gpio-button-hotplug: support interrupt properties

Upstream Linux's input gpio-keys driver supports
specifying a external interrupt for a gpio via the
'interrupts' properties as well as having support
for software debounce.

This patch ports these features to OpenWrt's event
version. Only the "pure" interrupt-driven support is
left behind, since this goes a bit against the "gpio"
in the "gpio-keys" and I don't have a real device to
test this with.

This patch also silences the generated warnings showing
up since 4.14 due to the 'constification' of the
struct gpio_keys_button *buttons variable in the
upstream struct gpio_keys_platform_data declaration.

gpio-button-hotplug.c: In function 'gpio_keys_get_devtree_pdata':
gpio-button-hotplug.c:392:10: warning: assignment discards 'const'
	qualifier from pointer target type [-Wdiscarded-qualifiers]
   button = &pdata->buttons[i++];
          ^
gpio-button-hotplug.c: In function 'gpio_keys_button_probe':
gpio-button-hotplug.c:537:12: warning: assignment discards 'const'
	qualifier from pointer target type [-Wdiscarded-qualifiers]
   bdata->b = &pdata->buttons[i];
            ^
gpio-button-hotplug.c: In function 'gpio_keys_probe':
gpio-button-hotplug.c:563:37: warning: initialization discards 'const'
	qualifier from pointer target type [-Wdiscarded-qualifiers]
   struct gpio_keys_button *button = &pdata->buttons[i];
                                   ^
Acked-by: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
openwrt-19.07
Christian Lamparter 2019-05-19 16:06:34 +02:00
parent 678ee30ee4
commit afc056d7dc
1 changed files with 93 additions and 21 deletions

View File

@ -26,6 +26,7 @@
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/of_gpio.h>
#include <linux/of_irq.h>
#include <linux/gpio_keys.h>
#define DRV_NAME "gpio-keys"
@ -70,7 +71,10 @@ struct gpio_keys_button_data {
int count;
int threshold;
int can_sleep;
struct gpio_keys_button *b;
int irq;
unsigned int software_debounce;
struct gpio_desc *gpiod;
const struct gpio_keys_button *b;
};
extern u64 uevent_next_seqnum(void);
@ -298,7 +302,7 @@ static void gpio_keys_polled_check_state(struct gpio_keys_button_data *bdata)
return;
}
if ((bdata->last_state != -1) || (type == EV_SW))
if (bdata->last_state != -1 || type == EV_SW)
button_hotplug_event(bdata, type, state);
bdata->last_state = state;
@ -340,11 +344,29 @@ static void gpio_keys_polled_close(struct gpio_keys_button_dev *bdev)
pdata->disable(bdev->dev);
}
static void gpio_keys_irq_work_func(struct work_struct *work)
{
struct gpio_keys_button_data *bdata = container_of(work,
struct gpio_keys_button_data, work.work);
int state = gpio_button_get_value(bdata);
if (state != bdata->last_state) {
unsigned int type = bdata->b->type ?: EV_KEY;
if (bdata->last_state != -1 || type == EV_SW)
button_hotplug_event(bdata, type, state);
bdata->last_state = state;
}
}
static irqreturn_t button_handle_irq(int irq, void *_bdata)
{
struct gpio_keys_button_data *bdata = (struct gpio_keys_button_data *) _bdata;
struct gpio_keys_button_data *bdata =
(struct gpio_keys_button_data *) _bdata;
button_hotplug_event(bdata, bdata->b->type ?: EV_KEY, gpio_button_get_value(bdata));
schedule_delayed_work(&bdata->work,
msecs_to_jiffies(bdata->software_debounce));
return IRQ_HANDLED;
}
@ -390,7 +412,9 @@ gpio_keys_get_devtree_pdata(struct device *dev)
continue;
}
button = &pdata->buttons[i++];
button = (struct gpio_keys_button *)(&pdata->buttons[i++]);
button->irq = irq_of_parse_and_map(pp, 0);
button->gpio = of_get_gpio_flags(pp, 0, &flags);
if (button->gpio < 0) {
@ -517,6 +541,9 @@ static int gpio_keys_button_probe(struct platform_device *pdev,
gpio, error);
return error;
}
bdata->gpiod = gpio_to_desc(gpio);
if (!bdata->gpiod)
return -EINVAL;
error = gpio_direction_input(gpio);
if (error) {
@ -529,12 +556,26 @@ static int gpio_keys_button_probe(struct platform_device *pdev,
bdata->can_sleep = gpio_cansleep(gpio);
bdata->last_state = -1;
if (bdev->polled)
if (bdev->polled) {
bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
pdata->poll_interval);
else
pdata->poll_interval);
} else {
bdata->threshold = 1;
if (button->debounce_interval) {
error = gpiod_set_debounce(bdata->gpiod,
button->debounce_interval * 1000);
/*
* use timer if gpiolib doesn't provide
* debounce.
*/
if (error < 0) {
bdata->software_debounce =
button->debounce_interval;
}
}
}
bdata->b = &pdata->buttons[i];
}
@ -561,23 +602,39 @@ static int gpio_keys_probe(struct platform_device *pdev)
pdata = bdev->pdata;
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button *button = &pdata->buttons[i];
const struct gpio_keys_button *button = &pdata->buttons[i];
struct gpio_keys_button_data *bdata = &bdev->data[i];
unsigned long irqflags = IRQF_ONESHOT;
if (!button->irq)
button->irq = gpio_to_irq(button->gpio);
if (button->irq < 0) {
dev_err(&pdev->dev, "failed to get irq for gpio:%d\n", button->gpio);
continue;
if (!button->irq) {
bdata->irq = gpio_to_irq(button->gpio);
if (bdata->irq < 0) {
dev_err(&pdev->dev, "failed to get irq for gpio:%d\n",
button->gpio);
continue;
}
irqflags |= IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
} else {
bdata->irq = button->irq;
}
ret = devm_request_threaded_irq(&pdev->dev, button->irq, NULL, button_handle_irq,
IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
dev_name(&pdev->dev), bdata);
if (ret < 0)
dev_err(&pdev->dev, "failed to request irq:%d for gpio:%d\n", button->irq, button->gpio);
else
dev_dbg(&pdev->dev, "gpio:%d has irq:%d\n", button->gpio, button->irq);
INIT_DELAYED_WORK(&bdata->work, gpio_keys_irq_work_func);
ret = devm_request_threaded_irq(&pdev->dev,
bdata->irq, NULL, button_handle_irq,
irqflags, dev_name(&pdev->dev), bdata);
if (ret < 0) {
bdata->irq = 0;
dev_err(&pdev->dev, "failed to request irq:%d for gpio:%d\n",
bdata->irq, button->gpio);
continue;
} else {
dev_dbg(&pdev->dev, "gpio:%d has irq:%d\n",
button->gpio, bdata->irq);
}
if (bdata->b->type == EV_SW)
button_hotplug_event(bdata, EV_SW, gpio_button_get_value(bdata));
@ -613,6 +670,19 @@ static int gpio_keys_polled_probe(struct platform_device *pdev)
return ret;
}
static void gpio_keys_irq_close(struct gpio_keys_button_dev *bdev)
{
struct gpio_keys_platform_data *pdata = bdev->pdata;
size_t i;
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button_data *bdata = &bdev->data[i];
disable_irq(bdata->irq);
cancel_delayed_work_sync(&bdata->work);
}
}
static int gpio_keys_remove(struct platform_device *pdev)
{
struct gpio_keys_button_dev *bdev = platform_get_drvdata(pdev);
@ -621,6 +691,8 @@ static int gpio_keys_remove(struct platform_device *pdev)
if (bdev->polled)
gpio_keys_polled_close(bdev);
else
gpio_keys_irq_close(bdev);
return 0;
}