Linux Audio

Check our new training course

Loading...
Note: File does not exist in v6.2.
  1/*
  2 *  Copyright 2007, Google Inc.
  3 *  Copyright 2012, Intel Inc.
  4 *
  5 *  based on omap.c driver, which was
  6 *  Copyright (C) 2004 Nokia Corporation
  7 *  Written by Tuukka Tikkanen and Juha Yrjölä <juha.yrjola@nokia.com>
  8 *  Misc hacks here and there by Tony Lindgren <tony@atomide.com>
  9 *  Other hacks (DMA, SD, etc) by David Brownell
 10 *
 11 * This program is free software; you can redistribute it and/or modify
 12 * it under the terms of the GNU General Public License version 2 as
 13 * published by the Free Software Foundation.
 14 */
 15
 16#include <linux/module.h>
 17#include <linux/platform_device.h>
 18#include <linux/major.h>
 19
 20#include <linux/types.h>
 21#include <linux/pci.h>
 22#include <linux/interrupt.h>
 23
 24#include <linux/kernel.h>
 25#include <linux/fs.h>
 26#include <linux/errno.h>
 27#include <linux/hdreg.h>
 28#include <linux/kdev_t.h>
 29#include <linux/blkdev.h>
 30#include <linux/mutex.h>
 31#include <linux/scatterlist.h>
 32#include <linux/mmc/mmc.h>
 33#include <linux/mmc/sdio.h>
 34#include <linux/mmc/host.h>
 35#include <linux/mmc/card.h>
 36
 37#include <linux/moduleparam.h>
 38#include <linux/init.h>
 39#include <linux/ioport.h>
 40#include <linux/dma-mapping.h>
 41#include <linux/delay.h>
 42#include <linux/spinlock.h>
 43#include <linux/timer.h>
 44#include <linux/clk.h>
 45
 46#include <asm/io.h>
 47#include <asm/irq.h>
 48
 49#include <asm/types.h>
 50#include <linux/uaccess.h>
 51
 52#define DRIVER_NAME "goldfish_mmc"
 53
 54#define BUFFER_SIZE   16384
 55
 56#define GOLDFISH_MMC_READ(host, addr)   (readl(host->reg_base + addr))
 57#define GOLDFISH_MMC_WRITE(host, addr, x)   (writel(x, host->reg_base + addr))
 58
 59enum {
 60	/* status register */
 61	MMC_INT_STATUS	        = 0x00,
 62	/* set this to enable IRQ */
 63	MMC_INT_ENABLE	        = 0x04,
 64	/* set this to specify buffer address */
 65	MMC_SET_BUFFER          = 0x08,
 66
 67	/* MMC command number */
 68	MMC_CMD	                = 0x0C,
 69
 70	/* MMC argument */
 71	MMC_ARG	                = 0x10,
 72
 73	/* MMC response (or R2 bits 0 - 31) */
 74	MMC_RESP_0		        = 0x14,
 75
 76	/* MMC R2 response bits 32 - 63 */
 77	MMC_RESP_1		        = 0x18,
 78
 79	/* MMC R2 response bits 64 - 95 */
 80	MMC_RESP_2		        = 0x1C,
 81
 82	/* MMC R2 response bits 96 - 127 */
 83	MMC_RESP_3		        = 0x20,
 84
 85	MMC_BLOCK_LENGTH        = 0x24,
 86	MMC_BLOCK_COUNT         = 0x28,
 87
 88	/* MMC state flags */
 89	MMC_STATE               = 0x2C,
 90
 91	/* MMC_INT_STATUS bits */
 92
 93	MMC_STAT_END_OF_CMD     = 1U << 0,
 94	MMC_STAT_END_OF_DATA    = 1U << 1,
 95	MMC_STAT_STATE_CHANGE   = 1U << 2,
 96	MMC_STAT_CMD_TIMEOUT    = 1U << 3,
 97
 98	/* MMC_STATE bits */
 99	MMC_STATE_INSERTED     = 1U << 0,
100	MMC_STATE_READ_ONLY    = 1U << 1,
101};
102
103/*
104 * Command types
105 */
106#define OMAP_MMC_CMDTYPE_BC	0
107#define OMAP_MMC_CMDTYPE_BCR	1
108#define OMAP_MMC_CMDTYPE_AC	2
109#define OMAP_MMC_CMDTYPE_ADTC	3
110
111
112struct goldfish_mmc_host {
113	struct mmc_request	*mrq;
114	struct mmc_command	*cmd;
115	struct mmc_data		*data;
116	struct mmc_host		*mmc;
117	struct device		*dev;
118	unsigned char		id; /* 16xx chips have 2 MMC blocks */
119	void			*virt_base;
120	unsigned int		phys_base;
121	int			irq;
122	unsigned char		bus_mode;
123	unsigned char		hw_bus_mode;
124
125	unsigned int		sg_len;
126	unsigned		dma_done:1;
127	unsigned		dma_in_use:1;
128
129	void __iomem		*reg_base;
130};
131
132static inline int
133goldfish_mmc_cover_is_open(struct goldfish_mmc_host *host)
134{
135	return 0;
136}
137
138static ssize_t
139goldfish_mmc_show_cover_switch(struct device *dev,
140			       struct device_attribute *attr, char *buf)
141{
142	struct goldfish_mmc_host *host = dev_get_drvdata(dev);
143
144	return sprintf(buf, "%s\n", goldfish_mmc_cover_is_open(host) ? "open" :
145		       "closed");
146}
147
148static DEVICE_ATTR(cover_switch, S_IRUGO, goldfish_mmc_show_cover_switch, NULL);
149
150static void
151goldfish_mmc_start_command(struct goldfish_mmc_host *host, struct mmc_command *cmd)
152{
153	u32 cmdreg;
154	u32 resptype;
155	u32 cmdtype;
156
157	host->cmd = cmd;
158
159	resptype = 0;
160	cmdtype = 0;
161
162	/* Our hardware needs to know exact type */
163	switch (mmc_resp_type(cmd)) {
164	case MMC_RSP_NONE:
165		break;
166	case MMC_RSP_R1:
167	case MMC_RSP_R1B:
168		/* resp 1, 1b, 6, 7 */
169		resptype = 1;
170		break;
171	case MMC_RSP_R2:
172		resptype = 2;
173		break;
174	case MMC_RSP_R3:
175		resptype = 3;
176		break;
177	default:
178		dev_err(mmc_dev(host->mmc),
179			"Invalid response type: %04x\n", mmc_resp_type(cmd));
180		break;
181	}
182
183	if (mmc_cmd_type(cmd) == MMC_CMD_ADTC)
184		cmdtype = OMAP_MMC_CMDTYPE_ADTC;
185	else if (mmc_cmd_type(cmd) == MMC_CMD_BC)
186		cmdtype = OMAP_MMC_CMDTYPE_BC;
187	else if (mmc_cmd_type(cmd) == MMC_CMD_BCR)
188		cmdtype = OMAP_MMC_CMDTYPE_BCR;
189	else
190		cmdtype = OMAP_MMC_CMDTYPE_AC;
191
192	cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
193
194	if (host->bus_mode == MMC_BUSMODE_OPENDRAIN)
195		cmdreg |= 1 << 6;
196
197	if (cmd->flags & MMC_RSP_BUSY)
198		cmdreg |= 1 << 11;
199
200	if (host->data && !(host->data->flags & MMC_DATA_WRITE))
201		cmdreg |= 1 << 15;
202
203	GOLDFISH_MMC_WRITE(host, MMC_ARG, cmd->arg);
204	GOLDFISH_MMC_WRITE(host, MMC_CMD, cmdreg);
205}
206
207static void goldfish_mmc_xfer_done(struct goldfish_mmc_host *host,
208				   struct mmc_data *data)
209{
210	if (host->dma_in_use) {
211		enum dma_data_direction dma_data_dir;
212
213		dma_data_dir = mmc_get_dma_dir(data);
214
215		if (dma_data_dir == DMA_FROM_DEVICE) {
216			/*
217			 * We don't really have DMA, so we need
218			 * to copy from our platform driver buffer
219			 */
220			uint8_t *dest = (uint8_t *)sg_virt(data->sg);
221			memcpy(dest, host->virt_base, data->sg->length);
222		}
223		host->data->bytes_xfered += data->sg->length;
224		dma_unmap_sg(mmc_dev(host->mmc), data->sg, host->sg_len,
225			     dma_data_dir);
226	}
227
228	host->data = NULL;
229	host->sg_len = 0;
230
231	/*
232	 * NOTE:  MMC layer will sometimes poll-wait CMD13 next, issuing
233	 * dozens of requests until the card finishes writing data.
234	 * It'd be cheaper to just wait till an EOFB interrupt arrives...
235	 */
236
237	if (!data->stop) {
238		host->mrq = NULL;
239		mmc_request_done(host->mmc, data->mrq);
240		return;
241	}
242
243	goldfish_mmc_start_command(host, data->stop);
244}
245
246static void goldfish_mmc_end_of_data(struct goldfish_mmc_host *host,
247				     struct mmc_data *data)
248{
249	if (!host->dma_in_use) {
250		goldfish_mmc_xfer_done(host, data);
251		return;
252	}
253	if (host->dma_done)
254		goldfish_mmc_xfer_done(host, data);
255}
256
257static void goldfish_mmc_cmd_done(struct goldfish_mmc_host *host,
258				  struct mmc_command *cmd)
259{
260	host->cmd = NULL;
261	if (cmd->flags & MMC_RSP_PRESENT) {
262		if (cmd->flags & MMC_RSP_136) {
263			/* response type 2 */
264			cmd->resp[3] =
265				GOLDFISH_MMC_READ(host, MMC_RESP_0);
266			cmd->resp[2] =
267				GOLDFISH_MMC_READ(host, MMC_RESP_1);
268			cmd->resp[1] =
269				GOLDFISH_MMC_READ(host, MMC_RESP_2);
270			cmd->resp[0] =
271				GOLDFISH_MMC_READ(host, MMC_RESP_3);
272		} else {
273			/* response types 1, 1b, 3, 4, 5, 6 */
274			cmd->resp[0] =
275				GOLDFISH_MMC_READ(host, MMC_RESP_0);
276		}
277	}
278
279	if (host->data == NULL || cmd->error) {
280		host->mrq = NULL;
281		mmc_request_done(host->mmc, cmd->mrq);
282	}
283}
284
285static irqreturn_t goldfish_mmc_irq(int irq, void *dev_id)
286{
287	struct goldfish_mmc_host *host = (struct goldfish_mmc_host *)dev_id;
288	u16 status;
289	int end_command = 0;
290	int end_transfer = 0;
291	int state_changed = 0;
292	int cmd_timeout = 0;
293
294	while ((status = GOLDFISH_MMC_READ(host, MMC_INT_STATUS)) != 0) {
295		GOLDFISH_MMC_WRITE(host, MMC_INT_STATUS, status);
296
297		if (status & MMC_STAT_END_OF_CMD)
298			end_command = 1;
299
300		if (status & MMC_STAT_END_OF_DATA)
301			end_transfer = 1;
302
303		if (status & MMC_STAT_STATE_CHANGE)
304			state_changed = 1;
305
306                if (status & MMC_STAT_CMD_TIMEOUT) {
307			end_command = 0;
308			cmd_timeout = 1;
309                }
310	}
311
312	if (cmd_timeout) {
313		struct mmc_request *mrq = host->mrq;
314		mrq->cmd->error = -ETIMEDOUT;
315		host->mrq = NULL;
316		mmc_request_done(host->mmc, mrq);
317	}
318
319	if (end_command)
320		goldfish_mmc_cmd_done(host, host->cmd);
321
322	if (end_transfer) {
323		host->dma_done = 1;
324		goldfish_mmc_end_of_data(host, host->data);
325	} else if (host->data != NULL) {
326		/*
327		 * WORKAROUND -- after porting this driver from 2.6 to 3.4,
328		 * during device initialization, cases where host->data is
329		 * non-null but end_transfer is false would occur. Doing
330		 * nothing in such cases results in no further interrupts,
331		 * and initialization failure.
332		 * TODO -- find the real cause.
333		 */
334		host->dma_done = 1;
335		goldfish_mmc_end_of_data(host, host->data);
336	}
337
338	if (state_changed) {
339		u32 state = GOLDFISH_MMC_READ(host, MMC_STATE);
340		pr_info("%s: Card detect now %d\n", __func__,
341			(state & MMC_STATE_INSERTED));
342		mmc_detect_change(host->mmc, 0);
343	}
344
345	if (!end_command && !end_transfer && !state_changed && !cmd_timeout) {
346		status = GOLDFISH_MMC_READ(host, MMC_INT_STATUS);
347		dev_info(mmc_dev(host->mmc),"spurious irq 0x%04x\n", status);
348		if (status != 0) {
349			GOLDFISH_MMC_WRITE(host, MMC_INT_STATUS, status);
350			GOLDFISH_MMC_WRITE(host, MMC_INT_ENABLE, 0);
351		}
352	}
353
354	return IRQ_HANDLED;
355}
356
357static void goldfish_mmc_prepare_data(struct goldfish_mmc_host *host,
358				      struct mmc_request *req)
359{
360	struct mmc_data *data = req->data;
361	int block_size;
362	unsigned sg_len;
363	enum dma_data_direction dma_data_dir;
364
365	host->data = data;
366	if (data == NULL) {
367		GOLDFISH_MMC_WRITE(host, MMC_BLOCK_LENGTH, 0);
368		GOLDFISH_MMC_WRITE(host, MMC_BLOCK_COUNT, 0);
369		host->dma_in_use = 0;
370		return;
371	}
372
373	block_size = data->blksz;
374
375	GOLDFISH_MMC_WRITE(host, MMC_BLOCK_COUNT, data->blocks - 1);
376	GOLDFISH_MMC_WRITE(host, MMC_BLOCK_LENGTH, block_size - 1);
377
378	/*
379	 * Cope with calling layer confusion; it issues "single
380	 * block" writes using multi-block scatterlists.
381	 */
382	sg_len = (data->blocks == 1) ? 1 : data->sg_len;
383
384	dma_data_dir = mmc_get_dma_dir(data);
385
386	host->sg_len = dma_map_sg(mmc_dev(host->mmc), data->sg,
387				  sg_len, dma_data_dir);
388	host->dma_done = 0;
389	host->dma_in_use = 1;
390
391	if (dma_data_dir == DMA_TO_DEVICE) {
392		/*
393		 * We don't really have DMA, so we need to copy to our
394		 * platform driver buffer
395		 */
396		const uint8_t *src = (uint8_t *)sg_virt(data->sg);
397		memcpy(host->virt_base, src, data->sg->length);
398	}
399}
400
401static void goldfish_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
402{
403	struct goldfish_mmc_host *host = mmc_priv(mmc);
404
405	WARN_ON(host->mrq != NULL);
406
407	host->mrq = req;
408	goldfish_mmc_prepare_data(host, req);
409	goldfish_mmc_start_command(host, req->cmd);
410
411	/*
412	 * This is to avoid accidentally being detected as an SDIO card
413	 * in mmc_attach_sdio().
414	 */
415	if (req->cmd->opcode == SD_IO_SEND_OP_COND &&
416	    req->cmd->flags == (MMC_RSP_SPI_R4 | MMC_RSP_R4 | MMC_CMD_BCR))
417		req->cmd->error = -EINVAL;
418}
419
420static void goldfish_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
421{
422	struct goldfish_mmc_host *host = mmc_priv(mmc);
423
424	host->bus_mode = ios->bus_mode;
425	host->hw_bus_mode = host->bus_mode;
426}
427
428static int goldfish_mmc_get_ro(struct mmc_host *mmc)
429{
430	uint32_t state;
431	struct goldfish_mmc_host *host = mmc_priv(mmc);
432
433	state = GOLDFISH_MMC_READ(host, MMC_STATE);
434	return ((state & MMC_STATE_READ_ONLY) != 0);
435}
436
437static const struct mmc_host_ops goldfish_mmc_ops = {
438	.request	= goldfish_mmc_request,
439	.set_ios	= goldfish_mmc_set_ios,
440	.get_ro		= goldfish_mmc_get_ro,
441};
442
443static int goldfish_mmc_probe(struct platform_device *pdev)
444{
445	struct mmc_host *mmc;
446	struct goldfish_mmc_host *host = NULL;
447	struct resource *res;
448	int ret = 0;
449	int irq;
450	dma_addr_t buf_addr;
451
452	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
453	irq = platform_get_irq(pdev, 0);
454	if (res == NULL || irq < 0)
455		return -ENXIO;
456
457	mmc = mmc_alloc_host(sizeof(struct goldfish_mmc_host), &pdev->dev);
458	if (mmc == NULL) {
459		ret = -ENOMEM;
460		goto err_alloc_host_failed;
461	}
462
463	host = mmc_priv(mmc);
464	host->mmc = mmc;
465
466	pr_err("mmc: Mapping %lX to %lX\n", (long)res->start, (long)res->end);
467	host->reg_base = ioremap(res->start, resource_size(res));
468	if (host->reg_base == NULL) {
469		ret = -ENOMEM;
470		goto ioremap_failed;
471	}
472	host->virt_base = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE,
473					     &buf_addr, GFP_KERNEL);
474
475	if (host->virt_base == 0) {
476		ret = -ENOMEM;
477		goto dma_alloc_failed;
478	}
479	host->phys_base = buf_addr;
480
481	host->id = pdev->id;
482	host->irq = irq;
483
484	mmc->ops = &goldfish_mmc_ops;
485	mmc->f_min = 400000;
486	mmc->f_max = 24000000;
487	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
488	mmc->caps = MMC_CAP_4_BIT_DATA;
489
490	/* Use scatterlist DMA to reduce per-transfer costs.
491	 * NOTE max_seg_size assumption that small blocks aren't
492	 * normally used (except e.g. for reading SD registers).
493	 */
494	mmc->max_segs = 32;
495	mmc->max_blk_size = 2048;	/* MMC_BLOCK_LENGTH is 11 bits (+1) */
496	mmc->max_blk_count = 2048;	/* MMC_BLOCK_COUNT is 11 bits (+1) */
497	mmc->max_req_size = BUFFER_SIZE;
498	mmc->max_seg_size = mmc->max_req_size;
499
500	ret = request_irq(host->irq, goldfish_mmc_irq, 0, DRIVER_NAME, host);
501	if (ret) {
502		dev_err(&pdev->dev, "Failed IRQ Adding goldfish MMC\n");
503		goto err_request_irq_failed;
504	}
505
506	host->dev = &pdev->dev;
507	platform_set_drvdata(pdev, host);
508
509	ret = device_create_file(&pdev->dev, &dev_attr_cover_switch);
510	if (ret)
511		dev_warn(mmc_dev(host->mmc),
512			 "Unable to create sysfs attributes\n");
513
514	GOLDFISH_MMC_WRITE(host, MMC_SET_BUFFER, host->phys_base);
515	GOLDFISH_MMC_WRITE(host, MMC_INT_ENABLE,
516			   MMC_STAT_END_OF_CMD | MMC_STAT_END_OF_DATA |
517			   MMC_STAT_STATE_CHANGE | MMC_STAT_CMD_TIMEOUT);
518
519	mmc_add_host(mmc);
520	return 0;
521
522err_request_irq_failed:
523	dma_free_coherent(&pdev->dev, BUFFER_SIZE, host->virt_base,
524			  host->phys_base);
525dma_alloc_failed:
526	iounmap(host->reg_base);
527ioremap_failed:
528	mmc_free_host(host->mmc);
529err_alloc_host_failed:
530	return ret;
531}
532
533static int goldfish_mmc_remove(struct platform_device *pdev)
534{
535	struct goldfish_mmc_host *host = platform_get_drvdata(pdev);
536
537	BUG_ON(host == NULL);
538
539	mmc_remove_host(host->mmc);
540	free_irq(host->irq, host);
541	dma_free_coherent(&pdev->dev, BUFFER_SIZE, host->virt_base, host->phys_base);
542	iounmap(host->reg_base);
543	mmc_free_host(host->mmc);
544	return 0;
545}
546
547static struct platform_driver goldfish_mmc_driver = {
548	.probe		= goldfish_mmc_probe,
549	.remove		= goldfish_mmc_remove,
550	.driver		= {
551		.name	= DRIVER_NAME,
552	},
553};
554
555module_platform_driver(goldfish_mmc_driver);
556MODULE_LICENSE("GPL v2");