[PATCH 4/7] iio: adc: stm32-dfsdm: fix multiple channel initialization

Fabrice Gasnier
2018-02-23T12:50:58Z

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>
---
drivers/iio/adc/stm32-dfsdm-adc.c | 39 +++++++++++++++++++++------------------
1 file changed, 21 insertions(+), 18 deletions(-)

diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
index 0eff811..01422d1 100644
--- 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 @@ static int stm32_dfsdm_start_conv(struct stm32_dfsdm_adc *adc, bool dma)

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 @@ static int stm32_dfsdm_postenable(struct iio_dev *indio_dev)
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;
--
1.9.1