[PATCH 13/21] IO: ti_adc: Reset and clear overrun status before capture.

From: Zubair Lutfullah
Date: Wed Jul 17 2013 - 13:30:01 EST


While not pulling out samples, the FIFO will fill up causing an

overrun event. Before starting up another continuous sample, clear that

event.

Signed-off-by: Russ Dill <Russ.Dill@xxxxxx>
Signed-off-by: Zubair Lutfullah <zubair.lutfullah@xxxxxxxxx>
---
drivers/iio/adc/ti_am335x_adc.c | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index 1e48799..eb47385 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -250,22 +250,28 @@ static int tiadc_buffer_postenable(struct iio_dev *idev)
{
struct tiadc_device *adc_dev = iio_priv(idev);
struct iio_buffer *buffer = idev->buffer;
- unsigned int enb, fifo1count;
- int stepnum, i;
+ unsigned int enb, config;
+ int stepnum;
u8 bit;

if (!adc_dev->is_continuous_mode) {
printk("Data cannot be read continuously in one shot mode\n");
return -EINVAL;
} else {
- tiadc_writel(adc_dev, REG_IRQENABLE,
- (IRQENB_FIFO1THRES |
- IRQENB_FIFO1OVRRUN |
- IRQENB_FIFO1UNDRFLW));

- fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
- for (i = 0; i < fifo1count; i++)
- tiadc_readl(adc_dev, REG_FIFO1);
+ config = tiadc_readl(adc_dev, REG_CTRL);
+ tiadc_writel(adc_dev, REG_CTRL,
+ config & ~CNTRLREG_TSCSSENB);
+ tiadc_writel(adc_dev, REG_CTRL,
+ config | CNTRLREG_TSCSSENB);
+
+ tiadc_writel(adc_dev, REG_IRQSTATUS,
+ IRQENB_FIFO1THRES |
+ IRQENB_FIFO1OVRRUN |
+ IRQENB_FIFO1UNDRFLW);
+ tiadc_writel(adc_dev, REG_IRQENABLE,
+ IRQENB_FIFO1THRES |
+ IRQENB_FIFO1OVRRUN);

tiadc_writel(adc_dev, REG_SE, 0x00);
for_each_set_bit(bit, buffer->scan_mask,
--
1.7.9.5

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