[PATCH] drm/omap: add OMAP5 DSIPHY lane-enable support

[Laurent Pinchart]

Hi Tomi,

Thank you for the patch.

On Thursday 10 Aug 2017 09:45:20 Tomi Valkeinen wrote:
> We are missing OMAP5 DSIPHY lane-enable support, which has prevented
> OMAP5 DSI working in mainline. This patch adds the lane-enable similarly
> to the recently added OMAP4 version.
> 
> Signed-off-by: Tomi Valkeinen <tomi.valkeinen at ti.com>
> ---
> 
> Based on Laurent's recent omapdrm series.
> 
>  drivers/gpu/drm/omapdrm/dss/dsi.c | 50 +++++++++++++++++++++++++++++++----
>  1 file changed, 45 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/omapdrm/dss/dsi.c
> b/drivers/gpu/drm/omapdrm/dss/dsi.c index a66d2b1a6c74..1f0b29af9b86 100644
> --- a/drivers/gpu/drm/omapdrm/dss/dsi.c
> +++ b/drivers/gpu/drm/omapdrm/dss/dsi.c
> @@ -2139,14 +2139,51 @@ static int dsi_omap4_mux_pads(struct dsi_data *dsi,
> unsigned int lanes) return 0;
>  }
> 
> +#define OMAP5_DSIPHY_SYSCON_OFFSET	0x74
> +
> +#define OMAP5_DSI1_LANEENABLE_SHIFT	24
> +#define OMAP5_DSI2_LANEENABLE_SHIFT	19
> +#define OMAP5_DSI_LANEENABLE_MASK	0x1f
> +
> +static int dsi_omap5_mux_pads(struct dsi_data *dsi, unsigned int lanes)
> +{
> +	u32 enable_mask, enable_shift, reg;
> +
> +	if (!dsi->syscon)
> +		return 0;

The purpose of this check in dsi_omap4_mux_pads() was to handle the SoCs that 
don't require any driver action to mux the DSI pins. Now that 
dsi_enable_pads() and dsi_disable_pads() have new SoC checks, this isn't 
needed anymore, dsi->syscon can't be NULL on OMAP4 or OMAP5.

> +	if (dsi->module_id == 0)
> +		enable_shift = OMAP5_DSI1_LANEENABLE_SHIFT;
> +	else if (dsi->module_id == 1)
> +		enable_shift = OMAP5_DSI2_LANEENABLE_SHIFT;
> +	else
> +		return -ENODEV;
> +
> +	enable_mask = OMAP5_DSI_LANEENABLE_MASK << enable_shift;
> +
> +	regmap_read(dsi->syscon, OMAP5_DSIPHY_SYSCON_OFFSET, &reg);
> +	reg &= ~enable_mask;
> +	reg |= (lanes << enable_shift) & enable_mask;
> +	regmap_write(dsi->syscon, OMAP5_DSIPHY_SYSCON_OFFSET, reg);
> +
> +	return 0;
> +}
> +
>  static int dsi_enable_pads(struct dsi_data *dsi, unsigned int lane_mask)
>  {
> -	return dsi_omap4_mux_pads(dsi, lane_mask);
> +	if (dsi->data->model == DSI_MODEL_OMAP4)
> +		return dsi_omap4_mux_pads(dsi, lane_mask);
> +	if (dsi->data->model == DSI_MODEL_OMAP5)
> +		return dsi_omap5_mux_pads(dsi, lane_mask);
> +	return 0;
>  }
> 
>  static void dsi_disable_pads(struct dsi_data *dsi)
>  {
> -	dsi_omap4_mux_pads(dsi, 0);
> +	if (dsi->data->model == DSI_MODEL_OMAP4)
> +		dsi_omap4_mux_pads(dsi, 0);
> +	if (dsi->data->model == DSI_MODEL_OMAP4)

Did you mean DSI_MODEL_OMAP5 ? As the two are mutually exclusive, I would use 
an "else if".

> +		dsi_omap5_mux_pads(dsi, 0);
>  }
> 
>  static int dsi_cio_init(struct platform_device *dsidev)
> @@ -5480,14 +5517,17 @@ static int dsi_bind(struct device *dev, struct
> device *master, void *data)
> 
>  	dsi->module_id = d->id;
> 
> -	if (dsi->data->model == DSI_MODEL_OMAP4) {
> +	if (dsi->data->model == DSI_MODEL_OMAP4 ||
> +	    dsi->data->model == DSI_MODEL_OMAP5) {
>  		struct device_node *np;
> 
>  		/*
> -		 * The OMAP4 display DT bindings don't reference the padconf
> +		 * The OMAP4/5 display DT bindings don't reference the padconf
>  		 * syscon. Our only option to retrieve it is to find it by 
name.
>  		 */
> -		np = of_find_node_by_name(NULL, "omap4_padconf_global");
> +		np = of_find_node_by_name(NULL,
> +			dsi->data->model == DSI_MODEL_OMAP4 ?
> +			"omap4_padconf_global" : "omap5_padconf_global");
>  		if (!np)
>  			return -ENODEV;

-- 
Regards,

Laurent Pinchart