summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/ads7846.c
diff options
context:
space:
mode:
authorDmitry Torokhov <dmitry.torokhov@gmail.com>2024-07-15 23:03:44 +0200
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2024-07-15 23:03:44 +0200
commita23e1966932464e1c5226cb9ac4ce1d5fc10ba22 (patch)
treebf5f1b57faa01ca31656bfc48c7d6b6f0bc39189 /drivers/input/touchscreen/ads7846.c
parentInput: ads7846 - use spi_device_id table (diff)
parentInput: yealink - simplify locking in sysfs attribute handling (diff)
downloadlinux-a23e1966932464e1c5226cb9ac4ce1d5fc10ba22.tar.xz
linux-a23e1966932464e1c5226cb9ac4ce1d5fc10ba22.zip
Merge branch 'next' into for-linus
Prepare input updates for 6.11 merge window.
Diffstat (limited to 'drivers/input/touchscreen/ads7846.c')
-rw-r--r--drivers/input/touchscreen/ads7846.c35
1 files changed, 29 insertions, 6 deletions
diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index 4d13db13b9e5..4247283c7271 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -138,6 +138,7 @@ struct ads7846 {
void *filter_data;
int (*get_pendown_state)(void);
struct gpio_desc *gpio_pendown;
+ struct gpio_desc *gpio_hsync;
void (*wait_for_sync)(void);
};
@@ -634,10 +635,6 @@ ATTRIBUTE_GROUPS(ads784x);
/*--------------------------------------------------------------------------*/
-static void null_wait_for_sync(void)
-{
-}
-
static int ads7846_debounce_filter(void *ads, int data_idx, int *val)
{
struct ads7846 *ts = ads;
@@ -790,6 +787,28 @@ static int ads7846_filter(struct ads7846 *ts)
return 0;
}
+static void ads7846_wait_for_hsync(struct ads7846 *ts)
+{
+ if (ts->wait_for_sync) {
+ ts->wait_for_sync();
+ return;
+ }
+
+ if (!ts->gpio_hsync)
+ return;
+
+ /*
+ * Wait for HSYNC to assert the line should be flagged
+ * as active low so here we are waiting for it to assert
+ */
+ while (!gpiod_get_value(ts->gpio_hsync))
+ cpu_relax();
+
+ /* Then we wait for it do de-assert */
+ while (gpiod_get_value(ts->gpio_hsync))
+ cpu_relax();
+}
+
static void ads7846_read_state(struct ads7846 *ts)
{
struct ads7846_packet *packet = ts->packet;
@@ -800,7 +819,7 @@ static void ads7846_read_state(struct ads7846 *ts)
packet->last_cmd_idx = 0;
while (true) {
- ts->wait_for_sync();
+ ads7846_wait_for_hsync(ts);
m = &ts->msg[msg_idx];
error = spi_sync(ts->spi, m);
@@ -1268,7 +1287,11 @@ static int ads7846_probe(struct spi_device *spi)
ts->penirq_recheck_delay_usecs =
pdata->penirq_recheck_delay_usecs;
- ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
+ ts->wait_for_sync = pdata->wait_for_sync;
+
+ ts->gpio_hsync = devm_gpiod_get_optional(dev, "ti,hsync", GPIOD_IN);
+ if (IS_ERR(ts->gpio_hsync))
+ return PTR_ERR(ts->gpio_hsync);
snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model);