Merge tag 'iio-fixes-for-5.7a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

First set of IIO fixes for the 5.7 cycle.

Includes one MAINTAINERS update to avoid people getting a lot of bounce
messages and complaining about it.

* MAINTAINERS
  - Drop Stefan Popa's Analog Devices email address in favour of
    Michael Hennerich.
* core
  - Fix handling of dB sysfs inputs.
  - Drop a stray semi colon in macro definition.
* ad5770r
  - Fix an off by one in chec on maximum number of channels.
* ad7192
  - Fix a null pointer de-reference due to the name previously being
    retrieved from the spi_get_device_id call which no longer works as
    the relevant table was removed.
* ad7797
  - Use correct attribute group.
* counter/104-quad-8
  - Add locks to prevent some race conditions.
* inv-mpu6050
  - Fix issues around suspend / resume clashing with runtime PM.
* stm32-adc
  - Fix sleep in invalid context
  - Fix id relative path error in device tree binding doc.
* st_lsm6dsx
  - Fix a read alignment issue on an untagged FIFO.
  - Handle odr for slave to properly compute the FIFO data layout / pattern.
  - Flush the HW FIFO before resettting the device to avoid a race on
    interrupt line 1.
* st_sensors
  - Rely on ODR mask not ODR address to identify if the ODR can be set.
    Some devices have an ODR address of 0.
* ti-ads8344
  - Byte ordering was wrong - fix it.
* xilinx-xadc
  - Fix inverted logic in powering down the second ADC.
  - Fix clearing interrupt when enabling the trigger.
  - Fix configuration of sequencer when in simultaneous sampling mode.
  - Limit initial sampling rate as done for runtime configured ones.

* tag 'iio-fixes-for-5.7a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio:
  MAINTAINERS: remove Stefan Popa's email
  iio: adc: ad7192: fix null pointer de-reference crash during probe
  iio: core: remove extra semi-colon from devm_iio_device_register() macro
  iio: adc: ti-ads8344: properly byte swap value
  iio: imu: inv_mpu6050: fix suspend/resume with runtime power
  iio: st_sensors: rely on odr mask to know if odr can be set
  iio: xilinx-xadc: Make sure not exceed maximum samplerate
  iio: xilinx-xadc: Fix sequencer configuration for aux channels in simultaneous mode
  iio: xilinx-xadc: Fix clearing interrupt when enabling trigger
  iio: xilinx-xadc: Fix ADC-B powerdown
  iio: dac: ad5770r: fix off-by-one check on maximum number of channels
  iio: imu: st_lsm6dsx: flush hw FIFO before resetting the device
  iio: core: Fix handling of 'dB'
  dt-bindings: iio: adc: stm32-adc: fix id relative path
  counter: 104-quad-8: Add lock guards - generic interface
  iio: imu: st_lsm6dsx: specify slave odr in slv_odr
  iio: imu: st_lsm6dsx: fix read misalignment on untagged FIFO
  iio: adc: stm32-adc: fix sleep in atomic context
  iio:ad7797: Use correct attribute_group

1 files changed, 28 insertions, 3 deletions

diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
index 80c3f963527b..ae622ee6d08c 100644
--- a/drivers/iio/adc/stm32-adc.c
+++ b/drivers/iio/adc/stm32-adc.c
@@ -1418,8 +1418,30 @@ static unsigned int stm32_adc_dma_residue(struct stm32_adc *adc)
 static void stm32_adc_dma_buffer_done(void *data)
 {
 	struct iio_dev *indio_dev = data;
+	struct stm32_adc *adc = iio_priv(indio_dev);
+	int residue = stm32_adc_dma_residue(adc);
+
+	/*
+	 * In DMA mode the trigger services of IIO are not used
+	 * (e.g. no call to iio_trigger_poll).
+	 * Calling irq handler associated to the hardware trigger is not
+	 * relevant as the conversions have already been done. Data
+	 * transfers are performed directly in DMA callback instead.
+	 * This implementation avoids to call trigger irq handler that
+	 * may sleep, in an atomic context (DMA irq handler context).
+	 */
+	dev_dbg(&indio_dev->dev, "%s bufi=%d\n", __func__, adc->bufi);
 
-	iio_trigger_poll_chained(indio_dev->trig);
+	while (residue >= indio_dev->scan_bytes) {
+		u16 *buffer = (u16 *)&adc->rx_buf[adc->bufi];
+
+		iio_push_to_buffers(indio_dev, buffer);
+
+		residue -= indio_dev->scan_bytes;
+		adc->bufi += indio_dev->scan_bytes;
+		if (adc->bufi >= adc->rx_buf_sz)
+			adc->bufi = 0;
+	}
 }
 
 static int stm32_adc_dma_start(struct iio_dev *indio_dev)
@@ -1845,6 +1867,7 @@ static int stm32_adc_probe(struct platform_device *pdev)
 {
 	struct iio_dev *indio_dev;
 	struct device *dev = &pdev->dev;
+	irqreturn_t (*handler)(int irq, void *p) = NULL;
 	struct stm32_adc *adc;
 	int ret;
 
@@ -1911,9 +1934,11 @@ static int stm32_adc_probe(struct platform_device *pdev)
 	if (ret < 0)
 		return ret;
 
+	if (!adc->dma_chan)
+		handler = &stm32_adc_trigger_handler;
+
 	ret = iio_triggered_buffer_setup(indio_dev,
-					 &iio_pollfunc_store_time,
-					 &stm32_adc_trigger_handler,
+					 &iio_pollfunc_store_time, handler,
 					 &stm32_adc_buffer_setup_ops);
 	if (ret) {
 		dev_err(&pdev->dev, "buffer setup failed\n");