Allow user to poll the gpio keypad states in sysfs Signed-off-by: Clark Li <[email protected]> --- 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 <[email protected]> + * Copyright 2014 Clark Li <[email protected]> * * 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 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
