Hi Sunny,

On 13/12/2018 09:39, Sunny Luo wrote:
> The SPICC controller in Meson-AXG is capable of driving the CLK/MOSI/SS
> signal lines through the idle state (between two transmission operation),
> which avoid the signals floating in unexpected state.

This is welcome, because it's really missing on GX...
I tried implementing it with pinctrl at [1], but it's complex.

Can you provide more info on how we should implement in on GX to be on par ?

[1] 
https://github.com/superna9999/linux/commit/9c3a95659dd532d186556c1570c54d79ea5a4d45

> 
> Signed-off-by: Sunny Luo <sunny....@amlogic.com>
> Signed-off-by: Yixun Lan <yixun....@amlogic.com>
> ---
>  drivers/spi/spi-meson-spicc.c | 28 ++++++++++++++++++++++++++--
>  1 file changed, 26 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/spi/spi-meson-spicc.c b/drivers/spi/spi-meson-spicc.c
> index b56249d..0384c28 100644
> --- a/drivers/spi/spi-meson-spicc.c
> +++ b/drivers/spi/spi-meson-spicc.c
> @@ -115,6 +115,13 @@
>  
>  #define SPICC_DWADDR 0x24    /* Write Address of DMA */
>  
> +#define SPICC_ENH_CTL0       0x38    /* Enhanced Feature */
> +#define SPICC_ENH_MOSI_OEN           BIT(25)
> +#define SPICC_ENH_CLK_OEN            BIT(26)
> +#define SPICC_ENH_CS_OEN             BIT(27)
> +#define SPICC_ENH_CLK_CS_DELAY_EN    BIT(28)
> +#define SPICC_ENH_MAIN_CLK_AO                BIT(29)
> +
>  #define writel_bits_relaxed(mask, val, addr) \
>       writel_relaxed((readl_relaxed(addr) & ~(mask)) | (val), addr)
>  
> @@ -123,6 +130,7 @@
>  
>  struct meson_spicc_data {
>       unsigned int                    max_speed_hz;
> +     bool                            has_oen;
>  };
>  
>  struct meson_spicc_device {
> @@ -145,6 +153,19 @@ struct meson_spicc_device {
>       bool                            is_last_burst;
>  };
>  
> +static void meson_spicc_oen_enable(struct meson_spicc_device *spicc)
> +{
> +     u32 conf;
> +
> +     if (!spicc->data->has_oen)
> +             return;
> +
> +     conf = readl_relaxed(spicc->base + SPICC_ENH_CTL0) |
> +             SPICC_ENH_MOSI_OEN | SPICC_ENH_CLK_OEN | SPICC_ENH_CS_OEN;
> +
> +     writel_relaxed(conf, spicc->base + SPICC_ENH_CTL0);
> +}
> +
>  static inline bool meson_spicc_txfull(struct meson_spicc_device *spicc)
>  {
>       return !!FIELD_GET(SPICC_TF,
> @@ -453,6 +474,8 @@ static int meson_spicc_prepare_message(struct spi_master 
> *master,
>  
>       writel_bits_relaxed(BIT(24), BIT(24), spicc->base + SPICC_TESTREG);
>  
> +     meson_spicc_oen_enable(spicc);
> +
>       return 0;
>  }
>  
> @@ -610,11 +633,12 @@ static int meson_spicc_remove(struct platform_device 
> *pdev)
>  }
>  
>  static const struct meson_spicc_data meson_spicc_gx_data = {
> -     .max_speed_hz   = 30000000,
> +     .max_speed_hz           = 30000000,

Nitpick, but I would have kept the indentation here ...

>  };
>  
>  static const struct meson_spicc_data meson_spicc_axg_data = {
> -     .max_speed_hz   = 80000000,
> +     .max_speed_hz           = 80000000,
> +     .has_oen                = true,

same here

>  };
>  
>  static const struct of_device_id meson_spicc_of_match[] = {
> 

Anywy it's nitpick,

Reviewed-by: Neil Armstrong <narmstr...@baylibre.com>

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