aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/mtd/devices/m25p80.c
blob: 7c8b1694a134da91cbeb5b4764922c8e7d8d06c2 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
/*
 * MTD SPI driver for ST M25Pxx (and similar) serial flash chips
 *
 * Author: Mike Lavender, mike@steroidmicros.com
 *
 * Copyright (c) 2005, Intec Automation Inc.
 *
 * Some parts are based on lart.c by Abraham Van Der Merwe
 *
 * Cleaned up and generalized based on mtd_dataflash.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/err.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/device.h>

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

#include <linux/spi/spi.h>
#include <linux/spi/flash.h>
#include <linux/mtd/spi-nor.h>

#define	MAX_CMD_SIZE		6
struct m25p {
	struct spi_device	*spi;
	struct spi_nor		spi_nor;
	struct mtd_info		mtd;
	u8			command[MAX_CMD_SIZE];
};

static int m25p80_read_reg(struct spi_nor *nor, u8 code, u8 *val, int len)
{
	struct m25p *flash = nor->priv;
	struct spi_device *spi = flash->spi;
	int ret;

	ret = spi_write_then_read(spi, &code, 1, val, len);
	if (ret < 0)
		dev_err(&spi->dev, "error %d reading %x\n", ret, code);

	return ret;
}

static void m25p_addr2cmd(struct spi_nor *nor, unsigned int addr, u8 *cmd)
{
	/* opcode is in cmd[0] */
	cmd[1] = addr >> (nor->addr_width * 8 -  8);
	cmd[2] = addr >> (nor->addr_width * 8 - 16);
	cmd[3] = addr >> (nor->addr_width * 8 - 24);
	cmd[4] = addr >> (nor->addr_width * 8 - 32);
}

static int m25p_cmdsz(struct spi_nor *nor)
{
	return 1 + nor->addr_width;
}

static int m25p80_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len,
			int wr_en)
{
	struct m25p *flash = nor->priv;
	struct spi_device *spi = flash->spi;

	flash->command[0] = opcode;
	if (buf)
		memcpy(&flash->command[1], buf, len);

	return spi_write(spi, flash->command, len + 1);
}

static void m25p80_write(struct spi_nor *nor, loff_t to, size_t len,
			size_t *retlen, const u_char *buf)
{
	struct m25p *flash = nor->priv;
	struct spi_device *spi = flash->spi;
	struct spi_transfer t[2] = {};
	struct spi_message m;
	int cmd_sz = m25p_cmdsz(nor);

	spi_message_init(&m);

	if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
		cmd_sz = 1;

	flash->command[0] = nor->program_opcode;
	m25p_addr2cmd(nor, to, flash->command);

	t[0].tx_buf = flash->command;
	t[0].len = cmd_sz;
	spi_message_add_tail(&t[0], &m);

	t[1].tx_buf = buf;
	t[1].len = len;
	spi_message_add_tail(&t[1], &m);

	spi_sync(spi, &m);

	*retlen += m.actual_length - cmd_sz;
}

static inline unsigned int m25p80_rx_nbits(struct spi_nor *nor)
{
	switch (nor->flash_read) {
	case SPI_NOR_DUAL:
		return 2;
	case SPI_NOR_QUAD:
		return 4;
	default:
		return 0;
	}
}

/*
 * Read an address range from the nor chip.  The address range
 * may be any size provided it is within the physical boundaries.
 */
static int m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
			size_t *retlen, u_char *buf)
{
	struct m25p *flash = nor->priv;
	struct spi_device *spi = flash->spi;
	struct spi_transfer t[2];
	struct spi_message m;
	unsigned int dummy = nor->read_dummy;

	/* convert the dummy cycles to the number of bytes */
	dummy /= 8;

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

	flash->command[0] = nor->read_opcode;
	m25p_addr2cmd(nor, from, flash->command);

	t[0].tx_buf = flash->command;
	t[0].len = m25p_cmdsz(nor) + dummy;
	spi_message_add_tail(&t[0], &m);

	t[1].rx_buf = buf;
	t[1].rx_nbits = m25p80_rx_nbits(nor);
	t[1].len = len;
	spi_message_add_tail(&t[1], &m);

	spi_sync(spi, &m);

	*retlen = m.actual_length - m25p_cmdsz(nor) - dummy;
	return 0;
}

static int m25p80_erase(struct spi_nor *nor, loff_t offset)
{
	struct m25p *flash = nor->priv;

	dev_dbg(nor->dev, "%dKiB at 0x%08x\n",
		flash->mtd.erasesize / 1024, (u32)offset);

	/* Set up command buffer. */
	flash->command[0] = nor->erase_opcode;
	m25p_addr2cmd(nor, offset, flash->command);

	spi_write(flash->spi, flash->command, m25p_cmdsz(nor));

	return 0;
}

/*
 * board specific setup should have ensured the SPI clock used here
 * matches what the READ command supports, at least until this driver
 * understands FAST_READ (for clocks over 25 MHz).
 */
static int m25p_probe(struct spi_device *spi)
{
	struct mtd_part_parser_data	ppdata;
	struct flash_platform_data	*data;
	struct m25p *flash;
	struct spi_nor *nor;
	enum read_mode mode = SPI_NOR_NORMAL;
	char *flash_name = NULL;
	int ret;

	data = dev_get_platdata(&spi->dev);

	flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL);
	if (!flash)
		return -ENOMEM;

	nor = &flash->spi_nor;

	/* install the hooks */
	nor->read = m25p80_read;
	nor->write = m25p80_write;
	nor->erase = m25p80_erase;
	nor->write_reg = m25p80_write_reg;
	nor->read_reg = m25p80_read_reg;

	nor->dev = &spi->dev;
	nor->mtd = &flash->mtd;
	nor->priv = flash;

	spi_set_drvdata(spi, flash);
	flash->mtd.priv = nor;
	flash->spi = spi;

	if (spi->mode & SPI_RX_QUAD)
		mode = SPI_NOR_QUAD;
	else if (spi->mode & SPI_RX_DUAL)
		mode = SPI_NOR_DUAL;

	if (data && data->name)
		flash->mtd.name = data->name;

	/* For some (historical?) reason many platforms provide two different
	 * names in flash_platform_data: "name" and "type". Quite often name is
	 * set to "m25p80" and then "type" provides a real chip name.
	 * If that's the case, respect "type" and ignore a "name".
	 */
	if (data && data->type)
		flash_name = data->type;
	else if (!strcmp(spi->modalias, "nor-jedec"))
		flash_name = NULL; /* auto-detect */
	else
		flash_name = spi->modalias;

	ret = spi_nor_scan(nor, flash_name, mode);
	if (ret)
		return ret;

	ppdata.of_node = spi->dev.of_node;

	return mtd_device_parse_register(&flash->mtd, NULL, &ppdata,
			data ? data->parts : NULL,
			data ? data->nr_parts : 0);
}


static int m25p_remove(struct spi_device *spi)
{
	struct m25p	*flash = spi_get_drvdata(spi);

	/* Clean up MTD stuff. */
	return mtd_device_unregister(&flash->mtd);
}

/*
 * Do NOT add to this array without reading the following:
 *
 * Historically, many flash devices are bound to this driver by their name. But
 * since most of these flash are compatible to some extent, and their
 * differences can often be differentiated by the JEDEC read-ID command, we
 * encourage new users to add support to the spi-nor library, and simply bind
 * against a generic string here (e.g., "nor-jedec").
 *
 * Many flash names are kept here in this list (as well as in spi-nor.c) to
 * keep them available as module aliases for existing platforms.
 */
static const struct spi_device_id m25p_ids[] = {
	{"at25fs010"},	{"at25fs040"},	{"at25df041a"},	{"at25df321a"},
	{"at25df641"},	{"at26f004"},	{"at26df081a"},	{"at26df161a"},
	{"at26df321"},	{"at45db081d"},
	{"en25f32"},	{"en25p32"},	{"en25q32b"},	{"en25p64"},
	{"en25q64"},	{"en25qh128"},	{"en25qh256"},
	{"f25l32pa"},
	{"mr25h256"},	{"mr25h10"},
	{"gd25q32"},	{"gd25q64"},
	{"160s33b"},	{"320s33b"},	{"640s33b"},
	{"mx25l2005a"},	{"mx25l4005a"},	{"mx25l8005"},	{"mx25l1606e"},
	{"mx25l3205d"},	{"mx25l3255e"},	{"mx25l6405d"},	{"mx25l12805d"},
	{"mx25l12855e"},{"mx25l25635e"},{"mx25l25655e"},{"mx66l51235l"},
	{"mx66l1g55g"},
	{"n25q064"},	{"n25q128a11"},	{"n25q128a13"},	{"n25q256a"},
	{"n25q512a"},	{"n25q512ax3"},	{"n25q00"},
	{"pm25lv512"},	{"pm25lv010"},	{"pm25lq032"},
	{"s25sl032p"},	{"s25sl064p"},	{"s25fl256s0"},	{"s25fl256s1"},
	{"s25fl512s"},	{"s70fl01gs"},	{"s25sl12800"},	{"s25sl12801"},
	{"s25fl129p0"},	{"s25fl129p1"},	{"s25sl004a"},	{"s25sl008a"},
	{"s25sl016a"},	{"s25sl032a"},	{"s25sl064a"},	{"s25fl008k"},
	{"s25fl016k"},	{"s25fl064k"},	{"s25fl132k"},
	{"sst25vf040b"},{"sst25vf080b"},{"sst25vf016b"},{"sst25vf032b"},
	{"sst25vf064c"},{"sst25wf512"},	{"sst25wf010"},	{"sst25wf020"},
	{"sst25wf040"},
	{"m25p05"},	{"m25p10"},	{"m25p20"},	{"m25p40"},
	{"m25p80"},	{"m25p16"},	{"m25p32"},	{"m25p64"},
	{"m25p128"},	{"n25q032"},
	{"m25p05-nonjedec"},	{"m25p10-nonjedec"},	{"m25p20-nonjedec"},
	{"m25p40-nonjedec"},	{"m25p80-nonjedec"},	{"m25p16-nonjedec"},
	{"m25p32-nonjedec"},	{"m25p64-nonjedec"},	{"m25p128-nonjedec"},
	{"m45pe10"},	{"m45pe80"},	{"m45pe16"},
	{"m25pe20"},	{"m25pe80"},	{"m25pe16"},
	{"m25px16"},	{"m25px32"},	{"m25px32-s0"},	{"m25px32-s1"},
	{"m25px64"},	{"m25px80"},
	{"w25x10"},	{"w25x20"},	{"w25x40"},	{"w25x80"},
	{"w25x16"},	{"w25x32"},	{"w25q32"},	{"w25q32dw"},
	{"w25x64"},	{"w25q64"},	{"w25q80"},	{"w25q80bl"},
	{"w25q128"},	{"w25q256"},	{"cat25c11"},
	{"cat25c03"},	{"cat25c09"},	{"cat25c17"},	{"cat25128"},

	/*
	 * Generic support for SPI NOR that can be identified by the JEDEC READ
	 * ID opcode (0x9F). Use this, if possible.
	 */
	{"nor-jedec"},
	{ },
};
MODULE_DEVICE_TABLE(spi, m25p_ids);

static struct spi_driver m25p80_driver = {
	.driver = {
		.name	= "m25p80",
		.owner	= THIS_MODULE,
	},
	.id_table	= m25p_ids,
	.probe	= m25p_probe,
	.remove	= m25p_remove,

	/* REVISIT: many of these chips have deep power-down modes, which
	 * should clearly be entered on suspend() to minimize power use.
	 * And also when they're otherwise idle...
	 */
};

module_spi_driver(m25p80_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mike Lavender");
MODULE_DESCRIPTION("MTD SPI driver for ST M25Pxx flash chips");