iio: adc: stm32-dfsdm: fix device used to request dma

[ Upstream commit b455d06e6fb3c035711e8aab1ca18082ccb15d87 ]

DMA channel request should use device struct from platform device struct.
Currently it's using iio device struct. But at this stage when probing,
device struct isn't yet registered (e.g. device_register is done in
iio_device_register). Since commit 71723a96b8b1 ("dmaengine: Create
symlinks between DMA channels and slaves"), a warning message is printed
as the links in sysfs can't be created, due to device isn't yet registered:
- Cannot create DMA slave symlink
- Cannot create DMA dma:rx symlink

Fix this by using device struct from platform device to request dma chan.

Fixes: eca949800d2d ("IIO: ADC: add stm32 DFSDM support for PDM microphone")

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
index 4a9337a..c2948de 100644 (file)
--- a/drivers/iio/adc/stm32-dfsdm-adc.c
+++ b/drivers/iio/adc/stm32-dfsdm-adc.c
@@ -62,7 +62,7 @@ enum sd_converter_type {
 
 struct stm32_dfsdm_dev_data {
        int type;
-       int (*init)(struct iio_dev *indio_dev);
+       int (*init)(struct device *dev, struct iio_dev *indio_dev);
        unsigned int num_channels;
        const struct regmap_config *regmap_cfg;
 };
@@ -1359,11 +1359,12 @@ static void stm32_dfsdm_dma_release(struct iio_dev *indio_dev)
        }
 }
 
-static int stm32_dfsdm_dma_request(struct iio_dev *indio_dev)
+static int stm32_dfsdm_dma_request(struct device *dev,
+                                  struct iio_dev *indio_dev)
 {
        struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
 
-       adc->dma_chan = dma_request_chan(&indio_dev->dev, "rx");
+       adc->dma_chan = dma_request_chan(dev, "rx");
        if (IS_ERR(adc->dma_chan)) {
                int ret = PTR_ERR(adc->dma_chan);
 
@@ -1419,7 +1420,7 @@ static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev,
                                          &adc->dfsdm->ch_list[ch->channel]);
 }
 
-static int stm32_dfsdm_audio_init(struct iio_dev *indio_dev)
+static int stm32_dfsdm_audio_init(struct device *dev, struct iio_dev *indio_dev)
 {
        struct iio_chan_spec *ch;
        struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
@@ -1446,10 +1447,10 @@ static int stm32_dfsdm_audio_init(struct iio_dev *indio_dev)
        indio_dev->num_channels = 1;
        indio_dev->channels = ch;
 
-       return stm32_dfsdm_dma_request(indio_dev);
+       return stm32_dfsdm_dma_request(dev, indio_dev);
 }
 
-static int stm32_dfsdm_adc_init(struct iio_dev *indio_dev)
+static int stm32_dfsdm_adc_init(struct device *dev, struct iio_dev *indio_dev)
 {
        struct iio_chan_spec *ch;
        struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
@@ -1493,17 +1494,17 @@ static int stm32_dfsdm_adc_init(struct iio_dev *indio_dev)
        init_completion(&adc->completion);
 
        /* Optionally request DMA */
-       ret = stm32_dfsdm_dma_request(indio_dev);
+       ret = stm32_dfsdm_dma_request(dev, indio_dev);
        if (ret) {
                if (ret != -ENODEV) {
                        if (ret != -EPROBE_DEFER)
-                               dev_err(&indio_dev->dev,
+                               dev_err(dev,
                                        "DMA channel request failed with %d\n",
                                        ret);
                        return ret;
                }
 
-               dev_dbg(&indio_dev->dev, "No DMA support\n");
+               dev_dbg(dev, "No DMA support\n");
                return 0;
        }
 
@@ -1616,7 +1617,7 @@ static int stm32_dfsdm_adc_probe(struct platform_device *pdev)
                adc->dfsdm->fl_list[adc->fl_id].sync_mode = val;
 
        adc->dev_data = dev_data;
-       ret = dev_data->init(iio);
+       ret = dev_data->init(dev, iio);
        if (ret < 0)
                return ret;