iio: mma8452: Add access to registers via DebugFS

Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/accel/mma8452.c b/drivers/iio/accel/mma8452.c
index 001a7dbc863ce1680c372ed9149b0dc831076c57..877ce2954196b0838aebb91d9e530684008d7724 100644 (file)
--- a/drivers/iio/accel/mma8452.c
+++ b/drivers/iio/accel/mma8452.c
@@ -34,6 +34,8 @@
 #define MMA8452_CTRL_REG2 0x2b
 #define MMA8452_CTRL_REG2_RST          BIT(6)
 
+#define MMA8452_MAX_REG 0x31
+
 #define MMA8452_STATUS_DRDY (BIT(2) | BIT(1) | BIT(0))
 
 #define MMA8452_CTRL_DR_MASK (BIT(5) | BIT(4) | BIT(3))
@@ -292,6 +294,28 @@ done:
        return IRQ_HANDLED;
 }
 
+static int mma8452_reg_access_dbg(struct iio_dev *indio_dev,
+                                 unsigned reg, unsigned writeval,
+                                 unsigned *readval)
+{
+       int ret;
+       struct mma8452_data *data = iio_priv(indio_dev);
+
+       if (reg > MMA8452_MAX_REG)
+               return -EINVAL;
+
+       if (!readval)
+               return mma8452_change_config(data, reg, writeval);
+
+       ret = i2c_smbus_read_byte_data(data->client, reg);
+       if (ret < 0)
+               return ret;
+
+       *readval = ret;
+
+       return 0;
+}
+
 #define MMA8452_CHANNEL(axis, idx) { \
        .type = IIO_ACCEL, \
        .modified = 1, \
@@ -331,6 +355,7 @@ static const struct iio_info mma8452_info = {
        .attrs = &mma8452_group,
        .read_raw = &mma8452_read_raw,
        .write_raw = &mma8452_write_raw,
+       .debugfs_reg_access = &mma8452_reg_access_dbg,
        .driver_module = THIS_MODULE,
 };