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.
Acked-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
---
Changes from v2:
- fix GENMASK indexes
Changes from v1:
- use GENMASK and BIT macros
drivers/iio/adc/at91_adc.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index 3b5bacd..ad51808 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, iio_get_time_ns());
} 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;
--
1.7.9.5
--
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