| Message ID | 20191217075153.23766-1-peter.ujfalusi@ti.com |
|---|---|
| State | Accepted |
| Commit | 735404b846dffcb320264f62b76e6f70012214dd |
| Headers | show |
| Series | iio: adc: stm32-adc: Use dma_request_chan() instead dma_request_slave_channel() | expand |
On Tue, 17 Dec 2019 09:51:53 +0200 Peter Ujfalusi <peter.ujfalusi@ti.com> wrote: > dma_request_slave_channel() is a wrapper on top of dma_request_chan() > eating up the error code. > > By using dma_request_chan() directly the driver can support deferred > probing against DMA. > > Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Hi Peter, Change looks sensible to me, but I'd like to leave a little longer for others to look at this. Give me a poke if I seem to have lost it by the end of the first week in Jan. Thanks, Jonathan > --- > drivers/iio/adc/stm32-adc.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c > index 3b291d72701c..5dab23f1fdee 100644 > --- a/drivers/iio/adc/stm32-adc.c > +++ b/drivers/iio/adc/stm32-adc.c > @@ -1746,9 +1746,15 @@ static int stm32_adc_dma_request(struct iio_dev *indio_dev) > struct dma_slave_config config; > int ret; > > - adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx"); > - if (!adc->dma_chan) > + adc->dma_chan = dma_request_chan(&indio_dev->dev, "rx"); > + if (IS_ERR(adc->dma_chan)) { > + if (PTR_ERR(adc->dma_chan) == -EPROBE_DEFER) > + return -EPROBE_DEFER; > + > + /* Ignore errors to fall back to IRQ mode */ > + adc->dma_chan = NULL; > return 0; > + } > > adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, > STM32_DMA_BUFFER_SIZE,
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c index 3b291d72701c..5dab23f1fdee 100644 --- a/drivers/iio/adc/stm32-adc.c +++ b/drivers/iio/adc/stm32-adc.c @@ -1746,9 +1746,15 @@ static int stm32_adc_dma_request(struct iio_dev *indio_dev) struct dma_slave_config config; int ret; - adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx"); - if (!adc->dma_chan) + adc->dma_chan = dma_request_chan(&indio_dev->dev, "rx"); + if (IS_ERR(adc->dma_chan)) { + if (PTR_ERR(adc->dma_chan) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + /* Ignore errors to fall back to IRQ mode */ + adc->dma_chan = NULL; return 0; + } adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, STM32_DMA_BUFFER_SIZE,
dma_request_slave_channel() is a wrapper on top of dma_request_chan() eating up the error code. By using dma_request_chan() directly the driver can support deferred probing against DMA. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> --- drivers/iio/adc/stm32-adc.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) -- Peter Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki