Le 13/07/2022 à 10:42, Benjamin Bara a écrit :
From: Benjamin Bara <benjamin.bara@xxxxxxxxxxx>
This enables the usage of "can_sleep" GPIO chips as "pin up" GPIO.
This might be the case if the GPIO chip is an expander behind i2c.
Hi,
should you care and/or should there be a v2, some nitpick below.
CJ
Signed-off-by: Benjamin Bara <benjamin.bara@xxxxxxxxxxx>
Signed-off-by: Richard Leitner <richard.leitner@xxxxxxxxxxx>
---
drivers/input/touchscreen/tsc2007.h | 1 +
drivers/input/touchscreen/tsc2007_core.c | 38 ++++++++++++++++++++----
2 files changed, 34 insertions(+), 5 deletions(-)
diff --git a/drivers/input/touchscreen/tsc2007.h b/drivers/input/touchscreen/tsc2007.h
index 69b08dd6c8df..29bd1ff22c72 100644
--- a/drivers/input/touchscreen/tsc2007.h
+++ b/drivers/input/touchscreen/tsc2007.h
@@ -78,6 +78,7 @@ struct tsc2007 {
bool stopped;
int (*get_pendown_state)(struct device *);
+ int (*get_pendown_state_cansleep)(struct device *);
void (*clear_penirq)(void);
struct mutex mlock;
diff --git a/drivers/input/touchscreen/tsc2007_core.c b/drivers/input/touchscreen/tsc2007_core.c
index 3e871d182c40..0ad4c3c41297 100644
--- a/drivers/input/touchscreen/tsc2007_core.c
+++ b/drivers/input/touchscreen/tsc2007_core.c
@@ -20,6 +20,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
@@ -108,6 +109,14 @@ bool tsc2007_is_pen_down(struct tsc2007 *ts)
return ts->get_pendown_state(&ts->client->dev);
}
+bool tsc2007_is_pen_down_cansleep(struct tsc2007 *ts)
+{
+ if (!ts->get_pendown_state_cansleep)
+ return true;
+
+ return ts->get_pendown_state_cansleep(&ts->client->dev);
+}
+
static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
{
struct tsc2007 *ts = handle;
@@ -115,7 +124,7 @@ static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
struct ts_event tc;
u32 rt;
- while (!ts->stopped && tsc2007_is_pen_down(ts)) {
+ while (!ts->stopped && tsc2007_is_pen_down_cansleep(ts)) {
/* pen is down, continue with the measurement */
@@ -125,7 +134,7 @@ static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
rt = tsc2007_calculate_resistance(ts, &tc);
- if (!rt && !ts->get_pendown_state) {
+ if (!rt && !ts->get_pendown_state_cansleep) {
/*
* If pressure reported is 0 and we don't have
* callback to check pendown state, we have to
@@ -229,6 +238,14 @@ static int tsc2007_get_pendown_state_gpio(struct device *dev)
return gpiod_get_value(ts->gpiod);
}
+static int tsc2007_get_pendown_state_gpio_cansleep(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct tsc2007 *ts = i2c_get_clientdata(client);
+
+ return gpiod_get_value_cansleep(ts->gpiod);
+}
+
static int tsc2007_probe_properties(struct device *dev, struct tsc2007 *ts)
{
u32 val32;
@@ -264,10 +281,21 @@ static int tsc2007_probe_properties(struct device *dev, struct tsc2007 *ts)
if (IS_ERR(ts->gpiod))
return PTR_ERR(ts->gpiod);
- if (ts->gpiod)
- ts->get_pendown_state = tsc2007_get_pendown_state_gpio;
- else
+ if (ts->gpiod) {
+ /* to support detection during the hard IRQ, the GPIO chip is required to not sleep.
There should be /* alone on the first line of the comment.
+ * this might be the case if the GPIO is e.g. behind an i2c-based GPIO expander.
+ * it is fine to sleep later in the soft IRQ, as it is threaded.
+ */
+ ts->get_pendown_state_cansleep = tsc2007_get_pendown_state_gpio_cansleep;
+ if (gpiod_to_chip(ts->gpiod) && !gpiod_to_chip(ts->gpiod)->can_sleep) {
+ ts->get_pendown_state = tsc2007_get_pendown_state_gpio;
+ } else {
+ dev_dbg(dev, "Pen down GPIO chip can sleep\n");
+ }
Un-needed extra { } around each branch of this "if".
Just my 2c,
CJ
+
+ } else {
dev_warn(dev, "Pen down GPIO is not specified in properties\n");
+ }
return 0;
}
