Re: [input:next 2732/2735] drivers/input/touchscreen/resistive-adc-touch.c:84 grts_cb() error: uninitialized symbol 'z2'.

On Tue, Jun 01, 2021 at 12:27:15PM +0200, Oleksij Rempel wrote:

Hi Dmitry,

 

quoted

Input: resistive-adc-touch - rework mapping of channels

From: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Instead of iterating over channels establish and use channel map to
retrieve data. As a side effect this will silence "uninitialized variable"
warnings.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/touchscreen/resistive-adc-touch.c |  114 ++++++++++-------------
 1 file changed, 51 insertions(+), 63 deletions(-)

diff --git a/drivers/input/touchscreen/resistive-adc-touch.c b/drivers/input/touchscreen/resistive-adc-touch.c
index ea1884fb49a1..2102916a37ea 100644
--- a/drivers/input/touchscreen/resistive-adc-touch.c
+++ b/drivers/input/touchscreen/resistive-adc-touch.c

@@ -25,12 +25,12 @@
 #define GRTS_MAX_CHANNELS				4
 
 enum grts_ch_type {
-	GRTS_CH_NONE = 0,
 	GRTS_CH_X,
 	GRTS_CH_Y,
 	GRTS_CH_PRESSURE,
 	GRTS_CH_Z1,
 	GRTS_CH_Z2,
+	GRTS_CH_MAX = GRTS_CH_Z2 + 1
 };
 
 /**

@@ -42,7 +42,7 @@ enum grts_ch_type {
  * @iio_cb:		iio_callback buffer for the data
  * @input:		the input device structure that we register
  * @prop:		touchscreen properties struct
- * @ch:			channels that are defined for the touchscreen
+ * @ch_map:		map of channels that are defined for the touchscreen
  */
 struct grts_state {
 	u32				x_plate_ohms;

@@ -52,37 +52,25 @@ struct grts_state {
 	struct iio_cb_buffer		*iio_cb;
 	struct input_dev		*input;
 	struct touchscreen_properties	prop;
-	u8				ch[GRTS_MAX_CHANNELS];
+	u8				ch_map[GRTS_CH_MAX];
 };
 
 static int grts_cb(const void *data, void *private)
 {
 	const u16 *touch_info = data;
 	struct grts_state *st = private;
-	unsigned int x, y, press = 0, z1 = 0, z2;
-	unsigned int Rt, i;
-
-	for (i = 0; i < ARRAY_SIZE(st->ch) && st->ch[i] != GRTS_CH_NONE; i++) {
-		switch (st->ch[i]) {
-		case GRTS_CH_X:
-			x = touch_info[i];
-			break;
-		case GRTS_CH_Y:
-			y = touch_info[i];
-			break;
-		case GRTS_CH_PRESSURE:
-			press = touch_info[i];
-			break;
-		case GRTS_CH_Z1:
-			z1 = touch_info[i];
-			break;
-		case GRTS_CH_Z2:
-			z2 = touch_info[i];
-			break;
-		}
-	}
+	unsigned int x, y, press;
+
+	x = touch_info[st->ch_map[GRTS_CH_X]];
+	y = touch_info[st->ch_map[GRTS_CH_X]];

Here should be GRTS_CH_Y

With this fix:
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>

Thank you Okeksij, I fixed this up and applied.

-- 
Dmitry