Add support for spi-nor flash reset via GPIO controller by reading the reset-gpios property.
Signed-off-by: Venkatesh Yadav Abbarapu <[email protected]> Signed-off-by: Padmarao Begari <[email protected]> --- drivers/mtd/spi/spi-nor-core.c | 40 ++++++++++++++++++++++++++++++++++ include/linux/mtd/spi-nor.h | 1 + 2 files changed, 41 insertions(+) diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index 76c33b24368..0c132a39190 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -4466,6 +4466,40 @@ void spi_nor_set_fixups(struct spi_nor *nor) #endif /* SPI_FLASH_MACRONIX */ } +static int spi_nor_hw_reset(struct spi_nor *nor) +{ +#if CONFIG_IS_ENABLED(DM_GPIO) + struct udevice *dev = nor->spi->dev; + int rc; + + nor->flash_gpio_reset = devm_gpiod_get_optional(dev, "reset", + GPIOD_IS_OUT | + GPIOD_ACTIVE_LOW); + + if (nor->flash_gpio_reset) { + /* + * Experimental delay values by looking at different flash device + * vendors datasheets. + */ + udelay(5); + + /* Toggle gpio to reset the flash device. */ + rc = dm_gpio_set_value(nor->flash_gpio_reset, 1); + if (rc) + return rc; + + udelay(150); + + rc = dm_gpio_set_value(nor->flash_gpio_reset, 0); + if (rc) + return rc; + + udelay(1200); + } +#endif + return 0; +} + int spi_nor_scan(struct spi_nor *nor) { struct spi_nor_flash_parameter params; @@ -4491,6 +4525,12 @@ int spi_nor_scan(struct spi_nor *nor) nor->setup = spi_nor_default_setup; + if (CONFIG_IS_ENABLED(DM_GPIO)) { + ret = spi_nor_hw_reset(nor); + if (ret) + return ret; + } + #ifdef CONFIG_SPI_FLASH_SOFT_RESET_ON_BOOT /* * When the flash is handed to us in a stateful mode like 8D-8D-8D, it diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index 4eef4ab0488..8017d0dd9db 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -583,6 +583,7 @@ struct spi_nor { u8 cmd_buf[SPI_NOR_MAX_CMD_SIZE]; enum spi_nor_cmd_ext cmd_ext_type; struct spi_nor_fixups *fixups; + struct gpio_desc *flash_gpio_reset; int (*setup)(struct spi_nor *nor, const struct flash_info *info, const struct spi_nor_flash_parameter *params); -- 2.34.1
