staging:iio:ade7854: Rework SPI read function

Rework read SPI function to reduce the code duplication and centralizes
all the task in a single function.

Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/staging/iio/meter/ade7854-spi.c b/drivers/staging/iio/meter/ade7854-spi.c
index be7397042850cbc96b370eff7c7214323e0429bb..ee6e4d166ecebb5d0db4593a2c60ae5ef756c65f 100644 (file)
--- a/drivers/staging/iio/meter/ade7854-spi.c
+++ b/drivers/staging/iio/meter/ade7854-spi.c
@@ -67,9 +67,10 @@ static int ade7854_spi_write_reg(struct device *dev,
        return ret;
 }
 
-static int ade7854_spi_read_reg_8(struct device *dev,
-                                 u16 reg_address,
-                                 u8 *val)
+static int ade7854_spi_read_reg(struct device *dev,
+                               u16 reg_address,
+                               u32 *val,
+                               int bits)
 {
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct ade7854_state *st = iio_priv(indio_dev);
@@ -82,7 +83,7 @@ static int ade7854_spi_read_reg_8(struct device *dev,
                }, {
                        .rx_buf = st->rx,
                        .bits_per_word = 8,
-                       .len = 1,
+                       .len = bits,
                }
        };
 
@@ -94,128 +95,57 @@ static int ade7854_spi_read_reg_8(struct device *dev,
 
        ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));
        if (ret) {
-               dev_err(&st->spi->dev, "problem when reading 8 bit register 0x%02X",
+               dev_err(&st->spi->dev, "problem when reading register 0x%02X",
                        reg_address);
-               goto error_ret;
+               goto unlock;
+       }
+
+       switch (bits) {
+       case 8:
+               *val = st->rx[0];
+               break;
+       case 16:
+               *val = be16_to_cpup((const __be16 *)st->rx);
+               break;
+       case 24:
+               *val = (st->rx[0] << 16) | (st->rx[1] << 8) | st->rx[2];
+               break;
+       case 32:
+               *val = be32_to_cpup((const __be32 *)st->rx);
+               break;
        }
-       *val = st->rx[0];
 
-error_ret:
+unlock:
        mutex_unlock(&st->buf_lock);
        return ret;
 }
 
+static int ade7854_spi_read_reg_8(struct device *dev,
+                                 u16 reg_address,
+                                 u8 *val)
+{
+       return ade7854_spi_read_reg(dev, reg_address, (u32 *)val, 8);
+}
+
 static int ade7854_spi_read_reg_16(struct device *dev,
                                   u16 reg_address,
                                   u16 *val)
 {
-       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-       struct ade7854_state *st = iio_priv(indio_dev);
-       int ret;
-       struct spi_transfer xfers[] = {
-               {
-                       .tx_buf = st->tx,
-                       .bits_per_word = 8,
-                       .len = 3,
-               }, {
-                       .rx_buf = st->rx,
-                       .bits_per_word = 8,
-                       .len = 2,
-               }
-       };
-
-       mutex_lock(&st->buf_lock);
-       st->tx[0] = ADE7854_READ_REG;
-       st->tx[1] = (reg_address >> 8) & 0xFF;
-       st->tx[2] = reg_address & 0xFF;
-
-       ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));
-       if (ret) {
-               dev_err(&st->spi->dev, "problem when reading 16 bit register 0x%02X",
-                       reg_address);
-               goto error_ret;
-       }
-       *val = be16_to_cpup((const __be16 *)st->rx);
-
-error_ret:
-       mutex_unlock(&st->buf_lock);
-       return ret;
+       return ade7854_spi_read_reg(dev, reg_address, (u32 *)val, 16);
 }
 
 static int ade7854_spi_read_reg_24(struct device *dev,
                                   u16 reg_address,
                                   u32 *val)
 {
-       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-       struct ade7854_state *st = iio_priv(indio_dev);
-       int ret;
-       struct spi_transfer xfers[] = {
-               {
-                       .tx_buf = st->tx,
-                       .bits_per_word = 8,
-                       .len = 3,
-               }, {
-                       .rx_buf = st->rx,
-                       .bits_per_word = 8,
-                       .len = 3,
-               }
-       };
-
-       mutex_lock(&st->buf_lock);
-
-       st->tx[0] = ADE7854_READ_REG;
-       st->tx[1] = (reg_address >> 8) & 0xFF;
-       st->tx[2] = reg_address & 0xFF;
-
-       ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));
-       if (ret) {
-               dev_err(&st->spi->dev, "problem when reading 24 bit register 0x%02X",
-                       reg_address);
-               goto error_ret;
-       }
-       *val = (st->rx[0] << 16) | (st->rx[1] << 8) | st->rx[2];
-
-error_ret:
-       mutex_unlock(&st->buf_lock);
-       return ret;
+       return ade7854_spi_read_reg(dev, reg_address, (u32 *)val, 24);
 }
 
 static int ade7854_spi_read_reg_32(struct device *dev,
                                   u16 reg_address,
                                   u32 *val)
 {
-       struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-       struct ade7854_state *st = iio_priv(indio_dev);
-       int ret;
-       struct spi_transfer xfers[] = {
-               {
-                       .tx_buf = st->tx,
-                       .bits_per_word = 8,
-                       .len = 3,
-               }, {
-                       .rx_buf = st->rx,
-                       .bits_per_word = 8,
-                       .len = 4,
-               }
-       };
-
-       mutex_lock(&st->buf_lock);
-
-       st->tx[0] = ADE7854_READ_REG;
-       st->tx[1] = (reg_address >> 8) & 0xFF;
-       st->tx[2] = reg_address & 0xFF;
-
-       ret = spi_sync_transfer(st->spi, xfers, ARRAY_SIZE(xfers));
-       if (ret) {
-               dev_err(&st->spi->dev, "problem when reading 32 bit register 0x%02X",
-                       reg_address);
-               goto error_ret;
-       }
-       *val = be32_to_cpup((const __be32 *)st->rx);
-
-error_ret:
-       mutex_unlock(&st->buf_lock);
-       return ret;
+       return ade7854_spi_read_reg(dev, reg_address, (u32 *)val, 32);
 }
 
 static int ade7854_spi_probe(struct spi_device *spi)