Re: [PATCH 2/3] spi: sun6i: Support Allwinner H3 SPI controller

[Chen-Yu Tsai]

On Wed, Oct 19, 2016 at 10:02 PM, Milo Kim <woogyom.kim@xxxxxxxxx> wrote:
> H3 has two SPI controllers. The size of the buffer is 64 * 8.
> (8 bit transfer by 64 entry FIFO)
> A31 has four controllers. The size of the buffer is 128 * 8.
> (8 bit transfer by 128 entry FIFO)
>
> Register maps are sharable, so sun6i SPI driver is reusable with
> device configuration.
>
> Use the variable, 'fifo_depth' instead of fixed value to support both SPI
> controllers.
>
> Cc: Mark Brown <broonie@xxxxxxxxxx>
> Cc: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
> Cc: Chen-Yu Tsai <wens@xxxxxxxx>
> Signed-off-by: Milo Kim <woogyom.kim@xxxxxxxxx>
> ---
>  drivers/spi/Kconfig     |  4 ++--
>  drivers/spi/spi-sun6i.c | 38 +++++++++++++++++++++++++++-----------
>  2 files changed, 29 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index b799547..06d0845 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -610,11 +610,11 @@ config SPI_SUN4I
>           SPI driver for Allwinner sun4i, sun5i and sun7i SoCs
>
>  config SPI_SUN6I
> -       tristate "Allwinner A31 SPI controller"
> +       tristate "Allwinner A31/H3 SPI controller"
>         depends on ARCH_SUNXI || COMPILE_TEST
>         depends on RESET_CONTROLLER
>         help
> -         This enables using the SPI controller on the Allwinner A31 SoCs.
> +         This enables using the SPI controller on the Allwinner A31/H3 SoCs.
>
>  config SPI_MXS
>         tristate "Freescale MXS SPI controller"
> diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
> index 9918a57..91235b2 100644
> --- a/drivers/spi/spi-sun6i.c
> +++ b/drivers/spi/spi-sun6i.c
> @@ -17,6 +17,7 @@
>  #include <linux/interrupt.h>
>  #include <linux/io.h>
>  #include <linux/module.h>
> +#include <linux/of_device.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
>  #include <linux/reset.h>
> @@ -24,6 +25,7 @@
>  #include <linux/spi/spi.h>
>
>  #define SUN6I_FIFO_DEPTH               128
> +#define SUN8I_FIFO_DEPTH               64
>
>  #define SUN6I_GBL_CTL_REG              0x04
>  #define SUN6I_GBL_CTL_BUS_ENABLE               BIT(0)
> @@ -90,6 +92,7 @@ struct sun6i_spi {
>         const u8                *tx_buf;
>         u8                      *rx_buf;
>         int                     len;
> +       int                     fifo_depth;
>  };
>
>  static inline u32 sun6i_spi_read(struct sun6i_spi *sspi, u32 reg)
> @@ -155,7 +158,9 @@ static void sun6i_spi_set_cs(struct spi_device *spi, bool enable)
>
>  static size_t sun6i_spi_max_transfer_size(struct spi_device *spi)
>  {
> -       return SUN6I_FIFO_DEPTH - 1;
> +       struct sun6i_spi *sspi = spi_master_get_devdata(spi->master);
> +
> +       return sspi->fifo_depth - 1;
>  }
>
>  static int sun6i_spi_transfer_one(struct spi_master *master,
> @@ -170,7 +175,7 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
>         u32 reg;
>
>         /* We don't support transfer larger than the FIFO */
> -       if (tfr->len > SUN6I_FIFO_DEPTH)
> +       if (tfr->len > sspi->fifo_depth)
>                 return -EINVAL;
>
>         reinit_completion(&sspi->done);
> @@ -265,7 +270,7 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
>                         SUN6I_BURST_CTL_CNT_STC(tx_len));
>
>         /* Fill the TX FIFO */
> -       sun6i_spi_fill_fifo(sspi, SUN6I_FIFO_DEPTH);
> +       sun6i_spi_fill_fifo(sspi, sspi->fifo_depth);
>
>         /* Enable the interrupts */
>         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, SUN6I_INT_CTL_TC);
> @@ -288,7 +293,7 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
>                 goto out;
>         }
>
> -       sun6i_spi_drain_fifo(sspi, SUN6I_FIFO_DEPTH);
> +       sun6i_spi_drain_fifo(sspi, sspi->fifo_depth);
>
>  out:
>         sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, 0);
> @@ -360,8 +365,16 @@ static int sun6i_spi_runtime_suspend(struct device *dev)
>         return 0;
>  }
>
> +static const struct of_device_id sun6i_spi_match[] = {
> +       { .compatible = "allwinner,sun6i-a31-spi", .data = (int *)SUN6I_FIFO_DEPTH },
> +       { .compatible = "allwinner,sun8i-h3-spi", .data = (int *)SUN8I_FIFO_DEPTH },
> +       {}
> +};
> +MODULE_DEVICE_TABLE(of, sun6i_spi_match);
> +
>  static int sun6i_spi_probe(struct platform_device *pdev)
>  {
> +       const struct of_device_id *id;
>         struct spi_master *master;
>         struct sun6i_spi *sspi;
>         struct resource *res;
> @@ -398,6 +411,15 @@ static int sun6i_spi_probe(struct platform_device *pdev)
>         }
>
>         sspi->master = master;
> +
> +       id = of_match_device(sun6i_spi_match, &pdev->dev);

Use of_device_get_match_data, then you don't even have to move sun6i_spi_match
above this function.

ChenYu

> +       if (!id) {
> +               dev_err(&pdev->dev, "Cannot get device ID\n");
> +               goto err_free_master;
> +       }
> +
> +       sspi->fifo_depth = (int)id->data;
> +
>         master->max_speed_hz = 100 * 1000 * 1000;
>         master->min_speed_hz = 3 * 1000;
>         master->set_cs = sun6i_spi_set_cs;
> @@ -469,12 +491,6 @@ static int sun6i_spi_remove(struct platform_device *pdev)
>         return 0;
>  }
>
> -static const struct of_device_id sun6i_spi_match[] = {
> -       { .compatible = "allwinner,sun6i-a31-spi", },
> -       {}
> -};
> -MODULE_DEVICE_TABLE(of, sun6i_spi_match);
> -
>  static const struct dev_pm_ops sun6i_spi_pm_ops = {
>         .runtime_resume         = sun6i_spi_runtime_resume,
>         .runtime_suspend        = sun6i_spi_runtime_suspend,
> @@ -493,5 +509,5 @@ module_platform_driver(sun6i_spi_driver);
>
>  MODULE_AUTHOR("Pan Nan <pannan@xxxxxxxxxxxxxxxxx>");
>  MODULE_AUTHOR("Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>");
> -MODULE_DESCRIPTION("Allwinner A31 SPI controller driver");
> +MODULE_DESCRIPTION("Allwinner A31/H3 SPI controller driver");
>  MODULE_LICENSE("GPL");
> --
> 2.9.3
>