media: ov13b10: add PM control support based on power resources

On ACPI based platforms, the ov13b10 camera sensor need to be powered
up by acquire the PM resource from INT3472. INT3472 will register one
regulator 'avdd', one reset gpio and clock source for ov13b10.
Add 2 power interfaces that are registered as runtime PM callbacks.

Signed-off-by: Bingbu Cao <bingbu.cao@intel.com>
Signed-off-by: Hao Yao <hao.yao@intel.com>
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/media/i2c/ov13b10.c

@@ -2,6 +2,9 @@
 // Copyright (c) 2021 Intel Corporation.
 
 #include <linux/acpi.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
@@ -573,6 +576,11 @@ struct ov13b10 {
 	struct media_pad pad;
 
 	struct v4l2_ctrl_handler ctrl_handler;
+
+	struct clk *img_clk;
+	struct regulator *avdd;
+	struct gpio_desc *reset;
+
 	/* V4L2 Controls */
 	struct v4l2_ctrl *link_freq;
 	struct v4l2_ctrl *pixel_rate;
@@ -1051,6 +1059,49 @@ static int ov13b10_identify_module(struct ov13b10 *ov13b)
 	return 0;
 }
 
+static int ov13b10_power_off(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct ov13b10 *ov13b10 = to_ov13b10(sd);
+
+	gpiod_set_value_cansleep(ov13b10->reset, 1);
+
+	if (ov13b10->avdd)
+		regulator_disable(ov13b10->avdd);
+
+	clk_disable_unprepare(ov13b10->img_clk);
+
+	return 0;
+}
+
+static int ov13b10_power_on(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct ov13b10 *ov13b10 = to_ov13b10(sd);
+	int ret;
+
+	ret = clk_prepare_enable(ov13b10->img_clk);
+	if (ret < 0) {
+		dev_err(dev, "failed to enable imaging clock: %d", ret);
+		return ret;
+	}
+
+	if (ov13b10->avdd) {
+		ret = regulator_enable(ov13b10->avdd);
+		if (ret < 0) {
+			dev_err(dev, "failed to enable avdd: %d", ret);
+			clk_disable_unprepare(ov13b10->img_clk);
+			return ret;
+		}
+	}
+
+	gpiod_set_value_cansleep(ov13b10->reset, 0);
+	/* 5ms to wait ready after XSHUTDN assert */
+	usleep_range(5000, 5500);
+
+	return 0;
+}
+
 static int ov13b10_start_streaming(struct ov13b10 *ov13b)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(&ov13b->sd);
@@ -1145,7 +1196,7 @@ err_unlock:
 	return ret;
 }
 
-static int __maybe_unused ov13b10_suspend(struct device *dev)
+static int ov13b10_suspend(struct device *dev)
 {
 	struct v4l2_subdev *sd = dev_get_drvdata(dev);
 	struct ov13b10 *ov13b = to_ov13b10(sd);
@@ -1153,26 +1204,35 @@ static int __maybe_unused ov13b10_suspend(struct device *dev)
 	if (ov13b->streaming)
 		ov13b10_stop_streaming(ov13b);
 
+	ov13b10_power_off(dev);
+
 	return 0;
 }
 
-static int __maybe_unused ov13b10_resume(struct device *dev)
+static int ov13b10_resume(struct device *dev)
 {
 	struct v4l2_subdev *sd = dev_get_drvdata(dev);
 	struct ov13b10 *ov13b = to_ov13b10(sd);
 	int ret;
 
+	ret = ov13b10_power_on(dev);
+	if (ret)
+		goto pm_fail;
+
 	if (ov13b->streaming) {
 		ret = ov13b10_start_streaming(ov13b);
 		if (ret)
-			goto error;
+			goto stop_streaming;
 	}
 
 	return 0;
 
-error:
+stop_streaming:
 	ov13b10_stop_streaming(ov13b);
+	ov13b10_power_off(dev);
+pm_fail:
 	ov13b->streaming = false;
+
 	return ret;
 }
 
@@ -1317,6 +1377,34 @@ static void ov13b10_free_controls(struct ov13b10 *ov13b)
 	mutex_destroy(&ov13b->mutex);
 }
 
+static int ov13b10_get_pm_resources(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct ov13b10 *ov13b = to_ov13b10(sd);
+	int ret;
+
+	ov13b->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+	if (IS_ERR(ov13b->reset))
+		return dev_err_probe(dev, PTR_ERR(ov13b->reset),
+				     "failed to get reset gpio\n");
+
+	ov13b->img_clk = devm_clk_get_optional(dev, NULL);
+	if (IS_ERR(ov13b->img_clk))
+		return dev_err_probe(dev, PTR_ERR(ov13b->img_clk),
+				     "failed to get imaging clock\n");
+
+	ov13b->avdd = devm_regulator_get_optional(dev, "avdd");
+	if (IS_ERR(ov13b->avdd)) {
+		ret = PTR_ERR(ov13b->avdd);
+		ov13b->avdd = NULL;
+		if (ret != -ENODEV)
+			return dev_err_probe(dev, ret,
+					     "failed to get avdd regulator\n");
+	}
+
+	return 0;
+}
+
 static int ov13b10_check_hwcfg(struct device *dev)
 {
 	struct v4l2_fwnode_endpoint bus_cfg = {
@@ -1407,13 +1495,23 @@ static int ov13b10_probe(struct i2c_client *client)
 	/* Initialize subdev */
 	v4l2_i2c_subdev_init(&ov13b->sd, client, &ov13b10_subdev_ops);
 
+	ret = ov13b10_get_pm_resources(&client->dev);
+	if (ret)
+		return ret;
+
 	full_power = acpi_dev_state_d0(&client->dev);
 	if (full_power) {
+		ov13b10_power_on(&client->dev);
+		if (ret) {
+			dev_err(&client->dev, "failed to power on\n");
+			return ret;
+		}
+
 		/* Check module identity */
 		ret = ov13b10_identify_module(ov13b);
 		if (ret) {
 			dev_err(&client->dev, "failed to find sensor: %d\n", ret);
-			return ret;
+			goto error_power_off;
 		}
 	}
 
@@ -1422,7 +1520,7 @@ static int ov13b10_probe(struct i2c_client *client)
 
 	ret = ov13b10_init_controls(ov13b);
 	if (ret)
-		return ret;
+		goto error_power_off;
 
 	/* Initialize subdev */
 	ov13b->sd.internal_ops = &ov13b10_internal_ops;
@@ -1462,6 +1560,9 @@ error_handler_free:
 	ov13b10_free_controls(ov13b);
 	dev_err(&client->dev, "%s failed:%d\n", __func__, ret);
 
+error_power_off:
+	ov13b10_power_off(&client->dev);
+
 	return ret;
 }
 
@@ -1477,9 +1578,8 @@ static void ov13b10_remove(struct i2c_client *client)
 	pm_runtime_disable(&client->dev);
 }
 
-static const struct dev_pm_ops ov13b10_pm_ops = {
+static DEFINE_RUNTIME_DEV_PM_OPS(ov13b10_pm_ops, ov13b10_suspend,
-	SET_SYSTEM_SLEEP_PM_OPS(ov13b10_suspend, ov13b10_resume)
+				 ov13b10_resume, NULL);
-};
 
 #ifdef CONFIG_ACPI
 static const struct acpi_device_id ov13b10_acpi_ids[] = {
@@ -1494,7 +1594,7 @@ MODULE_DEVICE_TABLE(acpi, ov13b10_acpi_ids);
 static struct i2c_driver ov13b10_i2c_driver = {
 	.driver = {
 		.name = "ov13b10",
-		.pm = &ov13b10_pm_ops,
+		.pm = pm_ptr(&ov13b10_pm_ops),
 		.acpi_match_table = ACPI_PTR(ov13b10_acpi_ids),
 	},
 	.probe = ov13b10_probe,