Re: [PATCH v3 7/7] iio: accel: Add support for Kionix/ROHM KX132-1211 accelerometer

Mehdi Djait
2023-05-05T18:11:41Z

Hello Jonathan,

On Mon, May 01, 2023 at 03:56:45PM +0100, Jonathan Cameron wrote:
> On Tue, 25 Apr 2023 00:22:27 +0200
> Mehdi Djait <mehdi.djait.k@gmail.com> wrote:
>
> > Kionix KX132-1211 is a tri-axis 16-bit accelerometer that can support
> > ranges from ±2G to ±16G, digital output through I²C/SPI.
> > Add support for basic accelerometer features such as reading acceleration
> > via IIO using raw reads, triggered buffer (data-ready), or the WMI IRQ.
> >
> > Datasheet: https://kionixfs.azureedge.net/en/document/KX132-1211-Technical-Reference-Manual-Rev-5.0.pdf
> > Signed-off-by: Mehdi Djait <mehdi.djait.k@gmail.com>
>
> Two tiny things inline.
>
> > +static int kx132_get_fifo_bytes(struct kx022a_data *data)
> > +{
> > + struct device *dev = regmap_get_device(data->regmap);
> > + __le16 buf_status;
> > + int ret, fifo_bytes;
> > +
> > + ret = regmap_bulk_read(data->regmap, data->chip_info->buf_status1,
> > + &buf_status, sizeof(buf_status));
> > + if (ret) {
> > + dev_err(dev, "Error reading buffer status\n");
> > + return ret;
> > + }
> > +
> > + fifo_bytes = le16_to_cpu(buf_status);
> > + fifo_bytes &= data->chip_info->buf_smp_lvl_mask;
>
> Slight preference for FIELD_GET() as it saves me checking the mask includes
> lowest bits.

This will mean I have the remove the chip_info member buf_smp_lvl_mask
and use KX132_MASK_BUF_SMP_LVL directly because otherwise the
__builtin_constant_p function will cause an error when building.
Check: https://elixir.bootlin.com/linux/latest/source/include/linux/bitfield.h#L65

I can change it to FIELD_GET() if you want to.

>
>
> > +
> > + return fifo_bytes;
> > +}
> > +
> > static int __kx022a_fifo_flush(struct iio_dev *idev, unsigned int samples,
> > bool irq)
> > {
> > @@ -1036,6 +1157,32 @@ const struct kx022a_chip_info kx022a_chip_info = {
> > };
> > EXPORT_SYMBOL_NS_GPL(kx022a_chip_info, IIO_KX022A);
> >
> > +const struct kx022a_chip_info kx132_chip_info = {
> > + .name = "kx132-1211",
> > + .regmap_config = &kx132_regmap_config,
> > + .channels = kx132_channels,
> > + .num_channels = ARRAY_SIZE(kx132_channels),
> > + .fifo_length = KX132_FIFO_LENGTH,
> > + .who = KX132_REG_WHO,
> > + .id = KX132_ID,
> > + .cntl = KX132_REG_CNTL,
> > + .cntl2 = KX132_REG_CNTL2,
> > + .odcntl = KX132_REG_ODCNTL,
> > + .buf_cntl1 = KX132_REG_BUF_CNTL1,
> > + .buf_cntl2 = KX132_REG_BUF_CNTL2,
> > + .buf_clear = KX132_REG_BUF_CLEAR,
> > + .buf_status1 = KX132_REG_BUF_STATUS_1,
> > + .buf_smp_lvl_mask = KX132_MASK_BUF_SMP_LVL,
>
> There are some things in here (typically where the define isn't used
> anywhere else) where I think it would be easier to follow if the
> value was listed here. Masks and IDs for example.
>

After removing buf_smp_lvl_mask, which members will be easier to understand (besides id) ?

--
Kind Regards
Mehdi Djait