From f3c034f6177569e1d27a7f3aaa755910201bc2d2 Mon Sep 17 00:00:00 2001 From: Alexandru Ardelean Date: Wed, 4 Mar 2020 10:42:19 +0200 Subject: iio: at91-sama5d2_adc: adjust iio_triggered_buffer_{predisable,postenable} positions The iio_triggered_buffer_{predisable,postenable} functions attach/detach poll functions. In most cases the iio_triggered_buffer_postenable() should be called first to attach the poll function, and then the driver can init the data to be triggered. In this case it's the other way around: the DMA code should be initialized before the attaching the poll function and the reverse should be done when un-initializing. To make things easier when removing the iio_triggered_buffer_postenable() & iio_triggered_buffer_predisable() functions from the IIO core API, the DMA code has been moved into preenable() for init, and postdisable() for uninit. Signed-off-by: Alexandru Ardelean Reviewed-by: Ludovic Desroches Reviewed-by: Eugen Hristev Signed-off-by: Jonathan Cameron --- drivers/iio/adc/at91-sama5d2_adc.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) (limited to 'drivers/iio/adc') diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c index de13ad25b2fe..9abbbdcc7420 100644 --- a/drivers/iio/adc/at91-sama5d2_adc.c +++ b/drivers/iio/adc/at91-sama5d2_adc.c @@ -883,7 +883,7 @@ static bool at91_adc_current_chan_is_touch(struct iio_dev *indio_dev) AT91_SAMA5D2_MAX_CHAN_IDX + 1); } -static int at91_adc_buffer_postenable(struct iio_dev *indio_dev) +static int at91_adc_buffer_preenable(struct iio_dev *indio_dev) { int ret; u8 bit; @@ -934,13 +934,20 @@ static int at91_adc_buffer_postenable(struct iio_dev *indio_dev) if (at91_adc_buffer_check_use_irq(indio_dev, st)) at91_adc_writel(st, AT91_SAMA5D2_IER, AT91_SAMA5D2_IER_DRDY); + return 0; +} + +static int at91_adc_buffer_postenable(struct iio_dev *indio_dev) +{ + if (at91_adc_current_chan_is_touch(indio_dev)) + return 0; + return iio_triggered_buffer_postenable(indio_dev); } -static int at91_adc_buffer_predisable(struct iio_dev *indio_dev) +static int at91_adc_buffer_postdisable(struct iio_dev *indio_dev) { struct at91_adc_state *st = iio_priv(indio_dev); - int ret; u8 bit; /* check if we are disabling triggered buffer or the touchscreen */ @@ -981,19 +988,24 @@ static int at91_adc_buffer_predisable(struct iio_dev *indio_dev) /* read overflow register to clear possible overflow status */ at91_adc_readl(st, AT91_SAMA5D2_OVER); - /* continue with the triggered buffer */ - ret = iio_triggered_buffer_predisable(indio_dev); - if (ret < 0) - dev_err(&indio_dev->dev, "buffer predisable failed\n"); - /* if we are using DMA we must clear registers and end DMA */ if (st->dma_st.dma_chan) dmaengine_terminate_sync(st->dma_st.dma_chan); - return ret; + return 0; +} + +static int at91_adc_buffer_predisable(struct iio_dev *indio_dev) +{ + if (at91_adc_current_chan_is_touch(indio_dev)) + return 0; + + return iio_triggered_buffer_predisable(indio_dev); } static const struct iio_buffer_setup_ops at91_buffer_setup_ops = { + .preenable = &at91_adc_buffer_preenable, + .postdisable = &at91_adc_buffer_postdisable, .postenable = &at91_adc_buffer_postenable, .predisable = &at91_adc_buffer_predisable, }; -- cgit v1.2.3