From: Ludovic Desroches Date: Thu, 9 Oct 2014 14:02:00 +0000 (+0100) Subject: iio: adc: at91: don't use the last converted data register X-Git-Tag: firefly_0821_release~176^2~3202^2~1^2~1 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=d4f51956ac8ad302db9b0c4e4232775b1baa7b44;p=firefly-linux-kernel-4.4.55.git iio: adc: at91: don't use the last converted data register If touchscreen mode is enabled and a conversion is requested on another channel, the result in the last converted data register can be a touchscreen relative value. Starting a conversion involves to do a conversion for all active channel. It starts with ADC channels and ends with touchscreen channels. Then if ADC_LCD register is not read quickly, its content may be a touchscreen conversion. To remove this temporal constraint, the conversion value is taken from the channel data register. Signed-off-by: Ludovic Desroches Acked-by: Alexandre Belloni Acked-by: Nicolas Ferre Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron --- diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c index 772e869c280e..7eadaf16adc1 100644 --- a/drivers/iio/adc/at91_adc.c +++ b/drivers/iio/adc/at91_adc.c @@ -196,6 +196,7 @@ struct at91_adc_state { bool done; int irq; u16 last_value; + int chnb; struct mutex lock; u8 num_channels; void __iomem *reg_base; @@ -274,7 +275,7 @@ void handle_adc_eoc_trigger(int irq, struct iio_dev *idev) disable_irq_nosync(irq); iio_trigger_poll(idev->trig); } else { - st->last_value = at91_adc_readl(st, AT91_ADC_LCDR); + st->last_value = at91_adc_readl(st, AT91_ADC_CHAN(st, st->chnb)); st->done = true; wake_up_interruptible(&st->wq_data_avail); } @@ -351,7 +352,7 @@ static irqreturn_t at91_adc_rl_interrupt(int irq, void *private) unsigned int reg; status &= at91_adc_readl(st, AT91_ADC_IMR); - if (status & st->registers->drdy_mask) + if (status & GENMASK(st->num_channels - 1, 0)) handle_adc_eoc_trigger(irq, idev); if (status & AT91RL_ADC_IER_PEN) { @@ -418,7 +419,7 @@ static irqreturn_t at91_adc_9x5_interrupt(int irq, void *private) AT91_ADC_IER_YRDY | AT91_ADC_IER_PRDY; - if (status & st->registers->drdy_mask) + if (status & GENMASK(st->num_channels - 1, 0)) handle_adc_eoc_trigger(irq, idev); if (status & AT91_ADC_IER_PEN) { @@ -689,9 +690,10 @@ static int at91_adc_read_raw(struct iio_dev *idev, case IIO_CHAN_INFO_RAW: mutex_lock(&st->lock); + st->chnb = chan->channel; at91_adc_writel(st, AT91_ADC_CHER, AT91_ADC_CH(chan->channel)); - at91_adc_writel(st, AT91_ADC_IER, st->registers->drdy_mask); + at91_adc_writel(st, AT91_ADC_IER, BIT(chan->channel)); at91_adc_writel(st, AT91_ADC_CR, AT91_ADC_START); ret = wait_event_interruptible_timeout(st->wq_data_avail, @@ -708,7 +710,7 @@ static int at91_adc_read_raw(struct iio_dev *idev, at91_adc_writel(st, AT91_ADC_CHDR, AT91_ADC_CH(chan->channel)); - at91_adc_writel(st, AT91_ADC_IDR, st->registers->drdy_mask); + at91_adc_writel(st, AT91_ADC_IDR, BIT(chan->channel)); st->last_value = 0; st->done = false;