Commit 0e014f1a authored by Bingbu Cao's avatar Bingbu Cao Committed by Mauro Carvalho Chehab
Browse files

media: ov8856: 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.

Also do identification on the first access of the device, whether in probe
or when starting streaming.

Signed-off-by: default avatarBingbu Cao <bingbu.cao@intel.com>
Signed-off-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent cbe0b3af

drivers/media/i2c/ov8856.c

+89 −73
Original line number Diff line number Diff line
@@ -1445,6 +1445,9 @@ struct ov8856 { 


	const struct ov8856_lane_cfg *priv_lane;

	u8 modes_size;



	/* True if the device has been identified */

	bool identified;

};



struct ov8856_lane_cfg {
@@ -1685,6 +1688,71 @@ static int ov8856_write_reg_list(struct ov8856 *ov8856, 
	return 0;

}



static int ov8856_identify_module(struct ov8856 *ov8856)

{

	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);

	int ret;

	u32 val;



	if (ov8856->identified)

		return 0;



	ret = ov8856_read_reg(ov8856, OV8856_REG_CHIP_ID,

			      OV8856_REG_VALUE_24BIT, &val);

	if (ret)

		return ret;



	if (val != OV8856_CHIP_ID) {

		dev_err(&client->dev, "chip id mismatch: %x!=%x",

			OV8856_CHIP_ID, val);

		return -ENXIO;

	}



	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,

			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);

	if (ret)

		return ret;



	ret = ov8856_write_reg(ov8856, OV8856_OTP_MODE_CTRL,

			       OV8856_REG_VALUE_08BIT, OV8856_OTP_MODE_AUTO);

	if (ret) {

		dev_err(&client->dev, "failed to set otp mode");

		return ret;

	}



	ret = ov8856_write_reg(ov8856, OV8856_OTP_LOAD_CTRL,

			       OV8856_REG_VALUE_08BIT,

			       OV8856_OTP_LOAD_CTRL_ENABLE);

	if (ret) {

		dev_err(&client->dev, "failed to enable load control");

		return ret;

	}



	ret = ov8856_read_reg(ov8856, OV8856_MODULE_REVISION,

			      OV8856_REG_VALUE_08BIT, &val);

	if (ret) {

		dev_err(&client->dev, "failed to read module revision");

		return ret;

	}



	dev_info(&client->dev, "OV8856 revision %x (%s) at address 0x%02x\n",

		 val,

		 val == OV8856_2A_MODULE ? "2A" :

		 val == OV8856_1B_MODULE ? "1B" : "unknown revision",

		 client->addr);



	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,

			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);

	if (ret) {

		dev_err(&client->dev, "failed to exit streaming mode");

		return ret;

	}



	ov8856->identified = true;



	return 0;

}



static int ov8856_update_digital_gain(struct ov8856 *ov8856, u32 d_gain)

{

	int ret;
@@ -1969,6 +2037,10 @@ static int ov8856_start_streaming(struct ov8856 *ov8856) 
	const struct ov8856_reg_list *reg_list;

	int link_freq_index, ret;



	ret = ov8856_identify_module(ov8856);

	if (ret)

		return ret;



	link_freq_index = ov8856->cur_mode->link_freq_index;

	reg_list = &ov8856->priv_lane->link_freq_configs[link_freq_index].reg_list;
@@ -2276,65 +2348,6 @@ static const struct v4l2_subdev_internal_ops ov8856_internal_ops = { 
	.open = ov8856_open,

};



static int ov8856_identify_module(struct ov8856 *ov8856)

{

	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);

	int ret;

	u32 val;



	ret = ov8856_read_reg(ov8856, OV8856_REG_CHIP_ID,

			      OV8856_REG_VALUE_24BIT, &val);

	if (ret)

		return ret;



	if (val != OV8856_CHIP_ID) {

		dev_err(&client->dev, "chip id mismatch: %x!=%x",

			OV8856_CHIP_ID, val);

		return -ENXIO;

	}



	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,

			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STREAMING);

	if (ret)

		return ret;



	ret = ov8856_write_reg(ov8856, OV8856_OTP_MODE_CTRL,

			       OV8856_REG_VALUE_08BIT, OV8856_OTP_MODE_AUTO);

	if (ret) {

		dev_err(&client->dev, "failed to set otp mode");

		return ret;

	}



	ret = ov8856_write_reg(ov8856, OV8856_OTP_LOAD_CTRL,

			       OV8856_REG_VALUE_08BIT,

			       OV8856_OTP_LOAD_CTRL_ENABLE);

	if (ret) {

		dev_err(&client->dev, "failed to enable load control");

		return ret;

	}



	ret = ov8856_read_reg(ov8856, OV8856_MODULE_REVISION,

			      OV8856_REG_VALUE_08BIT, &val);

	if (ret) {

		dev_err(&client->dev, "failed to read module revision");

		return ret;

	}



	dev_info(&client->dev, "OV8856 revision %x (%s) at address 0x%02x\n",

		 val,

		 val == OV8856_2A_MODULE ? "2A" :

		 val == OV8856_1B_MODULE ? "1B" : "unknown revision",

		 client->addr);



	ret = ov8856_write_reg(ov8856, OV8856_REG_MODE_SELECT,

			       OV8856_REG_VALUE_08BIT, OV8856_MODE_STANDBY);

	if (ret) {

		dev_err(&client->dev, "failed to exit streaming mode");

		return ret;

	}



	return 0;

}



static int ov8856_get_hwcfg(struct ov8856 *ov8856, struct device *dev)

{
@@ -2458,6 +2471,7 @@ static int ov8856_probe(struct i2c_client *client) 
{

	struct ov8856 *ov8856;

	int ret;

	bool full_power;



	ov8856 = devm_kzalloc(&client->dev, sizeof(*ov8856), GFP_KERNEL);

	if (!ov8856)
@@ -2472,6 +2486,8 @@ static int ov8856_probe(struct i2c_client *client) 


	v4l2_i2c_subdev_init(&ov8856->sd, client, &ov8856_subdev_ops);



	full_power = acpi_dev_state_d0(&client->dev);

	if (full_power) {

		ret = __ov8856_power_on(ov8856);

		if (ret) {

			dev_err(&client->dev, "failed to power on\n");
@@ -2483,6 +2499,7 @@ static int ov8856_probe(struct i2c_client *client) 
			dev_err(&client->dev, "failed to find sensor: %d", ret);

			goto probe_power_off;

		}

	}



	mutex_init(&ov8856->mutex);

	ov8856->cur_mode = &ov8856->priv_lane->supported_modes[0];
@@ -2511,10 +2528,8 @@ static int ov8856_probe(struct i2c_client *client) 
		goto probe_error_media_entity_cleanup;

	}



	/*

	 * Device is already turned on by i2c-core with ACPI domain PM.

	 * Enable runtime PM and turn off the device.

	 */

	/* 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);
@@ -2562,6 +2577,7 @@ static struct i2c_driver ov8856_i2c_driver = { 
	},

	.probe_new = ov8856_probe,

	.remove = ov8856_remove,

	.flags = I2C_DRV_ACPI_WAIVE_D0_PROBE,

};



module_i2c_driver(ov8856_i2c_driver);