diff options
| author |   Nicolin Chen <nicoleotsuka@gmail.com> | 2019-04-17 16:12:09 -0700 |
|---|---|---|
| committer |   Guenter Roeck <linux@roeck-us.net> | 2019-04-18 06:37:25 -0700 |
| commit | 521c0b6116ef60e4b96ba42dbf285b2ad69071d4 (patch) | |
| tree | 5531a43aec4f8fe58c96764af8761bcdd84096ec /drivers/hwmon | |
| parent | docs: hwmon: Add an index file and rename docs to *.rst (diff) | |
| download | wireguard-linux-521c0b6116ef60e4b96ba42dbf285b2ad69071d4.tar.xz wireguard-linux-521c0b6116ef60e4b96ba42dbf285b2ad69071d4.zip | |
hwmon: (ina3221) Do not read-back to cache reg_config
Reading back the CONFIG register increases an extra I2C
transaction. This's not necessary and could be replaced
with a local variable caching the register settings.
So this patch replaces two readback regmap_read() calls
with a tmp variable.
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/ina3221.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/drivers/hwmon/ina3221.c b/drivers/hwmon/ina3221.c index 74d39d212931..62040aac653c 100644 --- a/drivers/hwmon/ina3221.c +++ b/drivers/hwmon/ina3221.c @@ -309,21 +309,22 @@ static int ina3221_write_chip(struct device *dev, u32 attr, long val) { struct ina3221_data *ina = dev_get_drvdata(dev); int ret, idx; + u32 tmp; switch (attr) { case hwmon_chip_samples: idx = find_closest(val, ina3221_avg_samples, ARRAY_SIZE(ina3221_avg_samples)); - ret = regmap_update_bits(ina->regmap, INA3221_CONFIG, - INA3221_CONFIG_AVG_MASK, - idx << INA3221_CONFIG_AVG_SHIFT); + tmp = (ina->reg_config & ~INA3221_CONFIG_AVG_MASK) | + (idx << INA3221_CONFIG_AVG_SHIFT); + ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp); if (ret) return ret; /* Update reg_config accordingly */ - return regmap_read(ina->regmap, INA3221_CONFIG, - &ina->reg_config); + ina->reg_config = tmp; + return 0; default: return -EOPNOTSUPP; } @@ -359,6 +360,7 @@ static int ina3221_write_enable(struct device *dev, int channel, bool enable) struct ina3221_data *ina = dev_get_drvdata(dev); u16 config, mask = INA3221_CONFIG_CHx_EN(channel); u16 config_old = ina->reg_config & mask; + u32 tmp; int ret; config = enable ? mask : 0; @@ -377,14 +379,13 @@ static int ina3221_write_enable(struct device *dev, int channel, bool enable) } /* Enable or disable the channel */ - ret = regmap_update_bits(ina->regmap, INA3221_CONFIG, mask, config); + tmp = (ina->reg_config & ~mask) | (config & mask); + ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp); if (ret) goto fail; /* Cache the latest config register value */ - ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config); - if (ret) - goto fail; + ina->reg_config = tmp; /* For disabling routine, decrease refcount or suspend() at last */ if (!enable) |