[mirror_ubuntu-bionic-kernel.git] / drivers / mtd / devices / sst25l.c

/*
 * sst25l.c
 *
 * Driver for SST25L SPI Flash chips
 *
 * Copyright © 2009 Bluewater Systems Ltd
 * Author: Andre Renaud <andre@bluewatersys.com>
 * Author: Ryan Mallon <ryan@bluewatersys.com>
 *
 * Based on m25p80.c
 *
 * This code is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#include <linux/init.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/sched.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>

#include <linux/spi/spi.h>
#include <linux/spi/flash.h>

/* Erases can take up to 3 seconds! */
#define MAX_READY_WAIT_JIFFIES	msecs_to_jiffies(3000)

#define SST25L_CMD_WRSR		0x01	/* Write status register */
#define SST25L_CMD_WRDI		0x04	/* Write disable */
#define SST25L_CMD_RDSR		0x05	/* Read status register */
#define SST25L_CMD_WREN		0x06	/* Write enable */
#define SST25L_CMD_READ		0x03	/* High speed read */

#define SST25L_CMD_EWSR		0x50	/* Enable write status register */
#define SST25L_CMD_SECTOR_ERASE	0x20	/* Erase sector */
#define SST25L_CMD_READ_ID	0x90	/* Read device ID */
#define SST25L_CMD_AAI_PROGRAM	0xaf	/* Auto address increment */

#define SST25L_STATUS_BUSY	(1 << 0)	/* Chip is busy */
#define SST25L_STATUS_WREN	(1 << 1)	/* Write enabled */
#define SST25L_STATUS_BP0	(1 << 2)	/* Block protection 0 */
#define SST25L_STATUS_BP1	(1 << 3)	/* Block protection 1 */

struct sst25l_flash {
	struct spi_device	*spi;
	struct mutex		lock;
	struct mtd_info		mtd;

	int 			partitioned;
};

struct flash_info {
	const char		*name;
	uint16_t		device_id;
	unsigned		page_size;
	unsigned		nr_pages;
	unsigned		erase_size;
};

#define to_sst25l_flash(x) container_of(x, struct sst25l_flash, mtd)

static struct flash_info __devinitdata sst25l_flash_info[] = {
	{"sst25lf020a", 0xbf43, 256, 1024, 4096},
	{"sst25lf040a",	0xbf44,	256, 2048, 4096},
};

static int sst25l_status(struct sst25l_flash *flash, int *status)
{
	struct spi_message m;
	struct spi_transfer t;
	unsigned char cmd_resp[2];
	int err;

	spi_message_init(&m);
	memset(&t, 0, sizeof(struct spi_transfer));

	cmd_resp[0] = SST25L_CMD_RDSR;
	cmd_resp[1] = 0xff;
	t.tx_buf = cmd_resp;
	t.rx_buf = cmd_resp;
	t.len = sizeof(cmd_resp);
	spi_message_add_tail(&t, &m);
	err = spi_sync(flash->spi, &m);
	if (err < 0)
		return err;

	*status = cmd_resp[1];
	return 0;
}

static int sst25l_write_enable(struct sst25l_flash *flash, int enable)
{
	unsigned char command[2];
	int status, err;

	command[0] = enable ? SST25L_CMD_WREN : SST25L_CMD_WRDI;
	err = spi_write(flash->spi, command, 1);
	if (err)
		return err;

	command[0] = SST25L_CMD_EWSR;
	err = spi_write(flash->spi, command, 1);
	if (err)
		return err;

	command[0] = SST25L_CMD_WRSR;
	command[1] = enable ? 0 : SST25L_STATUS_BP0 | SST25L_STATUS_BP1;
	err = spi_write(flash->spi, command, 2);
	if (err)
		return err;

	if (enable) {
		err = sst25l_status(flash, &status);
		if (err)
			return err;
		if (!(status & SST25L_STATUS_WREN))
			return -EROFS;
	}

	return 0;
}

static int sst25l_wait_till_ready(struct sst25l_flash *flash)
{
	unsigned long deadline;
	int status, err;

	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
	do {
		err = sst25l_status(flash, &status);
		if (err)
			return err;
		if (!(status & SST25L_STATUS_BUSY))
			return 0;

		cond_resched();
	} while (!time_after_eq(jiffies, deadline));

	return -ETIMEDOUT;
}

static int sst25l_erase_sector(struct sst25l_flash *flash, uint32_t offset)
{
	unsigned char command[4];
	int err;

	err = sst25l_write_enable(flash, 1);
	if (err)
		return err;

	command[0] = SST25L_CMD_SECTOR_ERASE;
	command[1] = offset >> 16;
	command[2] = offset >> 8;
	command[3] = offset;
	err = spi_write(flash->spi, command, 4);
	if (err)
		return err;

	err = sst25l_wait_till_ready(flash);
	if (err)
		return err;

	return sst25l_write_enable(flash, 0);
}

static int sst25l_erase(struct mtd_info *mtd, struct erase_info *instr)
{
	struct sst25l_flash *flash = to_sst25l_flash(mtd);
	uint32_t addr, end;
	int err;

	/* Sanity checks */
	if (instr->addr + instr->len > flash->mtd.size)
		return -EINVAL;

	if ((uint32_t)instr->len % mtd->erasesize)
		return -EINVAL;

	if ((uint32_t)instr->addr % mtd->erasesize)
		return -EINVAL;

	addr = instr->addr;
	end = addr + instr->len;

	mutex_lock(&flash->lock);

	err = sst25l_wait_till_ready(flash);
	if (err) {
		mutex_unlock(&flash->lock);
		return err;
	}

	while (addr < end) {
		err = sst25l_erase_sector(flash, addr);
		if (err) {
			mutex_unlock(&flash->lock);
			instr->state = MTD_ERASE_FAILED;
			dev_err(&flash->spi->dev, "Erase failed\n");
			return err;
		}

		addr += mtd->erasesize;
	}

	mutex_unlock(&flash->lock);

	instr->state = MTD_ERASE_DONE;
	mtd_erase_callback(instr);
	return 0;
}

static int sst25l_read(struct mtd_info *mtd, loff_t from, size_t len,
		       size_t *retlen, unsigned char *buf)
{
	struct sst25l_flash *flash = to_sst25l_flash(mtd);
	struct spi_transfer transfer[2];
	struct spi_message message;
	unsigned char command[4];
	int ret;

	/* Sanity checking */
	if (len == 0)
		return 0;

	if (from + len > flash->mtd.size)
		return -EINVAL;

	if (retlen)
		*retlen = 0;

	spi_message_init(&message);
	memset(&transfer, 0, sizeof(transfer));

	command[0] = SST25L_CMD_READ;
	command[1] = from >> 16;
	command[2] = from >> 8;
	command[3] = from;

	transfer[0].tx_buf = command;
	transfer[0].len = sizeof(command);
	spi_message_add_tail(&transfer[0], &message);

	transfer[1].rx_buf = buf;
	transfer[1].len = len;
	spi_message_add_tail(&transfer[1], &message);

	mutex_lock(&flash->lock);

	/* Wait for previous write/erase to complete */
	ret = sst25l_wait_till_ready(flash);
	if (ret) {
		mutex_unlock(&flash->lock);
		return ret;
	}

	spi_sync(flash->spi, &message);

	if (retlen && message.actual_length > sizeof(command))
		*retlen += message.actual_length - sizeof(command);

	mutex_unlock(&flash->lock);
	return 0;
}

static int sst25l_write(struct mtd_info *mtd, loff_t to, size_t len,
			size_t *retlen, const unsigned char *buf)
{
	struct sst25l_flash *flash = to_sst25l_flash(mtd);
	int i, j, ret, bytes, copied = 0;
	unsigned char command[5];

	/* Sanity checks */
	if (!len)
		return 0;

	if (to + len > flash->mtd.size)
		return -EINVAL;

	if ((uint32_t)to % mtd->writesize)
		return -EINVAL;

	mutex_lock(&flash->lock);

	ret = sst25l_write_enable(flash, 1);
	if (ret)
		goto out;

	for (i = 0; i < len; i += mtd->writesize) {
		ret = sst25l_wait_till_ready(flash);
		if (ret)
			goto out;

		/* Write the first byte of the page */
		command[0] = SST25L_CMD_AAI_PROGRAM;
		command[1] = (to + i) >> 16;
		command[2] = (to + i) >> 8;
		command[3] = (to + i);
		command[4] = buf[i];
		ret = spi_write(flash->spi, command, 5);
		if (ret < 0)
			goto out;
		copied++;

		/*
		 * Write the remaining bytes using auto address
		 * increment mode
		 */
		bytes = min_t(uint32_t, mtd->writesize, len - i);
		for (j = 1; j < bytes; j++, copied++) {
			ret = sst25l_wait_till_ready(flash);
			if (ret)
				goto out;

			command[1] = buf[i + j];
			ret = spi_write(flash->spi, command, 2);
			if (ret)
				goto out;
		}
	}

out:
	ret = sst25l_write_enable(flash, 0);

	if (retlen)
		*retlen = copied;

	mutex_unlock(&flash->lock);
	return ret;
}

static struct flash_info *__devinit sst25l_match_device(struct spi_device *spi)
{
	struct flash_info *flash_info = NULL;
	struct spi_message m;
	struct spi_transfer t;
	unsigned char cmd_resp[6];
	int i, err;
	uint16_t id;

	spi_message_init(&m);
	memset(&t, 0, sizeof(struct spi_transfer));

	cmd_resp[0] = SST25L_CMD_READ_ID;
	cmd_resp[1] = 0;
	cmd_resp[2] = 0;
	cmd_resp[3] = 0;
	cmd_resp[4] = 0xff;
	cmd_resp[5] = 0xff;
	t.tx_buf = cmd_resp;
	t.rx_buf = cmd_resp;
	t.len = sizeof(cmd_resp);
	spi_message_add_tail(&t, &m);
	err = spi_sync(spi, &m);
	if (err < 0) {
		dev_err(&spi->dev, "error reading device id\n");
		return NULL;
	}

	id = (cmd_resp[4] << 8) | cmd_resp[5];

	for (i = 0; i < ARRAY_SIZE(sst25l_flash_info); i++)
		if (sst25l_flash_info[i].device_id == id)
			flash_info = &sst25l_flash_info[i];

	if (!flash_info)
		dev_err(&spi->dev, "unknown id %.4x\n", id);

	return flash_info;
}

static int __devinit sst25l_probe(struct spi_device *spi)
{
	struct flash_info *flash_info;
	struct sst25l_flash *flash;
	struct flash_platform_data *data;
	int ret, i;
	struct mtd_partition *parts = NULL;
	int nr_parts = 0;

	flash_info = sst25l_match_device(spi);
	if (!flash_info)
		return -ENODEV;

	flash = kzalloc(sizeof(struct sst25l_flash), GFP_KERNEL);
	if (!flash)
		return -ENOMEM;

	flash->spi = spi;
	mutex_init(&flash->lock);
	dev_set_drvdata(&spi->dev, flash);

	data = spi->dev.platform_data;
	if (data && data->name)
		flash->mtd.name = data->name;
	else
		flash->mtd.name = dev_name(&spi->dev);

	flash->mtd.type		= MTD_NORFLASH;
	flash->mtd.flags	= MTD_CAP_NORFLASH;
	flash->mtd.erasesize	= flash_info->erase_size;
	flash->mtd.writesize	= flash_info->page_size;
	flash->mtd.size		= flash_info->page_size * flash_info->nr_pages;
	flash->mtd.erase	= sst25l_erase;
	flash->mtd.read		= sst25l_read;
	flash->mtd.write 	= sst25l_write;

	dev_info(&spi->dev, "%s (%lld KiB)\n", flash_info->name,
		 (long long)flash->mtd.size >> 10);

	DEBUG(MTD_DEBUG_LEVEL2,
	      "mtd .name = %s, .size = 0x%llx (%lldMiB) "
	      ".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n",
	      flash->mtd.name,
	      (long long)flash->mtd.size, (long long)(flash->mtd.size >> 20),
	      flash->mtd.erasesize, flash->mtd.erasesize / 1024,
	      flash->mtd.numeraseregions);


	if (mtd_has_cmdlinepart()) {
		static const char *part_probes[] = {"cmdlinepart", NULL};

		nr_parts = parse_mtd_partitions(&flash->mtd,
						part_probes,
						&parts, 0);
	}

	if (nr_parts <= 0 && data && data->parts) {
		parts = data->parts;
		nr_parts = data->nr_parts;
	}

	if (nr_parts > 0) {
		for (i = 0; i < nr_parts; i++) {
			DEBUG(MTD_DEBUG_LEVEL2, "partitions[%d] = "
			      "{.name = %s, .offset = 0x%llx, "
			      ".size = 0x%llx (%lldKiB) }\n",
			      i, parts[i].name,
			      (long long)parts[i].offset,
			      (long long)parts[i].size,
			      (long long)(parts[i].size >> 10));
		}

		flash->partitioned = 1;
		return mtd_device_register(&flash->mtd, parts,
					   nr_parts);
	}

	ret = mtd_device_register(&flash->mtd, NULL, 0);
	if (ret == 1) {
		kfree(flash);
		dev_set_drvdata(&spi->dev, NULL);
		return -ENODEV;
	}

	return 0;
}

static int __devexit sst25l_remove(struct spi_device *spi)
{
	struct sst25l_flash *flash = dev_get_drvdata(&spi->dev);
	int ret;

	ret = mtd_device_unregister(&flash->mtd);
	if (ret == 0)
		kfree(flash);
	return ret;
}

static struct spi_driver sst25l_driver = {
	.driver = {
		.name	= "sst25l",
		.bus	= &spi_bus_type,
		.owner	= THIS_MODULE,
	},
	.probe		= sst25l_probe,
	.remove		= __devexit_p(sst25l_remove),
};

static int __init sst25l_init(void)
{
	return spi_register_driver(&sst25l_driver);
}

static void __exit sst25l_exit(void)
{
	spi_unregister_driver(&sst25l_driver);
}

module_init(sst25l_init);
module_exit(sst25l_exit);

MODULE_DESCRIPTION("MTD SPI driver for SST25L Flash chips");
MODULE_AUTHOR("Andre Renaud <andre@bluewatersys.com>, "
	      "Ryan Mallon <ryan@bluewatersys.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
ec77e21b RM	1	/*
	2	* sst25l.c
	3	*
	4	* Driver for SST25L SPI Flash chips
	5	*
	6	* Copyright © 2009 Bluewater Systems Ltd
	7	* Author: Andre Renaud <andre@bluewatersys.com>
	8	* Author: Ryan Mallon <ryan@bluewatersys.com>
	9	*
	10	* Based on m25p80.c
	11	*
	12	* This code is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU General Public License version 2 as
	14	* published by the Free Software Foundation.
	15	*
	16	*/
	17
	18	#include <linux/init.h>
	19	#include <linux/module.h>
	20	#include <linux/device.h>
	21	#include <linux/mutex.h>
	22	#include <linux/interrupt.h>
5a0e3ad6	23	#include <linux/slab.h>
d43c36dc	24	#include <linux/sched.h>
ec77e21b RM	25
	26	#include <linux/mtd/mtd.h>
	27	#include <linux/mtd/partitions.h>
	28
	29	#include <linux/spi/spi.h>
	30	#include <linux/spi/flash.h>
	31
	32	/* Erases can take up to 3 seconds! */
	33	#define MAX_READY_WAIT_JIFFIES msecs_to_jiffies(3000)
	34
	35	#define SST25L_CMD_WRSR 0x01 /* Write status register */
	36	#define SST25L_CMD_WRDI 0x04 /* Write disable */
	37	#define SST25L_CMD_RDSR 0x05 /* Read status register */
	38	#define SST25L_CMD_WREN 0x06 /* Write enable */
	39	#define SST25L_CMD_READ 0x03 /* High speed read */
	40
	41	#define SST25L_CMD_EWSR 0x50 /* Enable write status register */
	42	#define SST25L_CMD_SECTOR_ERASE 0x20 /* Erase sector */
	43	#define SST25L_CMD_READ_ID 0x90 /* Read device ID */
	44	#define SST25L_CMD_AAI_PROGRAM 0xaf /* Auto address increment */
	45
	46	#define SST25L_STATUS_BUSY (1 << 0) /* Chip is busy */
	47	#define SST25L_STATUS_WREN (1 << 1) /* Write enabled */
	48	#define SST25L_STATUS_BP0 (1 << 2) /* Block protection 0 */
	49	#define SST25L_STATUS_BP1 (1 << 3) /* Block protection 1 */
	50
	51	struct sst25l_flash {
	52	struct spi_device *spi;
	53	struct mutex lock;
	54	struct mtd_info mtd;
	55
	56	int partitioned;
	57	};
	58
	59	struct flash_info {
	60	const char *name;
	61	uint16_t device_id;
	62	unsigned page_size;
	63	unsigned nr_pages;
	64	unsigned erase_size;
	65	};
	66
	67	#define to_sst25l_flash(x) container_of(x, struct sst25l_flash, mtd)
	68
61cc8276	69	static struct flash_info __devinitdata sst25l_flash_info[] = {
ec77e21b RM	70	{"sst25lf020a", 0xbf43, 256, 1024, 4096},
	71	{"sst25lf040a", 0xbf44, 256, 2048, 4096},
	72	};
	73
	74	static int sst25l_status(struct sst25l_flash flash, int status)
	75	{
0ffe0ce3 HS	76	struct spi_message m;
	77	struct spi_transfer t;
	78	unsigned char cmd_resp[2];
ec77e21b RM	79	int err;
ec77e21b RM	80
0ffe0ce3 HS	81	spi_message_init(&m);
	82	memset(&t, 0, sizeof(struct spi_transfer));
	83
	84	cmd_resp[0] = SST25L_CMD_RDSR;
	85	cmd_resp[1] = 0xff;
	86	t.tx_buf = cmd_resp;
	87	t.rx_buf = cmd_resp;
	88	t.len = sizeof(cmd_resp);
	89	spi_message_add_tail(&t, &m);
	90	err = spi_sync(flash->spi, &m);
ec77e21b RM	91	if (err < 0)
	92	return err;
	93
0ffe0ce3	94	*status = cmd_resp[1];
ec77e21b RM	95	return 0;
	96	}
	97
	98	static int sst25l_write_enable(struct sst25l_flash *flash, int enable)
	99	{
	100	unsigned char command[2];
	101	int status, err;
	102
	103	command[0] = enable ? SST25L_CMD_WREN : SST25L_CMD_WRDI;
	104	err = spi_write(flash->spi, command, 1);
	105	if (err)
	106	return err;
	107
	108	command[0] = SST25L_CMD_EWSR;
	109	err = spi_write(flash->spi, command, 1);
	110	if (err)
	111	return err;
	112
	113	command[0] = SST25L_CMD_WRSR;
	114	command[1] = enable ? 0 : SST25L_STATUS_BP0 \| SST25L_STATUS_BP1;
	115	err = spi_write(flash->spi, command, 2);
	116	if (err)
	117	return err;
	118
	119	if (enable) {
	120	err = sst25l_status(flash, &status);
	121	if (err)
	122	return err;
	123	if (!(status & SST25L_STATUS_WREN))
	124	return -EROFS;
	125	}
	126
	127	return 0;
	128	}
	129
	130	static int sst25l_wait_till_ready(struct sst25l_flash *flash)
	131	{
	132	unsigned long deadline;
	133	int status, err;
	134
	135	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
	136	do {
	137	err = sst25l_status(flash, &status);
	138	if (err)
	139	return err;
	140	if (!(status & SST25L_STATUS_BUSY))
	141	return 0;
	142
	143	cond_resched();
	144	} while (!time_after_eq(jiffies, deadline));
	145
	146	return -ETIMEDOUT;
	147	}
	148
	149	static int sst25l_erase_sector(struct sst25l_flash *flash, uint32_t offset)
	150	{
	151	unsigned char command[4];
	152	int err;
	153
	154	err = sst25l_write_enable(flash, 1);
	155	if (err)
	156	return err;
	157
	158	command[0] = SST25L_CMD_SECTOR_ERASE;
159	command[1] = offset >> 16;
160	command[2] = offset >> 8;
161	command[3] = offset;
162	err = spi_write(flash->spi, command, 4);
163	if (err)
164	return err;
165
166	err = sst25l_wait_till_ready(flash);
167	if (err)
168	return err;
169
170	return sst25l_write_enable(flash, 0);
171	}
172
173	static int sst25l_erase(struct mtd_info mtd, struct erase_info instr)
174	{
175	struct sst25l_flash *flash = to_sst25l_flash(mtd);
176	uint32_t addr, end;
177	int err;
178
179	/* Sanity checks */
180	if (instr->addr + instr->len > flash->mtd.size)
181	return -EINVAL;
182
183	if ((uint32_t)instr->len % mtd->erasesize)
184	return -EINVAL;
185
186	if ((uint32_t)instr->addr % mtd->erasesize)
187	return -EINVAL;
188
189	addr = instr->addr;
190	end = addr + instr->len;
191
192	mutex_lock(&flash->lock);
193
194	err = sst25l_wait_till_ready(flash);
2eaaa5ff JS	195	if (err) {
2eaaa5ff JS	196	mutex_unlock(&flash->lock);
ec77e21b	197	return err;
2eaaa5ff	198	}
ec77e21b RM	199
	200	while (addr < end) {
	201	err = sst25l_erase_sector(flash, addr);
	202	if (err) {
	203	mutex_unlock(&flash->lock);
	204	instr->state = MTD_ERASE_FAILED;
	205	dev_err(&flash->spi->dev, "Erase failed\n");
	206	return err;
	207	}
	208
	209	addr += mtd->erasesize;
	210	}
	211
	212	mutex_unlock(&flash->lock);
	213
	214	instr->state = MTD_ERASE_DONE;
	215	mtd_erase_callback(instr);
	216	return 0;
	217	}
	218
	219	static int sst25l_read(struct mtd_info *mtd, loff_t from, size_t len,
	220	size_t retlen, unsigned char buf)
	221	{
	222	struct sst25l_flash *flash = to_sst25l_flash(mtd);
	223	struct spi_transfer transfer[2];
	224	struct spi_message message;
	225	unsigned char command[4];
	226	int ret;
	227
	228	/* Sanity checking */
	229	if (len == 0)
	230	return 0;
	231
	232	if (from + len > flash->mtd.size)
	233	return -EINVAL;
	234
	235	if (retlen)
	236	*retlen = 0;
	237
	238	spi_message_init(&message);
	239	memset(&transfer, 0, sizeof(transfer));
	240
	241	command[0] = SST25L_CMD_READ;
	242	command[1] = from >> 16;
	243	command[2] = from >> 8;
	244	command[3] = from;
	245
	246	transfer[0].tx_buf = command;
	247	transfer[0].len = sizeof(command);
	248	spi_message_add_tail(&transfer[0], &message);
	249
	250	transfer[1].rx_buf = buf;
	251	transfer[1].len = len;
	252	spi_message_add_tail(&transfer[1], &message);
	253
	254	mutex_lock(&flash->lock);
	255
	256	/* Wait for previous write/erase to complete */
	257	ret = sst25l_wait_till_ready(flash);
	258	if (ret) {
	259	mutex_unlock(&flash->lock);
	260	return ret;
	261	}
	262
263	spi_sync(flash->spi, &message);
264
265	if (retlen && message.actual_length > sizeof(command))
266	*retlen += message.actual_length - sizeof(command);
267
268	mutex_unlock(&flash->lock);
269	return 0;
270	}
271
272	static int sst25l_write(struct mtd_info *mtd, loff_t to, size_t len,
273	size_t retlen, const unsigned char buf)
274	{
275	struct sst25l_flash *flash = to_sst25l_flash(mtd);
276	int i, j, ret, bytes, copied = 0;
277	unsigned char command[5];
278
279	/* Sanity checks */
280	if (!len)
281	return 0;
282
283	if (to + len > flash->mtd.size)
284	return -EINVAL;
285
286	if ((uint32_t)to % mtd->writesize)
287	return -EINVAL;
288
289	mutex_lock(&flash->lock);
290
291	ret = sst25l_write_enable(flash, 1);
292	if (ret)
293	goto out;
294
295	for (i = 0; i < len; i += mtd->writesize) {
296	ret = sst25l_wait_till_ready(flash);
297	if (ret)
298	goto out;
299
300	/* Write the first byte of the page */
301	command[0] = SST25L_CMD_AAI_PROGRAM;
302	command[1] = (to + i) >> 16;
303	command[2] = (to + i) >> 8;
304	command[3] = (to + i);
305	command[4] = buf[i];
306	ret = spi_write(flash->spi, command, 5);
307	if (ret < 0)
308	goto out;
309	copied++;
310
311	/*
312	* Write the remaining bytes using auto address
313	* increment mode
314	*/
315	bytes = min_t(uint32_t, mtd->writesize, len - i);
316	for (j = 1; j < bytes; j++, copied++) {
317	ret = sst25l_wait_till_ready(flash);
318	if (ret)
319	goto out;
320
321	command[1] = buf[i + j];
322	ret = spi_write(flash->spi, command, 2);
323	if (ret)
324	goto out;
325	}
326	}
327
328	out:
329	ret = sst25l_write_enable(flash, 0);
330
331	if (retlen)
332	*retlen = copied;
333
334	mutex_unlock(&flash->lock);
335	return ret;
336	}
337
6b2995b6	338	static struct flash_info __devinit sst25l_match_device(struct spi_device spi)
ec77e21b RM	339	{
ec77e21b RM	340	struct flash_info *flash_info = NULL;
0ffe0ce3 HS	341	struct spi_message m;
	342	struct spi_transfer t;
	343	unsigned char cmd_resp[6];
ec77e21b RM	344	int i, err;
	345	uint16_t id;
	346
0ffe0ce3 HS	347	spi_message_init(&m);
	348	memset(&t, 0, sizeof(struct spi_transfer));
	349
	350	cmd_resp[0] = SST25L_CMD_READ_ID;
	351	cmd_resp[1] = 0;
	352	cmd_resp[2] = 0;
	353	cmd_resp[3] = 0;
	354	cmd_resp[4] = 0xff;
	355	cmd_resp[5] = 0xff;
	356	t.tx_buf = cmd_resp;
	357	t.rx_buf = cmd_resp;
	358	t.len = sizeof(cmd_resp);
	359	spi_message_add_tail(&t, &m);
	360	err = spi_sync(spi, &m);
ec77e21b	361	if (err < 0) {
0ffe0ce3	362	dev_err(&spi->dev, "error reading device id\n");
ec77e21b RM	363	return NULL;
	364	}
	365
0ffe0ce3	366	id = (cmd_resp[4] << 8) \| cmd_resp[5];
ec77e21b RM	367
	368	for (i = 0; i < ARRAY_SIZE(sst25l_flash_info); i++)
	369	if (sst25l_flash_info[i].device_id == id)
	370	flash_info = &sst25l_flash_info[i];
	371
	372	if (!flash_info)
	373	dev_err(&spi->dev, "unknown id %.4x\n", id);
	374
	375	return flash_info;
	376	}
	377
6b2995b6	378	static int __devinit sst25l_probe(struct spi_device *spi)
ec77e21b RM	379	{
	380	struct flash_info *flash_info;
	381	struct sst25l_flash *flash;
	382	struct flash_platform_data *data;
	383	int ret, i;
98b3979b JI	384	struct mtd_partition *parts = NULL;
98b3979b JI	385	int nr_parts = 0;
ec77e21b RM	386
	387	flash_info = sst25l_match_device(spi);
	388	if (!flash_info)
	389	return -ENODEV;
	390
	391	flash = kzalloc(sizeof(struct sst25l_flash), GFP_KERNEL);
	392	if (!flash)
	393	return -ENOMEM;
	394
	395	flash->spi = spi;
	396	mutex_init(&flash->lock);
	397	dev_set_drvdata(&spi->dev, flash);
	398
	399	data = spi->dev.platform_data;
	400	if (data && data->name)
	401	flash->mtd.name = data->name;
	402	else
	403	flash->mtd.name = dev_name(&spi->dev);
	404
	405	flash->mtd.type = MTD_NORFLASH;
	406	flash->mtd.flags = MTD_CAP_NORFLASH;
	407	flash->mtd.erasesize = flash_info->erase_size;
	408	flash->mtd.writesize = flash_info->page_size;
	409	flash->mtd.size = flash_info->page_size * flash_info->nr_pages;
	410	flash->mtd.erase = sst25l_erase;
	411	flash->mtd.read = sst25l_read;
	412	flash->mtd.write = sst25l_write;
	413
	414	dev_info(&spi->dev, "%s (%lld KiB)\n", flash_info->name,
	415	(long long)flash->mtd.size >> 10);
	416
	417	DEBUG(MTD_DEBUG_LEVEL2,
	418	"mtd .name = %s, .size = 0x%llx (%lldMiB) "
	419	".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n",
	420	flash->mtd.name,
	421	(long long)flash->mtd.size, (long long)(flash->mtd.size >> 20),
	422	flash->mtd.erasesize, flash->mtd.erasesize / 1024,
	423	flash->mtd.numeraseregions);
	424
ec77e21b	425
98b3979b JI	426	if (mtd_has_cmdlinepart()) {
98b3979b JI	427	static const char *part_probes[] = {"cmdlinepart", NULL};
ec77e21b	428
98b3979b JI	429	nr_parts = parse_mtd_partitions(&flash->mtd,
	430	part_probes,
	431	&parts, 0);
	432	}
ec77e21b	433
98b3979b JI	434	if (nr_parts <= 0 && data && data->parts) {
	435	parts = data->parts;
	436	nr_parts = data->nr_parts;
	437	}
ec77e21b	438
98b3979b JI	439	if (nr_parts > 0) {
	440	for (i = 0; i < nr_parts; i++) {
	441	DEBUG(MTD_DEBUG_LEVEL2, "partitions[%d] = "
	442	"{.name = %s, .offset = 0x%llx, "
	443	".size = 0x%llx (%lldKiB) }\n",
	444	i, parts[i].name,
	445	(long long)parts[i].offset,
	446	(long long)parts[i].size,
	447	(long long)(parts[i].size >> 10));
ec77e21b RM	448	}
ec77e21b RM	449
98b3979b JI	450	flash->partitioned = 1;
	451	return mtd_device_register(&flash->mtd, parts,
	452	nr_parts);
ec77e21b RM	453	}
ec77e21b RM	454
98b3979b	455	ret = mtd_device_register(&flash->mtd, NULL, 0);
ec77e21b RM	456	if (ret == 1) {
	457	kfree(flash);
	458	dev_set_drvdata(&spi->dev, NULL);
	459	return -ENODEV;
	460	}
	461
	462	return 0;
	463	}
	464
61cc8276	465	static int __devexit sst25l_remove(struct spi_device *spi)
ec77e21b RM	466	{
	467	struct sst25l_flash *flash = dev_get_drvdata(&spi->dev);
	468	int ret;
	469
98b3979b	470	ret = mtd_device_unregister(&flash->mtd);
ec77e21b RM	471	if (ret == 0)
	472	kfree(flash);
	473	return ret;
	474	}
	475
	476	static struct spi_driver sst25l_driver = {
	477	.driver = {
	478	.name = "sst25l",
	479	.bus = &spi_bus_type,
	480	.owner = THIS_MODULE,
	481	},
	482	.probe = sst25l_probe,
61cc8276	483	.remove = __devexit_p(sst25l_remove),
ec77e21b RM	484	};
	485
	486	static int __init sst25l_init(void)
	487	{
	488	return spi_register_driver(&sst25l_driver);
	489	}
	490
	491	static void __exit sst25l_exit(void)
	492	{
	493	spi_unregister_driver(&sst25l_driver);
	494	}
	495
	496	module_init(sst25l_init);
	497	module_exit(sst25l_exit);
	498
	499	MODULE_DESCRIPTION("MTD SPI driver for SST25L Flash chips");
	500	MODULE_AUTHOR("Andre Renaud <andre@bluewatersys.com>, "
	501	"Ryan Mallon <ryan@bluewatersys.com>");
	502	MODULE_LICENSE("GPL");