Messages in this thread | | | Subject | Re: [PATCH v1 2/2] iio: temperature: add driver support for ti tmp117 | From | Lars-Peter Clausen <> | Date | Sun, 21 Mar 2021 06:07:31 +0100 |
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On 3/20/21 7:45 AM, Puranjay Mohan wrote: > TMP117 is a Digital temperature sensor with integrated NV memory. > > Add support for tmp117 driver in iio subsystem. > > Datasheet:-https://www.ti.com/lit/gpn/tmp117 > > Signed-off-by: Puranjay Mohan <puranjay12@gmail.com>
This looks good to me. Just two small bits I overlooked during the first review, sorry for that.
> +}; > + > [...] > +static int tmp117_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *channel, int *val, > + int *val2, long mask) > +{ > + struct tmp117_data *data = iio_priv(indio_dev); > + u16 tmp, off; > + > + switch (mask) { > + case IIO_CHAN_INFO_RAW: > + tmp = tmp117_read_reg(data, TMP117_REG_TEMP); > + *val = tmp; No need for tmp here. Just directly assign to val. > + return IIO_VAL_INT; > + > + case IIO_CHAN_INFO_CALIBBIAS: > + off = tmp117_read_reg(data, TMP117_REG_TEMP_OFFSET); > + *val = ((int16_t)off * (int32_t)TMP117_RESOLUTION) / 10000000; > + *val2 = ((int16_t)off * (int32_t)TMP117_RESOLUTION) % 10000000; > + return IIO_VAL_INT_PLUS_MICRO; > + > + case IIO_CHAN_INFO_SCALE: > + *val = 0; > + *val2 = TMP117_SCALE; > + return IIO_VAL_INT_PLUS_NANO; > + > + default: > + return -EINVAL; > + } > +} > + > +static int tmp117_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *channel, int val, > + int val2, long mask) > +{ > + struct tmp117_data *data = iio_priv(indio_dev); > + u16 off; > + > + switch (mask) { > + case IIO_CHAN_INFO_CALIBBIAS: > + off = ((val * 10000000) + (val2 * 10)) > + / (int32_t)TMP117_RESOLUTION;
This needs some input validation. Writing a too large or too small value will cause an overflow/underflow and a bogus value will be written to the register.
You can either reject invalid values by returning -EINVAL or clamp them into the right range. Up to you how you want to handle this.
> + return tmp117_write_reg(data, TMP117_REG_TEMP_OFFSET, off); > + > + default: > + return -EINVAL; > + } > +}
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