diff options
| author | Sai Krishna Potthuri <sai.krishna.potthuri@amd.com> | 2022-09-08 12:14:28 +0530 |
|---|---|---|
| committer | Tudor Ambarus <tudor.ambarus@microchip.com> | 2022-10-25 05:11:34 +0300 |
| commit | 8f1ee9ef71d0c0b185d2afc800e68d6addf29fe5 (patch) | |
| tree | d13410de757c1b5e663ccbe675528e8c049c2d83 /drivers/mtd | |
| parent | 7f2937efe18630832c8eae7a74e8c19fc1e7936e (diff) | |
mtd: spi-nor: Add support for flash reset
Add support for spi-nor flash reset via GPIO controller by reading the
reset-gpio property. If there is a valid GPIO specifier then reset will
be performed by asserting and deasserting the GPIO using gpiod APIs
otherwise it will not perform any operation.
Signed-off-by: Sai Krishna Potthuri <sai.krishna.potthuri@amd.com>
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Reviewed-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220908064428.2962-3-sai.krishna.potthuri@amd.com
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/spi-nor/core.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index f2c64006f8d7..a78ab9bae2be 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -2933,6 +2933,27 @@ static void spi_nor_set_mtd_info(struct spi_nor *nor) mtd->_put_device = spi_nor_put_device; } +static int spi_nor_hw_reset(struct spi_nor *nor) +{ + struct gpio_desc *reset; + + reset = devm_gpiod_get_optional(nor->dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR_OR_NULL(reset)) + return PTR_ERR_OR_ZERO(reset); + + /* + * Experimental delay values by looking at different flash device + * vendors datasheets. + */ + usleep_range(1, 5); + gpiod_set_value_cansleep(reset, 1); + usleep_range(100, 150); + gpiod_set_value_cansleep(reset, 0); + usleep_range(1000, 1200); + + return 0; +} + int spi_nor_scan(struct spi_nor *nor, const char *name, const struct spi_nor_hwcaps *hwcaps) { @@ -2965,6 +2986,10 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, if (!nor->bouncebuf) return -ENOMEM; + ret = spi_nor_hw_reset(nor); + if (ret) + return ret; + info = spi_nor_get_flash_info(nor, name); if (IS_ERR(info)) return PTR_ERR(info); |