media: i2c: imx319: Support device probe in non-zero ACPI D state

Tell ACPI device PM code that the driver supports the device being in
non-zero ACPI D state when the driver's probe function is entered.

Signed-off-by: Rajmohan Mani <[e-mail]>
Signed-off-by: Sakari Ailus <[e-mail]>
Reviewed-by: Tomasz Figa <[e-mail]>
Reviewed-by: Bingbu Cao <[e-mail]>
Signed-off-by: Rafael J. Wysocki <[e-mail]>

drivers/media/i2c/imx319.c

···
 
 	/* Streaming on/off */
 	bool streaming;
+	/* True if the device has been identified */
+	bool identified;
 };
 
 static const struct imx319_reg imx319_global_regs[] = {
···
 	return 0;
 }
 
+/* Verify chip ID */
+static int imx319_identify_module(struct imx319 *imx319)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&imx319->sd);
+	int ret;
+	u32 val;
+
+	if (imx319->identified)
+		return 0;
+
+	ret = imx319_read_reg(imx319, IMX319_REG_CHIP_ID, 2, &val);
+	if (ret)
+		return ret;
+
+	if (val != IMX319_CHIP_ID) {
+		dev_err(&client->dev, "chip id mismatch: %x!=%x",
+			IMX319_CHIP_ID, val);
+		return -EIO;
+	}
+
+	imx319->identified = true;
+
+	return 0;
+}
+
 /* Start streaming */
 static int imx319_start_streaming(struct imx319 *imx319)
 {
 	struct i2c_client *client = v4l2_get_subdevdata(&imx319->sd);
 	const struct imx319_reg_list *reg_list;
 	int ret;
+
+	ret = imx319_identify_module(imx319);
+	if (ret)
+		return ret;
 
 	/* Global Setting */
 	reg_list = &imx319_global_setting;
···
 	imx319_stop_streaming(imx319);
 	imx319->streaming = 0;
 	return ret;
-}
-
-/* Verify chip ID */
-static int imx319_identify_module(struct imx319 *imx319)
-{
-	struct i2c_client *client = v4l2_get_subdevdata(&imx319->sd);
-	int ret;
-	u32 val;
-
-	ret = imx319_read_reg(imx319, IMX319_REG_CHIP_ID, 2, &val);
-	if (ret)
-		return ret;
-
-	if (val != IMX319_CHIP_ID) {
-		dev_err(&client->dev, "chip id mismatch: %x!=%x",
-			IMX319_CHIP_ID, val);
-		return -EIO;
-	}
-
-	return 0;
 }
 
 static const struct v4l2_subdev_core_ops imx319_subdev_core_ops = {
···
 static int imx319_probe(struct i2c_client *client)
 {
 	struct imx319 *imx319;
+	bool full_power;
 	int ret;
 	u32 i;
 
···
 	/* Initialize subdev */
 	v4l2_i2c_subdev_init(&imx319->sd, client, &imx319_subdev_ops);
 
-	/* Check module identity */
-	ret = imx319_identify_module(imx319);
-	if (ret) {
-		dev_err(&client->dev, "failed to find sensor: %d", ret);
-		goto error_probe;
+	full_power = acpi_dev_state_d0(&client->dev);
+	if (full_power) {
+		/* Check module identity */
+		ret = imx319_identify_module(imx319);
+		if (ret) {
+			dev_err(&client->dev, "failed to find sensor: %d", ret);
+			goto error_probe;
+		}
 	}
 
 	imx319->hwcfg = imx319_get_hwcfg(&client->dev);
···
 	if (ret < 0)
 		goto error_media_entity;
 
-	/*
-	 * Device is already turned on by i2c-core with ACPI domain PM.
-	 * Enable runtime PM and turn off the device.
-	 */
-	pm_runtime_set_active(&client->dev);
+	/* Set the device's state to active if it's in D0 state. */
+	if (full_power)
+		pm_runtime_set_active(&client->dev);
 	pm_runtime_enable(&client->dev);
 	pm_runtime_idle(&client->dev);
 
···
 	},
 	.probe_new = imx319_probe,
 	.remove = imx319_remove,
+	.flags = I2C_DRV_ACPI_WAIVE_D0_PROBE,
 };
 module_i2c_driver(imx319_i2c_driver);