Commit e21b5b1f authored by Mårten Lindahl's avatar Mårten Lindahl Committed by Jonathan Cameron
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iio: light: vcnl4000: Preserve conf bits when toggle power 



As the vcnl4040 and vcnl4200 chip uses runtime power management for
turning the ambient light and proximity sensors on/off, it overwrites
the entire register each time. In ALS_CONF register bit fields ALS_IT,
ALS_PERS, ALS_INT_EN are overwritten. In PS_CONF1 register bit fields
PS_DUTY, PS_PERS, PS_IT, PS_HD, and PS_INT are overwritten.

Add functions for preserving the affected bit fields when changing power
state.

Signed-off-by: default avatarMårten Lindahl <marten.lindahl@axis.com>
Link: https://lore.kernel.org/r/20220926091900.1724105-2-marten.lindahl@axis.com


Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 3f4033a8

drivers/iio/light/vcnl4000.c

+51 −3
Original line number Diff line number Diff line
@@ -74,6 +74,9 @@ 
#define VCNL4000_PROX_EN	BIT(1) /* start proximity measurement */

#define VCNL4000_SELF_TIMED_EN	BIT(0) /* start self-timed measurement */



#define VCNL4040_ALS_CONF_ALS_SHUTDOWN	BIT(0)

#define VCNL4040_PS_CONF1_PS_SHUTDOWN	BIT(0)



/* Bit masks for interrupt registers. */

#define VCNL4010_INT_THR_SEL	BIT(0) /* Select threshold interrupt source */

#define VCNL4010_INT_THR_EN	BIT(1) /* Threshold interrupt type */
@@ -188,16 +191,61 @@ static int vcnl4000_init(struct vcnl4000_data *data) 
	return data->chip_spec->set_power_state(data, true);

};



static ssize_t vcnl4000_write_als_enable(struct vcnl4000_data *data, bool en)

{

	int ret;



	mutex_lock(&data->vcnl4000_lock);



	ret = i2c_smbus_read_word_data(data->client, VCNL4200_AL_CONF);

	if (ret < 0)

		goto out;



	if (en)

		ret &= ~VCNL4040_ALS_CONF_ALS_SHUTDOWN;

	else

		ret |= VCNL4040_ALS_CONF_ALS_SHUTDOWN;



	ret = i2c_smbus_write_word_data(data->client, VCNL4200_AL_CONF, ret);



out:

	mutex_unlock(&data->vcnl4000_lock);



	return ret;

}



static ssize_t vcnl4000_write_ps_enable(struct vcnl4000_data *data, bool en)

{

	int ret;



	mutex_lock(&data->vcnl4000_lock);



	ret = i2c_smbus_read_word_data(data->client, VCNL4200_PS_CONF1);

	if (ret < 0)

		goto out;



	if (en)

		ret &= ~VCNL4040_PS_CONF1_PS_SHUTDOWN;

	else

		ret |= VCNL4040_PS_CONF1_PS_SHUTDOWN;



	ret = i2c_smbus_write_word_data(data->client, VCNL4200_PS_CONF1, ret);



out:

	mutex_unlock(&data->vcnl4000_lock);



	return ret;

}



static int vcnl4200_set_power_state(struct vcnl4000_data *data, bool on)

{

	u16 val = on ? 0 /* power on */ : 1 /* shut down */;

	int ret;



	ret = i2c_smbus_write_word_data(data->client, VCNL4200_AL_CONF, val);

	ret = vcnl4000_write_als_enable(data, on);

	if (ret < 0)

		return ret;



	ret = i2c_smbus_write_word_data(data->client, VCNL4200_PS_CONF1, val);

	ret = vcnl4000_write_ps_enable(data, on);

	if (ret < 0)

		return ret;