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authorDmitry Torokhov <dmitry.torokhov@gmail.com>2021-06-02 01:18:11 +0300
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2021-06-02 01:19:52 +0300
commit60b7db914dddcc94f455b62dbcc05b49d78f4cb6 (patch)
treeed080a5df30430cfc153ac86ba0c2d97a41ba338 /drivers/input
parent08729298c4eea5a9bbc0598d92ff47638a97a1ae (diff)
downloadlinux-60b7db914dddcc94f455b62dbcc05b49d78f4cb6.tar.xz
Input: resistive-adc-touch - rework mapping of channels
Instead of iterating over channels establish and use channel map to retrieve data. As a side effect this will silence "uninitialized variable" warnings. Tested-by: Oleksij Rempel <o.rempel@pengutronix.de> Link: https://lore.kernel.org/r/YLXR2brkc4H54xtK@google.com Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Diffstat (limited to 'drivers/input')
-rw-r--r--drivers/input/touchscreen/resistive-adc-touch.c114
1 files 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..ea7dd9d2b2ac 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_Y]];
+
+ if (st->ch_map[GRTS_CH_PRESSURE] < GRTS_MAX_CHANNELS) {
+ press = touch_info[st->ch_map[GRTS_CH_PRESSURE]];
+ } else if (st->ch_map[GRTS_CH_Z1] < GRTS_MAX_CHANNELS) {
+ unsigned int z1 = touch_info[st->ch_map[GRTS_CH_Z1]];
+ unsigned int z2 = touch_info[st->ch_map[GRTS_CH_Z2]];
+ unsigned int Rt;
- if (z1) {
Rt = z2;
Rt -= z1;
Rt *= st->x_plate_ohms;
@@ -142,60 +130,59 @@ static void grts_disable(void *data)
iio_channel_release_all_cb(data);
}
-static int grts_get_properties(struct grts_state *st, struct device *dev)
+static int grts_map_channel(struct grts_state *st, struct device *dev,
+ enum grts_ch_type type, const char *name,
+ bool optional)
{
- int idx, error;
-
- idx = device_property_match_string(dev, "io-channel-names", "x");
- if (idx < 0)
- return idx;
-
- if (idx >= ARRAY_SIZE(st->ch))
+ int idx;
+
+ idx = device_property_match_string(dev, "io-channel-names", name);
+ if (idx < 0) {
+ if (!optional)
+ return idx;
+ idx = GRTS_MAX_CHANNELS;
+ } else if (idx >= GRTS_MAX_CHANNELS) {
return -EOVERFLOW;
+ }
- st->ch[idx] = GRTS_CH_X;
+ st->ch_map[type] = idx;
+ return 0;
+}
- idx = device_property_match_string(dev, "io-channel-names", "y");
- if (idx < 0)
- return idx;
+static int grts_get_properties(struct grts_state *st, struct device *dev)
+{
+ int error;
- if (idx >= ARRAY_SIZE(st->ch))
- return -EOVERFLOW;
+ error = grts_map_channel(st, dev, GRTS_CH_X, "x", false);
+ if (error)
+ return error;
- st->ch[idx] = GRTS_CH_Y;
+ error = grts_map_channel(st, dev, GRTS_CH_Y, "y", false);
+ if (error)
+ return error;
/* pressure is optional */
- idx = device_property_match_string(dev, "io-channel-names", "pressure");
- if (idx >= 0) {
- if (idx >= ARRAY_SIZE(st->ch))
- return -EOVERFLOW;
+ error = grts_map_channel(st, dev, GRTS_CH_PRESSURE, "pressure", true);
+ if (error)
+ return error;
- st->ch[idx] = GRTS_CH_PRESSURE;
+ if (st->ch_map[GRTS_CH_PRESSURE] < GRTS_MAX_CHANNELS) {
st->pressure = true;
-
return 0;
}
/* if no pressure is defined, try optional z1 + z2 */
- idx = device_property_match_string(dev, "io-channel-names", "z1");
- if (idx < 0)
- return 0;
-
- if (idx >= ARRAY_SIZE(st->ch))
- return -EOVERFLOW;
+ error = grts_map_channel(st, dev, GRTS_CH_Z1, "z1", true);
+ if (error)
+ return error;
- st->ch[idx] = GRTS_CH_Z1;
+ if (st->ch_map[GRTS_CH_Z1] >= GRTS_MAX_CHANNELS)
+ return 0;
/* if z1 is provided z2 is not optional */
- idx = device_property_match_string(dev, "io-channel-names", "z2");
- if (idx < 0)
- return idx;
-
- if (idx >= ARRAY_SIZE(st->ch))
- return -EOVERFLOW;
-
- st->ch[idx] = GRTS_CH_Z2;
- st->pressure = true;
+ error = grts_map_channel(st, dev, GRTS_CH_Z2, "z2", true);
+ if (error)
+ return error;
error = device_property_read_u32(dev,
"touchscreen-x-plate-ohms",
@@ -205,6 +192,7 @@ static int grts_get_properties(struct grts_state *st, struct device *dev)
return error;
}
+ st->pressure = true;
return 0;
}