[PATCH] drm/stm: dsi: check hardware version

[Philippe CORNU]

Dear Yannick,
Thank you for your patch,

Acked-by: Philippe Cornu <philippe.cornu at st.com>

Dear Benjamin,
If you are fine with this patch, please push it *after* the patch named 
"drm/stm: dsi: add support of an optional regulator" (if I well 
understood those two patches)

Thank you
Philippe :-)


On 5/10/19 5:02 PM, Yannick Fertré wrote:
> Check version of DSI hardware IP. Only versions 1.30 & 1.31
> are supported.
> 
> Signed-off-by: Yannick Fertré <yannick.fertre at st.com>
> ---
>   drivers/gpu/drm/stm/dw_mipi_dsi-stm.c | 24 +++++++++++++++++++++++-
>   1 file changed, 23 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> index 22bd095..29105e9 100644
> --- a/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> +++ b/drivers/gpu/drm/stm/dw_mipi_dsi-stm.c
> @@ -227,7 +227,6 @@ dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
>   	u32 val;
>   
>   	/* Update lane capabilities according to hw version */
> -	dsi->hw_version = dsi_read(dsi, DSI_VERSION) & VERSION;
>   	dsi->lane_min_kbps = LANE_MIN_KBPS;
>   	dsi->lane_max_kbps = LANE_MAX_KBPS;
>   	if (dsi->hw_version == HWVER_131) {
> @@ -306,6 +305,7 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
>   {
>   	struct device *dev = &pdev->dev;
>   	struct dw_mipi_dsi_stm *dsi;
> +	struct clk *pclk;
>   	struct resource *res;
>   	int ret;
>   
> @@ -347,6 +347,28 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
>   		goto err_clk_get;
>   	}
>   
> +	pclk = devm_clk_get(dev, "pclk");
> +	if (IS_ERR(pclk)) {
> +		ret = PTR_ERR(pclk);
> +		DRM_ERROR("Unable to get peripheral clock: %d\n", ret);
> +		goto err_dsi_probe;
> +	}
> +
> +	ret = clk_prepare_enable(pclk);
> +	if (ret) {
> +		DRM_ERROR("%s: Failed to enable peripheral clk\n", __func__);
> +		goto err_dsi_probe;
> +	}
> +
> +	dsi->hw_version = dsi_read(dsi, DSI_VERSION) & VERSION;
> +	clk_disable_unprepare(pclk);
> +
> +	if (dsi->hw_version != HWVER_130 && dsi->hw_version != HWVER_131) {
> +		ret = -ENODEV;
> +		DRM_ERROR("bad dsi hardware version\n");
> +		goto err_dsi_probe;
> +	}
> +
>   	dw_mipi_dsi_stm_plat_data.base = dsi->base;
>   	dw_mipi_dsi_stm_plat_data.priv_data = dsi;
>   
>