From e21b5b1f26694a4498ca11a15e09ccc0a72abb81 Mon Sep 17 00:00:00 2001 From: =?utf8?q?M=C3=A5rten=20Lindahl?= Date: Mon, 26 Sep 2022 11:18:59 +0200 Subject: [PATCH] iio: light: vcnl4000: Preserve conf bits when toggle power MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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: MÃ¥rten Lindahl Link: https://lore.kernel.org/r/20220926091900.1724105-2-marten.lindahl@axis.com Signed-off-by: Jonathan Cameron --- drivers/iio/light/vcnl4000.c | 54 +++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 51 insertions(+), 3 deletions(-) diff --git a/drivers/iio/light/vcnl4000.c b/drivers/iio/light/vcnl4000.c index f6c83ec..bc8c974c 100644 --- a/drivers/iio/light/vcnl4000.c +++ b/drivers/iio/light/vcnl4000.c @@ -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; -- 2.7.4