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