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From: Andy Shevchenko <>
To: Hans de Goede <>
Cc: "Jani Nikula" <>,
	"Joonas Lahtinen" <>,
	"Rodrigo Vivi" <>,
	"Ville Syrjälä" <>,
	"Mika Westerberg" <>,
	"Bartosz Golaszewski" <>,
	"Linus Walleij" <>,
	intel-gfx <>,,,
Subject: Re: [PATCH 0/2] drm/i915/vlv_dsi: Control panel and backlight enable GPIOs on BYT
Date: Fri, 29 Nov 2019 22:07:39 +0200
Message-ID: <> (raw)
In-Reply-To: <>

On Fri, Nov 29, 2019 at 07:58:34PM +0100, Hans de Goede wrote:
> Hi All,
> On Bay Trail devices the MIPI power on/off sequences for DSI LCD panels
> do not control the LCD panel- and backlight-enable GPIOs. So far, when
> the VBT indicates we should use the SoC for backlight control, we have
> been relying on these GPIOs being configured as output and driven high by
> the Video BIOS (GOP) when it initializes the panel.
> This does not work when the device is booted with a HDMI monitor connected
> as then the GOP will initialize the HDMI instead of the panel, leaving the
> panel black, even though the i915 driver tries to output an image to it.
> Likewise on some device-models when the GOP does not initialize the DSI
> panel it also leaves the mux of the PWM0 pin in generic GPIO mode instead
> of muxing it to the PWM controller.
> This series contains 2 patches which together fix this.
> To avoid new errors in the intel-gfx CI (assuming there is atleast 1
> BYT device there with a DSI panel), we need both of these patches to
> be merged through the drm-intel tree.
> Unfortunately there is some churn currently going on in the
> pinctrl-baytrail.c code, but not in the part of the file which this
> touches, so merging the pinctrl-baytrail.c changes through the
> drm-intel tree should not lead to conflicts later.
> Andy, Mika, assuming you are happy with the changes, can I get your ack
> for merging the pinctrl-baytrail patch throught the drm-inteol tree?

I'm not okay with this. I will tell more next week how I see this to be
implemented in a better way.

Happy Black Friday! :-)

With Best Regards,
Andy Shevchenko

      parent reply index

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-29 18:58 Hans de Goede
2019-11-29 18:58 ` [PATCH 1/2] pinctrl: baytrail: Add GPIO lookup and pinctrl-map for i915 DSI panel ctrl Hans de Goede
2019-12-02 11:39   ` Linus Walleij
2019-12-02 13:09   ` Andy Shevchenko
2019-11-29 18:58 ` [PATCH 2/2] drm/i915/vlv_dsi: Control panel and backlight enable GPIOs on BYT Hans de Goede
2019-12-02 11:21   ` Linus Walleij
2019-12-02 11:53     ` Jani Nikula
2019-12-02 15:49       ` Hans de Goede
2019-12-11  0:24         ` Linus Walleij
2019-12-11 17:32           ` Hans de Goede
2019-11-29 20:07 ` Andy Shevchenko [this message]

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