On Fri, 22 Jul 2022 15:07:23 +0200
Marcus Folkesson <marcus.folkesson@xxxxxxxxx> wrote:
> Make it possible to read values upon interrupts.
> Configure Data Ready Signal Output Pin to either HiZ or push-pull and
> use it as interrupt source.
>
> Signed-off-by: Marcus Folkesson <marcus.folkesson@xxxxxxxxx>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Looks good to me.
J
> ---
> drivers/iio/adc/mcp3911.c | 53 +++++++++++++++++++++++++++++++++++++++
> 1 file changed, 53 insertions(+)
>
> diff --git a/drivers/iio/adc/mcp3911.c b/drivers/iio/adc/mcp3911.c
> index 96c0a2a50c7c..7db2c75da4ac 100644
> --- a/drivers/iio/adc/mcp3911.c
> +++ b/drivers/iio/adc/mcp3911.c
> @@ -29,6 +29,7 @@
> #define MCP3911_REG_GAIN 0x09
>
> #define MCP3911_REG_STATUSCOM 0x0a
> +#define MCP3911_STATUSCOM_DRHIZ BIT(12)
> #define MCP3911_STATUSCOM_READ GENMASK(7, 6)
> #define MCP3911_STATUSCOM_CH1_24WIDTH BIT(4)
> #define MCP3911_STATUSCOM_CH0_24WIDTH BIT(3)
> @@ -62,6 +63,7 @@ struct mcp3911 {
> struct regulator *vref;
> struct clk *clki;
> u32 dev_addr;
> + struct iio_trigger *trig;
> struct {
> u32 channels[MCP3911_NUM_CHANNELS];
> s64 ts __aligned(8);
> @@ -346,6 +348,23 @@ static void mcp3911_cleanup_regulator(void *_adc)
> regulator_disable(adc->vref);
> }
>
> +static int mcp3911_set_trigger_state(struct iio_trigger *trig, bool enable)
> +{
> + struct mcp3911 *adc = iio_trigger_get_drvdata(trig);
> +
> + if (enable)
> + enable_irq(adc->spi->irq);
> + else
> + disable_irq(adc->spi->irq);
> +
> + return 0;
> +}
> +
> +static const struct iio_trigger_ops mcp3911_trigger_ops = {
> + .validate_device = iio_trigger_validate_own_device,
> + .set_trigger_state = mcp3911_set_trigger_state,
> +};
> +
> static int mcp3911_probe(struct spi_device *spi)
> {
> struct iio_dev *indio_dev;
> @@ -409,6 +428,15 @@ static int mcp3911_probe(struct spi_device *spi)
> if (ret)
> return ret;
>
> + if (device_property_read_bool(&adc->spi->dev, "microchip,data-ready-hiz"))
> + ret = mcp3911_update(adc, MCP3911_REG_STATUSCOM, MCP3911_STATUSCOM_DRHIZ,
> + 0, 2);
> + else
> + ret = mcp3911_update(adc, MCP3911_REG_STATUSCOM, MCP3911_STATUSCOM_DRHIZ,
> + MCP3911_STATUSCOM_DRHIZ, 2);
> + if (ret)
> + return ret;
> +
> indio_dev->name = spi_get_device_id(spi)->name;
> indio_dev->modes = INDIO_DIRECT_MODE;
> indio_dev->info = &mcp3911_info;
> @@ -419,6 +447,31 @@ static int mcp3911_probe(struct spi_device *spi)
>
> mutex_init(&adc->lock);
>
> + if (spi->irq > 0) {
> + adc->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d",
> + indio_dev->name,
> + iio_device_id(indio_dev));
> + if (!adc->trig)
> + return PTR_ERR(adc->trig);
> +
> + adc->trig->ops = &mcp3911_trigger_ops;
> + iio_trigger_set_drvdata(adc->trig, adc);
> + ret = devm_iio_trigger_register(&spi->dev, adc->trig);
> + if (ret)
> + return ret;
> +
> + /*
> + * The device generates interrupts as long as it is powered up.
> + * Some platforms might not allow the option to power it down so
> + * don't enable the interrupt to avoid extra load on the system.
> + */
> + ret = devm_request_irq(&spi->dev, spi->irq,
> + &iio_trigger_generic_data_rdy_poll, IRQF_NO_AUTOEN | IRQF_ONESHOT,
> + indio_dev->name, adc->trig);
> + if (ret)
> + return ret;
> + }
> +
> ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
> NULL,
> mcp3911_trigger_handler, NULL);
