1 /*
2 * MTD SPI driver for ST M25Pxx (and similar) serial flash chips
3 *
4 * Author: Mike Lavender, mike@steroidmicros.com
5 *
6 * Copyright (c) 2005, Intec Automation Inc.
7 *
8 * Some parts are based on lart.c by Abraham Van Der Merwe
9 *
10 * Cleaned up and generalized based on mtd_dataflash.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/err.h>
19 #include <linux/errno.h>
20 #include <linux/module.h>
21 #include <linux/device.h>
22
23 #include <linux/mtd/mtd.h>
24 #include <linux/mtd/partitions.h>
25
26 #include <linux/spi/spi.h>
27 #include <linux/spi/spi-mem.h>
28 #include <linux/spi/flash.h>
29 #include <linux/mtd/spi-nor.h>
30
31 struct m25p {
32 struct spi_mem *spimem;
33 struct spi_nor spi_nor;
34 };
35
m25p80_read_reg(struct spi_nor * nor,u8 code,u8 * val,int len)36 static int m25p80_read_reg(struct spi_nor *nor, u8 code, u8 *val, int len)
37 {
38 struct m25p *flash = nor->priv;
39 struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(code, 1),
40 SPI_MEM_OP_NO_ADDR,
41 SPI_MEM_OP_NO_DUMMY,
42 SPI_MEM_OP_DATA_IN(len, NULL, 1));
43 void *scratchbuf;
44 int ret;
45
46 scratchbuf = kmalloc(len, GFP_KERNEL);
47 if (!scratchbuf)
48 return -ENOMEM;
49
50 op.data.buf.in = scratchbuf;
51 ret = spi_mem_exec_op(flash->spimem, &op);
52 if (ret < 0)
53 dev_err(&flash->spimem->spi->dev, "error %d reading %x\n", ret,
54 code);
55 else
56 memcpy(val, scratchbuf, len);
57
58 kfree(scratchbuf);
59
60 return ret;
61 }
62
m25p80_write_reg(struct spi_nor * nor,u8 opcode,u8 * buf,int len)63 static int m25p80_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len)
64 {
65 struct m25p *flash = nor->priv;
66 struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(opcode, 1),
67 SPI_MEM_OP_NO_ADDR,
68 SPI_MEM_OP_NO_DUMMY,
69 SPI_MEM_OP_DATA_OUT(len, NULL, 1));
70 void *scratchbuf;
71 int ret;
72
73 scratchbuf = kmemdup(buf, len, GFP_KERNEL);
74 if (!scratchbuf)
75 return -ENOMEM;
76
77 op.data.buf.out = scratchbuf;
78 ret = spi_mem_exec_op(flash->spimem, &op);
79 kfree(scratchbuf);
80
81 return ret;
82 }
83
m25p80_write(struct spi_nor * nor,loff_t to,size_t len,const u_char * buf)84 static ssize_t m25p80_write(struct spi_nor *nor, loff_t to, size_t len,
85 const u_char *buf)
86 {
87 struct m25p *flash = nor->priv;
88 struct spi_mem_op op =
89 SPI_MEM_OP(SPI_MEM_OP_CMD(nor->program_opcode, 1),
90 SPI_MEM_OP_ADDR(nor->addr_width, to, 1),
91 SPI_MEM_OP_NO_DUMMY,
92 SPI_MEM_OP_DATA_OUT(len, buf, 1));
93 size_t remaining = len;
94 int ret;
95
96 /* get transfer protocols. */
97 op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
98 op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
99 op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->write_proto);
100
101 if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
102 op.addr.nbytes = 0;
103
104 while (remaining) {
105 op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX;
106 ret = spi_mem_adjust_op_size(flash->spimem, &op);
107 if (ret)
108 return ret;
109
110 ret = spi_mem_exec_op(flash->spimem, &op);
111 if (ret)
112 return ret;
113
114 op.addr.val += op.data.nbytes;
115 remaining -= op.data.nbytes;
116 op.data.buf.out += op.data.nbytes;
117 }
118
119 return len;
120 }
121
122 /*
123 * Read an address range from the nor chip. The address range
124 * may be any size provided it is within the physical boundaries.
125 */
m25p80_read(struct spi_nor * nor,loff_t from,size_t len,u_char * buf)126 static ssize_t m25p80_read(struct spi_nor *nor, loff_t from, size_t len,
127 u_char *buf)
128 {
129 struct m25p *flash = nor->priv;
130 struct spi_mem_op op =
131 SPI_MEM_OP(SPI_MEM_OP_CMD(nor->read_opcode, 1),
132 SPI_MEM_OP_ADDR(nor->addr_width, from, 1),
133 SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
134 SPI_MEM_OP_DATA_IN(len, buf, 1));
135 size_t remaining = len;
136 int ret;
137
138 /* get transfer protocols. */
139 op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
140 op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->read_proto);
141 op.dummy.buswidth = op.addr.buswidth;
142 op.data.buswidth = spi_nor_get_protocol_data_nbits(nor->read_proto);
143
144 /* convert the dummy cycles to the number of bytes */
145 op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
146
147 while (remaining) {
148 op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX;
149 ret = spi_mem_adjust_op_size(flash->spimem, &op);
150 if (ret)
151 return ret;
152
153 ret = spi_mem_exec_op(flash->spimem, &op);
154 if (ret)
155 return ret;
156
157 op.addr.val += op.data.nbytes;
158 remaining -= op.data.nbytes;
159 op.data.buf.in += op.data.nbytes;
160 }
161
162 return len;
163 }
164
165 /*
166 * board specific setup should have ensured the SPI clock used here
167 * matches what the READ command supports, at least until this driver
168 * understands FAST_READ (for clocks over 25 MHz).
169 */
m25p_probe(struct spi_mem * spimem)170 static int m25p_probe(struct spi_mem *spimem)
171 {
172 struct spi_device *spi = spimem->spi;
173 struct flash_platform_data *data;
174 struct m25p *flash;
175 struct spi_nor *nor;
176 struct spi_nor_hwcaps hwcaps = {
177 .mask = SNOR_HWCAPS_READ |
178 SNOR_HWCAPS_READ_FAST |
179 SNOR_HWCAPS_PP,
180 };
181 char *flash_name;
182 int ret;
183
184 data = dev_get_platdata(&spimem->spi->dev);
185
186 flash = devm_kzalloc(&spimem->spi->dev, sizeof(*flash), GFP_KERNEL);
187 if (!flash)
188 return -ENOMEM;
189
190 nor = &flash->spi_nor;
191
192 /* install the hooks */
193 nor->read = m25p80_read;
194 nor->write = m25p80_write;
195 nor->write_reg = m25p80_write_reg;
196 nor->read_reg = m25p80_read_reg;
197
198 nor->dev = &spimem->spi->dev;
199 spi_nor_set_flash_node(nor, spi->dev.of_node);
200 nor->priv = flash;
201
202 spi_mem_set_drvdata(spimem, flash);
203 flash->spimem = spimem;
204
205 if (spi->mode & SPI_RX_QUAD) {
206 hwcaps.mask |= SNOR_HWCAPS_READ_1_1_4;
207
208 if (spi->mode & SPI_TX_QUAD)
209 hwcaps.mask |= (SNOR_HWCAPS_READ_1_4_4 |
210 SNOR_HWCAPS_PP_1_1_4 |
211 SNOR_HWCAPS_PP_1_4_4);
212 } else if (spi->mode & SPI_RX_DUAL) {
213 hwcaps.mask |= SNOR_HWCAPS_READ_1_1_2;
214
215 if (spi->mode & SPI_TX_DUAL)
216 hwcaps.mask |= SNOR_HWCAPS_READ_1_2_2;
217 }
218
219 if (data && data->name)
220 nor->mtd.name = data->name;
221
222 if (!nor->mtd.name)
223 nor->mtd.name = spi_mem_get_name(spimem);
224
225 /* For some (historical?) reason many platforms provide two different
226 * names in flash_platform_data: "name" and "type". Quite often name is
227 * set to "m25p80" and then "type" provides a real chip name.
228 * If that's the case, respect "type" and ignore a "name".
229 */
230 if (data && data->type)
231 flash_name = data->type;
232 else if (!strcmp(spi->modalias, "spi-nor"))
233 flash_name = NULL; /* auto-detect */
234 else
235 flash_name = spi->modalias;
236
237 ret = spi_nor_scan(nor, flash_name, &hwcaps);
238 if (ret)
239 return ret;
240
241 return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
242 data ? data->nr_parts : 0);
243 }
244
245
m25p_remove(struct spi_mem * spimem)246 static int m25p_remove(struct spi_mem *spimem)
247 {
248 struct m25p *flash = spi_mem_get_drvdata(spimem);
249
250 spi_nor_restore(&flash->spi_nor);
251
252 /* Clean up MTD stuff. */
253 return mtd_device_unregister(&flash->spi_nor.mtd);
254 }
255
m25p_shutdown(struct spi_mem * spimem)256 static void m25p_shutdown(struct spi_mem *spimem)
257 {
258 struct m25p *flash = spi_mem_get_drvdata(spimem);
259
260 spi_nor_restore(&flash->spi_nor);
261 }
262 /*
263 * Do NOT add to this array without reading the following:
264 *
265 * Historically, many flash devices are bound to this driver by their name. But
266 * since most of these flash are compatible to some extent, and their
267 * differences can often be differentiated by the JEDEC read-ID command, we
268 * encourage new users to add support to the spi-nor library, and simply bind
269 * against a generic string here (e.g., "jedec,spi-nor").
270 *
271 * Many flash names are kept here in this list (as well as in spi-nor.c) to
272 * keep them available as module aliases for existing platforms.
273 */
274 static const struct spi_device_id m25p_ids[] = {
275 /*
276 * Allow non-DT platform devices to bind to the "spi-nor" modalias, and
277 * hack around the fact that the SPI core does not provide uevent
278 * matching for .of_match_table
279 */
280 {"spi-nor"},
281
282 /*
283 * Entries not used in DTs that should be safe to drop after replacing
284 * them with "spi-nor" in platform data.
285 */
286 {"s25sl064a"}, {"w25x16"}, {"m25p10"}, {"m25px64"},
287
288 /*
289 * Entries that were used in DTs without "jedec,spi-nor" fallback and
290 * should be kept for backward compatibility.
291 */
292 {"at25df321a"}, {"at25df641"}, {"at26df081a"},
293 {"mx25l4005a"}, {"mx25l1606e"}, {"mx25l6405d"}, {"mx25l12805d"},
294 {"mx25l25635e"},{"mx66l51235l"},
295 {"n25q064"}, {"n25q128a11"}, {"n25q128a13"}, {"n25q512a"},
296 {"s25fl256s1"}, {"s25fl512s"}, {"s25sl12801"}, {"s25fl008k"},
297 {"s25fl064k"},
298 {"sst25vf040b"},{"sst25vf016b"},{"sst25vf032b"},{"sst25wf040"},
299 {"m25p40"}, {"m25p80"}, {"m25p16"}, {"m25p32"},
300 {"m25p64"}, {"m25p128"},
301 {"w25x80"}, {"w25x32"}, {"w25q32"}, {"w25q32dw"},
302 {"w25q80bl"}, {"w25q128"}, {"w25q256"},
303
304 /* Flashes that can't be detected using JEDEC */
305 {"m25p05-nonjedec"}, {"m25p10-nonjedec"}, {"m25p20-nonjedec"},
306 {"m25p40-nonjedec"}, {"m25p80-nonjedec"}, {"m25p16-nonjedec"},
307 {"m25p32-nonjedec"}, {"m25p64-nonjedec"}, {"m25p128-nonjedec"},
308
309 /* Everspin MRAMs (non-JEDEC) */
310 { "mr25h128" }, /* 128 Kib, 40 MHz */
311 { "mr25h256" }, /* 256 Kib, 40 MHz */
312 { "mr25h10" }, /* 1 Mib, 40 MHz */
313 { "mr25h40" }, /* 4 Mib, 40 MHz */
314
315 { },
316 };
317 MODULE_DEVICE_TABLE(spi, m25p_ids);
318
319 static const struct of_device_id m25p_of_table[] = {
320 /*
321 * Generic compatibility for SPI NOR that can be identified by the
322 * JEDEC READ ID opcode (0x9F). Use this, if possible.
323 */
324 { .compatible = "jedec,spi-nor" },
325 {}
326 };
327 MODULE_DEVICE_TABLE(of, m25p_of_table);
328
329 static struct spi_mem_driver m25p80_driver = {
330 .spidrv = {
331 .driver = {
332 .name = "m25p80",
333 .of_match_table = m25p_of_table,
334 },
335 .id_table = m25p_ids,
336 },
337 .probe = m25p_probe,
338 .remove = m25p_remove,
339 .shutdown = m25p_shutdown,
340
341 /* REVISIT: many of these chips have deep power-down modes, which
342 * should clearly be entered on suspend() to minimize power use.
343 * And also when they're otherwise idle...
344 */
345 };
346
347 module_spi_mem_driver(m25p80_driver);
348
349 MODULE_LICENSE("GPL");
350 MODULE_AUTHOR("Mike Lavender");
351 MODULE_DESCRIPTION("MTD SPI driver for ST M25Pxx flash chips");
352
