[deliverable/linux.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/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 __initdata sst25l_flash_info[] = {
	{"sst25lf020a", 0xbf43, 256, 1024, 4096},
	{"sst25lf040a",	0xbf44,	256, 2048, 4096},
};

static int sst25l_status(struct sst25l_flash *flash, int *status)
{
	unsigned char command, response;
	int err;

	command = SST25L_CMD_RDSR;
	err = spi_write_then_read(flash->spi, &command, 1, &response, 1);
	if (err < 0)
		return err;

	*status = response;
	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 *__init sst25l_match_device(struct spi_device *spi)
{
	struct flash_info *flash_info = NULL;
	unsigned char command[4], response;
	int i, err;
	uint16_t id;

	command[0] = SST25L_CMD_READ_ID;
	command[1] = 0;
	command[2] = 0;
	command[3] = 0;
	err = spi_write_then_read(spi, command, sizeof(command), &response, 1);
	if (err < 0) {
		dev_err(&spi->dev, "error reading device id msb\n");
		return NULL;
	}

	id = response << 8;

	command[0] = SST25L_CMD_READ_ID;
	command[1] = 0;
	command[2] = 0;
	command[3] = 1;
	err = spi_write_then_read(spi, command, sizeof(command), &response, 1);
	if (err < 0) {
		dev_err(&spi->dev, "error reading device id lsb\n");
		return NULL;
	}

	id |= response;

	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 __init sst25l_probe(struct spi_device *spi)
{
	struct flash_info *flash_info;
	struct sst25l_flash *flash;
	struct flash_platform_data *data;
	int ret, i;

	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 (flash->mtd.numeraseregions)
		for (i = 0; i < flash->mtd.numeraseregions; i++)
			DEBUG(MTD_DEBUG_LEVEL2,
			      "mtd.eraseregions[%d] = { .offset = 0x%llx, "
			      ".erasesize = 0x%.8x (%uKiB), "
			      ".numblocks = %d }\n",
			      i, (long long)flash->mtd.eraseregions[i].offset,
			      flash->mtd.eraseregions[i].erasesize,
			      flash->mtd.eraseregions[i].erasesize / 1024,
			      flash->mtd.eraseregions[i].numblocks);

	if (mtd_has_partitions()) {
		struct mtd_partition *parts = NULL;
		int nr_parts = 0;

		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 add_mtd_partitions(&flash->mtd,
						  parts, nr_parts);
		}

	} else if (data->nr_parts) {
		dev_warn(&spi->dev, "ignoring %d default partitions on %s\n",
			 data->nr_parts, data->name);
	}

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

	return 0;
}

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

	if (mtd_has_partitions() && flash->partitioned)
		ret = del_mtd_partitions(&flash->mtd);
	else
		ret = del_mtd_device(&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		= __exit_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>
d43c36dc	23	#include <linux/sched.h>
ec77e21b RM	24
	25	#include <linux/mtd/mtd.h>
	26	#include <linux/mtd/partitions.h>
	27
	28	#include <linux/spi/spi.h>
	29	#include <linux/spi/flash.h>
	30
	31	/* Erases can take up to 3 seconds! */
	32	#define MAX_READY_WAIT_JIFFIES msecs_to_jiffies(3000)
	33
	34	#define SST25L_CMD_WRSR 0x01 /* Write status register */
	35	#define SST25L_CMD_WRDI 0x04 /* Write disable */
	36	#define SST25L_CMD_RDSR 0x05 /* Read status register */
	37	#define SST25L_CMD_WREN 0x06 /* Write enable */
	38	#define SST25L_CMD_READ 0x03 /* High speed read */
	39
	40	#define SST25L_CMD_EWSR 0x50 /* Enable write status register */
	41	#define SST25L_CMD_SECTOR_ERASE 0x20 /* Erase sector */
	42	#define SST25L_CMD_READ_ID 0x90 /* Read device ID */
	43	#define SST25L_CMD_AAI_PROGRAM 0xaf /* Auto address increment */
	44
	45	#define SST25L_STATUS_BUSY (1 << 0) /* Chip is busy */
	46	#define SST25L_STATUS_WREN (1 << 1) /* Write enabled */
	47	#define SST25L_STATUS_BP0 (1 << 2) /* Block protection 0 */
	48	#define SST25L_STATUS_BP1 (1 << 3) /* Block protection 1 */
	49
	50	struct sst25l_flash {
	51	struct spi_device *spi;
	52	struct mutex lock;
	53	struct mtd_info mtd;
	54
	55	int partitioned;
	56	};
	57
	58	struct flash_info {
	59	const char *name;
	60	uint16_t device_id;
	61	unsigned page_size;
	62	unsigned nr_pages;
	63	unsigned erase_size;
	64	};
	65
	66	#define to_sst25l_flash(x) container_of(x, struct sst25l_flash, mtd)
	67
	68	static struct flash_info __initdata sst25l_flash_info[] = {
	69	{"sst25lf020a", 0xbf43, 256, 1024, 4096},
	70	{"sst25lf040a", 0xbf44, 256, 2048, 4096},
	71	};
	72
	73	static int sst25l_status(struct sst25l_flash flash, int status)
	74	{
	75	unsigned char command, response;
	76	int err;
	77
	78	command = SST25L_CMD_RDSR;
	79	err = spi_write_then_read(flash->spi, &command, 1, &response, 1);
	80	if (err < 0)
	81	return err;
	82
	83	*status = response;
	84	return 0;
	85	}
	86
	87	static int sst25l_write_enable(struct sst25l_flash *flash, int enable)
88	{
89	unsigned char command[2];
90	int status, err;
91
92	command[0] = enable ? SST25L_CMD_WREN : SST25L_CMD_WRDI;
93	err = spi_write(flash->spi, command, 1);
94	if (err)
95	return err;
96
97	command[0] = SST25L_CMD_EWSR;
98	err = spi_write(flash->spi, command, 1);
99	if (err)
100	return err;
101
102	command[0] = SST25L_CMD_WRSR;
103	command[1] = enable ? 0 : SST25L_STATUS_BP0 \| SST25L_STATUS_BP1;
104	err = spi_write(flash->spi, command, 2);
105	if (err)
106	return err;
107
108	if (enable) {
109	err = sst25l_status(flash, &status);
110	if (err)
111	return err;
112	if (!(status & SST25L_STATUS_WREN))
113	return -EROFS;
114	}
115
116	return 0;
117	}
118
119	static int sst25l_wait_till_ready(struct sst25l_flash *flash)
120	{
121	unsigned long deadline;
122	int status, err;
123
124	deadline = jiffies + MAX_READY_WAIT_JIFFIES;
125	do {
126	err = sst25l_status(flash, &status);
127	if (err)
128	return err;
129	if (!(status & SST25L_STATUS_BUSY))
130	return 0;
131
132	cond_resched();
133	} while (!time_after_eq(jiffies, deadline));
134
135	return -ETIMEDOUT;
136	}
137
138	static int sst25l_erase_sector(struct sst25l_flash *flash, uint32_t offset)
139	{
140	unsigned char command[4];
141	int err;
142
143	err = sst25l_write_enable(flash, 1);
144	if (err)
145	return err;
146
147	command[0] = SST25L_CMD_SECTOR_ERASE;
148	command[1] = offset >> 16;
149	command[2] = offset >> 8;
150	command[3] = offset;
151	err = spi_write(flash->spi, command, 4);
152	if (err)
153	return err;
154
155	err = sst25l_wait_till_ready(flash);
156	if (err)
157	return err;
158
159	return sst25l_write_enable(flash, 0);
160	}
161
162	static int sst25l_erase(struct mtd_info mtd, struct erase_info instr)
163	{
164	struct sst25l_flash *flash = to_sst25l_flash(mtd);
165	uint32_t addr, end;
166	int err;
167
168	/* Sanity checks */
169	if (instr->addr + instr->len > flash->mtd.size)
170	return -EINVAL;
171
172	if ((uint32_t)instr->len % mtd->erasesize)
173	return -EINVAL;
174
175	if ((uint32_t)instr->addr % mtd->erasesize)
176	return -EINVAL;
177
178	addr = instr->addr;
179	end = addr + instr->len;
180
181	mutex_lock(&flash->lock);
182
183	err = sst25l_wait_till_ready(flash);
2eaaa5ff JS	184	if (err) {
2eaaa5ff JS	185	mutex_unlock(&flash->lock);
ec77e21b	186	return err;
2eaaa5ff	187	}
ec77e21b RM	188
	189	while (addr < end) {
	190	err = sst25l_erase_sector(flash, addr);
	191	if (err) {
	192	mutex_unlock(&flash->lock);
	193	instr->state = MTD_ERASE_FAILED;
	194	dev_err(&flash->spi->dev, "Erase failed\n");
	195	return err;
	196	}
	197
	198	addr += mtd->erasesize;
	199	}
	200
	201	mutex_unlock(&flash->lock);
	202
	203	instr->state = MTD_ERASE_DONE;
	204	mtd_erase_callback(instr);
	205	return 0;
	206	}
	207
	208	static int sst25l_read(struct mtd_info *mtd, loff_t from, size_t len,
	209	size_t retlen, unsigned char buf)
	210	{
	211	struct sst25l_flash *flash = to_sst25l_flash(mtd);
	212	struct spi_transfer transfer[2];
	213	struct spi_message message;
	214	unsigned char command[4];
	215	int ret;
	216
	217	/* Sanity checking */
	218	if (len == 0)
	219	return 0;
	220
	221	if (from + len > flash->mtd.size)
	222	return -EINVAL;
	223
	224	if (retlen)
	225	*retlen = 0;
	226
	227	spi_message_init(&message);
	228	memset(&transfer, 0, sizeof(transfer));
	229
	230	command[0] = SST25L_CMD_READ;
	231	command[1] = from >> 16;
	232	command[2] = from >> 8;
	233	command[3] = from;
	234
	235	transfer[0].tx_buf = command;
	236	transfer[0].len = sizeof(command);
	237	spi_message_add_tail(&transfer[0], &message);
	238
	239	transfer[1].rx_buf = buf;
	240	transfer[1].len = len;
	241	spi_message_add_tail(&transfer[1], &message);
	242
	243	mutex_lock(&flash->lock);
	244
	245	/* Wait for previous write/erase to complete */
	246	ret = sst25l_wait_till_ready(flash);
	247	if (ret) {
	248	mutex_unlock(&flash->lock);
	249	return ret;
	250	}
	251
252	spi_sync(flash->spi, &message);
253
254	if (retlen && message.actual_length > sizeof(command))
255	*retlen += message.actual_length - sizeof(command);
256
257	mutex_unlock(&flash->lock);
258	return 0;
259	}
260
261	static int sst25l_write(struct mtd_info *mtd, loff_t to, size_t len,
262	size_t retlen, const unsigned char buf)
263	{
264	struct sst25l_flash *flash = to_sst25l_flash(mtd);
265	int i, j, ret, bytes, copied = 0;
266	unsigned char command[5];
267
268	/* Sanity checks */
269	if (!len)
270	return 0;
271
272	if (to + len > flash->mtd.size)
273	return -EINVAL;
274
275	if ((uint32_t)to % mtd->writesize)
276	return -EINVAL;
277
278	mutex_lock(&flash->lock);
279
280	ret = sst25l_write_enable(flash, 1);
281	if (ret)
282	goto out;
283
284	for (i = 0; i < len; i += mtd->writesize) {
285	ret = sst25l_wait_till_ready(flash);
286	if (ret)
287	goto out;
288
289	/* Write the first byte of the page */
290	command[0] = SST25L_CMD_AAI_PROGRAM;
291	command[1] = (to + i) >> 16;
292	command[2] = (to + i) >> 8;
293	command[3] = (to + i);
294	command[4] = buf[i];
295	ret = spi_write(flash->spi, command, 5);
296	if (ret < 0)
297	goto out;
298	copied++;
299
300	/*
301	* Write the remaining bytes using auto address
302	* increment mode
303	*/
304	bytes = min_t(uint32_t, mtd->writesize, len - i);
305	for (j = 1; j < bytes; j++, copied++) {
306	ret = sst25l_wait_till_ready(flash);
307	if (ret)
308	goto out;
309
310	command[1] = buf[i + j];
311	ret = spi_write(flash->spi, command, 2);
312	if (ret)
313	goto out;
314	}
315	}
316
317	out:
318	ret = sst25l_write_enable(flash, 0);
319
320	if (retlen)
321	*retlen = copied;
322
323	mutex_unlock(&flash->lock);
324	return ret;
325	}
326
327	static struct flash_info __init sst25l_match_device(struct spi_device spi)
328	{
329	struct flash_info *flash_info = NULL;
330	unsigned char command[4], response;
331	int i, err;
332	uint16_t id;
333
334	command[0] = SST25L_CMD_READ_ID;
335	command[1] = 0;
336	command[2] = 0;
337	command[3] = 0;
338	err = spi_write_then_read(spi, command, sizeof(command), &response, 1);
339	if (err < 0) {
340	dev_err(&spi->dev, "error reading device id msb\n");
341	return NULL;
342	}
343
344	id = response << 8;
345
346	command[0] = SST25L_CMD_READ_ID;
347	command[1] = 0;
348	command[2] = 0;
349	command[3] = 1;
350	err = spi_write_then_read(spi, command, sizeof(command), &response, 1);
351	if (err < 0) {
352	dev_err(&spi->dev, "error reading device id lsb\n");
353	return NULL;
354	}
355
356	id \|= response;
357
358	for (i = 0; i < ARRAY_SIZE(sst25l_flash_info); i++)
359	if (sst25l_flash_info[i].device_id == id)
360	flash_info = &sst25l_flash_info[i];
361
362	if (!flash_info)
363	dev_err(&spi->dev, "unknown id %.4x\n", id);
364
365	return flash_info;
366	}
367
368	static int __init sst25l_probe(struct spi_device *spi)
369	{
370	struct flash_info *flash_info;
371	struct sst25l_flash *flash;
372	struct flash_platform_data *data;
373	int ret, i;
374
375	flash_info = sst25l_match_device(spi);
376	if (!flash_info)
377	return -ENODEV;
378
379	flash = kzalloc(sizeof(struct sst25l_flash), GFP_KERNEL);
380	if (!flash)
381	return -ENOMEM;
382
383	flash->spi = spi;
384	mutex_init(&flash->lock);
385	dev_set_drvdata(&spi->dev, flash);
386
387	data = spi->dev.platform_data;
388	if (data && data->name)
389	flash->mtd.name = data->name;
390	else
391	flash->mtd.name = dev_name(&spi->dev);
392
393	flash->mtd.type = MTD_NORFLASH;
394	flash->mtd.flags = MTD_CAP_NORFLASH;
395	flash->mtd.erasesize = flash_info->erase_size;
396	flash->mtd.writesize = flash_info->page_size;
397	flash->mtd.size = flash_info->page_size * flash_info->nr_pages;
398	flash->mtd.erase = sst25l_erase;
399	flash->mtd.read = sst25l_read;
400	flash->mtd.write = sst25l_write;
401
402	dev_info(&spi->dev, "%s (%lld KiB)\n", flash_info->name,
403	(long long)flash->mtd.size >> 10);
404
405	DEBUG(MTD_DEBUG_LEVEL2,
406	"mtd .name = %s, .size = 0x%llx (%lldMiB) "
407	".erasesize = 0x%.8x (%uKiB) .numeraseregions = %d\n",
408	flash->mtd.name,
409	(long long)flash->mtd.size, (long long)(flash->mtd.size >> 20),
410	flash->mtd.erasesize, flash->mtd.erasesize / 1024,
411	flash->mtd.numeraseregions);
412
413	if (flash->mtd.numeraseregions)
414	for (i = 0; i < flash->mtd.numeraseregions; i++)
415	DEBUG(MTD_DEBUG_LEVEL2,
416	"mtd.eraseregions[%d] = { .offset = 0x%llx, "
417	".erasesize = 0x%.8x (%uKiB), "
418	".numblocks = %d }\n",
419	i, (long long)flash->mtd.eraseregions[i].offset,
420	flash->mtd.eraseregions[i].erasesize,
421	flash->mtd.eraseregions[i].erasesize / 1024,
422	flash->mtd.eraseregions[i].numblocks);
423
424	if (mtd_has_partitions()) {
425	struct mtd_partition *parts = NULL;
426	int nr_parts = 0;
427
428	if (mtd_has_cmdlinepart()) {
429	static const char *part_probes[] =
430	{"cmdlinepart", NULL};
431
432	nr_parts = parse_mtd_partitions(&flash->mtd,
433	part_probes,
434	&parts, 0);
435	}
436
437	if (nr_parts <= 0 && data && data->parts) {
438	parts = data->parts;
439	nr_parts = data->nr_parts;
440	}
441
442	if (nr_parts > 0) {
443	for (i = 0; i < nr_parts; i++) {
444	DEBUG(MTD_DEBUG_LEVEL2, "partitions[%d] = "
445	"{.name = %s, .offset = 0x%llx, "
446	".size = 0x%llx (%lldKiB) }\n",
447	i, parts[i].name,
448	(long long)parts[i].offset,
449	(long long)parts[i].size,
450	(long long)(parts[i].size >> 10));
451	}
452
453	flash->partitioned = 1;
454	return add_mtd_partitions(&flash->mtd,
455	parts, nr_parts);
456	}
457
458	} else if (data->nr_parts) {
459	dev_warn(&spi->dev, "ignoring %d default partitions on %s\n",
460	data->nr_parts, data->name);
461	}
462
463	ret = add_mtd_device(&flash->mtd);
464	if (ret == 1) {
465	kfree(flash);
466	dev_set_drvdata(&spi->dev, NULL);
467	return -ENODEV;
468	}
469
470	return 0;
471	}
472
473	static int __exit sst25l_remove(struct spi_device *spi)
474	{
475	struct sst25l_flash *flash = dev_get_drvdata(&spi->dev);
476	int ret;
477
478	if (mtd_has_partitions() && flash->partitioned)
479	ret = del_mtd_partitions(&flash->mtd);
480	else
481	ret = del_mtd_device(&flash->mtd);
482	if (ret == 0)
483	kfree(flash);
484	return ret;
485	}
486
487	static struct spi_driver sst25l_driver = {
488	.driver = {
489	.name = "sst25l",
490	.bus = &spi_bus_type,
491	.owner = THIS_MODULE,
492	},
493	.probe = sst25l_probe,
494	.remove = __exit_p(sst25l_remove),
495	};
496
497	static int __init sst25l_init(void)
498	{
499	return spi_register_driver(&sst25l_driver);
500	}
501
502	static void __exit sst25l_exit(void)
503	{
504	spi_unregister_driver(&sst25l_driver);
505	}
506
507	module_init(sst25l_init);
508	module_exit(sst25l_exit);
509
510	MODULE_DESCRIPTION("MTD SPI driver for SST25L Flash chips");
511	MODULE_AUTHOR("Andre Renaud <andre@bluewatersys.com>, "
512	"Ryan Mallon <ryan@bluewatersys.com>");
513	MODULE_LICENSE("GPL");