Allow user to poll the gpio keypad states in sysfs
Signed-off-by: Clark Li <clark.li86@xxxxxxxxx>
---
drivers/input/keyboard/gpio_keys.c | 38 ++++++++++++++++++++++++++++++--------
1 file changed, 30 insertions(+), 8 deletions(-)
diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c
index b29ca65..d3a0536 100644
--- a/drivers/input/keyboard/gpio_keys.c
+++ b/drivers/input/keyboard/gpio_keys.c
@@ -3,6 +3,7 @@
*
* Copyright 2005 Phil Blundell
* Copyright 2010, 2011 David Jander <david@xxxxxxxxxxx>
+ * Copyright 2014 Clark Li <clark.li86@xxxxxxxxx>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
@@ -49,6 +50,12 @@ struct gpio_keys_drvdata {
struct gpio_button_data data[0];
};
+/** What to display in sysfs attributes */
+enum gpio_attr_display {
+ gpio_attr_display_key,
+ gpio_attr_display_state
+};
+
/*
* SYSFS interface for enabling/disabling keys and switches:
*
@@ -150,6 +157,7 @@ static void gpio_keys_enable_button(struct gpio_button_data *bdata)
* @only_disabled: does caller want only those buttons that are
* currently disabled or all buttons that can be
* disabled
+ * @display: display the key or key state
*
* This function writes buttons that can be disabled to @buf. If
* @only_disabled is true, then @buf contains only those buttons
@@ -158,12 +166,14 @@ static void gpio_keys_enable_button(struct gpio_button_data *bdata)
*/
static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
char *buf, unsigned int type,
- bool only_disabled)
+ bool only_disabled,
+ enum gpio_attr_display display)
{
int n_events = get_n_events_by_type(type);
unsigned long *bits;
ssize_t ret;
int i;
+ int state;
bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
if (!bits)
@@ -178,7 +188,15 @@ static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
if (only_disabled && !bdata->disabled)
continue;
- __set_bit(bdata->button->code, bits);
+ if (display == gpio_attr_display_key)
+ __set_bit(bdata->button->code, bits);
+ else if (display == gpio_attr_display_state) {
+ state = gpio_get_value_cansleep(bdata->button->gpio)
+ ? 1 : 0;
+ state ^= bdata->button->active_low;
+ if (state)
+ __set_bit(bdata->button->code, bits);
+ }
}
ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events);
@@ -251,7 +269,7 @@ out:
return error;
}
-#define ATTR_SHOW_FN(name, type, only_disabled) \
+#define ATTR_SHOW_FN(name, type, only_disabled, display) \
static ssize_t gpio_keys_show_##name(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
@@ -260,22 +278,25 @@ static ssize_t gpio_keys_show_##name(struct device *dev, \
struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
\
return gpio_keys_attr_show_helper(ddata, buf, \
- type, only_disabled); \
+ type, only_disabled, display); \
}
-ATTR_SHOW_FN(keys, EV_KEY, false);
-ATTR_SHOW_FN(switches, EV_SW, false);
-ATTR_SHOW_FN(disabled_keys, EV_KEY, true);
-ATTR_SHOW_FN(disabled_switches, EV_SW, true);
+ATTR_SHOW_FN(keys, EV_KEY, false, gpio_attr_display_key);
+ATTR_SHOW_FN(switches, EV_SW, false, gpio_attr_display_key);
+ATTR_SHOW_FN(states, EV_KEY, false, gpio_attr_display_state);
+ATTR_SHOW_FN(disabled_keys, EV_KEY, true, gpio_attr_display_key);
+ATTR_SHOW_FN(disabled_switches, EV_SW, true, gpio_attr_display_key);
/*
* ATTRIBUTES:
*
* /sys/devices/platform/gpio-keys/keys [ro]
* /sys/devices/platform/gpio-keys/switches [ro]
+ * /sys/devices/platform/gpio-keys/states [ro]
*/
static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL);
static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL);
+static DEVICE_ATTR(states, S_IRUGO, gpio_keys_show_states, NULL);
#define ATTR_STORE_FN(name, type) \
static ssize_t gpio_keys_store_##name(struct device *dev, \
@@ -313,6 +334,7 @@ static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO,
static struct attribute *gpio_keys_attrs[] = {
&dev_attr_keys.attr,
&dev_attr_switches.attr,
+ &dev_attr_states.attr,
&dev_attr_disabled_keys.attr,
&dev_attr_disabled_switches.attr,
NULL,
--
1.8.3.2
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