On Mon, Oct 19, 2015 at 12:52:50PM +0200, Lars-Peter Clausen wrote: > On 10/16/2015 12:29 PM, Teodora Baluta wrote: > > This patch adds a minimal implementation for the Memsic MXC6255XC > > orientation sensing accelerometer. The supported operations are reading > > raw acceleration values for X/Y axis that can be scaled using the > > exposed scale. > > > > Signed-off-by: Teodora Baluta <teodora.baluta@xxxxxxxxx> > > Looks quite good in general, a few minor things inline. Thanks for the review. I'll send a v2 as soon as possible. > > [...] > > +/* scale value for +/- 2G measurement range */ > > +static const int mxc6255_scale = 153829; > > + > > +static IIO_CONST_ATTR(in_accel_scale_available, MXC6255_SCALE_AVAIL); > > If there is only one scale available it does not make too much sense to have > a scale_available attribute. > > [..] > > +static int mxc6255_read_raw(struct iio_dev *indio_dev, > > + struct iio_chan_spec const *chan, > > + int *val, int *val2, long mask) > > +{ > > + struct mxc6255_data *data = iio_priv(indio_dev); > > + unsigned int reg; > > + int axis = chan->channel2 - 1; > > 1 is a bit of a magic constant here. Use IIO_MOD_X instead. Or even better > use chan->address. > > > + int ret; > > + > > + switch (mask) { > > + case IIO_CHAN_INFO_RAW: > > + ret = regmap_read(data->regmap, > > + MXC6255_AXIS_TO_REG(axis), ®); > > + if (ret < 0) { > > + dev_err(&data->client->dev, > > + "Error reading axis %d\n", axis); > > + return ret; > > + } > > + > > + *val = sign_extend32(reg, 7); > > + return IIO_VAL_INT; > > + case IIO_CHAN_INFO_SCALE: > > + *val = 0; > > + *val2 = mxc6255_scale; > > + return IIO_VAL_INT_PLUS_MICRO; > > + default: > > + return -EINVAL; > > + } > > +} > [...] > > +static int mxc6255_probe(struct i2c_client *client, > > + const struct i2c_device_id *id) > > +{ > [...] > > + ret = regmap_read(data->regmap, MXC6255_REG_CHIP_ID, &chip_id); > > + if (ret < 0) { > > + dev_err(&client->dev, "Error reading chip id %d\n", ret); > > + return ret; > > + } > > Does it make sense to check whether chip ID matches the expected value, to > catch mistakes where the I2C address is incorrect? > > > + > > + dev_dbg(&client->dev, "Chip id %x\n", chip_id); > > + > > + ret = devm_iio_device_register(&client->dev, indio_dev); > > + if (ret < 0) { > > + dev_err(&client->dev, "Could not register IIO device\n"); > > + return ret; > > + } > > + > > + return 0; > > +} > [...] -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html