iio: adc: mcp3911: add support for interrupts

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@gmail.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220815061625.35568-7-marcus.folkesson@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
Marcus Folkesson 2022-08-15 08:16:22 +02:00 committed by Jonathan Cameron
parent 5db9f38d39
commit 08a65f61db

View File

@ -31,6 +31,7 @@
#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)
@ -64,6 +65,7 @@ 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);
@ -344,6 +346,23 @@ static void mcp3911_cleanup_regulator(void *vref)
regulator_disable(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;
@ -395,6 +414,15 @@ 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;
@ -405,6 +433,31 @@ 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);