On Wed, Feb 19, 2020 at 08:08:58PM +0200, Andrey Lebedev wrote:
> From: Andrey Lebedev <andrey@lebedev.lt>
>
> A20 SoC (found in Cubieboard 2 among others) requires different LVDS set
> up procedure than A33. Timing controller (tcon) driver only implements
> sun6i-style procedure, that doesn't work on A20 (sun7i).
>
> Signed-off-by: Andrey Lebedev <andrey@lebedev.lt>
> ---
>  drivers/gpu/drm/sun4i/sun4i_tcon.c | 37 +++++++++++++++++++++++++++++-
>  drivers/gpu/drm/sun4i/sun4i_tcon.h | 11 +++++++++
>  2 files changed, 47 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> index b7234eef3c7b..09ee6e8c6914 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> @@ -114,6 +114,30 @@ static void sun4i_tcon_channel_set_status(struct sun4i_tcon *tcon, int channel,
>  	}
>  }
>
> +static void sun4i_tcon_setup_lvds_phy(struct sun4i_tcon *tcon,
> +				      const struct drm_encoder *encoder)
> +{
> +	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
> +		     SUN4I_TCON0_LVDS_ANA0_CK_EN |
> +		     SUN4I_TCON0_LVDS_ANA0_REG_V |
> +		     SUN4I_TCON0_LVDS_ANA0_REG_C |
> +		     SUN4I_TCON0_LVDS_ANA0_EN_MB |
> +		     SUN4I_TCON0_LVDS_ANA0_PD |
> +		     SUN4I_TCON0_LVDS_ANA0_DCHS);
> +
> +	udelay(2); /* delay at least 1200 ns */
> +	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA1_REG,
> +			   SUN4I_TCON0_LVDS_ANA1_INIT,
> +			   SUN4I_TCON0_LVDS_ANA1_INIT);
> +	udelay(1); /* delay at least 120 ns */
> +	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA1_REG,
> +			   SUN4I_TCON0_LVDS_ANA1_UPDATE,
> +			   SUN4I_TCON0_LVDS_ANA1_UPDATE);
> +	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
> +			   SUN4I_TCON0_LVDS_ANA0_EN_MB,
> +			   SUN4I_TCON0_LVDS_ANA0_EN_MB);
> +}
> +
>  static void sun6i_tcon_setup_lvds_phy(struct sun4i_tcon *tcon,
>  				      const struct drm_encoder *encoder)
>  {
> @@ -1455,7 +1479,18 @@ static const struct sun4i_tcon_quirks sun6i_a31s_quirks = {
>  	.dclk_min_div		= 1,
>  };
>
> +static const struct sun4i_tcon_quirks sun7i_a20_tcon0_quirks = {
> +	.supports_lvds		= true,
> +	.has_channel_0		= true,
> +	.has_channel_1		= true,
> +	.dclk_min_div		= 4,
> +	/* Same display pipeline structure as A10 */
> +	.set_mux		= sun4i_a10_tcon_set_mux,
> +	.setup_lvds_phy		= sun4i_tcon_setup_lvds_phy,
> +};
> +
>  static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
> +	.supports_lvds		= false,

False is already the default here.

I've removed it while applying

Maxime