[PATCH 15/15] iio: ti_am335x_adc: Properly handle out of memory situation.

[Zubair Lutfullah <zubair.lutfullah@gmail.com>]

From: Russ Dill <Russ.Dill@ti.com>

If we fail to allocate a buffer, unmask the interrupt to allow a retry.
The interrupt handler will be re-run, and our workqueue rescheduled.
If we are able to allocate memory next time around, everything will
continue as normal, otherwise, we will eventually get an underrun.
Before this patch, the driver would stop capturing without any
indication of error to the IIO subsystem or the user.

Signed-off-by: Russ Dill <Russ.Dill@ti.com>
Signed-off-by: Zubair Lutfullah <zubair.lutfullah@gmail.com>
---
 drivers/iio/adc/ti_am335x_adc.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index 00fdb22..5b0efbe 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -212,7 +212,7 @@ static void tiadc_poll_handler(struct work_struct *work_s)
 
 	inputbuffer = kmalloc((fifo1count) * sizeof(u32), GFP_KERNEL);
 	if (inputbuffer == NULL)
-		return;
+		goto out;
 
 	for (i = 0; i < fifo1count; i++) {
 		readx1 = tiadc_readl(adc_dev, REG_FIFO1);
@@ -221,12 +221,14 @@ static void tiadc_poll_handler(struct work_struct *work_s)
 	}
 
 	buffer->access->store_to(buffer, (u8 *) inputbuffer);
+	kfree(inputbuffer);
+
+out:
 	tiadc_writel(adc_dev, REG_IRQSTATUS,
 			IRQENB_FIFO1THRES);
 	tiadc_writel(adc_dev, REG_IRQENABLE,
 			IRQENB_FIFO1THRES);
 
-	kfree(inputbuffer);
 }
 
 static int tiadc_buffer_preenable(struct iio_dev *idev)
-- 
1.7.9.5