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  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  Copyright 2007, Google Inc.
  4 *  Copyright 2012, Intel Inc.
  5 *
  6 *  based on omap.c driver, which was
  7 *  Copyright (C) 2004 Nokia Corporation
  8 *  Written by Tuukka Tikkanen and Juha Yrjölä <juha.yrjola@nokia.com>
  9 *  Misc hacks here and there by Tony Lindgren <tony@atomide.com>
 10 *  Other hacks (DMA, SD, etc) by David Brownell
 11 */
 12
 13#include <linux/module.h>
 14#include <linux/platform_device.h>
 15#include <linux/major.h>
 16
 17#include <linux/types.h>
 18#include <linux/pci.h>
 19#include <linux/interrupt.h>
 20
 21#include <linux/kernel.h>
 22#include <linux/fs.h>
 23#include <linux/errno.h>
 24#include <linux/hdreg.h>
 25#include <linux/kdev_t.h>
 26#include <linux/blkdev.h>
 27#include <linux/mutex.h>
 28#include <linux/scatterlist.h>
 29#include <linux/mmc/mmc.h>
 30#include <linux/mmc/sdio.h>
 31#include <linux/mmc/host.h>
 32#include <linux/mmc/card.h>
 33
 34#include <linux/moduleparam.h>
 35#include <linux/init.h>
 36#include <linux/ioport.h>
 37#include <linux/dma-mapping.h>
 38#include <linux/delay.h>
 39#include <linux/spinlock.h>
 40#include <linux/timer.h>
 41#include <linux/clk.h>
 42
 43#include <asm/io.h>
 44#include <asm/irq.h>
 45
 46#include <asm/types.h>
 47#include <linux/uaccess.h>
 48
 49#define DRIVER_NAME "goldfish_mmc"
 50
 51#define BUFFER_SIZE   16384
 52
 53#define GOLDFISH_MMC_READ(host, addr)   (readl(host->reg_base + addr))
 54#define GOLDFISH_MMC_WRITE(host, addr, x)   (writel(x, host->reg_base + addr))
 55
 56enum {
 57	/* status register */
 58	MMC_INT_STATUS	        = 0x00,
 59	/* set this to enable IRQ */
 60	MMC_INT_ENABLE	        = 0x04,
 61	/* set this to specify buffer address */
 62	MMC_SET_BUFFER          = 0x08,
 63
 64	/* MMC command number */
 65	MMC_CMD	                = 0x0C,
 66
 67	/* MMC argument */
 68	MMC_ARG	                = 0x10,
 69
 70	/* MMC response (or R2 bits 0 - 31) */
 71	MMC_RESP_0		        = 0x14,
 72
 73	/* MMC R2 response bits 32 - 63 */
 74	MMC_RESP_1		        = 0x18,
 75
 76	/* MMC R2 response bits 64 - 95 */
 77	MMC_RESP_2		        = 0x1C,
 78
 79	/* MMC R2 response bits 96 - 127 */
 80	MMC_RESP_3		        = 0x20,
 81
 82	MMC_BLOCK_LENGTH        = 0x24,
 83	MMC_BLOCK_COUNT         = 0x28,
 84
 85	/* MMC state flags */
 86	MMC_STATE               = 0x2C,
 87
 88	/* MMC_INT_STATUS bits */
 89
 90	MMC_STAT_END_OF_CMD     = 1U << 0,
 91	MMC_STAT_END_OF_DATA    = 1U << 1,
 92	MMC_STAT_STATE_CHANGE   = 1U << 2,
 93	MMC_STAT_CMD_TIMEOUT    = 1U << 3,
 94
 95	/* MMC_STATE bits */
 96	MMC_STATE_INSERTED     = 1U << 0,
 97	MMC_STATE_READ_ONLY    = 1U << 1,
 98};
 99
100/*
101 * Command types
102 */
103#define OMAP_MMC_CMDTYPE_BC	0
104#define OMAP_MMC_CMDTYPE_BCR	1
105#define OMAP_MMC_CMDTYPE_AC	2
106#define OMAP_MMC_CMDTYPE_ADTC	3
107
108
109struct goldfish_mmc_host {
110	struct mmc_request	*mrq;
111	struct mmc_command	*cmd;
112	struct mmc_data		*data;
113	struct device		*dev;
114	unsigned char		id; /* 16xx chips have 2 MMC blocks */
115	void			*virt_base;
116	unsigned int		phys_base;
117	int			irq;
118	unsigned char		bus_mode;
119	unsigned char		hw_bus_mode;
120
121	unsigned int		sg_len;
122	unsigned		dma_done:1;
123	unsigned		dma_in_use:1;
124
125	void __iomem		*reg_base;
126};
127
128static inline int
129goldfish_mmc_cover_is_open(struct goldfish_mmc_host *host)
130{
131	return 0;
132}
133
134static ssize_t
135goldfish_mmc_show_cover_switch(struct device *dev,
136			       struct device_attribute *attr, char *buf)
137{
138	struct goldfish_mmc_host *host = dev_get_drvdata(dev);
139
140	return sprintf(buf, "%s\n", goldfish_mmc_cover_is_open(host) ? "open" :
141		       "closed");
142}
143
144static DEVICE_ATTR(cover_switch, S_IRUGO, goldfish_mmc_show_cover_switch, NULL);
145
146static void
147goldfish_mmc_start_command(struct goldfish_mmc_host *host, struct mmc_command *cmd)
148{
149	u32 cmdreg;
150	u32 resptype;
151	u32 cmdtype;
152
153	host->cmd = cmd;
154
155	resptype = 0;
156	cmdtype = 0;
157
158	/* Our hardware needs to know exact type */
159	switch (mmc_resp_type(cmd)) {
160	case MMC_RSP_NONE:
161		break;
162	case MMC_RSP_R1:
163	case MMC_RSP_R1B:
164		/* resp 1, 1b, 6, 7 */
165		resptype = 1;
166		break;
167	case MMC_RSP_R2:
168		resptype = 2;
169		break;
170	case MMC_RSP_R3:
171		resptype = 3;
172		break;
173	default:
174		dev_err(mmc_dev(mmc_from_priv(host)),
175			"Invalid response type: %04x\n", mmc_resp_type(cmd));
176		break;
177	}
178
179	if (mmc_cmd_type(cmd) == MMC_CMD_ADTC)
180		cmdtype = OMAP_MMC_CMDTYPE_ADTC;
181	else if (mmc_cmd_type(cmd) == MMC_CMD_BC)
182		cmdtype = OMAP_MMC_CMDTYPE_BC;
183	else if (mmc_cmd_type(cmd) == MMC_CMD_BCR)
184		cmdtype = OMAP_MMC_CMDTYPE_BCR;
185	else
186		cmdtype = OMAP_MMC_CMDTYPE_AC;
187
188	cmdreg = cmd->opcode | (resptype << 8) | (cmdtype << 12);
189
190	if (host->bus_mode == MMC_BUSMODE_OPENDRAIN)
191		cmdreg |= 1 << 6;
192
193	if (cmd->flags & MMC_RSP_BUSY)
194		cmdreg |= 1 << 11;
195
196	if (host->data && !(host->data->flags & MMC_DATA_WRITE))
197		cmdreg |= 1 << 15;
198
199	GOLDFISH_MMC_WRITE(host, MMC_ARG, cmd->arg);
200	GOLDFISH_MMC_WRITE(host, MMC_CMD, cmdreg);
201}
202
203static void goldfish_mmc_xfer_done(struct goldfish_mmc_host *host,
204				   struct mmc_data *data)
205{
206	if (host->dma_in_use) {
207		enum dma_data_direction dma_data_dir;
208
209		dma_data_dir = mmc_get_dma_dir(data);
210
211		if (dma_data_dir == DMA_FROM_DEVICE) {
212			/*
213			 * We don't really have DMA, so we need
214			 * to copy from our platform driver buffer
215			 */
216			sg_copy_from_buffer(data->sg, 1, host->virt_base,
217					data->sg->length);
218		}
219		host->data->bytes_xfered += data->sg->length;
220		dma_unmap_sg(mmc_dev(mmc_from_priv(host)), data->sg,
221			     host->sg_len, dma_data_dir);
222	}
223
224	host->data = NULL;
225	host->sg_len = 0;
226
227	/*
228	 * NOTE:  MMC layer will sometimes poll-wait CMD13 next, issuing
229	 * dozens of requests until the card finishes writing data.
230	 * It'd be cheaper to just wait till an EOFB interrupt arrives...
231	 */
232
233	if (!data->stop) {
234		host->mrq = NULL;
235		mmc_request_done(mmc_from_priv(host), data->mrq);
236		return;
237	}
238
239	goldfish_mmc_start_command(host, data->stop);
240}
241
242static void goldfish_mmc_end_of_data(struct goldfish_mmc_host *host,
243				     struct mmc_data *data)
244{
245	if (!host->dma_in_use) {
246		goldfish_mmc_xfer_done(host, data);
247		return;
248	}
249	if (host->dma_done)
250		goldfish_mmc_xfer_done(host, data);
251}
252
253static void goldfish_mmc_cmd_done(struct goldfish_mmc_host *host,
254				  struct mmc_command *cmd)
255{
256	host->cmd = NULL;
257	if (cmd->flags & MMC_RSP_PRESENT) {
258		if (cmd->flags & MMC_RSP_136) {
259			/* response type 2 */
260			cmd->resp[3] =
261				GOLDFISH_MMC_READ(host, MMC_RESP_0);
262			cmd->resp[2] =
263				GOLDFISH_MMC_READ(host, MMC_RESP_1);
264			cmd->resp[1] =
265				GOLDFISH_MMC_READ(host, MMC_RESP_2);
266			cmd->resp[0] =
267				GOLDFISH_MMC_READ(host, MMC_RESP_3);
268		} else {
269			/* response types 1, 1b, 3, 4, 5, 6 */
270			cmd->resp[0] =
271				GOLDFISH_MMC_READ(host, MMC_RESP_0);
272		}
273	}
274
275	if (host->data == NULL || cmd->error) {
276		host->mrq = NULL;
277		mmc_request_done(mmc_from_priv(host), cmd->mrq);
278	}
279}
280
281static irqreturn_t goldfish_mmc_irq(int irq, void *dev_id)
282{
283	struct goldfish_mmc_host *host = (struct goldfish_mmc_host *)dev_id;
284	u16 status;
285	int end_command = 0;
286	int end_transfer = 0;
287	int state_changed = 0;
288	int cmd_timeout = 0;
289
290	while ((status = GOLDFISH_MMC_READ(host, MMC_INT_STATUS)) != 0) {
291		GOLDFISH_MMC_WRITE(host, MMC_INT_STATUS, status);
292
293		if (status & MMC_STAT_END_OF_CMD)
294			end_command = 1;
295
296		if (status & MMC_STAT_END_OF_DATA)
297			end_transfer = 1;
298
299		if (status & MMC_STAT_STATE_CHANGE)
300			state_changed = 1;
301
302                if (status & MMC_STAT_CMD_TIMEOUT) {
303			end_command = 0;
304			cmd_timeout = 1;
305                }
306	}
307
308	if (cmd_timeout) {
309		struct mmc_request *mrq = host->mrq;
310		mrq->cmd->error = -ETIMEDOUT;
311		host->mrq = NULL;
312		mmc_request_done(mmc_from_priv(host), mrq);
313	}
314
315	if (end_command)
316		goldfish_mmc_cmd_done(host, host->cmd);
317
318	if (end_transfer) {
319		host->dma_done = 1;
320		goldfish_mmc_end_of_data(host, host->data);
321	} else if (host->data != NULL) {
322		/*
323		 * WORKAROUND -- after porting this driver from 2.6 to 3.4,
324		 * during device initialization, cases where host->data is
325		 * non-null but end_transfer is false would occur. Doing
326		 * nothing in such cases results in no further interrupts,
327		 * and initialization failure.
328		 * TODO -- find the real cause.
329		 */
330		host->dma_done = 1;
331		goldfish_mmc_end_of_data(host, host->data);
332	}
333
334	if (state_changed) {
335		u32 state = GOLDFISH_MMC_READ(host, MMC_STATE);
336		pr_info("%s: Card detect now %d\n", __func__,
337			(state & MMC_STATE_INSERTED));
338		mmc_detect_change(mmc_from_priv(host), 0);
339	}
340
341	if (!end_command && !end_transfer && !state_changed && !cmd_timeout) {
342		status = GOLDFISH_MMC_READ(host, MMC_INT_STATUS);
343		dev_info(mmc_dev(mmc_from_priv(host)), "spurious irq 0x%04x\n",
344			 status);
345		if (status != 0) {
346			GOLDFISH_MMC_WRITE(host, MMC_INT_STATUS, status);
347			GOLDFISH_MMC_WRITE(host, MMC_INT_ENABLE, 0);
348		}
349	}
350
351	return IRQ_HANDLED;
352}
353
354static void goldfish_mmc_prepare_data(struct goldfish_mmc_host *host,
355				      struct mmc_request *req)
356{
357	struct mmc_data *data = req->data;
358	int block_size;
359	unsigned sg_len;
360	enum dma_data_direction dma_data_dir;
361
362	host->data = data;
363	if (data == NULL) {
364		GOLDFISH_MMC_WRITE(host, MMC_BLOCK_LENGTH, 0);
365		GOLDFISH_MMC_WRITE(host, MMC_BLOCK_COUNT, 0);
366		host->dma_in_use = 0;
367		return;
368	}
369
370	block_size = data->blksz;
371
372	GOLDFISH_MMC_WRITE(host, MMC_BLOCK_COUNT, data->blocks - 1);
373	GOLDFISH_MMC_WRITE(host, MMC_BLOCK_LENGTH, block_size - 1);
374
375	/*
376	 * Cope with calling layer confusion; it issues "single
377	 * block" writes using multi-block scatterlists.
378	 */
379	sg_len = (data->blocks == 1) ? 1 : data->sg_len;
380
381	dma_data_dir = mmc_get_dma_dir(data);
382
383	host->sg_len = dma_map_sg(mmc_dev(mmc_from_priv(host)), data->sg,
384				  sg_len, dma_data_dir);
385	host->dma_done = 0;
386	host->dma_in_use = 1;
387
388	if (dma_data_dir == DMA_TO_DEVICE) {
389		/*
390		 * We don't really have DMA, so we need to copy to our
391		 * platform driver buffer
392		 */
393		sg_copy_to_buffer(data->sg, 1, host->virt_base,
394				data->sg->length);
395	}
396}
397
398static void goldfish_mmc_request(struct mmc_host *mmc, struct mmc_request *req)
399{
400	struct goldfish_mmc_host *host = mmc_priv(mmc);
401
402	WARN_ON(host->mrq != NULL);
403
404	host->mrq = req;
405	goldfish_mmc_prepare_data(host, req);
406	goldfish_mmc_start_command(host, req->cmd);
407
408	/*
409	 * This is to avoid accidentally being detected as an SDIO card
410	 * in mmc_attach_sdio().
411	 */
412	if (req->cmd->opcode == SD_IO_SEND_OP_COND &&
413	    req->cmd->flags == (MMC_RSP_SPI_R4 | MMC_RSP_R4 | MMC_CMD_BCR))
414		req->cmd->error = -EINVAL;
415}
416
417static void goldfish_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
418{
419	struct goldfish_mmc_host *host = mmc_priv(mmc);
420
421	host->bus_mode = ios->bus_mode;
422	host->hw_bus_mode = host->bus_mode;
423}
424
425static int goldfish_mmc_get_ro(struct mmc_host *mmc)
426{
427	uint32_t state;
428	struct goldfish_mmc_host *host = mmc_priv(mmc);
429
430	state = GOLDFISH_MMC_READ(host, MMC_STATE);
431	return ((state & MMC_STATE_READ_ONLY) != 0);
432}
433
434static const struct mmc_host_ops goldfish_mmc_ops = {
435	.request	= goldfish_mmc_request,
436	.set_ios	= goldfish_mmc_set_ios,
437	.get_ro		= goldfish_mmc_get_ro,
438};
439
440static int goldfish_mmc_probe(struct platform_device *pdev)
441{
442	struct mmc_host *mmc;
443	struct goldfish_mmc_host *host = NULL;
444	struct resource *res;
445	int ret = 0;
446	int irq;
447	dma_addr_t buf_addr;
448
449	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
450	irq = platform_get_irq(pdev, 0);
451	if (res == NULL || irq < 0)
452		return -ENXIO;
453
454	mmc = mmc_alloc_host(sizeof(struct goldfish_mmc_host), &pdev->dev);
455	if (mmc == NULL) {
456		ret = -ENOMEM;
457		goto err_alloc_host_failed;
458	}
459
460	host = mmc_priv(mmc);
461
462	pr_err("mmc: Mapping %lX to %lX\n", (long)res->start, (long)res->end);
463	host->reg_base = ioremap(res->start, resource_size(res));
464	if (host->reg_base == NULL) {
465		ret = -ENOMEM;
466		goto ioremap_failed;
467	}
468	host->virt_base = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE,
469					     &buf_addr, GFP_KERNEL);
470
471	if (host->virt_base == 0) {
472		ret = -ENOMEM;
473		goto dma_alloc_failed;
474	}
475	host->phys_base = buf_addr;
476
477	host->id = pdev->id;
478	host->irq = irq;
479
480	mmc->ops = &goldfish_mmc_ops;
481	mmc->f_min = 400000;
482	mmc->f_max = 24000000;
483	mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
484	mmc->caps = MMC_CAP_4_BIT_DATA;
485
486	/* Use scatterlist DMA to reduce per-transfer costs.
487	 * NOTE max_seg_size assumption that small blocks aren't
488	 * normally used (except e.g. for reading SD registers).
489	 */
490	mmc->max_segs = 32;
491	mmc->max_blk_size = 2048;	/* MMC_BLOCK_LENGTH is 11 bits (+1) */
492	mmc->max_blk_count = 2048;	/* MMC_BLOCK_COUNT is 11 bits (+1) */
493	mmc->max_req_size = BUFFER_SIZE;
494	mmc->max_seg_size = mmc->max_req_size;
495
496	ret = request_irq(host->irq, goldfish_mmc_irq, 0, DRIVER_NAME, host);
497	if (ret) {
498		dev_err(&pdev->dev, "Failed IRQ Adding goldfish MMC\n");
499		goto err_request_irq_failed;
500	}
501
502	host->dev = &pdev->dev;
503	platform_set_drvdata(pdev, host);
504
505	ret = device_create_file(&pdev->dev, &dev_attr_cover_switch);
506	if (ret)
507		dev_warn(mmc_dev(mmc), "Unable to create sysfs attributes\n");
508
509	GOLDFISH_MMC_WRITE(host, MMC_SET_BUFFER, host->phys_base);
510	GOLDFISH_MMC_WRITE(host, MMC_INT_ENABLE,
511			   MMC_STAT_END_OF_CMD | MMC_STAT_END_OF_DATA |
512			   MMC_STAT_STATE_CHANGE | MMC_STAT_CMD_TIMEOUT);
513
514	mmc_add_host(mmc);
515	return 0;
516
517err_request_irq_failed:
518	dma_free_coherent(&pdev->dev, BUFFER_SIZE, host->virt_base,
519			  host->phys_base);
520dma_alloc_failed:
521	iounmap(host->reg_base);
522ioremap_failed:
523	mmc_free_host(mmc);
524err_alloc_host_failed:
525	return ret;
526}
527
528static int goldfish_mmc_remove(struct platform_device *pdev)
529{
530	struct goldfish_mmc_host *host = platform_get_drvdata(pdev);
531	struct mmc_host *mmc = mmc_from_priv(host);
532
533	BUG_ON(host == NULL);
534
535	mmc_remove_host(mmc);
536	free_irq(host->irq, host);
537	dma_free_coherent(&pdev->dev, BUFFER_SIZE, host->virt_base, host->phys_base);
538	iounmap(host->reg_base);
539	mmc_free_host(mmc);
540	return 0;
541}
542
543static struct platform_driver goldfish_mmc_driver = {
544	.probe		= goldfish_mmc_probe,
545	.remove		= goldfish_mmc_remove,
546	.driver		= {
547		.name	= DRIVER_NAME,
548	},
549};
550
551module_platform_driver(goldfish_mmc_driver);
552MODULE_LICENSE("GPL v2");