[PATCH] drm/panel: st7701: Add prepare_prev_first flag to drm_panel

[Jessica Zhang]

On 11/24/2024 2:48 PM, Marek Vasut wrote:
> The DSI host must be enabled for the panel to be initialized in
> prepare(). Set the prepare_prev_first flag to guarantee this.
> This fixes the panel operation on NXP i.MX8MP SoC / Samsung DSIM
> DSI host.

Hi Marek,

LGTM.

Reviewed-by: Jessica Zhang <quic_jesszhan at quicinc.com>

Thanks,

Jessica Zhang

> 
> Fixes: 849b2e3ff969 ("drm/panel: Add Sitronix ST7701 panel driver")
> Signed-off-by: Marek Vasut <marex at denx.de>
> ---
> Cc: Chris Morgan <macromorgan at hotmail.com>
> Cc: David Airlie <airlied at gmail.com>
> Cc: Hironori KIKUCHI <kikuchan98 at gmail.com>
> Cc: Jagan Teki <jagan at amarulasolutions.com>
> Cc: Jessica Zhang <quic_jesszhan at quicinc.com>
> Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> Cc: Maxime Ripard <mripard at kernel.org>
> Cc: Neil Armstrong <neil.armstrong at linaro.org>
> Cc: Simona Vetter <simona at ffwll.ch>
> Cc: Thomas Zimmermann <tzimmermann at suse.de>
> Cc: dri-devel at lists.freedesktop.org
> Cc: stable at vger.kernel.org # v6.2+
> ---
> Note that the prepare_prev_first flag was added in Linux 6.2.y commit
> 5ea6b1702781 ("drm/panel: Add prepare_prev_first flag to drm_panel"),
> hence the CC stable v6.2+, even if the Fixes tag points to a commit
> in Linux 5.1.y .
> ---
>   drivers/gpu/drm/panel/panel-sitronix-st7701.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/panel/panel-sitronix-st7701.c b/drivers/gpu/drm/panel/panel-sitronix-st7701.c
> index eef03d04e0cd2..1f72ef7ca74c9 100644
> --- a/drivers/gpu/drm/panel/panel-sitronix-st7701.c
> +++ b/drivers/gpu/drm/panel/panel-sitronix-st7701.c
> @@ -1177,6 +1177,7 @@ static int st7701_probe(struct device *dev, int connector_type)
>   		return dev_err_probe(dev, ret, "Failed to get orientation\n");
>   
>   	drm_panel_init(&st7701->panel, dev, &st7701_funcs, connector_type);
> +	st7701->panel.prepare_prev_first = true;
>   
>   	/**
>   	 * Once sleep out has been issued, ST7701 IC required to wait 120ms
> -- 
> 2.45.2
>