Re: [PATCH v3 4/8] staging:iio:ade7854: Rework SPI write function

From: Jonathan Cameron
Date: Sat Mar 24 2018 - 09:25:52 EST


On Fri, 23 Mar 2018 11:26:25 -0300
Rodrigo Siqueira <rodrigosiqueiramelo@xxxxxxxxx> wrote:

> The write operation using SPI has a many code duplications (similar to
> I2C) and four different interfaces per data size. This patch introduces
> a single function that centralizes the main task related to SPI.
>
> 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-spi.c | 108 ++++++++++++--------------------
> 1 file changed, 41 insertions(+), 67 deletions(-)
>
> diff --git a/drivers/staging/iio/meter/ade7854-spi.c b/drivers/staging/iio/meter/ade7854-spi.c
> index 4419b8f06197..9c5c16c4d6e0 100644
> --- a/drivers/staging/iio/meter/ade7854-spi.c
> +++ b/drivers/staging/iio/meter/ade7854-spi.c
> @@ -15,9 +15,10 @@
> #include <linux/iio/iio.h>
> #include "ade7854.h"
>
> -static int ade7854_spi_write_reg_8(struct device *dev,
> - u16 reg_address,
> - u8 val)
> +static int ade7854_spi_write_reg(struct device *dev,
> + u16 reg_address,
> + u32 val,
> + int bits)
> {
> int ret;
> struct iio_dev *indio_dev = dev_to_iio_dev(dev);
> @@ -32,93 +33,66 @@ static int ade7854_spi_write_reg_8(struct device *dev,
> st->tx[0] = ADE7854_WRITE_REG;
> st->tx[1] = (reg_address >> 8) & 0xFF;
> st->tx[2] = reg_address & 0xFF;
> - st->tx[3] = val & 0xFF;
> + switch (bits) {
> + case 8:
> + st->tx[3] = val & 0xFF;
> + break;
> + case 16:
> + xfer.len = 5;
> + st->tx[3] = (val >> 8) & 0xFF;
> + st->tx[4] = val & 0xFF;
> + break;
> + case 24:
> + xfer.len = 6;
> + st->tx[3] = (val >> 16) & 0xFF;
> + st->tx[4] = (val >> 8) & 0xFF;
> + st->tx[5] = val & 0xFF;
> + break;
> + case 32:
> + xfer.len = 7;
> + st->tx[3] = (val >> 24) & 0xFF;
> + st->tx[4] = (val >> 16) & 0xFF;
> + st->tx[5] = (val >> 8) & 0xFF;
> + st->tx[6] = val & 0xFF;
> + break;
> + default:
> + ret = -EINVAL;
> + goto unlock;
> + }
>
> ret = spi_sync_transfer(st->spi, &xfer, 1);
> +unlock:
> mutex_unlock(&st->buf_lock);
>
> return ret;
> }
>
> +static int ade7854_spi_write_reg_8(struct device *dev,
> + u16 reg_address,
> + u8 val)
> +{
> + return ade7854_spi_write_reg(dev, reg_address, val, 8);
> +}
> +
> static int ade7854_spi_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);
> - struct spi_transfer xfer = {
> - .tx_buf = st->tx,
> - .bits_per_word = 8,
> - .len = 5,
> - };
> -
> - mutex_lock(&st->buf_lock);
> - st->tx[0] = ADE7854_WRITE_REG;
> - st->tx[1] = (reg_address >> 8) & 0xFF;
> - st->tx[2] = reg_address & 0xFF;
> - st->tx[3] = (val >> 8) & 0xFF;
> - st->tx[4] = val & 0xFF;
> -
> - ret = spi_sync_transfer(st->spi, &xfer, 1);
> - mutex_unlock(&st->buf_lock);
> -
> - return ret;
> + return ade7854_spi_write_reg(dev, reg_address, val, 16);
> }
>
> static int ade7854_spi_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);
> - struct spi_transfer xfer = {
> - .tx_buf = st->tx,
> - .bits_per_word = 8,
> - .len = 6,
> - };
> -
> - mutex_lock(&st->buf_lock);
> - st->tx[0] = ADE7854_WRITE_REG;
> - st->tx[1] = (reg_address >> 8) & 0xFF;
> - st->tx[2] = reg_address & 0xFF;
> - st->tx[3] = (val >> 16) & 0xFF;
> - st->tx[4] = (val >> 8) & 0xFF;
> - st->tx[5] = val & 0xFF;
> -
> - ret = spi_sync_transfer(st->spi, &xfer, 1);
> - mutex_unlock(&st->buf_lock);
> -
> - return ret;
> + return ade7854_spi_write_reg(dev, reg_address, val, 24);
> }
>
> static int ade7854_spi_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);
> - struct spi_transfer xfer = {
> - .tx_buf = st->tx,
> - .bits_per_word = 8,
> - .len = 7,
> - };
> -
> - mutex_lock(&st->buf_lock);
> - st->tx[0] = ADE7854_WRITE_REG;
> - st->tx[1] = (reg_address >> 8) & 0xFF;
> - st->tx[2] = reg_address & 0xFF;
> - st->tx[3] = (val >> 24) & 0xFF;
> - st->tx[4] = (val >> 16) & 0xFF;
> - st->tx[5] = (val >> 8) & 0xFF;
> - st->tx[6] = val & 0xFF;
> -
> - ret = spi_sync_transfer(st->spi, &xfer, 1);
> - mutex_unlock(&st->buf_lock);
> -
> - return ret;
> + return ade7854_spi_write_reg(dev, reg_address, val, 32);
> }
>
> static int ade7854_spi_read_reg_8(struct device *dev,