drivers/mtd/devices/m25p80.c

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