Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 521c0b61 authored by Nicolin Chen's avatar Nicolin Chen Committed by Guenter Roeck
Browse files

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: default avatarNicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 7ebd8b66

drivers/hwmon/ina3221.c

+10 −9
Original line number Diff line number Diff line
@@ -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)