staging:iio:adc:MXS:LRADC: fix touchscreen statemachine

jbeptx · jic23 · commit 760dbe1dcb6d · 2014-02-24T21:55:50.000Z
Releasing the touchscreen lets the internal statemachine left in a wrong state. Due to this the release coordinate will be reported again by accident when the next touchscreen event happens. This change sets up the correct state when waiting for the next touchscreen event. This has led to reported issues with calibrating the touchscreen. Bug was introduced somewhere in the series that began with 18da755 Staging/iio/adc/touchscreen/MXS: add proper clock handling in which the way this driver worked was substantially changed to be interrupt driven rather than relying on a busy loop. This was a regression in the 3.13 kernel. Signed-off-by: Juergen Beisert <jbe@pengutronix.de> Tested-by: Alexandre Belloni <alexandre.belloni@free-electrons.com> Cc: stable@vger.kernel.org Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/staging/iio/adc/mxs-lradc.c b/drivers/staging/iio/adc/mxs-lradc.c
@@ -757,6 +757,7 @@ static void mxs_lradc_finish_touch_event(struct mxs_lradc *lradc, bool valid)
 	}
 
 	/* if it is released, wait for the next touch via IRQ */
+	lradc->cur_plate = LRADC_TOUCH;
 	mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ, LRADC_CTRL1);
 	mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);
 }

Original file line number	Diff line number	Diff line change
`@@ -757,6 +757,7 @@ static void mxs_lradc_finish_touch_event(struct mxs_lradc *lradc, bool valid)`
`757`	`757`	`}`
`758`	`758`
`759`	`759`	`/* if it is released, wait for the next touch via IRQ */`
	`760`	`+ lradc->cur_plate = LRADC_TOUCH;`
`760`	`761`	`mxs_lradc_reg_clear(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ, LRADC_CTRL1);`
`761`	`762`	`mxs_lradc_reg_set(lradc, LRADC_CTRL1_TOUCH_DETECT_IRQ_EN, LRADC_CTRL1);`
`762`	`763`	`}`