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v4.6
  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_8		BIT(2)
115#define BUS_WIDTH_4		BIT(1)
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_data, dir_slave;
260	unsigned long dma_time;
261	struct dma_async_tx_descriptor *desc = NULL;
262	struct dma_chan *dma_chan;
263
264	if (host->data_len == data->bytes_xfered)
265		return;
266
267	if (data->flags & MMC_DATA_WRITE) {
268		dma_chan = host->dma_chan_tx;
269		dir_data = DMA_TO_DEVICE;
270		dir_slave = DMA_MEM_TO_DEV;
271	} else {
272		dma_chan = host->dma_chan_rx;
273		dir_data = DMA_FROM_DEVICE;
274		dir_slave = DMA_DEV_TO_MEM;
275	}
276
277	len = dma_map_sg(dma_chan->device->dev, data->sg,
278			 data->sg_len, dir_data);
279
280	if (len > 0) {
281		desc = dmaengine_prep_slave_sg(dma_chan, data->sg,
282					       len, dir_slave,
283					       DMA_PREP_INTERRUPT |
284					       DMA_CTRL_ACK);
285	} else {
286		dev_err(mmc_dev(host->mmc), "dma_map_sg returned zero length\n");
287	}
288
289	if (desc) {
290		host->tx_desc = desc;
291		desc->callback = moxart_dma_complete;
292		desc->callback_param = host;
293		dmaengine_submit(desc);
294		dma_async_issue_pending(dma_chan);
295	}
296
297	data->bytes_xfered += host->data_remain;
 
298
299	dma_time = wait_for_completion_interruptible_timeout(
300		   &host->dma_complete, host->timeout);
301
302	dma_unmap_sg(dma_chan->device->dev,
303		     data->sg, data->sg_len,
304		     dir_data);
305}
306
307
308static void moxart_transfer_pio(struct moxart_host *host)
309{
 
310	struct mmc_data *data = host->mrq->cmd->data;
311	u32 *sgp, len = 0, remain, status;
312
313	if (host->data_len == data->bytes_xfered)
314		return;
315
316	sgp = sg_virt(host->cur_sg);
317	remain = host->data_remain;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
318
319	if (data->flags & MMC_DATA_WRITE) {
320		while (remain > 0) {
321			if (moxart_wait_for_status(host, FIFO_URUN, &status)
322			     == -ETIMEDOUT) {
323				data->error = -ETIMEDOUT;
324				complete(&host->pio_complete);
325				return;
326			}
327			for (len = 0; len < remain && len < host->fifo_width;) {
328				iowrite32(*sgp, host->base + REG_DATA_WINDOW);
329				sgp++;
330				len += 4;
331			}
 
332			remain -= len;
333		}
334
335	} else {
336		while (remain > 0) {
337			if (moxart_wait_for_status(host, FIFO_ORUN, &status)
338			    == -ETIMEDOUT) {
339				data->error = -ETIMEDOUT;
340				complete(&host->pio_complete);
341				return;
342			}
343			for (len = 0; len < remain && len < host->fifo_width;) {
344				/* SCR data must be read in big endian. */
345				if (data->mrq->cmd->opcode == SD_APP_SEND_SCR)
346					*sgp = ioread32be(host->base +
347							  REG_DATA_WINDOW);
348				else
349					*sgp = ioread32(host->base +
350							REG_DATA_WINDOW);
351				sgp++;
352				len += 4;
353			}
 
354			remain -= len;
355		}
356	}
357
358	data->bytes_xfered += host->data_remain - remain;
359	host->data_remain = remain;
360
361	if (host->data_len != data->bytes_xfered)
362		moxart_next_sg(host);
363	else
364		complete(&host->pio_complete);
 
 
365}
366
367static void moxart_prepare_data(struct moxart_host *host)
368{
369	struct mmc_data *data = host->mrq->cmd->data;
 
370	u32 datactrl;
371	int blksz_bits;
372
373	if (!data)
374		return;
375
376	host->data_len = data->blocks * data->blksz;
377	blksz_bits = ffs(data->blksz) - 1;
378	BUG_ON(1 << blksz_bits != data->blksz);
379
380	moxart_init_sg(host, data);
381
382	datactrl = DCR_DATA_EN | (blksz_bits & DCR_BLK_SIZE);
383
384	if (data->flags & MMC_DATA_WRITE)
 
385		datactrl |= DCR_DATA_WRITE;
 
 
 
386
387	if ((host->data_len > host->fifo_width) && host->have_dma)
388		datactrl |= DCR_DMA_EN;
 
 
389
390	writel(DCR_DATA_FIFO_RESET, host->base + REG_DATA_CONTROL);
391	writel(MASK_DATA | FIFO_URUN | FIFO_ORUN, host->base + REG_CLEAR);
392	writel(host->rate, host->base + REG_DATA_TIMER);
393	writel(host->data_len, host->base + REG_DATA_LENGTH);
394	writel(datactrl, host->base + REG_DATA_CONTROL);
395}
396
397static void moxart_request(struct mmc_host *mmc, struct mmc_request *mrq)
398{
399	struct moxart_host *host = mmc_priv(mmc);
400	unsigned long pio_time, flags;
401	u32 status;
402
403	spin_lock_irqsave(&host->lock, flags);
404
405	init_completion(&host->dma_complete);
406	init_completion(&host->pio_complete);
407
408	host->mrq = mrq;
409
410	if (readl(host->base + REG_STATUS) & CARD_DETECT) {
411		mrq->cmd->error = -ETIMEDOUT;
412		goto request_done;
413	}
414
415	moxart_prepare_data(host);
416	moxart_send_command(host, host->mrq->cmd);
417
418	if (mrq->cmd->data) {
419		if ((host->data_len > host->fifo_width) && host->have_dma) {
420
421			writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
422
423			spin_unlock_irqrestore(&host->lock, flags);
424
425			moxart_transfer_dma(mrq->cmd->data, host);
426
427			spin_lock_irqsave(&host->lock, flags);
428		} else {
429
430			writel(MASK_INTR_PIO, host->base + REG_INTERRUPT_MASK);
431
432			spin_unlock_irqrestore(&host->lock, flags);
433
434			/* PIO transfers start from interrupt. */
435			pio_time = wait_for_completion_interruptible_timeout(
436				   &host->pio_complete, host->timeout);
437
438			spin_lock_irqsave(&host->lock, flags);
439		}
440
441		if (host->is_removed) {
442			dev_err(mmc_dev(host->mmc), "card removed\n");
443			mrq->cmd->error = -ETIMEDOUT;
444			goto request_done;
445		}
446
447		if (moxart_wait_for_status(host, MASK_DATA, &status)
448		    == -ETIMEDOUT) {
449			mrq->cmd->data->error = -ETIMEDOUT;
450			goto request_done;
451		}
452
453		if (status & DATA_CRC_FAIL)
454			mrq->cmd->data->error = -ETIMEDOUT;
455
456		if (mrq->cmd->data->stop)
457			moxart_send_command(host, mrq->cmd->data->stop);
458	}
459
460request_done:
 
 
 
461	spin_unlock_irqrestore(&host->lock, flags);
462	mmc_request_done(host->mmc, mrq);
463}
464
465static irqreturn_t moxart_irq(int irq, void *devid)
466{
467	struct moxart_host *host = (struct moxart_host *)devid;
468	u32 status;
469	unsigned long flags;
470
471	spin_lock_irqsave(&host->lock, flags);
472
473	status = readl(host->base + REG_STATUS);
474	if (status & CARD_CHANGE) {
475		host->is_removed = status & CARD_DETECT;
476		if (host->is_removed && host->have_dma) {
477			dmaengine_terminate_all(host->dma_chan_tx);
478			dmaengine_terminate_all(host->dma_chan_rx);
479		}
480		host->mrq = NULL;
481		writel(MASK_INTR_PIO, host->base + REG_CLEAR);
482		writel(CARD_CHANGE, host->base + REG_INTERRUPT_MASK);
483		mmc_detect_change(host->mmc, 0);
484	}
485	if (status & (FIFO_ORUN | FIFO_URUN) && host->mrq)
486		moxart_transfer_pio(host);
487
488	spin_unlock_irqrestore(&host->lock, flags);
489
490	return IRQ_HANDLED;
491}
492
493static void moxart_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
494{
495	struct moxart_host *host = mmc_priv(mmc);
496	unsigned long flags;
497	u8 power, div;
498	u32 ctrl;
499
500	spin_lock_irqsave(&host->lock, flags);
501
502	if (ios->clock) {
503		for (div = 0; div < CLK_DIV_MASK; ++div) {
504			if (ios->clock >= host->sysclk / (2 * (div + 1)))
505				break;
506		}
507		ctrl = CLK_SD | div;
508		host->rate = host->sysclk / (2 * (div + 1));
509		if (host->rate > host->sysclk)
510			ctrl |= CLK_HISPD;
511		writel(ctrl, host->base + REG_CLOCK_CONTROL);
512	}
513
514	if (ios->power_mode == MMC_POWER_OFF) {
515		writel(readl(host->base + REG_POWER_CONTROL) & ~SD_POWER_ON,
516		       host->base + REG_POWER_CONTROL);
517	} else {
518		if (ios->vdd < MIN_POWER)
519			power = 0;
520		else
521			power = ios->vdd - MIN_POWER;
522
523		writel(SD_POWER_ON | (u32) power,
524		       host->base + REG_POWER_CONTROL);
525	}
526
527	switch (ios->bus_width) {
528	case MMC_BUS_WIDTH_4:
529		writel(BUS_WIDTH_4, host->base + REG_BUS_WIDTH);
530		break;
531	case MMC_BUS_WIDTH_8:
532		writel(BUS_WIDTH_8, host->base + REG_BUS_WIDTH);
533		break;
534	default:
535		writel(BUS_WIDTH_1, host->base + REG_BUS_WIDTH);
536		break;
537	}
538
539	spin_unlock_irqrestore(&host->lock, flags);
540}
541
542
543static int moxart_get_ro(struct mmc_host *mmc)
544{
545	struct moxart_host *host = mmc_priv(mmc);
546
547	return !!(readl(host->base + REG_STATUS) & WRITE_PROT);
548}
549
550static struct mmc_host_ops moxart_ops = {
551	.request = moxart_request,
552	.set_ios = moxart_set_ios,
553	.get_ro = moxart_get_ro,
554};
555
556static int moxart_probe(struct platform_device *pdev)
557{
558	struct device *dev = &pdev->dev;
559	struct device_node *node = dev->of_node;
560	struct resource res_mmc;
561	struct mmc_host *mmc;
562	struct moxart_host *host = NULL;
563	struct dma_slave_config cfg;
564	struct clk *clk;
565	void __iomem *reg_mmc;
566	int irq, ret;
567	u32 i;
568
569	mmc = mmc_alloc_host(sizeof(struct moxart_host), dev);
570	if (!mmc) {
571		dev_err(dev, "mmc_alloc_host failed\n");
572		ret = -ENOMEM;
573		goto out;
574	}
575
576	ret = of_address_to_resource(node, 0, &res_mmc);
577	if (ret) {
578		dev_err(dev, "of_address_to_resource failed\n");
579		goto out;
580	}
581
582	irq = irq_of_parse_and_map(node, 0);
583	if (irq <= 0) {
584		dev_err(dev, "irq_of_parse_and_map failed\n");
585		ret = -EINVAL;
586		goto out;
587	}
588
589	clk = devm_clk_get(dev, NULL);
590	if (IS_ERR(clk)) {
591		ret = PTR_ERR(clk);
592		goto out;
593	}
594
595	reg_mmc = devm_ioremap_resource(dev, &res_mmc);
596	if (IS_ERR(reg_mmc)) {
597		ret = PTR_ERR(reg_mmc);
598		goto out;
599	}
600
601	ret = mmc_of_parse(mmc);
602	if (ret)
603		goto out;
604
605	host = mmc_priv(mmc);
606	host->mmc = mmc;
607	host->base = reg_mmc;
608	host->reg_phys = res_mmc.start;
609	host->timeout = msecs_to_jiffies(1000);
610	host->sysclk = clk_get_rate(clk);
611	host->fifo_width = readl(host->base + REG_FEATURE) << 2;
612	host->dma_chan_tx = dma_request_slave_channel_reason(dev, "tx");
613	host->dma_chan_rx = dma_request_slave_channel_reason(dev, "rx");
614
615	spin_lock_init(&host->lock);
616
617	mmc->ops = &moxart_ops;
618	mmc->f_max = DIV_ROUND_CLOSEST(host->sysclk, 2);
619	mmc->f_min = DIV_ROUND_CLOSEST(host->sysclk, CLK_DIV_MASK * 2);
620	mmc->ocr_avail = 0xffff00;	/* Support 2.0v - 3.6v power. */
 
 
 
621
622	if (IS_ERR(host->dma_chan_tx) || IS_ERR(host->dma_chan_rx)) {
623		if (PTR_ERR(host->dma_chan_tx) == -EPROBE_DEFER ||
624		    PTR_ERR(host->dma_chan_rx) == -EPROBE_DEFER) {
625			ret = -EPROBE_DEFER;
626			goto out;
627		}
 
 
 
 
 
 
 
 
628		dev_dbg(dev, "PIO mode transfer enabled\n");
629		host->have_dma = false;
 
 
630	} else {
631		dev_dbg(dev, "DMA channels found (%p,%p)\n",
632			 host->dma_chan_tx, host->dma_chan_rx);
633		host->have_dma = true;
634
 
635		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
636		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
637
638		cfg.direction = DMA_MEM_TO_DEV;
639		cfg.src_addr = 0;
640		cfg.dst_addr = host->reg_phys + REG_DATA_WINDOW;
641		dmaengine_slave_config(host->dma_chan_tx, &cfg);
642
643		cfg.direction = DMA_DEV_TO_MEM;
644		cfg.src_addr = host->reg_phys + REG_DATA_WINDOW;
645		cfg.dst_addr = 0;
646		dmaengine_slave_config(host->dma_chan_rx, &cfg);
 
 
 
 
647	}
648
649	switch ((readl(host->base + REG_BUS_WIDTH) >> 3) & 3) {
650	case 1:
651		mmc->caps |= MMC_CAP_4_BIT_DATA;
652		break;
653	case 2:
654		mmc->caps |= MMC_CAP_4_BIT_DATA | MMC_CAP_8_BIT_DATA;
655		break;
656	default:
657		break;
658	}
659
660	writel(0, host->base + REG_INTERRUPT_MASK);
661
662	writel(CMD_SDC_RESET, host->base + REG_COMMAND);
663	for (i = 0; i < MAX_RETRIES; i++) {
664		if (!(readl(host->base + REG_COMMAND) & CMD_SDC_RESET))
665			break;
666		udelay(5);
667	}
668
669	ret = devm_request_irq(dev, irq, moxart_irq, 0, "moxart-mmc", host);
670	if (ret)
671		goto out;
672
673	dev_set_drvdata(dev, mmc);
674	mmc_add_host(mmc);
 
 
675
676	dev_dbg(dev, "IRQ=%d, FIFO is %d bytes\n", irq, host->fifo_width);
677
678	return 0;
679
680out:
 
 
 
 
 
681	if (mmc)
682		mmc_free_host(mmc);
683	return ret;
684}
685
686static int moxart_remove(struct platform_device *pdev)
687{
688	struct mmc_host *mmc = dev_get_drvdata(&pdev->dev);
689	struct moxart_host *host = mmc_priv(mmc);
690
691	dev_set_drvdata(&pdev->dev, NULL);
 
 
 
 
692
693	if (mmc) {
694		if (!IS_ERR(host->dma_chan_tx))
695			dma_release_channel(host->dma_chan_tx);
696		if (!IS_ERR(host->dma_chan_rx))
697			dma_release_channel(host->dma_chan_rx);
698		mmc_remove_host(mmc);
699		mmc_free_host(mmc);
700
701		writel(0, host->base + REG_INTERRUPT_MASK);
702		writel(0, host->base + REG_POWER_CONTROL);
703		writel(readl(host->base + REG_CLOCK_CONTROL) | CLK_OFF,
704		       host->base + REG_CLOCK_CONTROL);
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		.of_match_table	= moxart_mmc_match,
722	},
723};
724module_platform_driver(moxart_mmc_driver);
725
726MODULE_ALIAS("platform:mmc-moxart");
727MODULE_DESCRIPTION("MOXA ART MMC driver");
728MODULE_LICENSE("GPL v2");
729MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");
v6.9.4
  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>");