Re: [PATCH 1/2] iio: ina2xx: Fix whitespace and re-order code
From: Jonathan Cameron
Date: Sat Feb 13 2016 - 07:55:43 EST
On 12/02/16 18:34, Andrew F. Davis wrote:
> Group of probably overly rigorous whitespace and code cleanups.
> - Alphabetize includes
> - Assign to variables in the order they are defined
> - Alignment issues
> - Group alike statements together
> - Use helper macros
>
> Signed-off-by: Andrew F. Davis <afd@xxxxxx>
Definitely overzealous in some cases - but some good stuff in here
as well. Some of this just adds noise for no real gain. From the point
of view of bisection etc - we have to balance the possible cost of the
more minor cleanups against their benefits.
I'll run through and give my opinion on which ones are worthwhile etc.
Quite a few are marginal, but I feel fairly strongly against one of the
changes in alignment of the \ in the large macro.
Jonathan
> ---
> drivers/iio/adc/ina2xx-adc.c | 164 +++++++++++++++++++++----------------------
> 1 file changed, 80 insertions(+), 84 deletions(-)
>
> diff --git a/drivers/iio/adc/ina2xx-adc.c b/drivers/iio/adc/ina2xx-adc.c
> index d803e50..61e8ae9 100644
> --- a/drivers/iio/adc/ina2xx-adc.c
> +++ b/drivers/iio/adc/ina2xx-adc.c
> @@ -19,17 +19,18 @@
> *
> * Configurable 7-bit I2C slave address from 0x40 to 0x4F
> */
> -#include <linux/module.h>
> -#include <linux/kthread.h>
> +
> #include <linux/delay.h>
> +#include <linux/i2c.h>
> #include <linux/iio/kfifo_buf.h>
> #include <linux/iio/sysfs.h>
> -#include <linux/i2c.h>
> +#include <linux/kthread.h>
> +#include <linux/module.h>
> #include <linux/regmap.h>
> -#include <linux/platform_data/ina2xx.h>
> -
> #include <linux/util_macros.h>
There is sometimes some logical grouping going on in the way the author
decides to put the headers in, here it's not that well defined that
I can see. However, there is no real benefit in alphabetical order either
though clearly some other projects disagree and do mandate this...
>
> +#include <linux/platform_data/ina2xx.h>
> +
> /* INA2XX registers definition */
> #define INA2XX_CONFIG 0x00
> #define INA2XX_SHUNT_VOLTAGE 0x01 /* readonly */
> @@ -38,7 +39,7 @@
> #define INA2XX_CURRENT 0x04 /* readonly */
> #define INA2XX_CALIBRATION 0x05
>
> -#define INA226_ALERT_MASK 0x06
> +#define INA226_ALERT_MASK GENMASK(2, 1)
> #define INA266_CVRF BIT(3)
>
> #define INA2XX_MAX_REGISTERS 8
> @@ -113,7 +114,7 @@ struct ina2xx_chip_info {
> struct mutex state_lock;
> unsigned int shunt_resistor;
> int avg;
> - s64 prev_ns; /* track buffer capture time, check for underruns*/
> + s64 prev_ns; /* track buffer capture time, check for underruns*/
Fair enough, though a space before the */ would be nice!
> int int_time_vbus; /* Bus voltage integration time uS */
> int int_time_vshunt; /* Shunt voltage integration time uS */
> bool allow_async_readout;
> @@ -121,21 +122,21 @@ struct ina2xx_chip_info {
>
> static const struct ina2xx_config ina2xx_config[] = {
> [ina219] = {
I'd have left this indenting alone. It's more of a matter of taste
than any hard and fast rule. I'd do indenting myself the way
you have, but it's not worth the noise to change it.
> - .config_default = INA219_CONFIG_DEFAULT,
> - .calibration_factor = 40960000,
> - .shunt_div = 100,
> - .bus_voltage_shift = 3,
> - .bus_voltage_lsb = 4000,
> - .power_lsb = 20000,
> - },
> + .config_default = INA219_CONFIG_DEFAULT,
> + .calibration_factor = 40960000,
> + .shunt_div = 100,
> + .bus_voltage_shift = 3,
> + .bus_voltage_lsb = 4000,
> + .power_lsb = 20000,
> + },
> [ina226] = {
> - .config_default = INA226_CONFIG_DEFAULT,
> - .calibration_factor = 5120000,
> - .shunt_div = 400,
> - .bus_voltage_shift = 0,
> - .bus_voltage_lsb = 1250,
> - .power_lsb = 25000,
> - },
> + .config_default = INA226_CONFIG_DEFAULT,
> + .calibration_factor = 5120000,
> + .shunt_div = 400,
> + .bus_voltage_shift = 0,
> + .bus_voltage_lsb = 1250,
> + .power_lsb = 25000,
> + },
> };
>
> static int ina2xx_read_raw(struct iio_dev *indio_dev,
> @@ -149,7 +150,7 @@ static int ina2xx_read_raw(struct iio_dev *indio_dev,
> switch (mask) {
> case IIO_CHAN_INFO_RAW:
> ret = regmap_read(chip->regmap, chan->address, ®val);
> - if (ret < 0)
> + if (ret)
> return ret;
These are good to clean up.
>
> if (is_signed_reg(chan->address))
> @@ -251,7 +252,7 @@ static int ina226_set_int_time_vbus(struct ina2xx_chip_info *chip,
> return -EINVAL;
>
> bits = find_closest(val_us, ina226_conv_time_tab,
> - ARRAY_SIZE(ina226_conv_time_tab));
> + ARRAY_SIZE(ina226_conv_time_tab));
Good to get these nicely aligned as well.
>
> chip->int_time_vbus = ina226_conv_time_tab[bits];
>
> @@ -270,7 +271,7 @@ static int ina226_set_int_time_vshunt(struct ina2xx_chip_info *chip,
> return -EINVAL;
>
> bits = find_closest(val_us, ina226_conv_time_tab,
> - ARRAY_SIZE(ina226_conv_time_tab));
> + ARRAY_SIZE(ina226_conv_time_tab));
>
> chip->int_time_vshunt = ina226_conv_time_tab[bits];
>
> @@ -285,8 +286,8 @@ static int ina2xx_write_raw(struct iio_dev *indio_dev,
> int val, int val2, long mask)
> {
> struct ina2xx_chip_info *chip = iio_priv(indio_dev);
> - int ret;
> unsigned int config, tmp;
> + int ret;
Definitely in the doesn't matter category, but if you really want to this
one is fine.
>
> if (iio_buffer_enabled(indio_dev))
> return -EBUSY;
> @@ -294,8 +295,8 @@ static int ina2xx_write_raw(struct iio_dev *indio_dev,
> mutex_lock(&chip->state_lock);
>
> ret = regmap_read(chip->regmap, INA2XX_CONFIG, &config);
> - if (ret < 0)
> - goto _err;
> + if (ret)
> + goto err;
Good.
>
> tmp = config;
>
> @@ -310,19 +311,19 @@ static int ina2xx_write_raw(struct iio_dev *indio_dev,
> else
> ret = ina226_set_int_time_vbus(chip, val2, &tmp);
> break;
> +
Maybe a slight gain in readability so fair enough.
> default:
> ret = -EINVAL;
> }
>
> if (!ret && (tmp != config))
> ret = regmap_write(chip->regmap, INA2XX_CONFIG, tmp);
> -_err:
> +err:
Fine.
> mutex_unlock(&chip->state_lock);
>
> return ret;
> }
>
> -
> static ssize_t ina2xx_allow_async_readout_show(struct device *dev,
> struct device_attribute *attr,
> char *buf)
> @@ -355,6 +356,7 @@ static int set_shunt_resistor(struct ina2xx_chip_info *chip, unsigned int val)
> return -EINVAL;
>
> chip->shunt_resistor = val;
> +
good.
> return 0;
> }
>
> @@ -408,21 +410,21 @@ static ssize_t ina2xx_shunt_resistor_store(struct device *dev,
> * Sampling Freq is a consequence of the integration times of
> * the Voltage channels.
> */
> -#define INA2XX_CHAN_VOLTAGE(_index, _address) { \
> - .type = IIO_VOLTAGE, \
> - .address = (_address), \
> - .indexed = 1, \
> - .channel = (_index), \
> - .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> - BIT(IIO_CHAN_INFO_SCALE) | \
> - BIT(IIO_CHAN_INFO_INT_TIME), \
> - .scan_index = (_index), \
> - .scan_type = { \
> - .sign = 'u', \
> - .realbits = 16, \
> - .storagebits = 16, \
> - .endianness = IIO_LE, \
> - } \
This one I disagree with. It too often leads to noise when we end up with
an element with a line and have to change the spacing before the \s.
Much less churn occurs with teh version as original defined.
As someone who handles a fair number of patch reviews I feel pretty strongly
about anything that leads to more churn.
> +#define INA2XX_CHAN_VOLTAGE(_index, _address) { \
> + .type = IIO_VOLTAGE, \
> + .address = (_address), \
> + .indexed = 1, \
> + .channel = (_index), \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
> + BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_INT_TIME), \
> + .scan_index = (_index), \
> + .scan_type = { \
> + .sign = 'u', \
> + .realbits = 16, \
> + .storagebits = 16, \
> + .endianness = IIO_LE, \
> + } \
> }
>
> static const struct iio_chan_spec ina2xx_channels[] = {
> @@ -500,7 +502,7 @@ static int ina2xx_work_buffer(struct iio_dev *indio_dev)
>
> static int ina2xx_capture_thread(void *data)
> {
> - struct iio_dev *indio_dev = (struct iio_dev *)data;
> + struct iio_dev *indio_dev = data;
good.
> struct ina2xx_chip_info *chip = iio_priv(indio_dev);
> unsigned int sampling_us = SAMPLING_PERIOD(chip);
> int buffer_us;
> @@ -575,8 +577,7 @@ static int ina2xx_debug_reg(struct iio_dev *indio_dev,
> }
>
> /* Possible integration times for vshunt and vbus */
> -static IIO_CONST_ATTR_INT_TIME_AVAIL \
> - ("0.000140 0.000204 0.000332 0.000588 0.001100 0.002116 0.004156 0.008244");
> +static IIO_CONST_ATTR_INT_TIME_AVAIL("0.000140 0.000204 0.000332 0.000588 0.001100 0.002116 0.004156 0.008244");
>
> static IIO_DEVICE_ATTR(in_allow_async_readout, S_IRUGO | S_IWUSR,
> ina2xx_allow_async_readout_show,
> @@ -598,21 +599,23 @@ static const struct attribute_group ina2xx_attribute_group = {
> };
>
> static const struct iio_info ina2xx_info = {
> - .debugfs_reg_access = &ina2xx_debug_reg,
> - .read_raw = &ina2xx_read_raw,
> - .write_raw = &ina2xx_write_raw,
> - .attrs = &ina2xx_attribute_group,
> .driver_module = THIS_MODULE,
> + .attrs = &ina2xx_attribute_group,
> + .read_raw = ina2xx_read_raw,
> + .write_raw = ina2xx_write_raw,
> + .debugfs_reg_access = ina2xx_debug_reg,
sensible change.
> };
>
> /* Initialize the configuration and calibration registers. */
> static int ina2xx_init(struct ina2xx_chip_info *chip, unsigned int config)
> {
> u16 regval;
> - int ret = regmap_write(chip->regmap, INA2XX_CONFIG, config);
> + int ret;
This form is considered acceptable in kernel code - but perhaps yours is
a tiny bit more readable so if you want to keep this one.
>
> - if (ret < 0)
> + ret = regmap_write(chip->regmap, INA2XX_CONFIG, config);
> + if (ret)
> return ret;
good
> +
> /*
> * Set current LSB to 1mA, shunt is in uOhms
> * (equation 13 in datasheet). We hardcode a Current_LSB
> @@ -621,7 +624,7 @@ static int ina2xx_init(struct ina2xx_chip_info *chip, unsigned int config)
> * to the user for now.
> */
> regval = DIV_ROUND_CLOSEST(chip->config->calibration_factor,
> - chip->shunt_resistor);
> + chip->shunt_resistor);
good
>
> return regmap_write(chip->regmap, INA2XX_CALIBRATION, regval);
> }
> @@ -632,8 +635,8 @@ static int ina2xx_probe(struct i2c_client *client,
> struct ina2xx_chip_info *chip;
> struct iio_dev *indio_dev;
> struct iio_buffer *buffer;
> - int ret;
> unsigned int val;
> + int ret;
Again, don't care on this one.
>
> indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
> if (!indio_dev)
> @@ -641,8 +644,19 @@ static int ina2xx_probe(struct i2c_client *client,
>
> chip = iio_priv(indio_dev);
>
All this reordering needs a detailed justification. It adds a lot of churn
for limited benefit. I prefer the ordering you end up with, but is it
worth the noise? Not to my mind.
> + /* This is only used for device removal purposes. */
> + i2c_set_clientdata(client, indio_dev);
> +
> + chip->regmap = devm_regmap_init_i2c(client, &ina2xx_regmap_config);
> + if (IS_ERR(chip->regmap)) {
> + dev_err(&client->dev, "failed to allocate register map\n");
> + return PTR_ERR(chip->regmap);
> + }
> +
> chip->config = &ina2xx_config[id->driver_data];
>
> + mutex_init(&chip->state_lock);
> +
> if (of_property_read_u32(client->dev.of_node,
> "shunt-resistor", &val) < 0) {
> struct ina2xx_platform_data *pdata =
> @@ -658,25 +672,6 @@ static int ina2xx_probe(struct i2c_client *client,
> if (ret)
> return ret;
>
> - mutex_init(&chip->state_lock);
> -
> - /* This is only used for device removal purposes. */
> - i2c_set_clientdata(client, indio_dev);
> -
> - indio_dev->name = id->name;
> - indio_dev->channels = ina2xx_channels;
> - indio_dev->num_channels = ARRAY_SIZE(ina2xx_channels);
> -
> - indio_dev->dev.parent = &client->dev;
> - indio_dev->info = &ina2xx_info;
> - indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
> -
> - chip->regmap = devm_regmap_init_i2c(client, &ina2xx_regmap_config);
> - if (IS_ERR(chip->regmap)) {
> - dev_err(&client->dev, "failed to allocate register map\n");
> - return PTR_ERR(chip->regmap);
> - }
> -
> /* Patch the current config register with default. */
> val = chip->config->config_default;
>
> @@ -687,24 +682,28 @@ static int ina2xx_probe(struct i2c_client *client,
> }
>
> ret = ina2xx_init(chip, val);
> - if (ret < 0) {
> - dev_err(&client->dev, "error configuring the device: %d\n",
> - ret);
> - return -ENODEV;
> + if (ret) {
This change is good however.
> + dev_err(&client->dev, "error configuring the device\n");
Dropping the return value might be 'cleaner' in some sense, but I don't think
it's worth making the change.
> + return ret;
> }
>
> + indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_SOFTWARE;
> + indio_dev->dev.parent = &client->dev;
> + indio_dev->channels = ina2xx_channels;
> + indio_dev->num_channels = ARRAY_SIZE(ina2xx_channels);
> + indio_dev->name = id->name;
> + indio_dev->info = &ina2xx_info;
> + indio_dev->setup_ops = &ina2xx_setup_ops;
> +
> buffer = devm_iio_kfifo_allocate(&indio_dev->dev);
> if (!buffer)
> return -ENOMEM;
>
> - indio_dev->setup_ops = &ina2xx_setup_ops;
> -
> iio_device_attach_buffer(indio_dev, buffer);
>
> return iio_device_register(indio_dev);
> }
>
> -
> static int ina2xx_remove(struct i2c_client *client)
> {
> struct iio_dev *indio_dev = i2c_get_clientdata(client);
> @@ -717,7 +716,6 @@ static int ina2xx_remove(struct i2c_client *client)
> INA2XX_MODE_MASK, 0);
> }
>
> -
good.
> static const struct i2c_device_id ina2xx_id[] = {
> {"ina219", ina219},
> {"ina220", ina219},
> @@ -726,7 +724,6 @@ static const struct i2c_device_id ina2xx_id[] = {
> {"ina231", ina226},
> {}
> };
> -
good
> MODULE_DEVICE_TABLE(i2c, ina2xx_id);
>
> static struct i2c_driver ina2xx_driver = {
> @@ -737,7 +734,6 @@ static struct i2c_driver ina2xx_driver = {
> .remove = ina2xx_remove,
> .id_table = ina2xx_id,
> };
> -
good as well.
> module_i2c_driver(ina2xx_driver);
>
> MODULE_AUTHOR("Marc Titinger <marc.titinger@xxxxxxxxxxxx>");
>