[PATCH 04/10] drm/msm/dsi: dsi_host: Fix DSI index detection when version clash occurs

[Dmitry Baryshkov]

On 11/02/2023 13:51, Konrad Dybcio wrote:
> Now that msm_dsi_config is ready to accept multiple sets of registers
> (where array[n][idx] holds the base registers of DSI(idx) for the nth
> entry), loop through all available configs to resolve hw version
> clashes.
> 
> Fixes: 32280d66fd44 ("drm/msm/dsi: Don't get DSI index from DT")

Do we really want to backport this patch (and other patches from this 
series to older kernels?)

> Signed-off-by: Konrad Dybcio <konrad.dybcio at linaro.org>
> ---
>   drivers/gpu/drm/msm/dsi/dsi_cfg.h  |  1 +
>   drivers/gpu/drm/msm/dsi/dsi_host.c | 12 +++++++-----
>   2 files changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_cfg.h b/drivers/gpu/drm/msm/dsi/dsi_cfg.h
> index 03493cc6b772..4a47705234bd 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_cfg.h
> +++ b/drivers/gpu/drm/msm/dsi/dsi_cfg.h
> @@ -43,6 +43,7 @@ struct msm_dsi_config {
>   	const int num_bus_clks;
>   	/* Allow + 1 entry for the zero-terminator */
>   	const resource_size_t io_start[VARIANTS_MAX][DSI_MAX + 1];
> +	const int num_variants;
>   };
>   
>   struct msm_dsi_host_cfg_ops {
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c
> index f5092b4d0757..8dfa69bcff77 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_host.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c
> @@ -1862,16 +1862,18 @@ static int dsi_host_get_id(struct msm_dsi_host *msm_host)
>   	struct platform_device *pdev = msm_host->pdev;
>   	const struct msm_dsi_config *cfg = msm_host->cfg_hnd->cfg;
>   	struct resource *res;
> -	int i;
> +	int i, j, num_variants;
>   
>   	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dsi_ctrl");
>   	if (!res)
>   		return -EINVAL;
>   
> -	for (i = 0; cfg->io_start[0][i]; i++) {
> -		if (cfg->io_start[0][i] == res->start)
> -			return i;
> -	}
> +	num_variants = cfg->num_variants ? cfg->num_variants : 1;
> +
> +	for (i = 0; i < num_variants; i++)
> +		for (j = 0; cfg->io_start[i][j]; j++)
> +			if (cfg->io_start[i][j] == res->start)
> +				return j;
>   
>   	return -EINVAL;
>   }

Please squash this together with the patch 'drm/msm/dsi: Turn 
msm_dsi_config::io_start into a 2d array'.

-- 
With best wishes
Dmitry