@@ -3,7 +3,7 @@
Required properties:
- #address-cells, #size-cells : Must be present if the device has sub-nodes
representing partitions.
-- compatible : Must be "microchip,mchp23k256"
+- compatible : Must be one of "microchip,mchp23k256" or "microchip,mchp23lcv1024"
- reg : Chip-Select number
- spi-max-frequency : Maximum frequency of the SPI bus the chip can operate at
@@ -21,10 +21,14 @@
#include <linux/spi/spi.h>
#include <linux/of_device.h>
+#define MAX_CMD_SIZE 4
+enum chips { mchp23k256, mchp23lcv1024 };
+
struct mchp23k256_flash {
struct spi_device *spi;
struct mutex lock;
struct mtd_info mtd;
+ u8 addr_width;
};
#define MCHP23K256_CMD_WRITE_STATUS 0x01
@@ -34,22 +38,35 @@ struct mchp23k256_flash {
#define to_mchp23k256_flash(x) container_of(x, struct mchp23k256_flash, mtd)
+static void mchp23k256_addr2cmd(struct mchp23k256_flash *flash,
+ unsigned int addr, u8 *cmd)
+{
+ /* cmd[0] has opcode */
+ cmd[1] = addr >> (flash->addr_width * 8 - 8);
+ cmd[2] = addr >> (flash->addr_width * 8 - 16);
+ cmd[3] = addr >> (flash->addr_width * 8 - 24);
+}
+
+static int mchp23k256_cmdsz(struct mchp23k256_flash *flash)
+{
+ return 1 + flash->addr_width;
+}
+
static int mchp23k256_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const unsigned char *buf)
{
struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd);
struct spi_transfer transfer[2] = {};
struct spi_message message;
- unsigned char command[3];
+ unsigned char command[MAX_CMD_SIZE];
spi_message_init(&message);
command[0] = MCHP23K256_CMD_WRITE;
- command[1] = to >> 8;
- command[2] = to;
+ mchp23k256_addr2cmd(flash, to, command);
transfer[0].tx_buf = command;
- transfer[0].len = sizeof(command);
+ transfer[0].len = mchp23k256_cmdsz(flash);
spi_message_add_tail(&transfer[0], &message);
transfer[1].tx_buf = buf;
@@ -73,17 +90,16 @@ static int mchp23k256_read(struct mtd_info *mtd, loff_t from, size_t len,
struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd);
struct spi_transfer transfer[2] = {};
struct spi_message message;
- unsigned char command[3];
+ unsigned char command[MAX_CMD_SIZE];
spi_message_init(&message);
memset(&transfer, 0, sizeof(transfer));
command[0] = MCHP23K256_CMD_READ;
- command[1] = from >> 8;
- command[2] = from;
+ mchp23k256_addr2cmd(flash, from, command);
transfer[0].tx_buf = command;
- transfer[0].len = sizeof(command);
+ transfer[0].len = mchp23k256_cmdsz(flash);
spi_message_add_tail(&transfer[0], &message);
transfer[1].rx_buf = buf;
@@ -128,6 +144,7 @@ static int mchp23k256_probe(struct spi_device *spi)
struct mchp23k256_flash *flash;
struct flash_platform_data *data;
int err;
+ enum chips chip;
flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL);
if (!flash)
@@ -143,15 +160,30 @@ static int mchp23k256_probe(struct spi_device *spi)
data = dev_get_platdata(&spi->dev);
+ if (spi->dev.of_node)
+ chip = (enum chips)of_device_get_match_data(&spi->dev);
+ else
+ chip = mchp23k256;
+
mtd_set_of_node(&flash->mtd, spi->dev.of_node);
flash->mtd.dev.parent = &spi->dev;
flash->mtd.type = MTD_RAM;
flash->mtd.flags = MTD_CAP_RAM;
flash->mtd.writesize = 1;
- flash->mtd.size = SZ_32K;
flash->mtd._read = mchp23k256_read;
flash->mtd._write = mchp23k256_write;
+ switch (chip) {
+ case mchp23lcv1024:
+ flash->mtd.size = SZ_128K;
+ flash->addr_width = 3;
+ break;
+ default:
+ flash->mtd.size = SZ_32K;
+ flash->addr_width = 2;
+ break;
+ }
+
flash->mtd.erasesize = PAGE_SIZE;
while (flash->mtd.size & (flash->mtd.erasesize - 1))
flash->mtd.erasesize >>= 1;
@@ -172,7 +204,8 @@ static int mchp23k256_remove(struct spi_device *spi)
}
static const struct of_device_id mchp23k256_of_table[] = {
- { .compatible = "microchip,mchp23k256" },
+ { .compatible = "microchip,mchp23k256", .data = (void *)mchp23k256 },
+ { .compatible = "microchip,mchp23lcv1024", .data = (void *)mchp23lcv1024 },
{}
};
MODULE_DEVICE_TABLE(of, mchp23k256_of_table);
The mchp23lcv1024 is software compatible with the mchp23k256, the only difference (from a software point of view) is the size. There is no way to detect the size so we must be told via a Device Tree. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> --- Changes in v2: - fix formatting in switch statement - add support for 24-bit addressing .../bindings/mtd/microchip,mchp23k256.txt | 2 +- drivers/mtd/devices/mchp23k256.c | 53 ++++++++++++++++++---- 2 files changed, 44 insertions(+), 11 deletions(-)