[U-Boot] [U-Boot,v2 6/6] sf: Set QUAD enable bit support

[Jagan Teki]

Tested on real hardware, works fine.

Tested-by: Jagannadha Sutradharudu Teki <jagannadh.teki at gmail.com>

Thanks,
Jagan.

On Wed, Dec 19, 2012 at 9:57 PM, Jagannadha Sutradharudu Teki
<jagannadh.teki at gmail.com> wrote:
> This patch provides support to set the QUAD enable bit on flash.
>
> QUAD enable bit needs to set before performing any QUAD IO operations
> on respective SPI flashes.
>
> User need to use spi_flash_set_quad_enable_bit() to set the
> QUAD enable bit based on their usage.
>
> Signed-off-by: Jagannadha Sutradharudu Teki <jagannadh.teki at gmail.com>
> ---
> Changes in v2:
>         Improved code logic
>
>  drivers/mtd/spi/spi_flash.c          |   31 +++++++++++++++++++++++++++++++
>  drivers/mtd/spi/spi_flash_internal.h |    4 ++++
>  2 files changed, 35 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
> index 5bddde4..675a0bf 100644
> --- a/drivers/mtd/spi/spi_flash.c
> +++ b/drivers/mtd/spi/spi_flash.c
> @@ -329,6 +329,37 @@ int spi_flash_cmd_read_config(struct spi_flash *flash, void *data)
>         return 0;
>  }
>
> +int spi_flash_set_quad_enable_bit(struct spi_flash *flash)
> +{
> +       u8 data = 0, write_done = 0;
> +       int ret, pass;
> +
> +       for (pass = 0; pass < 2; pass++) {
> +               ret = spi_flash_cmd_read_config(flash, (void *)&data);
> +               if (ret < 0) {
> +                       debug("SF: fail to read config register\n");
> +                       return ret;
> +               }
> +
> +               if (data & STATUS_QEB) {
> +                       debug("SF: quad enable bit is set.\n");
> +                       return ret;
> +               } else if (write_done != 1) {
> +                       debug("SF: need to set quad enable bit\n");
> +
> +                       write_done = 1;
> +                       ret = spi_flash_cmd_write_config(flash, STATUS_QEB);
> +                       if (ret < 0) {
> +                               debug("SF: fail to write quad enable bit\n");
> +                               return ret;
> +                       }
> +               }
> +       }
> +
> +       debug("SF: fail to set quad enable bit\n");
> +       return -1;
> +}
> +
>  /*
>   * The following table holds all device probe functions
>   *
> diff --git a/drivers/mtd/spi/spi_flash_internal.h b/drivers/mtd/spi/spi_flash_internal.h
> index 844e82e..15c7ac4 100644
> --- a/drivers/mtd/spi/spi_flash_internal.h
> +++ b/drivers/mtd/spi/spi_flash_internal.h
> @@ -31,6 +31,7 @@
>
>  /* Common status */
>  #define STATUS_WIP                     0x01
> +#define STATUS_QEB                     0x02
>
>  /* Send a single-byte command to the device and read the response */
>  int spi_flash_cmd(struct spi_slave *spi, u8 cmd, void *response, size_t len);
> @@ -87,6 +88,9 @@ int spi_flash_cmd_write_config(struct spi_flash *flash, u8 cr);
>  /* Read the config register */
>  int spi_flash_cmd_read_config(struct spi_flash *flash, void *data);
>
> +/* Set the QUAD enable bit */
> +int spi_flash_set_quad_enable_bit(struct spi_flash *flash);
> +
>  /*
>   * Same as spi_flash_cmd_read() except it also claims/releases the SPI
>   * bus. Used as common part of the ->read() operation.
> --
> 1.7.0.4
>