmc);
570 if (ret) {
571 dev_err(dev, "of_address_to_resource failed\n");
572 goto out_mmc;
573 }
574
575 irq = irq_of_parse_and_map(node, 0);
576 if (irq <= 0) {
577 dev_err(dev, "irq_of_parse_and_map failed\n");
578 ret = -EINVAL;
579 goto out_mmc;
580 }
581
582 clk = devm_clk_get(dev, NULL);
583 if (IS_ERR(clk)) {
584 ret = PTR_ERR(clk);
585 goto out_mmc;
586 }
587
588 reg_mmc = devm_ioremap_resource(dev, &res_mmc);
589 if (IS_ERR(reg_mmc)) {
590 ret = PTR_ERR(reg_mmc);
591 goto out_mmc;
592 }
593
594 ret = mmc_of_parse(mmc);
595 if (ret)
596 goto out_mmc;
597
598 host = mmc_priv(mmc);
599 host->mmc = mmc;
600 host->base = reg_mmc;
601 host->reg_phys = res_mmc.start;
602 host->timeout = msecs_to_jiffies(1000);
603 host->sysclk = clk_get_rate(clk);
604 host->fifo_width = readl(host->base + REG_FEATURE) << 2;
605 host->dma_chan_tx = dma_request_chan(dev, "tx");
606 host->dma_chan_rx = dma_request_chan(dev, "rx");
607
608 spin_lock_init(&host->lock);
609
610 mmc->ops = &moxart_ops;
611 mmc->f_max = DIV_ROUND_CLOSEST(host->sysclk, 2);
612 mmc->f_min = DIV_ROUND_CLOSEST(host->sysclk, CLK_DIV_MASK * 2);
613 mmc->ocr_avail = 0xffff00; /* Support 2.0v - 3.6v power. */
614
615 if (IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) {
616 if (PTR_ERR(host->dma_chan_tx) == -EPROBE_DEFER ||
617 PTR_ERR(host->dma_chan_rx) == -EPROBE_DEFER) {
618 ret = -EPROBE_DEFER;
619 goto out;
620 }
621 if (!IS_ERR(host->dma_chan_tx)) {
622 dma_release_channel(host->dma_chan_tx);
623 host->dma_chan_tx = NULL;
624 }
625 if (!IS_ERR(host->dma_chan_rx)) {
626 dma_release_channel(host->dma_chan_rx);
627 host->dma_chan_rx = NULL;
628 }
629 dev_dbg(dev, "PIO mode transfer enabled\n");
630 host->have_dma = false;
631 } else {
632 dev_dbg(dev, "DMA channels found (%p,%p)\n",
633 host->dma_chan_tx, host->dma_chan_rx);
634 host->have_dma = true;
635
636 memset(&cfg, 0, sizeof(cfg));
637 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
638 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
639
640 cfg.direction = DMA_MEM_TO_DEV;
641 cfg.src_addr = 0;
642 cfg.dst_addr = host->reg_phys + REG_DATA_WINDOW;
643 dmaengine_slave_config(host->dma_chan_tx, &cfg);
644
645 cfg.direction = DMA_DEV_TO_MEM;
646 cfg.src_addr = host->reg_phys + REG_DATA_WINDOW;
647 cfg.dst_addr = 0;
648 dmaengine_slave_config(host->dma_chan_rx, &cfg);
649 }
650
651 if (readl(host->base + REG_BUS_WIDTH) & BUS_WIDTH_4_SUPPORT)
652 mmc->caps |= MMC_CAP_4_BIT_DATA;
653
654 writel(0, host->base + REG_INTERRUPT_MASK);
655
656 writel(CMD_SDC_RESET, host->base + REG_COMMAND);
657 for (i = 0; i < MAX_RETRIES; i++) {
658 if (!(readl(host->base + REG_COMMAND) & CMD_SDC_RESET))
659 break;
660 udelay(5);
661 }
662
663 ret = devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host);
664 if (ret)
665 goto out;
666
667 dev_set_drvdata(dev, mmc);
668 ret = mmc_add_host(mmc);
669 if (ret)
670 goto out;
671
672 dev_dbg(dev, "IRQ=%d, FIFO is %d bytes\n", irq, host->fifo_width);
673
674 return 0;
675
676out:
677 if (!IS_ERR_OR_NULL(host->dma_chan_tx))
678 dma_release_channel(host->dma_chan_tx);
679 if (!IS_ERR_OR_NULL(host->dma_chan_rx))
680 dma_release_channel(host->dma_chan_rx);
681out_mmc:
682 if (mmc)
683 mmc_free_host(mmc);
684 return ret;
685}
686
687static int moxart_remove(struct platform_device *pdev)
688{
689 struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
690 struct moxart_host *host = mmc_priv(mmc);
691
692 dev_set_drvdata(&pdev->dev, NULL);
693
694 if (!IS_ERR_OR_NULL(host->dma_chan_tx))
695 dma_release_channel(host->dma_chan_tx);
696 if (!IS_ERR_OR_NULL(host->dma_chan_rx))
697 dma_release_channel(host->dma_chan_rx);
698 mmc_remove_host(mmc);
699
700 writel(0, host->base + REG_INTERRUPT_MASK);
701 writel(0, host->base + REG_POWER_CONTROL);
702 writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF,
703 host->base + REG_CLOCK_CONTROL);
704 mmc_free_host(mmc);
705
706 return 0;
707}
708
709static const struct of_device_id moxart_mmc_match[] = {
710 { .compatible = "moxa,moxart-mmc" },
711 { .compatible = "faraday,ftsdc010" },
712 { }
713};
714MODULE_DEVICE_TABLE(of, moxart_mmc_match);
715
716static struct platform_driver moxart_mmc_driver = {
717 .probe = moxart_probe,
718 .remove = moxart_remove,
719 .driver = {
720 .name = "mmc-moxart",
721 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
722 .of_match_table = moxart_mmc_match,
723 },
724};
725module_platform_driver(moxart_mmc_driver);
726
727MODULE_ALIAS("platform:mmc-moxart");
728MODULE_DESCRIPTION("MOXA ART MMC driver");
729MODULE_LICENSE("GPL v2");
730MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");
1/*
2 * MOXA ART MMC host driver.
3 *
4 * Copyright (C) 2014 Jonas Jensen
5 *
6 * Jonas Jensen <jonas.jensen@gmail.com>
7 *
8 * Based on code from
9 * Moxa Technologies Co., Ltd. <www.moxa.com>
10 *
11 * This file is licensed under the terms of the GNU General Public
12 * License version 2. This program is licensed "as is" without any
13 * warranty of any kind, whether express or implied.
14 */
15
16#include <linux/module.h>
17#include <linux/init.h>
18#include <linux/platform_device.h>
19#include <linux/delay.h>
20#include <linux/errno.h>
21#include <linux/interrupt.h>
22#include <linux/blkdev.h>
23#include <linux/dma-mapping.h>
24#include <linux/dmaengine.h>
25#include <linux/mmc/host.h>
26#include <linux/mmc/sd.h>
27#include <linux/sched.h>
28#include <linux/io.h>
29#include <linux/of_address.h>
30#include <linux/of_irq.h>
31#include <linux/clk.h>
32#include <linux/bitops.h>
33#include <linux/of_dma.h>
34#include <linux/spinlock.h>
35
36#define REG_COMMAND 0
37#define REG_ARGUMENT 4
38#define REG_RESPONSE0 8
39#define REG_RESPONSE1 12
40#define REG_RESPONSE2 16
41#define REG_RESPONSE3 20
42#define REG_RESPONSE_COMMAND 24
43#define REG_DATA_CONTROL 28
44#define REG_DATA_TIMER 32
45#define REG_DATA_LENGTH 36
46#define REG_STATUS 40
47#define REG_CLEAR 44
48#define REG_INTERRUPT_MASK 48
49#define REG_POWER_CONTROL 52
50#define REG_CLOCK_CONTROL 56
51#define REG_BUS_WIDTH 60
52#define REG_DATA_WINDOW 64
53#define REG_FEATURE 68
54#define REG_REVISION 72
55
56/* REG_COMMAND */
57#define CMD_SDC_RESET BIT(10)
58#define CMD_EN BIT(9)
59#define CMD_APP_CMD BIT(8)
60#define CMD_LONG_RSP BIT(7)
61#define CMD_NEED_RSP BIT(6)
62#define CMD_IDX_MASK 0x3f
63
64/* REG_RESPONSE_COMMAND */
65#define RSP_CMD_APP BIT(6)
66#define RSP_CMD_IDX_MASK 0x3f
67
68/* REG_DATA_CONTROL */
69#define DCR_DATA_FIFO_RESET BIT(8)
70#define DCR_DATA_THRES BIT(7)
71#define DCR_DATA_EN BIT(6)
72#define DCR_DMA_EN BIT(5)
73#define DCR_DATA_WRITE BIT(4)
74#define DCR_BLK_SIZE 0x0f
75
76/* REG_DATA_LENGTH */
77#define DATA_LEN_MASK 0xffffff
78
79/* REG_STATUS */
80#define WRITE_PROT BIT(12)
81#define CARD_DETECT BIT(11)
82/* 1-10 below can be sent to either registers, interrupt or clear. */
83#define CARD_CHANGE BIT(10)
84#define FIFO_ORUN BIT(9)
85#define FIFO_URUN BIT(8)
86#define DATA_END BIT(7)
87#define CMD_SENT BIT(6)
88#define DATA_CRC_OK BIT(5)
89#define RSP_CRC_OK BIT(4)
90#define DATA_TIMEOUT BIT(3)
91#define RSP_TIMEOUT BIT(2)
92#define DATA_CRC_FAIL BIT(1)
93#define RSP_CRC_FAIL BIT(0)
94
95#define MASK_RSP (RSP_TIMEOUT | RSP_CRC_FAIL | \
96 RSP_CRC_OK | CARD_DETECT | CMD_SENT)
97
98#define MASK_DATA (DATA_CRC_OK | DATA_END | \
99 DATA_CRC_FAIL | DATA_TIMEOUT)
100
101#define MASK_INTR_PIO (FIFO_URUN | FIFO_ORUN | CARD_CHANGE)
102
103/* REG_POWER_CONTROL */
104#define SD_POWER_ON BIT(4)
105#define SD_POWER_MASK 0x0f
106
107/* REG_CLOCK_CONTROL */
108#define CLK_HISPD BIT(9)
109#define CLK_OFF BIT(8)
110#define CLK_SD BIT(7)
111#define CLK_DIV_MASK 0x7f
112
113/* REG_BUS_WIDTH */
114#define BUS_WIDTH_4_SUPPORT BIT(3)
115#define BUS_WIDTH_4 BIT(2)
116#define BUS_WIDTH_1 BIT(0)
117
118#define MMC_VDD_360 23
119#define MIN_POWER (MMC_VDD_360 - SD_POWER_MASK)
120#define MAX_RETRIES 500000
121
122struct moxart_host {
123 spinlock_t lock;
124
125 void __iomem *base;
126
127 phys_addr_t reg_phys;
128
129 struct dma_chan *dma_chan_tx;
130 struct dma_chan *dma_chan_rx;
131 struct dma_async_tx_descriptor *tx_desc;
132 struct mmc_host *mmc;
133 struct mmc_request *mrq;
134 struct completion dma_complete;
135 struct completion pio_complete;
136
137 struct sg_mapping_iter sg_miter;
138 u32 data_len;
139 u32 fifo_width;
140 u32 timeout;
141 u32 rate;
142
143 long sysclk;
144
145 bool have_dma;
146 bool is_removed;
147};
148
149static int moxart_wait_for_status(struct moxart_host *host,
150 u32 mask, u32 *status)
151{
152 int ret = -ETIMEDOUT;
153 u32 i;
154
155 for (i = 0; i < MAX_RETRIES; i++) {
156 *status = readl(host->base + REG_STATUS);
157 if (!(*status & mask)) {
158 udelay(5);
159 continue;
160 }
161 writel(*status & mask, host->base + REG_CLEAR);
162 ret = 0;
163 break;
164 }
165
166 if (ret)
167 dev_err(mmc_dev(host->mmc), "timed out waiting for status\n");
168
169 return ret;
170}
171
172
173static void moxart_send_command(struct moxart_host *host,
174 struct mmc_command *cmd)
175{
176 u32 status, cmdctrl;
177
178 writel(RSP_TIMEOUT | RSP_CRC_OK |
179 RSP_CRC_FAIL | CMD_SENT, host->base + REG_CLEAR);
180 writel(cmd->arg, host->base + REG_ARGUMENT);
181
182 cmdctrl = cmd->opcode & CMD_IDX_MASK;
183 if (cmdctrl == SD_APP_SET_BUS_WIDTH || cmdctrl == SD_APP_OP_COND ||
184 cmdctrl == SD_APP_SEND_SCR || cmdctrl == SD_APP_SD_STATUS ||
185 cmdctrl == SD_APP_SEND_NUM_WR_BLKS)
186 cmdctrl |= CMD_APP_CMD;
187
188 if (cmd->flags & MMC_RSP_PRESENT)
189 cmdctrl |= CMD_NEED_RSP;
190
191 if (cmd->flags & MMC_RSP_136)
192 cmdctrl |= CMD_LONG_RSP;
193
194 writel(cmdctrl | CMD_EN, host->base + REG_COMMAND);
195
196 if (moxart_wait_for_status(host, MASK_RSP, &status) == -ETIMEDOUT)
197 cmd->error = -ETIMEDOUT;
198
199 if (status & RSP_TIMEOUT) {
200 cmd->error = -ETIMEDOUT;
201 return;
202 }
203 if (status & RSP_CRC_FAIL) {
204 cmd->error = -EIO;
205 return;
206 }
207 if (status & RSP_CRC_OK) {
208 if (cmd->flags & MMC_RSP_136) {
209 cmd->resp[3] = readl(host->base + REG_RESPONSE0);
210 cmd->resp[2] = readl(host->base + REG_RESPONSE1);
211 cmd->resp[1] = readl(host->base + REG_RESPONSE2);
212 cmd->resp[0] = readl(host->base + REG_RESPONSE3);
213 } else {
214 cmd->resp[0] = readl(host->base + REG_RESPONSE0);
215 }
216 }
217}
218
219static void moxart_dma_complete(void *param)
220{
221 struct moxart_host *host = param;
222
223 complete(&host->dma_complete);
224}
225
226static bool moxart_use_dma(struct moxart_host *host)
227{
228 return (host->data_len > host->fifo_width) && host->have_dma;
229}
230
231static void moxart_transfer_dma(struct mmc_data *data, struct moxart_host *host)
232{
233 u32 len, dir_slave;
234 struct dma_async_tx_descriptor *desc = NULL;
235 struct dma_chan *dma_chan;
236
237 if (host->data_len == data->bytes_xfered)
238 return;
239
240 if (data->flags & MMC_DATA_WRITE) {
241 dma_chan = host->dma_chan_tx;
242 dir_slave = DMA_MEM_TO_DEV;
243 } else {
244 dma_chan = host->dma_chan_rx;
245 dir_slave = DMA_DEV_TO_MEM;
246 }
247
248 len = dma_map_sg(dma_chan->device->dev, data->sg,
249 data->sg_len, mmc_get_dma_dir(data));
250
251 if (len > 0) {
252 desc = dmaengine_prep_slave_sg(dma_chan, data->sg,
253 len, dir_slave,
254 DMA_PREP_INTERRUPT |
255 DMA_CTRL_ACK);
256 } else {
257 dev_err(mmc_dev(host->mmc), "dma_map_sg returned zero length\n");
258 }
259
260 if (desc) {
261 host->tx_desc = desc;
262 desc->callback = moxart_dma_complete;
263 desc->callback_param = host;
264 dmaengine_submit(desc);
265 dma_async_issue_pending(dma_chan);
266 }
267
268 wait_for_completion_interruptible_timeout(&host->dma_complete,
269 host->timeout);
270
271 data->bytes_xfered = host->data_len;
272
273 dma_unmap_sg(dma_chan->device->dev,
274 data->sg, data->sg_len,
275 mmc_get_dma_dir(data));
276}
277
278
279static void moxart_transfer_pio(struct moxart_host *host)
280{
281 struct sg_mapping_iter *sgm = &host->sg_miter;
282 struct mmc_data *data = host->mrq->cmd->data;
283 u32 *sgp, len = 0, remain, status;
284
285 if (host->data_len == data->bytes_xfered)
286 return;
287
288 /*
289 * By updating sgm->consumes this will get a proper pointer into the
290 * buffer at any time.
291 */
292 if (!sg_miter_next(sgm)) {
293 /* This shold not happen */
294 dev_err(mmc_dev(host->mmc), "ran out of scatterlist prematurely\n");
295 data->error = -EINVAL;
296 complete(&host->pio_complete);
297 return;
298 }
299 sgp = sgm->addr;
300 remain = sgm->length;
301 if (remain > host->data_len)
302 remain = host->data_len;
303 sgm->consumed = 0;
304
305 if (data->flags & MMC_DATA_WRITE) {
306 while (remain > 0) {
307 if (moxart_wait_for_status(host, FIFO_URUN, &status)
308 == -ETIMEDOUT) {
309 data->error = -ETIMEDOUT;
310 complete(&host->pio_complete);
311 return;
312 }
313 for (len = 0; len < remain && len < host->fifo_width;) {
314 iowrite32(*sgp, host->base + REG_DATA_WINDOW);
315 sgp++;
316 len += 4;
317 }
318 sgm->consumed += len;
319 remain -= len;
320 }
321
322 } else {
323 while (remain > 0) {
324 if (moxart_wait_for_status(host, FIFO_ORUN, &status)
325 == -ETIMEDOUT) {
326 data->error = -ETIMEDOUT;
327 complete(&host->pio_complete);
328 return;
329 }
330 for (len = 0; len < remain && len < host->fifo_width;) {
331 *sgp = ioread32(host->base + REG_DATA_WINDOW);
332 sgp++;
333 len += 4;
334 }
335 sgm->consumed += len;
336 remain -= len;
337 }
338 }
339
340 data->bytes_xfered += sgm->consumed;
341 if (host->data_len == data->bytes_xfered) {
342 complete(&host->pio_complete);
343 return;
344 }
345}
346
347static void moxart_prepare_data(struct moxart_host *host)
348{
349 struct mmc_data *data = host->mrq->cmd->data;
350 unsigned int flags = SG_MITER_ATOMIC; /* Used from IRQ */
351 u32 datactrl;
352 int blksz_bits;
353
354 if (!data)
355 return;
356
357 host->data_len = data->blocks * data->blksz;
358 blksz_bits = ffs(data->blksz) - 1;
359 BUG_ON(1 << blksz_bits != data->blksz);
360
361 datactrl = DCR_DATA_EN | (blksz_bits & DCR_BLK_SIZE);
362
363 if (data->flags & MMC_DATA_WRITE) {
364 flags |= SG_MITER_FROM_SG;
365 datactrl |= DCR_DATA_WRITE;
366 } else {
367 flags |= SG_MITER_TO_SG;
368 }
369
370 if (moxart_use_dma(host))
371 datactrl |= DCR_DMA_EN;
372 else
373 sg_miter_start(&host->sg_miter, data->sg, data->sg_len, flags);
374
375 writel(DCR_DATA_FIFO_RESET, host->base + REG_DATA_CONTROL);
376 writel(MASK_DATA | FIFO_URUN | FIFO_ORUN, host->base + REG_CLEAR);
377 writel(host->rate, host->base + REG_DATA_TIMER);
378 writel(host->data_len, host->base + REG_DATA_LENGTH);
379 writel(datactrl, host->base + REG_DATA_CONTROL);
380}
381
382static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
383{
384 struct moxart_host *host = mmc_priv(mmc);
385 unsigned long flags;
386 u32 status;
387
388 spin_lock_irqsave(&host->lock, flags);
389
390 init_completion(&host->dma_complete);
391 init_completion(&host->pio_complete);
392
393 host->mrq = mrq;
394
395 if (readl(host->base + REG_STATUS) & CARD_DETECT) {
396 mrq->cmd->error = -ETIMEDOUT;
397 goto request_done;
398 }
399
400 moxart_prepare_data(host);
401 moxart_send_command(host, host->mrq->cmd);
402
403 if (mrq->cmd->data) {
404 if (moxart_use_dma(host)) {
405
406 writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
407
408 spin_unlock_irqrestore(&host->lock, flags);
409
410 moxart_transfer_dma(mrq->cmd->data, host);
411
412 spin_lock_irqsave(&host->lock, flags);
413 } else {
414
415 writel(MASK_INTR_PIO, host->base + REG_INTERRUPT_MASK);
416
417 spin_unlock_irqrestore(&host->lock, flags);
418
419 /* PIO transfers start from interrupt. */
420 wait_for_completion_interruptible_timeout(&host->pio_complete,
421 host->timeout);
422
423 spin_lock_irqsave(&host->lock, flags);
424 }
425
426 if (host->is_removed) {
427 dev_err(mmc_dev(host->mmc), "card removed\n");
428 mrq->cmd->error = -ETIMEDOUT;
429 goto request_done;
430 }
431
432 if (moxart_wait_for_status(host, MASK_DATA, &status)
433 == -ETIMEDOUT) {
434 mrq->cmd->data->error = -ETIMEDOUT;
435 goto request_done;
436 }
437
438 if (status & DATA_CRC_FAIL)
439 mrq->cmd->data->error = -ETIMEDOUT;
440
441 if (mrq->cmd->data->stop)
442 moxart_send_command(host, mrq->cmd->data->stop);
443 }
444
445request_done:
446 if (!moxart_use_dma(host))
447 sg_miter_stop(&host->sg_miter);
448
449 spin_unlock_irqrestore(&host->lock, flags);
450 mmc_request_done(host->mmc, mrq);
451}
452
453static irqreturn_t moxart_irq(int irq, void *devid)
454{
455 struct moxart_host *host = (struct moxart_host *)devid;
456 u32 status;
457
458 spin_lock(&host->lock);
459
460 status = readl(host->base + REG_STATUS);
461 if (status & CARD_CHANGE) {
462 host->is_removed = status & CARD_DETECT;
463 if (host->is_removed && host->have_dma) {
464 dmaengine_terminate_all(host->dma_chan_tx);
465 dmaengine_terminate_all(host->dma_chan_rx);
466 }
467 host->mrq = NULL;
468 writel(MASK_INTR_PIO, host->base + REG_CLEAR);
469 writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
470 mmc_detect_change(host->mmc, 0);
471 }
472 if (status & (FIFO_ORUN | FIFO_URUN) && host->mrq)
473 moxart_transfer_pio(host);
474
475 spin_unlock(&host->lock);
476
477 return IRQ_HANDLED;
478}
479
480static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
481{
482 struct moxart_host *host = mmc_priv(mmc);
483 unsigned long flags;
484 u8 power, div;
485 u32 ctrl;
486
487 spin_lock_irqsave(&host->lock, flags);
488
489 if (ios->clock) {
490 for (div = 0; div < CLK_DIV_MASK; ++div) {
491 if (ios->clock >= host->sysclk / (2 * (div + 1)))
492 break;
493 }
494 ctrl = CLK_SD | div;
495 host->rate = host->sysclk / (2 * (div + 1));
496 if (host->rate > host->sysclk)
497 ctrl |= CLK_HISPD;
498 writel(ctrl, host->base + REG_CLOCK_CONTROL);
499 }
500
501 if (ios->power_mode == MMC_POWER_OFF) {
502 writel(readl(host->base + REG_POWER_CONTROL) & ~SD_POWER_ON,
503 host->base + REG_POWER_CONTROL);
504 } else {
505 if (ios->vdd < MIN_POWER)
506 power = 0;
507 else
508 power = ios->vdd - MIN_POWER;
509
510 writel(SD_POWER_ON | (u32) power,
511 host->base + REG_POWER_CONTROL);
512 }
513
514 switch (ios->bus_width) {
515 case MMC_BUS_WIDTH_4:
516 writel(BUS_WIDTH_4, host->base + REG_BUS_WIDTH);
517 break;
518 default:
519 writel(BUS_WIDTH_1, host->base + REG_BUS_WIDTH);
520 break;
521 }
522
523 spin_unlock_irqrestore(&host->lock, flags);
524}
525
526
527static int moxart_get_ro(struct mmc_host *mmc)
528{
529 struct moxart_host *host = mmc_priv(mmc);
530
531 return !!(readl(host->base + REG_STATUS) & WRITE_PROT);
532}
533
534static const struct mmc_host_ops moxart_ops = {
535 .request = moxart_request,
536 .set_ios = moxart_set_ios,
537 .get_ro = moxart_get_ro,
538};
539
540static int moxart_probe(struct platform_device *pdev)
541{
542 struct device *dev = &pdev->dev;
543 struct device_node *node = dev->of_node;
544 struct resource res_mmc;
545 struct mmc_host *mmc;
546 struct moxart_host *host = NULL;
547 struct dma_slave_config cfg;
548 struct clk *clk;
549 void __iomem *reg_mmc;
550 int irq, ret;
551 u32 i;
552
553 mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
554 if (!mmc) {
555 dev_err(dev, "mmc_alloc_host failed\n");
556 ret = -ENOMEM;
557 goto out_mmc;
558 }
559
560 ret = of_address_to_resource(node, 0, &res_mmc);
561 if (ret) {
562 dev_err(dev, "of_address_to_resource failed\n");
563 goto out_mmc;
564 }
565
566 irq = irq_of_parse_and_map(node, 0);
567 if (irq <= 0) {
568 dev_err(dev, "irq_of_parse_and_map failed\n");
569 ret = -EINVAL;
570 goto out_mmc;
571 }
572
573 clk = devm_clk_get(dev, NULL);
574 if (IS_ERR(clk)) {
575 ret = PTR_ERR(clk);
576 goto out_mmc;
577 }
578
579 reg_mmc = devm_ioremap_resource(dev, &res_mmc);
580 if (IS_ERR(reg_mmc)) {
581 ret = PTR_ERR(reg_mmc);
582 goto out_mmc;
583 }
584
585 ret = mmc_of_parse(mmc);
586 if (ret)
587 goto out_mmc;
588
589 host = mmc_priv(mmc);
590 host->mmc = mmc;
591 host->base = reg_mmc;
592 host->reg_phys = res_mmc.start;
593 host->timeout = msecs_to_jiffies(1000);
594 host->sysclk = clk_get_rate(clk);
595 host->fifo_width = readl(host->base + REG_FEATURE) << 2;
596 host->dma_chan_tx = dma_request_chan(dev, "tx");
597 host->dma_chan_rx = dma_request_chan(dev, "rx");
598
599 spin_lock_init(&host->lock);
600
601 mmc->ops = &moxart_ops;
602 mmc->f_max = DIV_ROUND_CLOSEST(host->sysclk, 2);
603 mmc->f_min = DIV_ROUND_CLOSEST(host->sysclk, CLK_DIV_MASK * 2);
604 mmc->ocr_avail = 0xffff00; /* Support 2.0v - 3.6v power. */
605 mmc->max_blk_size = 2048; /* Max. block length in REG_DATA_CONTROL */
606 mmc->max_req_size = DATA_LEN_MASK; /* bits 0-23 in REG_DATA_LENGTH */
607 mmc->max_blk_count = mmc->max_req_size / 512;
608
609 if (IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) {
610 if (PTR_ERR(host->dma_chan_tx) == -EPROBE_DEFER ||
611 PTR_ERR(host->dma_chan_rx) == -EPROBE_DEFER) {
612 ret = -EPROBE_DEFER;
613 goto out;
614 }
615 if (!IS_ERR(host->dma_chan_tx)) {
616 dma_release_channel(host->dma_chan_tx);
617 host->dma_chan_tx = NULL;
618 }
619 if (!IS_ERR(host->dma_chan_rx)) {
620 dma_release_channel(host->dma_chan_rx);
621 host->dma_chan_rx = NULL;
622 }
623 dev_dbg(dev, "PIO mode transfer enabled\n");
624 host->have_dma = false;
625
626 mmc->max_seg_size = mmc->max_req_size;
627 } else {
628 dev_dbg(dev, "DMA channels found (%p,%p)\n",
629 host->dma_chan_tx, host->dma_chan_rx);
630 host->have_dma = true;
631
632 memset(&cfg, 0, sizeof(cfg));
633 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
634 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
635
636 cfg.direction = DMA_MEM_TO_DEV;
637 cfg.src_addr = 0;
638 cfg.dst_addr = host->reg_phys + REG_DATA_WINDOW;
639 dmaengine_slave_config(host->dma_chan_tx, &cfg);
640
641 cfg.direction = DMA_DEV_TO_MEM;
642 cfg.src_addr = host->reg_phys + REG_DATA_WINDOW;
643 cfg.dst_addr = 0;
644 dmaengine_slave_config(host->dma_chan_rx, &cfg);
645
646 mmc->max_seg_size = min3(mmc->max_req_size,
647 dma_get_max_seg_size(host->dma_chan_rx->device->dev),
648 dma_get_max_seg_size(host->dma_chan_tx->device->dev));
649 }
650
651 if (readl(host->base + REG_BUS_WIDTH) & BUS_WIDTH_4_SUPPORT)
652 mmc->caps |= MMC_CAP_4_BIT_DATA;
653
654 writel(0, host->base + REG_INTERRUPT_MASK);
655
656 writel(CMD_SDC_RESET, host->base + REG_COMMAND);
657 for (i = 0; i < MAX_RETRIES; i++) {
658 if (!(readl(host->base + REG_COMMAND) & CMD_SDC_RESET))
659 break;
660 udelay(5);
661 }
662
663 ret = devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host);
664 if (ret)
665 goto out;
666
667 dev_set_drvdata(dev, mmc);
668 ret = mmc_add_host(mmc);
669 if (ret)
670 goto out;
671
672 dev_dbg(dev, "IRQ=%d, FIFO is %d bytes\n", irq, host->fifo_width);
673
674 return 0;
675
676out:
677 if (!IS_ERR_OR_NULL(host->dma_chan_tx))
678 dma_release_channel(host->dma_chan_tx);
679 if (!IS_ERR_OR_NULL(host->dma_chan_rx))
680 dma_release_channel(host->dma_chan_rx);
681out_mmc:
682 if (mmc)
683 mmc_free_host(mmc);
684 return ret;
685}
686
687static void moxart_remove(struct platform_device *pdev)
688{
689 struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
690 struct moxart_host *host = mmc_priv(mmc);
691
692 if (!IS_ERR_OR_NULL(host->dma_chan_tx))
693 dma_release_channel(host->dma_chan_tx);
694 if (!IS_ERR_OR_NULL(host->dma_chan_rx))
695 dma_release_channel(host->dma_chan_rx);
696 mmc_remove_host(mmc);
697
698 writel(0, host->base + REG_INTERRUPT_MASK);
699 writel(0, host->base + REG_POWER_CONTROL);
700 writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF,
701 host->base + REG_CLOCK_CONTROL);
702 mmc_free_host(mmc);
703}
704
705static const struct of_device_id moxart_mmc_match[] = {
706 { .compatible = "moxa,moxart-mmc" },
707 { .compatible = "faraday,ftsdc010" },
708 { }
709};
710MODULE_DEVICE_TABLE(of, moxart_mmc_match);
711
712static struct platform_driver moxart_mmc_driver = {
713 .probe = moxart_probe,
714 .remove_new = moxart_remove,
715 .driver = {
716 .name = "mmc-moxart",
717 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
718 .of_match_table = moxart_mmc_match,
719 },
720};
721module_platform_driver(moxart_mmc_driver);
722
723MODULE_ALIAS("platform:mmc-moxart");
724MODULE_DESCRIPTION("MOXA ART MMC driver");
725MODULE_LICENSE("GPL v2");
726MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");