Re: [PATCH v3 3/8] staging:iio:ade7854: Rework I2C write function

From: Jonathan Cameron
Date: Sat Mar 24 2018 - 09:24:52 EST


On Fri, 23 Mar 2018 11:26:06 -0300
Rodrigo Siqueira <rodrigosiqueiramelo@xxxxxxxxx> wrote:

> The write operation using I2C has many code duplications and four
> different interfaces per data size. This patch introduces a single
> function that centralizes the main tasks.
>
> The central function inserted by this patch can easily replace all the
> four functions related to the data size. However, this patch does not
> remove any code signature for keeping the meter module work and make
> easier to review this patch.
>
> Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@xxxxxxxxx>
Applied.

Thanks,

Jonathan

> ---
> Changes in v3:
> - Remove the use of defines that not improve the readability
> - Replace variable name "bytes" for "bits"
>
> drivers/staging/iio/meter/ade7854-i2c.c | 96 ++++++++++++++++-----------------
> 1 file changed, 46 insertions(+), 50 deletions(-)
>
> diff --git a/drivers/staging/iio/meter/ade7854-i2c.c b/drivers/staging/iio/meter/ade7854-i2c.c
> index 37c957482493..c9f46d26b752 100644
> --- a/drivers/staging/iio/meter/ade7854-i2c.c
> +++ b/drivers/staging/iio/meter/ade7854-i2c.c
> @@ -15,86 +15,82 @@
> #include <linux/iio/iio.h>
> #include "ade7854.h"
>
> -static int ade7854_i2c_write_reg_8(struct device *dev,
> - u16 reg_address,
> - u8 val)
> +static int ade7854_i2c_write_reg(struct device *dev,
> + u16 reg_address,
> + u32 val,
> + int bits)
> {
> int ret;
> + int count;
> struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> struct ade7854_state *st = iio_priv(indio_dev);
>
> mutex_lock(&st->buf_lock);
> st->tx[0] = (reg_address >> 8) & 0xFF;
> st->tx[1] = reg_address & 0xFF;
> - st->tx[2] = val;
>
> - ret = i2c_master_send(st->i2c, st->tx, 3);
> + switch (bits) {
> + case 8:
> + st->tx[2] = val & 0xFF;
> + count = 3;
> + break;
> + case 16:
> + st->tx[2] = (val >> 8) & 0xFF;
> + st->tx[3] = val & 0xFF;
> + count = 4;
> + break;
> + case 24:
> + st->tx[2] = (val >> 16) & 0xFF;
> + st->tx[3] = (val >> 8) & 0xFF;
> + st->tx[4] = val & 0xFF;
> + count = 5;
> + break;
> + case 32:
> + st->tx[2] = (val >> 24) & 0xFF;
> + st->tx[3] = (val >> 16) & 0xFF;
> + st->tx[4] = (val >> 8) & 0xFF;
> + st->tx[5] = val & 0xFF;
> + count = 6;
> + break;
> + default:
> + ret = -EINVAL;
> + goto unlock;
> + }
> +
> + ret = i2c_master_send(st->i2c, st->tx, count);
> +
> +unlock:
> mutex_unlock(&st->buf_lock);
>
> return ret < 0 ? ret : 0;
> }
>
> +static int ade7854_i2c_write_reg_8(struct device *dev,
> + u16 reg_address,
> + u8 val)
> +{
> + return ade7854_i2c_write_reg(dev, reg_address, val, 8);
> +}
> +
> static int ade7854_i2c_write_reg_16(struct device *dev,
> u16 reg_address,
> u16 val)
> {
> - int ret;
> - struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> - struct ade7854_state *st = iio_priv(indio_dev);
> -
> - mutex_lock(&st->buf_lock);
> - st->tx[0] = (reg_address >> 8) & 0xFF;
> - st->tx[1] = reg_address & 0xFF;
> - st->tx[2] = (val >> 8) & 0xFF;
> - st->tx[3] = val & 0xFF;
> -
> - ret = i2c_master_send(st->i2c, st->tx, 4);
> - mutex_unlock(&st->buf_lock);
> -
> - return ret < 0 ? ret : 0;
> + return ade7854_i2c_write_reg(dev, reg_address, val, 16);
> }
>
> static int ade7854_i2c_write_reg_24(struct device *dev,
> u16 reg_address,
> u32 val)
> {
> - int ret;
> - struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> - struct ade7854_state *st = iio_priv(indio_dev);
> -
> - mutex_lock(&st->buf_lock);
> - st->tx[0] = (reg_address >> 8) & 0xFF;
> - st->tx[1] = reg_address & 0xFF;
> - st->tx[2] = (val >> 16) & 0xFF;
> - st->tx[3] = (val >> 8) & 0xFF;
> - st->tx[4] = val & 0xFF;
> -
> - ret = i2c_master_send(st->i2c, st->tx, 5);
> - mutex_unlock(&st->buf_lock);
> -
> - return ret < 0 ? ret : 0;
> + return ade7854_i2c_write_reg(dev, reg_address, val, 24);
> }
>
> static int ade7854_i2c_write_reg_32(struct device *dev,
> u16 reg_address,
> u32 val)
> {
> - int ret;
> - struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> - struct ade7854_state *st = iio_priv(indio_dev);
> -
> - mutex_lock(&st->buf_lock);
> - st->tx[0] = (reg_address >> 8) & 0xFF;
> - st->tx[1] = reg_address & 0xFF;
> - st->tx[2] = (val >> 24) & 0xFF;
> - st->tx[3] = (val >> 16) & 0xFF;
> - st->tx[4] = (val >> 8) & 0xFF;
> - st->tx[5] = val & 0xFF;
> -
> - ret = i2c_master_send(st->i2c, st->tx, 6);
> - mutex_unlock(&st->buf_lock);
> -
> - return ret < 0 ? ret : 0;
> + return ade7854_i2c_write_reg(dev, reg_address, val, 32);
> }
>
> static int ade7854_i2c_read_reg_8(struct device *dev,