From caf9c1e59809347690584178ed17b76334acbf39 Mon Sep 17 00:00:00 2001 From: Fabrice Gasnier Date: Thu, 21 Mar 2019 17:47:24 +0100 Subject: [PATCH] iio: adc: stm32-dfsdm: move dma enable from start_conv() to start_dma() Move DMA enable (e.g. set RDMAEN bit) away from start_conv() that is used for both buffer and single conversions. Thus, single conv rely on interrupt, not dma. Note: take care to prepare all DMA stuff and set RDMAEN before starting filter (can be set only when DFEN=0). This is precursor patch to ease support of triggered buffer mode. Signed-off-by: Fabrice Gasnier Signed-off-by: Jonathan Cameron --- drivers/iio/adc/stm32-dfsdm-adc.c | 77 +++++++++++++++++++-------------------- 1 file changed, 38 insertions(+), 39 deletions(-) diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c index 8690672b8539..818627fd5413 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -429,12 +429,10 @@ static ssize_t dfsdm_adc_audio_set_spiclk(struct iio_dev *indio_dev, } static int stm32_dfsdm_start_conv(struct stm32_dfsdm_adc *adc, - const struct iio_chan_spec *chan, - bool dma) + const struct iio_chan_spec *chan) { struct regmap *regmap = adc->dfsdm->regmap; int ret; - unsigned int dma_en = 0; ret = stm32_dfsdm_start_channel(adc->dfsdm, chan->channel); if (ret < 0) @@ -444,25 +442,12 @@ static int stm32_dfsdm_start_conv(struct stm32_dfsdm_adc *adc, if (ret < 0) goto stop_channels; - if (dma) { - /* Enable DMA transfer*/ - dma_en = DFSDM_CR1_RDMAEN(1); - } - /* Enable DMA transfer*/ - ret = regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), - DFSDM_CR1_RDMAEN_MASK, dma_en); - if (ret < 0) - goto filter_unconfigure; - ret = stm32_dfsdm_start_filter(adc->dfsdm, adc->fl_id); if (ret < 0) - goto stop_dma; + goto filter_unconfigure; return 0; -stop_dma: - regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), - DFSDM_CR1_RDMAEN_MASK, 0); filter_unconfigure: regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), DFSDM_CR1_CFG_MASK, 0); @@ -479,10 +464,6 @@ static void stm32_dfsdm_stop_conv(struct stm32_dfsdm_adc *adc, stm32_dfsdm_stop_filter(adc->dfsdm, adc->fl_id); - /* Clean conversion options */ - regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), - DFSDM_CR1_RDMAEN_MASK, 0); - regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), DFSDM_CR1_CFG_MASK, 0); @@ -599,15 +580,36 @@ static int stm32_dfsdm_adc_dma_start(struct iio_dev *indio_dev) cookie = dmaengine_submit(desc); ret = dma_submit_error(cookie); - if (ret) { - dmaengine_terminate_all(adc->dma_chan); - return ret; - } + if (ret) + goto err_stop_dma; /* Issue pending DMA requests */ dma_async_issue_pending(adc->dma_chan); + /* Enable DMA transfer*/ + ret = regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id), + DFSDM_CR1_RDMAEN_MASK, DFSDM_CR1_RDMAEN_MASK); + if (ret < 0) + goto err_stop_dma; + return 0; + +err_stop_dma: + dmaengine_terminate_all(adc->dma_chan); + + return ret; +} + +static void stm32_dfsdm_adc_dma_stop(struct iio_dev *indio_dev) +{ + struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); + + if (!adc->dma_chan) + return; + + regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id), + DFSDM_CR1_RDMAEN_MASK, 0); + dmaengine_terminate_all(adc->dma_chan); } static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) @@ -623,24 +625,22 @@ static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) if (ret < 0) return ret; - ret = stm32_dfsdm_start_conv(adc, chan, true); + ret = stm32_dfsdm_adc_dma_start(indio_dev); if (ret) { - dev_err(&indio_dev->dev, "Can't start conversion\n"); + dev_err(&indio_dev->dev, "Can't start DMA\n"); goto stop_dfsdm; } - if (adc->dma_chan) { - ret = stm32_dfsdm_adc_dma_start(indio_dev); - if (ret) { - dev_err(&indio_dev->dev, "Can't start DMA\n"); - goto err_stop_conv; - } + ret = stm32_dfsdm_start_conv(adc, chan); + if (ret) { + dev_err(&indio_dev->dev, "Can't start conversion\n"); + goto err_stop_dma; } return 0; -err_stop_conv: - stm32_dfsdm_stop_conv(adc, chan); +err_stop_dma: + stm32_dfsdm_adc_dma_stop(indio_dev); stop_dfsdm: stm32_dfsdm_stop_dfsdm(adc->dfsdm); @@ -652,11 +652,10 @@ 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, chan); + stm32_dfsdm_adc_dma_stop(indio_dev); + stm32_dfsdm_stop_dfsdm(adc->dfsdm); return 0; @@ -736,7 +735,7 @@ static int stm32_dfsdm_single_conv(struct iio_dev *indio_dev, if (ret < 0) goto stop_dfsdm; - ret = stm32_dfsdm_start_conv(adc, chan, false); + ret = stm32_dfsdm_start_conv(adc, chan); if (ret < 0) { regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); -- 2.11.0