*/
#include <linux/module.h>
-#include <linux/version.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/irq.h>
#include <linux/sched.h>
#include <linux/pm.h>
+#include <linux/slab.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/input.h>
-#include <linux/irq.h>
#include <linux/gpio_keys.h>
+#include <linux/workqueue.h>
+#include <linux/gpio.h>
-#include <asm/gpio.h>
+struct gpio_button_data {
+ struct gpio_keys_button *button;
+ struct input_dev *input;
+ struct timer_list timer;
+ struct work_struct work;
+ bool disabled;
+};
-static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
+struct gpio_keys_drvdata {
+ struct input_dev *input;
+ struct mutex disable_lock;
+ unsigned int n_buttons;
+ struct gpio_button_data data[0];
+};
+
+/*
+ * SYSFS interface for enabling/disabling keys and switches:
+ *
+ * There are 4 attributes under /sys/devices/platform/gpio-keys/
+ * keys [ro] - bitmap of keys (EV_KEY) which can be
+ * disabled
+ * switches [ro] - bitmap of switches (EV_SW) which can be
+ * disabled
+ * disabled_keys [rw] - bitmap of keys currently disabled
+ * disabled_switches [rw] - bitmap of switches currently disabled
+ *
+ * Userland can change these values and hence disable event generation
+ * for each key (or switch). Disabling a key means its interrupt line
+ * is disabled.
+ *
+ * For example, if we have following switches set up as gpio-keys:
+ * SW_DOCK = 5
+ * SW_CAMERA_LENS_COVER = 9
+ * SW_KEYPAD_SLIDE = 10
+ * SW_FRONT_PROXIMITY = 11
+ * This is read from switches:
+ * 11-9,5
+ * Next we want to disable proximity (11) and dock (5), we write:
+ * 11,5
+ * to file disabled_switches. Now proximity and dock IRQs are disabled.
+ * This can be verified by reading the file disabled_switches:
+ * 11,5
+ * If we now want to enable proximity (11) switch we write:
+ * 5
+ * to disabled_switches.
+ *
+ * We can disable only those keys which don't allow sharing the irq.
+ */
+
+/**
+ * get_n_events_by_type() - returns maximum number of events per @type
+ * @type: type of button (%EV_KEY, %EV_SW)
+ *
+ * Return value of this function can be used to allocate bitmap
+ * large enough to hold all bits for given type.
+ */
+static inline int get_n_events_by_type(int type)
{
+ BUG_ON(type != EV_SW && type != EV_KEY);
+
+ return (type == EV_KEY) ? KEY_CNT : SW_CNT;
+}
+
+/**
+ * gpio_keys_disable_button() - disables given GPIO button
+ * @bdata: button data for button to be disabled
+ *
+ * Disables button pointed by @bdata. This is done by masking
+ * IRQ line. After this function is called, button won't generate
+ * input events anymore. Note that one can only disable buttons
+ * that don't share IRQs.
+ *
+ * Make sure that @bdata->disable_lock is locked when entering
+ * this function to avoid races when concurrent threads are
+ * disabling buttons at the same time.
+ */
+static void gpio_keys_disable_button(struct gpio_button_data *bdata)
+{
+ if (!bdata->disabled) {
+ /*
+ * Disable IRQ and possible debouncing timer.
+ */
+ disable_irq(gpio_to_irq(bdata->button->gpio));
+ if (bdata->button->debounce_interval)
+ del_timer_sync(&bdata->timer);
+
+ bdata->disabled = true;
+ }
+}
+
+/**
+ * gpio_keys_enable_button() - enables given GPIO button
+ * @bdata: button data for button to be disabled
+ *
+ * Enables given button pointed by @bdata.
+ *
+ * Make sure that @bdata->disable_lock is locked when entering
+ * this function to avoid races with concurrent threads trying
+ * to enable the same button at the same time.
+ */
+static void gpio_keys_enable_button(struct gpio_button_data *bdata)
+{
+ if (bdata->disabled) {
+ enable_irq(gpio_to_irq(bdata->button->gpio));
+ bdata->disabled = false;
+ }
+}
+
+/**
+ * gpio_keys_attr_show_helper() - fill in stringified bitmap of buttons
+ * @ddata: pointer to drvdata
+ * @buf: buffer where stringified bitmap is written
+ * @type: button type (%EV_KEY, %EV_SW)
+ * @only_disabled: does caller want only those buttons that are
+ * currently disabled or all buttons that can be
+ * disabled
+ *
+ * This function writes buttons that can be disabled to @buf. If
+ * @only_disabled is true, then @buf contains only those buttons
+ * that are currently disabled. Returns 0 on success or negative
+ * errno on failure.
+ */
+static ssize_t gpio_keys_attr_show_helper(struct gpio_keys_drvdata *ddata,
+ char *buf, unsigned int type,
+ bool only_disabled)
+{
+ int n_events = get_n_events_by_type(type);
+ unsigned long *bits;
+ ssize_t ret;
int i;
- struct platform_device *pdev = dev_id;
- struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
- struct input_dev *input = platform_get_drvdata(pdev);
- for (i = 0; i < pdata->nbuttons; i++) {
- struct gpio_keys_button *button = &pdata->buttons[i];
- int gpio = button->gpio;
+ bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
+ if (!bits)
+ return -ENOMEM;
- if (irq == gpio_to_irq(gpio)) {
- unsigned int type = button->type ?: EV_KEY;
- int state = (gpio_get_value(gpio) ? 1 : 0) ^ button->active_low;
+ for (i = 0; i < ddata->n_buttons; i++) {
+ struct gpio_button_data *bdata = &ddata->data[i];
- input_event(input, type, button->code, !!state);
- input_sync(input);
+ if (bdata->button->type != type)
+ continue;
+
+ if (only_disabled && !bdata->disabled)
+ continue;
+
+ __set_bit(bdata->button->code, bits);
+ }
+
+ ret = bitmap_scnlistprintf(buf, PAGE_SIZE - 2, bits, n_events);
+ buf[ret++] = '\n';
+ buf[ret] = '\0';
+
+ kfree(bits);
+
+ return ret;
+}
+
+/**
+ * gpio_keys_attr_store_helper() - enable/disable buttons based on given bitmap
+ * @ddata: pointer to drvdata
+ * @buf: buffer from userspace that contains stringified bitmap
+ * @type: button type (%EV_KEY, %EV_SW)
+ *
+ * This function parses stringified bitmap from @buf and disables/enables
+ * GPIO buttons accordinly. Returns 0 on success and negative error
+ * on failure.
+ */
+static ssize_t gpio_keys_attr_store_helper(struct gpio_keys_drvdata *ddata,
+ const char *buf, unsigned int type)
+{
+ int n_events = get_n_events_by_type(type);
+ unsigned long *bits;
+ ssize_t error;
+ int i;
+
+ bits = kcalloc(BITS_TO_LONGS(n_events), sizeof(*bits), GFP_KERNEL);
+ if (!bits)
+ return -ENOMEM;
+
+ error = bitmap_parselist(buf, bits, n_events);
+ if (error)
+ goto out;
+
+ /* First validate */
+ for (i = 0; i < ddata->n_buttons; i++) {
+ struct gpio_button_data *bdata = &ddata->data[i];
+
+ if (bdata->button->type != type)
+ continue;
+
+ if (test_bit(bdata->button->code, bits) &&
+ !bdata->button->can_disable) {
+ error = -EINVAL;
+ goto out;
}
}
+ mutex_lock(&ddata->disable_lock);
+
+ for (i = 0; i < ddata->n_buttons; i++) {
+ struct gpio_button_data *bdata = &ddata->data[i];
+
+ if (bdata->button->type != type)
+ continue;
+
+ if (test_bit(bdata->button->code, bits))
+ gpio_keys_disable_button(bdata);
+ else
+ gpio_keys_enable_button(bdata);
+ }
+
+ mutex_unlock(&ddata->disable_lock);
+
+out:
+ kfree(bits);
+ return error;
+}
+
+#define ATTR_SHOW_FN(name, type, only_disabled) \
+static ssize_t gpio_keys_show_##name(struct device *dev, \
+ struct device_attribute *attr, \
+ char *buf) \
+{ \
+ struct platform_device *pdev = to_platform_device(dev); \
+ struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
+ \
+ return gpio_keys_attr_show_helper(ddata, buf, \
+ type, only_disabled); \
+}
+
+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);
+
+/*
+ * ATTRIBUTES:
+ *
+ * /sys/devices/platform/gpio-keys/keys [ro]
+ * /sys/devices/platform/gpio-keys/switches [ro]
+ */
+static DEVICE_ATTR(keys, S_IRUGO, gpio_keys_show_keys, NULL);
+static DEVICE_ATTR(switches, S_IRUGO, gpio_keys_show_switches, NULL);
+
+#define ATTR_STORE_FN(name, type) \
+static ssize_t gpio_keys_store_##name(struct device *dev, \
+ struct device_attribute *attr, \
+ const char *buf, \
+ size_t count) \
+{ \
+ struct platform_device *pdev = to_platform_device(dev); \
+ struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev); \
+ ssize_t error; \
+ \
+ error = gpio_keys_attr_store_helper(ddata, buf, type); \
+ if (error) \
+ return error; \
+ \
+ return count; \
+}
+
+ATTR_STORE_FN(disabled_keys, EV_KEY);
+ATTR_STORE_FN(disabled_switches, EV_SW);
+
+/*
+ * ATTRIBUTES:
+ *
+ * /sys/devices/platform/gpio-keys/disabled_keys [rw]
+ * /sys/devices/platform/gpio-keys/disables_switches [rw]
+ */
+static DEVICE_ATTR(disabled_keys, S_IWUSR | S_IRUGO,
+ gpio_keys_show_disabled_keys,
+ gpio_keys_store_disabled_keys);
+static DEVICE_ATTR(disabled_switches, S_IWUSR | S_IRUGO,
+ gpio_keys_show_disabled_switches,
+ gpio_keys_store_disabled_switches);
+
+static struct attribute *gpio_keys_attrs[] = {
+ &dev_attr_keys.attr,
+ &dev_attr_switches.attr,
+ &dev_attr_disabled_keys.attr,
+ &dev_attr_disabled_switches.attr,
+ NULL,
+};
+
+static struct attribute_group gpio_keys_attr_group = {
+ .attrs = gpio_keys_attrs,
+};
+
+static void gpio_keys_report_event(struct gpio_button_data *bdata)
+{
+ struct gpio_keys_button *button = bdata->button;
+ struct input_dev *input = bdata->input;
+ unsigned int type = button->type ?: EV_KEY;
+ int state = (gpio_get_value(button->gpio) ? 1 : 0) ^ button->active_low;
+
+ input_event(input, type, button->code, !!state);
+ input_sync(input);
+}
+
+static void gpio_keys_work_func(struct work_struct *work)
+{
+ struct gpio_button_data *bdata =
+ container_of(work, struct gpio_button_data, work);
+
+ gpio_keys_report_event(bdata);
+}
+
+static void gpio_keys_timer(unsigned long _data)
+{
+ struct gpio_button_data *data = (struct gpio_button_data *)_data;
+
+ schedule_work(&data->work);
+}
+
+static irqreturn_t gpio_keys_isr(int irq, void *dev_id)
+{
+ struct gpio_button_data *bdata = dev_id;
+ struct gpio_keys_button *button = bdata->button;
+
+ BUG_ON(irq != gpio_to_irq(button->gpio));
+
+ if (button->debounce_interval)
+ mod_timer(&bdata->timer,
+ jiffies + msecs_to_jiffies(button->debounce_interval));
+ else
+ schedule_work(&bdata->work);
+
return IRQ_HANDLED;
}
+static int __devinit gpio_keys_setup_key(struct platform_device *pdev,
+ struct gpio_button_data *bdata,
+ struct gpio_keys_button *button)
+{
+ char *desc = button->desc ? button->desc : "gpio_keys";
+ struct device *dev = &pdev->dev;
+ unsigned long irqflags;
+ int irq, error;
+
+ setup_timer(&bdata->timer, gpio_keys_timer, (unsigned long)bdata);
+ INIT_WORK(&bdata->work, gpio_keys_work_func);
+
+ error = gpio_request(button->gpio, desc);
+ if (error < 0) {
+ dev_err(dev, "failed to request GPIO %d, error %d\n",
+ button->gpio, error);
+ goto fail2;
+ }
+
+ error = gpio_direction_input(button->gpio);
+ if (error < 0) {
+ dev_err(dev, "failed to configure"
+ " direction for GPIO %d, error %d\n",
+ button->gpio, error);
+ goto fail3;
+ }
+
+ irq = gpio_to_irq(button->gpio);
+ if (irq < 0) {
+ error = irq;
+ dev_err(dev, "Unable to get irq number for GPIO %d, error %d\n",
+ button->gpio, error);
+ goto fail3;
+ }
+
+ irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;
+ /*
+ * If platform has specified that the button can be disabled,
+ * we don't want it to share the interrupt line.
+ */
+ if (!button->can_disable)
+ irqflags |= IRQF_SHARED;
+
+ error = request_irq(irq, gpio_keys_isr, irqflags, desc, bdata);
+ if (error) {
+ dev_err(dev, "Unable to claim irq %d; error %d\n",
+ irq, error);
+ goto fail3;
+ }
+
+ return 0;
+
+fail3:
+ gpio_free(button->gpio);
+fail2:
+ return error;
+}
+
static int __devinit gpio_keys_probe(struct platform_device *pdev)
{
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
+ struct gpio_keys_drvdata *ddata;
+ struct device *dev = &pdev->dev;
struct input_dev *input;
int i, error;
+ int wakeup = 0;
+ ddata = kzalloc(sizeof(struct gpio_keys_drvdata) +
+ pdata->nbuttons * sizeof(struct gpio_button_data),
+ GFP_KERNEL);
input = input_allocate_device();
- if (!input)
- return -ENOMEM;
+ if (!ddata || !input) {
+ dev_err(dev, "failed to allocate state\n");
+ error = -ENOMEM;
+ goto fail1;
+ }
- platform_set_drvdata(pdev, input);
+ ddata->input = input;
+ ddata->n_buttons = pdata->nbuttons;
+ mutex_init(&ddata->disable_lock);
- input->evbit[0] = BIT(EV_KEY);
+ platform_set_drvdata(pdev, ddata);
input->name = pdev->name;
input->phys = "gpio-keys/input0";
input->id.product = 0x0001;
input->id.version = 0x0100;
+ /* Enable auto repeat feature of Linux input subsystem */
+ if (pdata->rep)
+ __set_bit(EV_REP, input->evbit);
+
for (i = 0; i < pdata->nbuttons; i++) {
struct gpio_keys_button *button = &pdata->buttons[i];
- int irq = gpio_to_irq(button->gpio);
+ struct gpio_button_data *bdata = &ddata->data[i];
unsigned int type = button->type ?: EV_KEY;
- set_irq_type(irq, IRQ_TYPE_EDGE_BOTH);
- error = request_irq(irq, gpio_keys_isr, IRQF_SAMPLE_RANDOM,
- button->desc ? button->desc : "gpio_keys",
- pdev);
- if (error) {
- printk(KERN_ERR "gpio-keys: unable to claim irq %d; error %d\n",
- irq, error);
- goto fail;
- }
+ bdata->input = input;
+ bdata->button = button;
+
+ error = gpio_keys_setup_key(pdev, bdata, button);
+ if (error)
+ goto fail2;
+
+ if (button->wakeup)
+ wakeup = 1;
input_set_capability(input, type, button->code);
}
+ error = sysfs_create_group(&pdev->dev.kobj, &gpio_keys_attr_group);
+ if (error) {
+ dev_err(dev, "Unable to export keys/switches, error: %d\n",
+ error);
+ goto fail2;
+ }
+
error = input_register_device(input);
if (error) {
- printk(KERN_ERR "Unable to register gpio-keys input device\n");
- goto fail;
+ dev_err(dev, "Unable to register input device, error: %d\n",
+ error);
+ goto fail3;
}
+ /* get current state of buttons */
+ for (i = 0; i < pdata->nbuttons; i++)
+ gpio_keys_report_event(&ddata->data[i]);
+ input_sync(input);
+
+ device_init_wakeup(&pdev->dev, wakeup);
+
return 0;
- fail:
- for (i = i - 1; i >= 0; i--)
- free_irq(gpio_to_irq(pdata->buttons[i].gpio), pdev);
+ fail3:
+ sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
+ fail2:
+ while (--i >= 0) {
+ free_irq(gpio_to_irq(pdata->buttons[i].gpio), &ddata->data[i]);
+ if (pdata->buttons[i].debounce_interval)
+ del_timer_sync(&ddata->data[i].timer);
+ cancel_work_sync(&ddata->data[i].work);
+ gpio_free(pdata->buttons[i].gpio);
+ }
+ platform_set_drvdata(pdev, NULL);
+ fail1:
input_free_device(input);
+ kfree(ddata);
return error;
}
static int __devexit gpio_keys_remove(struct platform_device *pdev)
{
struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
- struct input_dev *input = platform_get_drvdata(pdev);
+ struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
+ struct input_dev *input = ddata->input;
int i;
+ sysfs_remove_group(&pdev->dev.kobj, &gpio_keys_attr_group);
+
+ device_init_wakeup(&pdev->dev, 0);
+
for (i = 0; i < pdata->nbuttons; i++) {
int irq = gpio_to_irq(pdata->buttons[i].gpio);
- free_irq(irq, pdev);
+ free_irq(irq, &ddata->data[i]);
+ if (pdata->buttons[i].debounce_interval)
+ del_timer_sync(&ddata->data[i].timer);
+ cancel_work_sync(&ddata->data[i].work);
+ gpio_free(pdata->buttons[i].gpio);
}
input_unregister_device(input);
return 0;
}
-struct platform_driver gpio_keys_device_driver = {
+
+#ifdef CONFIG_PM
+static int gpio_keys_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
+ int i;
+
+ if (device_may_wakeup(&pdev->dev)) {
+ for (i = 0; i < pdata->nbuttons; i++) {
+ struct gpio_keys_button *button = &pdata->buttons[i];
+ if (button->wakeup) {
+ int irq = gpio_to_irq(button->gpio);
+ enable_irq_wake(irq);
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int gpio_keys_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct gpio_keys_drvdata *ddata = platform_get_drvdata(pdev);
+ struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
+ int i;
+
+ for (i = 0; i < pdata->nbuttons; i++) {
+
+ struct gpio_keys_button *button = &pdata->buttons[i];
+ if (button->wakeup && device_may_wakeup(&pdev->dev)) {
+ int irq = gpio_to_irq(button->gpio);
+ disable_irq_wake(irq);
+ }
+
+ gpio_keys_report_event(&ddata->data[i]);
+ }
+ input_sync(ddata->input);
+
+ return 0;
+}
+
+static const struct dev_pm_ops gpio_keys_pm_ops = {
+ .suspend = gpio_keys_suspend,
+ .resume = gpio_keys_resume,
+};
+#endif
+
+static struct platform_driver gpio_keys_device_driver = {
.probe = gpio_keys_probe,
.remove = __devexit_p(gpio_keys_remove),
.driver = {
.name = "gpio-keys",
+ .owner = THIS_MODULE,
+#ifdef CONFIG_PM
+ .pm = &gpio_keys_pm_ops,
+#endif
}
};
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Phil Blundell <pb@handhelds.org>");
MODULE_DESCRIPTION("Keyboard driver for CPU GPIOs");
+MODULE_ALIAS("platform:gpio-keys");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff