target/linux/bcm53xx/files/drivers/mtd/spi-nor/bcm53xxspiflash.c

   1 #include <linux/module.h>
   2 #include <linux/delay.h>
   3 #include <linux/spi/spi.h>
   4 #include <linux/mtd/spi-nor.h>
   5 #include <linux/mtd/mtd.h>
   6 #include <linux/mtd/cfi.h>
   7
   8 static const char * const probes[] = { "bcm47xxpart", NULL };
   9
  10 struct bcm53xxsf {
  11         struct spi_device *spi;
  12         struct mtd_info mtd;
  13         struct spi_nor nor;
  14 };
  15
  16 /**************************************************
  17  * spi-nor API
  18  **************************************************/
  19
  20 static int bcm53xxspiflash_read_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
  21                                    int len)
  22 {
  23         struct bcm53xxsf *b53sf = nor->priv;
  24
  25         return spi_write_then_read(b53sf->spi, &opcode, 1, buf, len);
  26 }
  27
  28 static int bcm53xxspiflash_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf,
  29                                      int len, int write_enable)
  30 {
  31         struct bcm53xxsf *b53sf = nor->priv;
  32         u8 *cmd = kzalloc(len + 1, GFP_KERNEL);
  33         int err;
  34
  35         if (!cmd)
  36                 return -ENOMEM;
  37
  38         cmd[0] = opcode;
  39         memcpy(&cmd[1], buf, len);
  40         err = spi_write(b53sf->spi, cmd, len + 1);
  41
  42         kfree(cmd);
  43
  44         return err;
  45 }
  46
  47 static int bcm53xxspiflash_read(struct spi_nor *nor, loff_t from, size_t len,
  48                                 size_t *retlen, u_char *buf)
  49 {
  50         struct bcm53xxsf *b53sf = nor->priv;
  51         struct spi_message m;
  52         struct spi_transfer t[2] = { { 0 }, { 0 } };
  53         unsigned char cmd[5];
  54         int cmd_len = 0;
  55         int err;
  56
  57         spi_message_init(&m);
  58
  59         cmd[cmd_len++] = SPINOR_OP_READ;
  60         if (b53sf->mtd.size > 0x1000000)
  61                 cmd[cmd_len++] = (from & 0xFF000000) >> 24;
  62         cmd[cmd_len++] = (from & 0x00FF0000) >> 16;
  63         cmd[cmd_len++] = (from & 0x0000FF00) >> 8;
  64         cmd[cmd_len++] = (from & 0x000000FF) >> 0;
  65
  66         t[0].tx_buf = cmd;
  67         t[0].len = cmd_len;
  68         spi_message_add_tail(&t[0], &m);
  69
  70         t[1].rx_buf = buf;
  71         t[1].len = len;
  72         spi_message_add_tail(&t[1], &m);
  73
  74         err = spi_sync(b53sf->spi, &m);
  75         if (err)
  76                 return err;
  77
  78         if (retlen && m.actual_length > cmd_len)
  79                 *retlen = m.actual_length - cmd_len;
  80
  81         return 0;
  82 }
  83
  84 static void bcm53xxspiflash_write(struct spi_nor *nor, loff_t to, size_t len,
  85                                   size_t *retlen, const u_char *buf)
  86 {
  87         struct bcm53xxsf *b53sf = nor->priv;
  88         struct spi_message m;
  89         struct spi_transfer t = { 0 };
  90         u8 *cmd = kzalloc(len + 5, GFP_KERNEL);
  91         int cmd_len = 0;
  92         int err;
  93
  94         if (!cmd)
  95                 return;
  96
  97         spi_message_init(&m);
  98
  99         cmd[cmd_len++] = nor->program_opcode;
 100         if (b53sf->mtd.size > 0x1000000)
 101                 cmd[cmd_len++] = (to & 0xFF000000) >> 24;
 102         cmd[cmd_len++] = (to & 0x00FF0000) >> 16;
 103         cmd[cmd_len++] = (to & 0x0000FF00) >> 8;
 104         cmd[cmd_len++] = (to & 0x000000FF) >> 0;
 105         memcpy(&cmd[cmd_len], buf, len);
 106
 107         t.tx_buf = cmd;
 108         t.len = cmd_len + len;
 109         spi_message_add_tail(&t, &m);
 110
 111         err = spi_sync(b53sf->spi, &m);
 112         if (err)
 113                 goto out;
 114
 115         if (retlen && m.actual_length > cmd_len)
 116                 *retlen += m.actual_length - cmd_len;
 117
 118 out:
 119         kfree(cmd);
 120 }
 121
 122 static int bcm53xxspiflash_erase(struct spi_nor *nor, loff_t offs)
 123 {
 124         struct bcm53xxsf *b53sf = nor->priv;
 125         unsigned char cmd[5];
 126         int i;
 127
 128         i = 0;
 129         cmd[i++] = nor->erase_opcode;
 130         if (b53sf->mtd.size > 0x1000000)
 131                 cmd[i++] = (offs & 0xFF000000) >> 24;
 132         cmd[i++] = ((offs & 0x00FF0000) >> 16);
 133         cmd[i++] = ((offs & 0x0000FF00) >> 8);
 134         cmd[i++] = ((offs & 0x000000FF) >> 0);
 135
 136         return spi_write(b53sf->spi, cmd, i);
 137 }
 138
 139 static const char *bcm53xxspiflash_chip_name(struct spi_nor *nor)
 140 {
 141         struct bcm53xxsf *b53sf = nor->priv;
 142         struct device *dev = &b53sf->spi->dev;
 143         unsigned char cmd[4];
 144         unsigned char resp[2];
 145         int err;
 146
 147         /* SST and Winbond/NexFlash specific command */
 148         cmd[0] = 0x90; /* Read Manufacturer / Device ID */
 149         cmd[1] = 0;
 150         cmd[2] = 0;
 151         cmd[3] = 0;
 152         err = spi_write_then_read(b53sf->spi, cmd, 4, resp, 2);
 153         if (err < 0) {
 154                 dev_err(dev, "error reading SPI flash id\n");
 155                 return ERR_PTR(-EBUSY);
 156         }
 157         switch (resp[0]) {
 158         case 0xef: /* Winbond/NexFlash */
 159                 switch (resp[1]) {
 160                 case 0x17:
 161                         return "w25q128";
 162                 }
 163                 dev_err(dev, "Unknown Winbond/NexFlash flash: %02X %02X\n",
 164                         resp[0], resp[1]);
 165                 return NULL;
 166         }
 167
 168         /* TODO: Try more ID commands */
 169
 170         return NULL;
 171 }
 172
 173 /**************************************************
 174  * SPI driver
 175  **************************************************/
 176
 177 static int bcm53xxspiflash_probe(struct spi_device *spi)
 178 {
 179         struct bcm53xxsf *b53sf;
 180         struct spi_nor *nor;
 181         int err;
 182
 183         b53sf = devm_kzalloc(&spi->dev, sizeof(*b53sf), GFP_KERNEL);
 184         if (!b53sf)
 185                 return -ENOMEM;
 186         spi_set_drvdata(spi, b53sf);
 187
 188         nor = &b53sf->nor;
 189         b53sf->spi = spi;
 190         b53sf->mtd.priv = &b53sf->nor;
 191
 192         nor->mtd = &b53sf->mtd;
 193         nor->dev = &spi->dev;
 194         nor->read_reg = bcm53xxspiflash_read_reg;
 195         nor->write_reg = bcm53xxspiflash_write_reg;
 196         nor->read = bcm53xxspiflash_read;
 197         nor->write = bcm53xxspiflash_write;
 198         nor->erase = bcm53xxspiflash_erase;
 199         nor->priv = b53sf;
 200
 201         err = spi_nor_scan(&b53sf->nor, bcm53xxspiflash_chip_name(nor),
 202                            SPI_NOR_NORMAL);
 203         if (err)
 204                 return err;
 205
 206         err = mtd_device_parse_register(&b53sf->mtd, probes, NULL, NULL, 0);
 207         if (err)
 208                 return err;
 209
 210         return 0;
 211 }
 212
 213 static int bcm53xxspiflash_remove(struct spi_device *spi)
 214 {
 215         return 0;
 216 }
 217
 218 static struct spi_driver bcm53xxspiflash_driver = {
 219         .driver = {
 220                 .name   = "bcm53xxspiflash",
 221                 .owner  = THIS_MODULE,
 222         },
 223         .probe          = bcm53xxspiflash_probe,
 224         .remove         = bcm53xxspiflash_remove,
 225 };
 226
 227 module_spi_driver(bcm53xxspiflash_driver);