Replace two divisions with a subtraction+shift for a small code size
improvement and less brackets.
Signed-off-by: Michał Mirosław <[email protected]>
---
drivers/power/supply/ltc2941-battery-gauge.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/power/supply/ltc2941-battery-gauge.c b/drivers/power/supply/ltc2941-battery-gauge.c
index 09f3e78af4e0..c0cbf4cd59ee 100644
--- a/drivers/power/supply/ltc2941-battery-gauge.c
+++ b/drivers/power/supply/ltc2941-battery-gauge.c
@@ -490,13 +490,13 @@ static int ltc294x_i2c_probe(struct i2c_client *client,
if (info->id == LTC2943_ID) {
if (prescaler_exp > LTC2943_MAX_PRESCALER_EXP)
prescaler_exp = LTC2943_MAX_PRESCALER_EXP;
- info->Qlsb = ((340 * 50000) / r_sense) /
- (4096 / (1 << (2*prescaler_exp)));
+ info->Qlsb = ((340 * 50000) / r_sense) >>
+ (12 - 2*prescaler_exp);
} else {
if (prescaler_exp > LTC2941_MAX_PRESCALER_EXP)
prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
- info->Qlsb = ((85 * 50000) / r_sense) /
- (128 / (1 << prescaler_exp));
+ info->Qlsb = ((85 * 50000) / r_sense) >>
+ (7 - prescaler_exp);
}
/* Read status register to check for LTC2942 */
--
2.30.2
Replace dev_err() with dev_err_probe() in probe() and extend register
access failure messages. dev_err()s in _reset() are removed as they
are redundant: register access wrappers already log the error.
Signed-off-by: Michał Mirosław <[email protected]>
---
drivers/power/supply/ltc2941-battery-gauge.c | 53 ++++++++------------
1 file changed, 20 insertions(+), 33 deletions(-)
diff --git a/drivers/power/supply/ltc2941-battery-gauge.c b/drivers/power/supply/ltc2941-battery-gauge.c
index c0cbf4cd59ee..657305214d68 100644
--- a/drivers/power/supply/ltc2941-battery-gauge.c
+++ b/drivers/power/supply/ltc2941-battery-gauge.c
@@ -112,7 +112,8 @@ static int ltc294x_read_regs(struct i2c_client *client,
ret = i2c_transfer(client->adapter, &msgs[0], 2);
if (ret < 0) {
- dev_err(&client->dev, "ltc2941 read_reg failed!\n");
+ dev_err(&client->dev, "ltc2941 read_reg(0x%x[%d]) failed: %pe\n",
+ reg, num_regs, ERR_PTR(ret));
return ret;
}
@@ -130,7 +131,8 @@ static int ltc294x_write_regs(struct i2c_client *client,
ret = i2c_smbus_write_i2c_block_data(client, reg_start, num_regs, buf);
if (ret < 0) {
- dev_err(&client->dev, "ltc2941 write_reg failed!\n");
+ dev_err(&client->dev, "ltc2941 write_reg(0x%x[%d]) failed: %pe\n",
+ reg, num_regs, ERR_PTR(ret));
return ret;
}
@@ -148,11 +150,8 @@ static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
/* Read status and control registers */
ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
- if (ret < 0) {
- dev_err(&info->client->dev,
- "Could not read registers from device\n");
- goto error_exit;
- }
+ if (ret < 0)
+ return ret;
control = LTC294X_REG_CONTROL_PRESCALER_SET(prescaler_exp) |
LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED;
@@ -172,17 +171,11 @@ static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
if (value != control) {
ret = ltc294x_write_regs(info->client,
LTC294X_REG_CONTROL, &control, 1);
- if (ret < 0) {
- dev_err(&info->client->dev,
- "Could not write register\n");
- goto error_exit;
- }
+ if (ret < 0)
+ return ret;
}
return 0;
-
-error_exit:
- return ret;
}
static int ltc294x_read_charge_register(const struct ltc294x_info *info,
@@ -472,11 +465,9 @@ static int ltc294x_i2c_probe(struct i2c_client *client,
/* r_sense can be negative, when sense+ is connected to the battery
* instead of the sense-. This results in reversed measurements. */
ret = of_property_read_u32(np, "lltc,resistor-sense", &r_sense);
- if (ret < 0) {
- dev_err(&client->dev,
+ if (ret < 0)
+ return dev_err_probe(&client->dev, ret,
"Could not find lltc,resistor-sense in devicetree\n");
- return ret;
- }
info->r_sense = r_sense;
ret = of_property_read_u32(np, "lltc,prescaler-exponent",
@@ -502,11 +493,9 @@ static int ltc294x_i2c_probe(struct i2c_client *client,
/* Read status register to check for LTC2942 */
if (info->id == LTC2941_ID || info->id == LTC2942_ID) {
ret = ltc294x_read_regs(client, LTC294X_REG_STATUS, &status, 1);
- if (ret < 0) {
- dev_err(&client->dev,
+ if (ret < 0)
+ return dev_err_probe(&client->dev, ret,
"Could not read status register\n");
- return ret;
- }
if (status & LTC2941_REG_STATUS_CHIP_ID)
info->id = LTC2941_ID;
else
@@ -545,19 +534,17 @@ static int ltc294x_i2c_probe(struct i2c_client *client,
return ret;
ret = ltc294x_reset(info, prescaler_exp);
- if (ret < 0) {
- dev_err(&client->dev, "Communication with chip failed\n");
- return ret;
- }
+ if (ret < 0)
+ return dev_err_probe(&client->dev, ret,
+ "Communication with chip failed\n");
info->supply = devm_power_supply_register(&client->dev,
&info->supply_desc, &psy_cfg);
- if (IS_ERR(info->supply)) {
- dev_err(&client->dev, "failed to register ltc2941\n");
- return PTR_ERR(info->supply);
- } else {
- schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
- }
+ if (IS_ERR(info->supply))
+ return dev_err_probe(&client->dev, PTR_ERR(info->supply),
+ "failed to register ltc2941\n");
+
+ schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
return 0;
}
--
2.30.2
Hi,
On Tue, Jan 11, 2022 at 03:32:40AM +0100, Michał Mirosław wrote:
> Replace two divisions with a subtraction+shift for a small code size
> improvement and less brackets.
>
> Signed-off-by: Michał Mirosław <[email protected]>
> ---
Thanks, queued.
-- Sebastian
> drivers/power/supply/ltc2941-battery-gauge.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/power/supply/ltc2941-battery-gauge.c b/drivers/power/supply/ltc2941-battery-gauge.c
> index 09f3e78af4e0..c0cbf4cd59ee 100644
> --- a/drivers/power/supply/ltc2941-battery-gauge.c
> +++ b/drivers/power/supply/ltc2941-battery-gauge.c
> @@ -490,13 +490,13 @@ static int ltc294x_i2c_probe(struct i2c_client *client,
> if (info->id == LTC2943_ID) {
> if (prescaler_exp > LTC2943_MAX_PRESCALER_EXP)
> prescaler_exp = LTC2943_MAX_PRESCALER_EXP;
> - info->Qlsb = ((340 * 50000) / r_sense) /
> - (4096 / (1 << (2*prescaler_exp)));
> + info->Qlsb = ((340 * 50000) / r_sense) >>
> + (12 - 2*prescaler_exp);
> } else {
> if (prescaler_exp > LTC2941_MAX_PRESCALER_EXP)
> prescaler_exp = LTC2941_MAX_PRESCALER_EXP;
> - info->Qlsb = ((85 * 50000) / r_sense) /
> - (128 / (1 << prescaler_exp));
> + info->Qlsb = ((85 * 50000) / r_sense) >>
> + (7 - prescaler_exp);
> }
>
> /* Read status register to check for LTC2942 */
> --
> 2.30.2
>
Hi,
On Tue, Jan 11, 2022 at 03:32:41AM +0100, Michał Mirosław wrote:
> Replace dev_err() with dev_err_probe() in probe() and extend register
> access failure messages. dev_err()s in _reset() are removed as they
> are redundant: register access wrappers already log the error.
>
> Signed-off-by: Michał Mirosław <[email protected]>
> ---
Thanks, queued.
-- Sebastian
> drivers/power/supply/ltc2941-battery-gauge.c | 53 ++++++++------------
> 1 file changed, 20 insertions(+), 33 deletions(-)
>
> diff --git a/drivers/power/supply/ltc2941-battery-gauge.c b/drivers/power/supply/ltc2941-battery-gauge.c
> index c0cbf4cd59ee..657305214d68 100644
> --- a/drivers/power/supply/ltc2941-battery-gauge.c
> +++ b/drivers/power/supply/ltc2941-battery-gauge.c
> @@ -112,7 +112,8 @@ static int ltc294x_read_regs(struct i2c_client *client,
>
> ret = i2c_transfer(client->adapter, &msgs[0], 2);
> if (ret < 0) {
> - dev_err(&client->dev, "ltc2941 read_reg failed!\n");
> + dev_err(&client->dev, "ltc2941 read_reg(0x%x[%d]) failed: %pe\n",
> + reg, num_regs, ERR_PTR(ret));
> return ret;
> }
>
> @@ -130,7 +131,8 @@ static int ltc294x_write_regs(struct i2c_client *client,
>
> ret = i2c_smbus_write_i2c_block_data(client, reg_start, num_regs, buf);
> if (ret < 0) {
> - dev_err(&client->dev, "ltc2941 write_reg failed!\n");
> + dev_err(&client->dev, "ltc2941 write_reg(0x%x[%d]) failed: %pe\n",
> + reg, num_regs, ERR_PTR(ret));
> return ret;
> }
>
> @@ -148,11 +150,8 @@ static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
>
> /* Read status and control registers */
> ret = ltc294x_read_regs(info->client, LTC294X_REG_CONTROL, &value, 1);
> - if (ret < 0) {
> - dev_err(&info->client->dev,
> - "Could not read registers from device\n");
> - goto error_exit;
> - }
> + if (ret < 0)
> + return ret;
>
> control = LTC294X_REG_CONTROL_PRESCALER_SET(prescaler_exp) |
> LTC294X_REG_CONTROL_ALCC_CONFIG_DISABLED;
> @@ -172,17 +171,11 @@ static int ltc294x_reset(const struct ltc294x_info *info, int prescaler_exp)
> if (value != control) {
> ret = ltc294x_write_regs(info->client,
> LTC294X_REG_CONTROL, &control, 1);
> - if (ret < 0) {
> - dev_err(&info->client->dev,
> - "Could not write register\n");
> - goto error_exit;
> - }
> + if (ret < 0)
> + return ret;
> }
>
> return 0;
> -
> -error_exit:
> - return ret;
> }
>
> static int ltc294x_read_charge_register(const struct ltc294x_info *info,
> @@ -472,11 +465,9 @@ static int ltc294x_i2c_probe(struct i2c_client *client,
> /* r_sense can be negative, when sense+ is connected to the battery
> * instead of the sense-. This results in reversed measurements. */
> ret = of_property_read_u32(np, "lltc,resistor-sense", &r_sense);
> - if (ret < 0) {
> - dev_err(&client->dev,
> + if (ret < 0)
> + return dev_err_probe(&client->dev, ret,
> "Could not find lltc,resistor-sense in devicetree\n");
> - return ret;
> - }
> info->r_sense = r_sense;
>
> ret = of_property_read_u32(np, "lltc,prescaler-exponent",
> @@ -502,11 +493,9 @@ static int ltc294x_i2c_probe(struct i2c_client *client,
> /* Read status register to check for LTC2942 */
> if (info->id == LTC2941_ID || info->id == LTC2942_ID) {
> ret = ltc294x_read_regs(client, LTC294X_REG_STATUS, &status, 1);
> - if (ret < 0) {
> - dev_err(&client->dev,
> + if (ret < 0)
> + return dev_err_probe(&client->dev, ret,
> "Could not read status register\n");
> - return ret;
> - }
> if (status & LTC2941_REG_STATUS_CHIP_ID)
> info->id = LTC2941_ID;
> else
> @@ -545,19 +534,17 @@ static int ltc294x_i2c_probe(struct i2c_client *client,
> return ret;
>
> ret = ltc294x_reset(info, prescaler_exp);
> - if (ret < 0) {
> - dev_err(&client->dev, "Communication with chip failed\n");
> - return ret;
> - }
> + if (ret < 0)
> + return dev_err_probe(&client->dev, ret,
> + "Communication with chip failed\n");
>
> info->supply = devm_power_supply_register(&client->dev,
> &info->supply_desc, &psy_cfg);
> - if (IS_ERR(info->supply)) {
> - dev_err(&client->dev, "failed to register ltc2941\n");
> - return PTR_ERR(info->supply);
> - } else {
> - schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
> - }
> + if (IS_ERR(info->supply))
> + return dev_err_probe(&client->dev, PTR_ERR(info->supply),
> + "failed to register ltc2941\n");
> +
> + schedule_delayed_work(&info->work, LTC294X_WORK_DELAY * HZ);
>
> return 0;
> }
> --
> 2.30.2
>