linux-kernel - [PATCH 2/2] drm/bridge: anx7625: disable regulators when power off

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Message-Id: <20201112083704.1173908-2-hsinyi@chromium.org>
Date:   Thu, 12 Nov 2020 16:37:04 +0800
From:   Hsin-Yi Wang <hsinyi@...omium.org>
To:     Xin Ji <xji@...logixsemi.com>, Sam Ravnborg <sam@...nborg.org>,
        Rob Herring <robh+dt@...nel.org>
Cc:     David Airlie <airlied@...ux.ie>, Daniel Vetter <daniel@...ll.ch>,
        Hsin-Yi Wang <hsinyi@...omium.org>,
        dri-devel@...ts.freedesktop.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, Andrzej Hajda <a.hajda@...sung.com>,
        Neil Armstrong <narmstrong@...libre.com>,
        Laurent Pinchart <Laurent.pinchart@...asonboard.com>,
        Jonas Karlman <jonas@...boo.se>,
        Jernej Skrabec <jernej.skrabec@...l.net>
Subject: [PATCH 2/2] drm/bridge: anx7625: disable regulators when power off

When suspending the driver, anx7625_power_standby() will be called to
turn off reset-gpios and enable-gpios. However, power supplies are not
disabled. To save power, the driver can get the power supply regulators
and turn off them in anx7625_power_standby().

Signed-off-by: Hsin-Yi Wang <hsinyi@...omium.org>
---
 drivers/gpu/drm/bridge/analogix/anx7625.c | 25 +++++++++++++++++++++++
 drivers/gpu/drm/bridge/analogix/anx7625.h |  1 +
 2 files changed, 26 insertions(+)

diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
index 65cc05982f82..eb9c4cc2504a 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
@@ -11,6 +11,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/workqueue.h>
@@ -875,12 +876,20 @@ static int sp_tx_edid_read(struct anx7625_data *ctx,
 static void anx7625_power_on(struct anx7625_data *ctx)
 {
 	struct device *dev = &ctx->client->dev;
+	int ret;
 
 	if (!ctx->pdata.low_power_mode) {
 		DRM_DEV_DEBUG_DRIVER(dev, "not low power mode!\n");
 		return;
 	}
 
+	ret = regulator_bulk_enable(ARRAY_SIZE(ctx->pdata.supplies),
+				    ctx->pdata.supplies);
+	if (ret < 0) {
+		DRM_DEV_DEBUG_DRIVER(dev, "cannot enable regulators %d\n", ret);
+		return;
+	}
+
 	/* Power on pin enable */
 	gpiod_set_value(ctx->pdata.gpio_p_on, 1);
 	usleep_range(10000, 11000);
@@ -894,6 +903,7 @@ static void anx7625_power_on(struct anx7625_data *ctx)
 static void anx7625_power_standby(struct anx7625_data *ctx)
 {
 	struct device *dev = &ctx->client->dev;
+	int ret;
 
 	if (!ctx->pdata.low_power_mode) {
 		DRM_DEV_DEBUG_DRIVER(dev, "not low power mode!\n");
@@ -904,6 +914,12 @@ static void anx7625_power_standby(struct anx7625_data *ctx)
 	usleep_range(1000, 1100);
 	gpiod_set_value(ctx->pdata.gpio_p_on, 0);
 	usleep_range(1000, 1100);
+
+	ret = regulator_bulk_disable(ARRAY_SIZE(ctx->pdata.supplies),
+				     ctx->pdata.supplies);
+	if (ret < 0)
+		DRM_DEV_DEBUG_DRIVER(dev, "cannot disable regulators %d\n", ret);
+
 	DRM_DEV_DEBUG_DRIVER(dev, "power down\n");
 }
 
@@ -1742,6 +1758,15 @@ static int anx7625_i2c_probe(struct i2c_client *client,
 	platform->client = client;
 	i2c_set_clientdata(client, platform);
 
+	pdata->supplies[0].supply = "vdd10";
+	pdata->supplies[1].supply = "vdd18";
+	pdata->supplies[2].supply = "vdd33";
+	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(pdata->supplies),
+				      pdata->supplies);
+	if (ret) {
+		DRM_DEV_ERROR(dev, "fail to get power supplies: %d\n", ret);
+		return ret;
+	}
 	anx7625_init_gpio(platform);
 
 	atomic_set(&platform->power_status, 0);
diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.h b/drivers/gpu/drm/bridge/analogix/anx7625.h
index 193ad86c5450..e4a086b3a3d7 100644
--- a/drivers/gpu/drm/bridge/analogix/anx7625.h
+++ b/drivers/gpu/drm/bridge/analogix/anx7625.h
@@ -350,6 +350,7 @@ struct s_edid_data {
 struct anx7625_platform_data {
 	struct gpio_desc *gpio_p_on;
 	struct gpio_desc *gpio_reset;
+	struct regulator_bulk_data supplies[3];
 	struct drm_bridge *panel_bridge;
 	int intp_irq;
 	u32 low_power_mode;
-- 
2.29.2.222.g5d2a92d10f8-goog