[RFC,06/11] drm/bridge: analogix-anx78xx: add support for avdd33 regulator

Submitted by Brian Masney on Aug. 15, 2019, 12:48 a.m.

Details

Message ID 20190815004854.19860-7-masneyb@onstation.org
State New
Headers show
Series "ARM: dts: qcom: msm8974: add support for external display" ( rev: 1 ) in Freedreno

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Commit Message

Brian Masney Aug. 15, 2019, 12:48 a.m.
Add support for the avdd33 regulator to the analogix-anx78xx driver.
Note that the regulator is currently enabled during driver probe and
disabled when the driver is removed. This is currently how the
downstream MSM kernel sources do this.

Let's not merge this upstream for the mean time until I get the external
display fully working on the Nexus 5 and then I can submit proper
support then that powers down this regulator in the power off function.

Signed-off-by: Brian Masney <masneyb@onstation.org>
---
 drivers/gpu/drm/bridge/analogix-anx78xx.c | 33 +++++++++++++++++++++++
 1 file changed, 33 insertions(+)

Patch hide | download patch | download mbox

diff --git a/drivers/gpu/drm/bridge/analogix-anx78xx.c b/drivers/gpu/drm/bridge/analogix-anx78xx.c
index 8daee6b1fa88..48adf010816c 100644
--- a/drivers/gpu/drm/bridge/analogix-anx78xx.c
+++ b/drivers/gpu/drm/bridge/analogix-anx78xx.c
@@ -48,6 +48,7 @@  static const u8 anx78xx_i2c_addresses[] = {
 
 struct anx78xx_platform_data {
 	struct regulator *dvdd10;
+	struct regulator *avdd33;
 	struct gpio_desc *gpiod_hpd;
 	struct gpio_desc *gpiod_pd;
 	struct gpio_desc *gpiod_reset;
@@ -707,10 +708,42 @@  static int anx78xx_start(struct anx78xx *anx78xx)
 	return err;
 }
 
+static void anx78xx_disable_regulator_action(void *_data)
+{
+	struct anx78xx_platform_data *pdata = _data;
+
+	regulator_disable(pdata->avdd33);
+}
+
 static int anx78xx_init_pdata(struct anx78xx *anx78xx)
 {
 	struct anx78xx_platform_data *pdata = &anx78xx->pdata;
 	struct device *dev = &anx78xx->client->dev;
+	int err;
+
+	/* 3.3V digital core power regulator  */
+	pdata->avdd33 = devm_regulator_get(dev, "avdd33");
+	if (IS_ERR(pdata->avdd33)) {
+		err = PTR_ERR(pdata->avdd33);
+		if (err != -EPROBE_DEFER)
+			DRM_ERROR("avdd33 regulator not found\n");
+
+		return err;
+	}
+
+	err = regulator_enable(pdata->avdd33);
+	if (err) {
+		DRM_ERROR("Failed to enable avdd33 regulator: %d\n", err);
+		return err;
+	}
+
+	err = devm_add_action(dev, anx78xx_disable_regulator_action,
+			      pdata);
+	if (err < 0) {
+		dev_err(dev, "Failed to setup regulator cleanup action %d\n",
+			err);
+		return err;
+	}
 
 	/* 1.0V digital core power regulator  */
 	pdata->dvdd10 = devm_regulator_get(dev, "dvdd10");

Comments

On Thu, Aug 15, 2019 at 2:49 AM Brian Masney <masneyb@onstation.org> wrote:

> Add support for the avdd33 regulator to the analogix-anx78xx driver.
> Note that the regulator is currently enabled during driver probe and
> disabled when the driver is removed. This is currently how the
> downstream MSM kernel sources do this.
>
> Let's not merge this upstream for the mean time until I get the external
> display fully working on the Nexus 5 and then I can submit proper
> support then that powers down this regulator in the power off function.
>
> Signed-off-by: Brian Masney <masneyb@onstation.org>

> +static void anx78xx_disable_regulator_action(void *_data)
> +{
> +       struct anx78xx_platform_data *pdata = _data;
> +
> +       regulator_disable(pdata->avdd33);
> +}
(...)
> +       err = devm_add_action(dev, anx78xx_disable_regulator_action,
> +                             pdata);

Clever idea. Good for initial support, probably later on it would
need to be reworked using runtime PM so it's not constantly
powered up.

See for example how I try to push down power dissipation
of sensors in 3d838118c6aa.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij
On Thu, Aug 15, 2019 at 10:22:45AM +0200, Linus Walleij wrote:
> On Thu, Aug 15, 2019 at 2:49 AM Brian Masney <masneyb@onstation.org> wrote:
> 
> > Add support for the avdd33 regulator to the analogix-anx78xx driver.
> > Note that the regulator is currently enabled during driver probe and
> > disabled when the driver is removed. This is currently how the
> > downstream MSM kernel sources do this.
> >
> > Let's not merge this upstream for the mean time until I get the external
> > display fully working on the Nexus 5 and then I can submit proper
> > support then that powers down this regulator in the power off function.
> >
> > Signed-off-by: Brian Masney <masneyb@onstation.org>
> 
> > +static void anx78xx_disable_regulator_action(void *_data)
> > +{
> > +       struct anx78xx_platform_data *pdata = _data;
> > +
> > +       regulator_disable(pdata->avdd33);
> > +}
> (...)
> > +       err = devm_add_action(dev, anx78xx_disable_regulator_action,
> > +                             pdata);
> 
> Clever idea. Good for initial support, probably later on it would
> need to be reworked using runtime PM so it's not constantly
> powered up.

Yes, that's my plan. I suspect that I may have a regulator disabled
somewhere so I was planning to leave this on all the time for the time
being to match the downstream behavior until I get the hot plug detect
GPIO working.

> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Thanks,

Brian