Re: [PATCH v2] drm/msm/hdmi: Use pinctrl in HDMI driver

From: "Stéphane Viau"
Date: Tue Jun 02 2015 - 11:42:55 EST


>
> On Tue, 2015-06-02 at 10:12 -0500, "Stéphane Viau" wrote:
>> Hi Ivan,
>>
>> > Hi Stephane,
>> >
>> > On Mon, 2015-06-01 at 16:28 -0400, Stephane Viau wrote:
>> > > Some targets (eg: msm8994) use the pinctrl framework to configure
>> > > interface pins. This change adds support for initialization and
>> > > pinctrl active/sleep state control for the HDMI driver.
>> > >
>> > > Signed-off-by: Stephane Viau <sviau@xxxxxxxxxxxxxx>
>> > > ---
>> > > v2:
>> > > - Add devicetree binding documentation for pinctrl property [Ivan]
>> > > - Use pinctrl framework's PINCTRL_STATE_DEFAULT/SLEEP states [Ivan]
>> > >
>> >
>> > <snip>
>> >
>> > > static int hdmi_bind(struct device *dev, struct device *master,
>> void
>> > > *data)
>> > > @@ -365,6 +379,7 @@ static int hdmi_bind(struct device *dev, struct
>> > > device *master, void *data)
>> > > #ifdef CONFIG_OF
>> > > struct device_node *of_node = dev->of_node;
>> > > const struct of_device_id *match;
>> > > + struct pinctrl *pinctrl;
>> > >
>> > > match = of_match_node(dt_match, of_node);
>> > > if (match && match->data) {
>> > > @@ -383,6 +398,18 @@ static int hdmi_bind(struct device *dev, struct
>> > > device *master, void *data)
>> > > hdmi_cfg->mux_sel_gpio = get_gpio(dev, of_node,
>> > > "qcom,hdmi-tx-mux-sel");
>> > > hdmi_cfg->mux_lpm_gpio = get_gpio(dev, of_node,
>> > > "qcom,hdmi-tx-mux-lpm");
>> > >
>> > > + /* not all targets have pinctrl, do not fail in case of
>> error:
>> > > */
>> > > + pinctrl = devm_pinctrl_get(dev);
>> >
>> > Probably I have to be more explicit. Why not using pins binding
>> handled in
>> > driver
>> > really_probe()? I have to admit that I am not familiar with DRM
>> subsystem.
>>
>> This would work, indeed, for default/sleep/idle states.
>>
>> I actually had in mind that we'd need to keep track of HDMI pinctrl
>> states
>> because we may need to add a couple more in the near future in order to
>> independently enable/disable certain parts of the HDMI controller (eg:
>> HPD, DDC, CEC..).
>>
>> Each of this HW sub-sections of the controller are driven by a different
>> "pin" in the downstream driver... But since this is nowhere close to
>> being
>> upstream-ed yet, I'll go ahead with your idea of using the common pins
>> binding (v3 to follow).
>
> v3? Why we need a patch if we already have required support?

To actually call pinctrl_pm_select_default/sleep_state() from the
drm/msm/hdmi driver (in hdp_enable/disable() functions).

Stephane.

>
> Regards,
> Ivan
>
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