iio: adc: stm32-dfsdm: fix multiple channel initialization

When several channels are registered (e.g. via st,adc-channels property):
- channels array is wrongly filled in. Only 1st element in array is being
  initialized with last registered channel.
  Fix it by passing reference to relevant channel (e.g. array[index]).
- only last initialized channel can work properly (e.g. unique 'ch_id'
  is used). Converting any other channel result in conversion timeout.
  Fix it by getting rid of 'ch_id', use chan->channel instead.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Acked-by: Arnaud Pouliquen <arnaud.pouliquen@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
index 0eff8119119c8394858b1f3a4f6bc9b0fcf52c52..01422d11753cf39be105b9352e06746927d75731 100644 (file)
--- a/drivers/iio/adc/stm32-dfsdm-adc.c
+++ b/drivers/iio/adc/stm32-dfsdm-adc.c
@@ -54,7 +54,6 @@ struct stm32_dfsdm_adc {
        struct stm32_dfsdm *dfsdm;
        const struct stm32_dfsdm_dev_data *dev_data;
        unsigned int fl_id;
-       unsigned int ch_id;
 
        /* ADC specific */
        unsigned int oversamp;
@@ -384,7 +383,7 @@ static ssize_t dfsdm_adc_audio_set_spiclk(struct iio_dev *indio_dev,
 {
        struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
        struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id];
-       struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[adc->ch_id];
+       struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel];
        unsigned int sample_freq = adc->sample_freq;
        unsigned int spi_freq;
        int ret;
@@ -419,18 +418,20 @@ static ssize_t dfsdm_adc_audio_set_spiclk(struct iio_dev *indio_dev,
        return len;
 }
 
-static int stm32_dfsdm_start_conv(struct stm32_dfsdm_adc *adc, bool dma)
+static int stm32_dfsdm_start_conv(struct stm32_dfsdm_adc *adc,
+                                 const struct iio_chan_spec *chan,
+                                 bool dma)
 {
        struct regmap *regmap = adc->dfsdm->regmap;
        int ret;
        unsigned int dma_en = 0, cont_en = 0;
 
-       ret = stm32_dfsdm_start_channel(adc->dfsdm, adc->ch_id);
+       ret = stm32_dfsdm_start_channel(adc->dfsdm, chan->channel);
        if (ret < 0)
                return ret;
 
        ret = stm32_dfsdm_filter_configure(adc->dfsdm, adc->fl_id,
-                                          adc->ch_id);
+                                          chan->channel);
        if (ret < 0)
                goto stop_channels;
 
@@ -464,12 +465,13 @@ stop_channels:
 
        regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
                           DFSDM_CR1_RCONT_MASK, 0);
-       stm32_dfsdm_stop_channel(adc->dfsdm, adc->ch_id);
+       stm32_dfsdm_stop_channel(adc->dfsdm, chan->channel);
 
        return ret;
 }
 
-static void stm32_dfsdm_stop_conv(struct stm32_dfsdm_adc *adc)
+static void stm32_dfsdm_stop_conv(struct stm32_dfsdm_adc *adc,
+                                 const struct iio_chan_spec *chan)
 {
        struct regmap *regmap = adc->dfsdm->regmap;
 
@@ -482,7 +484,7 @@ static void stm32_dfsdm_stop_conv(struct stm32_dfsdm_adc *adc)
        regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
                           DFSDM_CR1_RCONT_MASK, 0);
 
-       stm32_dfsdm_stop_channel(adc->dfsdm, adc->ch_id);
+       stm32_dfsdm_stop_channel(adc->dfsdm, chan->channel);
 }
 
 static int stm32_dfsdm_set_watermark(struct iio_dev *indio_dev,
@@ -609,6 +611,7 @@ static int stm32_dfsdm_adc_dma_start(struct iio_dev *indio_dev)
 static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
 {
        struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+       const struct iio_chan_spec *chan = &indio_dev->channels[0];
        int ret;
 
        /* Reset adc buffer index */
@@ -618,7 +621,7 @@ static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
        if (ret < 0)
                return ret;
 
-       ret = stm32_dfsdm_start_conv(adc, true);
+       ret = stm32_dfsdm_start_conv(adc, chan, true);
        if (ret) {
                dev_err(&indio_dev->dev, "Can't start conversion\n");
                goto stop_dfsdm;
@@ -635,7 +638,7 @@ static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
        return 0;
 
 err_stop_conv:
-       stm32_dfsdm_stop_conv(adc);
+       stm32_dfsdm_stop_conv(adc, chan);
 stop_dfsdm:
        stm32_dfsdm_stop_dfsdm(adc->dfsdm);
 
@@ -645,11 +648,12 @@ stop_dfsdm:
 static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
 {
        struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+       const struct iio_chan_spec *chan = &indio_dev->channels[0];
 
        if (adc->dma_chan)
                dmaengine_terminate_all(adc->dma_chan);
 
-       stm32_dfsdm_stop_conv(adc);
+       stm32_dfsdm_stop_conv(adc, chan);
 
        stm32_dfsdm_stop_dfsdm(adc->dfsdm);
 
@@ -730,7 +734,7 @@ static int stm32_dfsdm_single_conv(struct iio_dev *indio_dev,
        if (ret < 0)
                goto stop_dfsdm;
 
-       ret = stm32_dfsdm_start_conv(adc, false);
+       ret = stm32_dfsdm_start_conv(adc, chan, false);
        if (ret < 0) {
                regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id),
                                   DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0));
@@ -751,7 +755,7 @@ static int stm32_dfsdm_single_conv(struct iio_dev *indio_dev,
        else
                ret = IIO_VAL_INT;
 
-       stm32_dfsdm_stop_conv(adc);
+       stm32_dfsdm_stop_conv(adc, chan);
 
 stop_dfsdm:
        stm32_dfsdm_stop_dfsdm(adc->dfsdm);
@@ -765,7 +769,7 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev,
 {
        struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
        struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id];
-       struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[adc->ch_id];
+       struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel];
        unsigned int spi_freq = adc->spi_freq;
        int ret = -EINVAL;
 
@@ -972,7 +976,6 @@ static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev,
        }
        ch->scan_type.realbits = 24;
        ch->scan_type.storagebits = 32;
-       adc->ch_id = ch->channel;
 
        return stm32_dfsdm_chan_configure(adc->dfsdm,
                                          &adc->dfsdm->ch_list[ch->channel]);
@@ -1001,7 +1004,7 @@ static int stm32_dfsdm_audio_init(struct iio_dev *indio_dev)
        }
        ch->info_mask_separate = BIT(IIO_CHAN_INFO_SAMP_FREQ);
 
-       d_ch = &adc->dfsdm->ch_list[adc->ch_id];
+       d_ch = &adc->dfsdm->ch_list[ch->channel];
        if (d_ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL)
                adc->spi_freq = adc->dfsdm->spi_master_freq;
 
@@ -1042,8 +1045,8 @@ static int stm32_dfsdm_adc_init(struct iio_dev *indio_dev)
                return -ENOMEM;
 
        for (chan_idx = 0; chan_idx < num_ch; chan_idx++) {
-               ch->scan_index = chan_idx;
-               ret = stm32_dfsdm_adc_chan_init_one(indio_dev, ch);
+               ch[chan_idx].scan_index = chan_idx;
+               ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &ch[chan_idx]);
                if (ret < 0) {
                        dev_err(&indio_dev->dev, "Channels init failed\n");
                        return ret;