2 * MTD SPI driver for ST M25Pxx (and similar) serial flash chips
4 * Author: Mike Lavender, mike@steroidmicros.com
6 * Copyright (c) 2005, Intec Automation Inc.
8 * Some parts are based on lart.c by Abraham Van Der Merwe
10 * Cleaned up and generalized based on mtd_dataflash.c
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.
18 #include <linux/err.h>
19 #include <linux/errno.h>
20 #include <linux/module.h>
21 #include <linux/device.h>
23 #include <linux/mtd/mtd.h>
24 #include <linux/mtd/partitions.h>
26 #include <linux/spi/spi.h>
27 #include <linux/spi/flash.h>
28 #include <linux/mtd/spi-nor.h>
30 #define MAX_CMD_SIZE 6
32 struct spi_device
*spi
;
33 struct spi_nor spi_nor
;
34 u8 command
[MAX_CMD_SIZE
];
37 static int m25p80_read_reg(struct spi_nor
*nor
, u8 code
, u8
*val
, int len
)
39 struct m25p
*flash
= nor
->priv
;
40 struct spi_device
*spi
= flash
->spi
;
43 ret
= spi_write_then_read(spi
, &code
, 1, val
, len
);
45 dev_err(&spi
->dev
, "error %d reading %x\n", ret
, code
);
50 static void m25p_addr2cmd(struct spi_nor
*nor
, unsigned int addr
, u8
*cmd
)
52 /* opcode is in cmd[0] */
53 cmd
[1] = addr
>> (nor
->addr_width
* 8 - 8);
54 cmd
[2] = addr
>> (nor
->addr_width
* 8 - 16);
55 cmd
[3] = addr
>> (nor
->addr_width
* 8 - 24);
56 cmd
[4] = addr
>> (nor
->addr_width
* 8 - 32);
59 static int m25p_cmdsz(struct spi_nor
*nor
)
61 return 1 + nor
->addr_width
;
64 static int m25p80_write_reg(struct spi_nor
*nor
, u8 opcode
, u8
*buf
, int len
)
66 struct m25p
*flash
= nor
->priv
;
67 struct spi_device
*spi
= flash
->spi
;
69 flash
->command
[0] = opcode
;
71 memcpy(&flash
->command
[1], buf
, len
);
73 return spi_write(spi
, flash
->command
, len
+ 1);
76 static ssize_t
m25p80_write(struct spi_nor
*nor
, loff_t to
, size_t len
,
79 struct m25p
*flash
= nor
->priv
;
80 struct spi_device
*spi
= flash
->spi
;
81 struct spi_transfer t
[2] = {};
83 int cmd_sz
= m25p_cmdsz(nor
);
88 if (nor
->program_opcode
== SPINOR_OP_AAI_WP
&& nor
->sst_write_second
)
91 flash
->command
[0] = nor
->program_opcode
;
92 m25p_addr2cmd(nor
, to
, flash
->command
);
94 t
[0].tx_buf
= flash
->command
;
96 spi_message_add_tail(&t
[0], &m
);
100 spi_message_add_tail(&t
[1], &m
);
102 ret
= spi_sync(spi
, &m
);
106 ret
= m
.actual_length
- cmd_sz
;
112 static inline unsigned int m25p80_rx_nbits(struct spi_nor
*nor
)
114 switch (nor
->flash_read
) {
125 * Read an address range from the nor chip. The address range
126 * may be any size provided it is within the physical boundaries.
128 static ssize_t
m25p80_read(struct spi_nor
*nor
, loff_t from
, size_t len
,
131 struct m25p
*flash
= nor
->priv
;
132 struct spi_device
*spi
= flash
->spi
;
133 struct spi_transfer t
[2];
134 struct spi_message m
;
135 unsigned int dummy
= nor
->read_dummy
;
138 /* convert the dummy cycles to the number of bytes */
141 if (spi_flash_read_supported(spi
)) {
142 struct spi_flash_read_message msg
;
144 memset(&msg
, 0, sizeof(msg
));
149 msg
.read_opcode
= nor
->read_opcode
;
150 msg
.addr_width
= nor
->addr_width
;
151 msg
.dummy_bytes
= dummy
;
152 /* TODO: Support other combinations */
153 msg
.opcode_nbits
= SPI_NBITS_SINGLE
;
154 msg
.addr_nbits
= SPI_NBITS_SINGLE
;
155 msg
.data_nbits
= m25p80_rx_nbits(nor
);
157 ret
= spi_flash_read(spi
, &msg
);
163 spi_message_init(&m
);
164 memset(t
, 0, (sizeof t
));
166 flash
->command
[0] = nor
->read_opcode
;
167 m25p_addr2cmd(nor
, from
, flash
->command
);
169 t
[0].tx_buf
= flash
->command
;
170 t
[0].len
= m25p_cmdsz(nor
) + dummy
;
171 spi_message_add_tail(&t
[0], &m
);
174 t
[1].rx_nbits
= m25p80_rx_nbits(nor
);
175 t
[1].len
= min(len
, spi_max_transfer_size(spi
));
176 spi_message_add_tail(&t
[1], &m
);
178 ret
= spi_sync(spi
, &m
);
182 ret
= m
.actual_length
- m25p_cmdsz(nor
) - dummy
;
189 * board specific setup should have ensured the SPI clock used here
190 * matches what the READ command supports, at least until this driver
191 * understands FAST_READ (for clocks over 25 MHz).
193 static int m25p_probe(struct spi_device
*spi
)
195 struct flash_platform_data
*data
;
198 enum read_mode mode
= SPI_NOR_NORMAL
;
202 data
= dev_get_platdata(&spi
->dev
);
204 flash
= devm_kzalloc(&spi
->dev
, sizeof(*flash
), GFP_KERNEL
);
208 nor
= &flash
->spi_nor
;
210 /* install the hooks */
211 nor
->read
= m25p80_read
;
212 nor
->write
= m25p80_write
;
213 nor
->write_reg
= m25p80_write_reg
;
214 nor
->read_reg
= m25p80_read_reg
;
216 nor
->dev
= &spi
->dev
;
217 spi_nor_set_flash_node(nor
, spi
->dev
.of_node
);
220 spi_set_drvdata(spi
, flash
);
223 if (spi
->mode
& SPI_RX_QUAD
)
225 else if (spi
->mode
& SPI_RX_DUAL
)
228 if (data
&& data
->name
)
229 nor
->mtd
.name
= data
->name
;
231 /* For some (historical?) reason many platforms provide two different
232 * names in flash_platform_data: "name" and "type". Quite often name is
233 * set to "m25p80" and then "type" provides a real chip name.
234 * If that's the case, respect "type" and ignore a "name".
236 if (data
&& data
->type
)
237 flash_name
= data
->type
;
238 else if (!strcmp(spi
->modalias
, "spi-nor"))
239 flash_name
= NULL
; /* auto-detect */
241 flash_name
= spi
->modalias
;
243 ret
= spi_nor_scan(nor
, flash_name
, mode
);
247 return mtd_device_register(&nor
->mtd
, data
? data
->parts
: NULL
,
248 data
? data
->nr_parts
: 0);
252 static int m25p_remove(struct spi_device
*spi
)
254 struct m25p
*flash
= spi_get_drvdata(spi
);
256 /* Clean up MTD stuff. */
257 return mtd_device_unregister(&flash
->spi_nor
.mtd
);
261 * Do NOT add to this array without reading the following:
263 * Historically, many flash devices are bound to this driver by their name. But
264 * since most of these flash are compatible to some extent, and their
265 * differences can often be differentiated by the JEDEC read-ID command, we
266 * encourage new users to add support to the spi-nor library, and simply bind
267 * against a generic string here (e.g., "jedec,spi-nor").
269 * Many flash names are kept here in this list (as well as in spi-nor.c) to
270 * keep them available as module aliases for existing platforms.
272 static const struct spi_device_id m25p_ids
[] = {
274 * Allow non-DT platform devices to bind to the "spi-nor" modalias, and
275 * hack around the fact that the SPI core does not provide uevent
276 * matching for .of_match_table
281 * Entries not used in DTs that should be safe to drop after replacing
282 * them with "spi-nor" in platform data.
284 {"s25sl064a"}, {"w25x16"}, {"m25p10"}, {"m25px64"},
287 * Entries that were used in DTs without "jedec,spi-nor" fallback and
288 * should be kept for backward compatibility.
290 {"at25df321a"}, {"at25df641"}, {"at26df081a"},
292 {"mx25l4005a"}, {"mx25l1606e"}, {"mx25l6405d"}, {"mx25l12805d"},
293 {"mx25l25635e"},{"mx66l51235l"},
294 {"n25q064"}, {"n25q128a11"}, {"n25q128a13"}, {"n25q512a"},
295 {"s25fl256s1"}, {"s25fl512s"}, {"s25sl12801"}, {"s25fl008k"},
297 {"sst25vf040b"},{"sst25vf016b"},{"sst25vf032b"},{"sst25wf040"},
298 {"m25p40"}, {"m25p80"}, {"m25p16"}, {"m25p32"},
299 {"m25p64"}, {"m25p128"},
300 {"w25x80"}, {"w25x32"}, {"w25q32"}, {"w25q32dw"},
301 {"w25q80bl"}, {"w25q128"}, {"w25q256"},
303 /* Flashes that can't be detected using JEDEC */
304 {"m25p05-nonjedec"}, {"m25p10-nonjedec"}, {"m25p20-nonjedec"},
305 {"m25p40-nonjedec"}, {"m25p80-nonjedec"}, {"m25p16-nonjedec"},
306 {"m25p32-nonjedec"}, {"m25p64-nonjedec"}, {"m25p128-nonjedec"},
310 MODULE_DEVICE_TABLE(spi
, m25p_ids
);
312 static const struct of_device_id m25p_of_table
[] = {
314 * Generic compatibility for SPI NOR that can be identified by the
315 * JEDEC READ ID opcode (0x9F). Use this, if possible.
317 { .compatible
= "jedec,spi-nor" },
320 MODULE_DEVICE_TABLE(of
, m25p_of_table
);
322 static struct spi_driver m25p80_driver
= {
325 .of_match_table
= m25p_of_table
,
327 .id_table
= m25p_ids
,
329 .remove
= m25p_remove
,
331 /* REVISIT: many of these chips have deep power-down modes, which
332 * should clearly be entered on suspend() to minimize power use.
333 * And also when they're otherwise idle...
337 module_spi_driver(m25p80_driver
);
339 MODULE_LICENSE("GPL");
340 MODULE_AUTHOR("Mike Lavender");
341 MODULE_DESCRIPTION("MTD SPI driver for ST M25Pxx flash chips");