gpio-button-hotplug: fix crash on remove
[openwrt/openwrt.git] / package / kernel / gpio-button-hotplug / src / gpio-button-hotplug.c
index 74c2ecaa2edba76a49cce168a2233ecef42d708b..780736c89bb66c1904a718514f10ec7ad6b47813 100644 (file)
 #include <linux/netlink.h>
 #include <linux/kobject.h>
 #include <linux/input.h>
+#include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/of_gpio.h>
 #include <linux/gpio_keys.h>
 
-#define DRV_NAME       "gpio-keys-polled"
+#define DRV_NAME       "gpio-keys"
 
 #define BH_SKB_SIZE    2048
 
@@ -69,6 +70,7 @@ struct gpio_keys_button_data {
        int count;
        int threshold;
        int can_sleep;
+       struct gpio_keys_button *b;
 };
 
 extern u64 uevent_next_seqnum(void);
@@ -90,6 +92,7 @@ static struct bh_map button_map[] = {
        BH_MAP(BTN_7,           "BTN_7"),
        BH_MAP(BTN_8,           "BTN_8"),
        BH_MAP(BTN_9,           "BTN_9"),
+       BH_MAP(KEY_POWER,       "power"),
        BH_MAP(KEY_RESTART,     "reset"),
        BH_MAP(KEY_RFKILL,      "rfkill"),
        BH_MAP(KEY_WPS_BUTTON,  "wps"),
@@ -139,20 +142,7 @@ static int button_hotplug_fill_event(struct bh_event *event)
        if (ret)
                return ret;
 
-       char *s;
-       switch (event->type) {
-               case EV_KEY:
-                       s = "button";
-                       break;
-               case EV_SW:
-                       s = "switch";
-                       break;
-               default:
-                       s = "button";
-                       break;
-       }
-
-       ret = bh_event_add_var(event, 0, "SUBSYSTEM=%s", s);
+       ret = bh_event_add_var(event, 0, "SUBSYSTEM=%s", "button");
        if (ret)
                return ret;
 
@@ -164,6 +154,12 @@ static int button_hotplug_fill_event(struct bh_event *event)
        if (ret)
                return ret;
 
+       if (event->type == EV_SW) {
+               ret = bh_event_add_var(event, 0, "TYPE=%s", "switch");
+               if (ret)
+                       return ret;
+       }
+
        ret = bh_event_add_var(event, 0, "SEEN=%ld", event->seen);
        if (ret)
                return ret;
@@ -240,18 +236,18 @@ static int button_get_index(unsigned int code)
 }
 
 static void button_hotplug_event(struct gpio_keys_button_data *data,
-                          unsigned int type, unsigned int code, int value)
+                          unsigned int type, int value)
 {
        struct bh_priv *priv = &data->bh;
        unsigned long seen = jiffies;
        int btn;
 
-       BH_DBG("event type=%u, code=%u, value=%d\n", type, code, value);
+       BH_DBG("event type=%u, code=%u, value=%d\n", type, data->b->code, value);
 
        if ((type != EV_KEY) && (type != EV_SW))
                return;
 
-       btn = button_get_index(code);
+       btn = button_get_index(data->b->code);
        if (btn < 0)
                return;
 
@@ -261,12 +257,13 @@ static void button_hotplug_event(struct gpio_keys_button_data *data,
 }
 #else
 static void button_hotplug_event(struct gpio_keys_button_data *data,
-                          unsigned int type, unsigned int code, int value)
+                          unsigned int type, int value)
 {
 }
 #endif /* CONFIG_HOTPLUG */
 
-struct gpio_keys_polled_dev {
+struct gpio_keys_button_dev {
+       int polled;
        struct delayed_work work;
 
        struct device *dev;
@@ -274,87 +271,91 @@ struct gpio_keys_polled_dev {
        struct gpio_keys_button_data data[0];
 };
 
-static inline int gpio_button_get_value(struct gpio_keys_button *button,
-                         struct gpio_keys_button_data *bdata)
+static int gpio_button_get_value(struct gpio_keys_button_data *bdata)
 {
+       int val;
+
        if (bdata->can_sleep)
-               return !!gpio_get_value_cansleep(button->gpio);
+               val = !!gpio_get_value_cansleep(bdata->b->gpio);
        else
-               return !!gpio_get_value(button->gpio);
+               val = !!gpio_get_value(bdata->b->gpio);
+
+       return val ^ bdata->b->active_low;
 }
 
-static void gpio_keys_polled_check_state(struct gpio_keys_button *button,
-                                        struct gpio_keys_button_data *bdata)
+static void gpio_keys_polled_check_state(struct gpio_keys_button_data *bdata)
 {
-       int state;
+       int state = gpio_button_get_value(bdata);
 
-       state = gpio_button_get_value(button, bdata);
-
-       state = !!(state ^ button->active_low);
        if (state != bdata->last_state) {
-               unsigned int type = button->type ?: EV_KEY;
+               unsigned int type = bdata->b->type ?: EV_KEY;
 
                if (bdata->count < bdata->threshold) {
                        bdata->count++;
                        return;
                }
 
-               button_hotplug_event(bdata, type, button->code, state);
+               if ((bdata->last_state != -1) || (type == EV_SW))
+                       button_hotplug_event(bdata, type, state);
+
                bdata->last_state = state;
        }
 
        bdata->count = 0;
 }
 
-static void gpio_keys_polled_queue_work(struct gpio_keys_polled_dev *bdev)
+static void gpio_keys_polled_queue_work(struct gpio_keys_button_dev *bdev)
 {
        struct gpio_keys_platform_data *pdata = bdev->pdata;
        unsigned long delay = msecs_to_jiffies(pdata->poll_interval);
 
        if (delay >= HZ)
-           delay = round_jiffies_relative(delay);
+               delay = round_jiffies_relative(delay);
        schedule_delayed_work(&bdev->work, delay);
 }
 
 static void gpio_keys_polled_poll(struct work_struct *work)
 {
-       struct gpio_keys_polled_dev *bdev =
-               container_of(work, struct gpio_keys_polled_dev, work.work);
-       struct gpio_keys_platform_data *pdata = bdev->pdata;
+       struct gpio_keys_button_dev *bdev =
+               container_of(work, struct gpio_keys_button_dev, work.work);
        int i;
 
        for (i = 0; i < bdev->pdata->nbuttons; i++) {
                struct gpio_keys_button_data *bdata = &bdev->data[i];
-               gpio_keys_polled_check_state(&pdata->buttons[i], bdata);
+               gpio_keys_polled_check_state(bdata);
        }
        gpio_keys_polled_queue_work(bdev);
 }
 
-static void gpio_keys_polled_open(struct gpio_keys_polled_dev *bdev)
+static void gpio_keys_polled_close(struct gpio_keys_button_dev *bdev)
 {
        struct gpio_keys_platform_data *pdata = bdev->pdata;
-       int i;
 
-       if (pdata->enable)
-               pdata->enable(bdev->dev);
+       cancel_delayed_work_sync(&bdev->work);
 
-       /* report initial state of the buttons */
-       for (i = 0; i < pdata->nbuttons; i++)
-               gpio_keys_polled_check_state(&pdata->buttons[i], &bdev->data[i]);
+       if (pdata->disable)
+               pdata->disable(bdev->dev);
+}
 
-       gpio_keys_polled_queue_work(bdev);
+static irqreturn_t button_handle_irq(int irq, void *_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));
+
+       return IRQ_HANDLED;
 }
 
 #ifdef CONFIG_OF
 static struct gpio_keys_platform_data *
-gpio_keys_polled_get_devtree_pdata(struct device *dev)
+gpio_keys_get_devtree_pdata(struct device *dev)
 {
        struct device_node *node, *pp;
        struct gpio_keys_platform_data *pdata;
        struct gpio_keys_button *button;
        int error;
        int nbuttons;
-       int i;
+       int i = 0;
 
        node = dev->of_node;
        if (!node)
@@ -364,7 +365,7 @@ gpio_keys_polled_get_devtree_pdata(struct device *dev)
        if (nbuttons == 0)
                return NULL;
 
-       pdata = kzalloc(sizeof(*pdata) + nbuttons * (sizeof *button),
+       pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * (sizeof *button),
                GFP_KERNEL);
        if (!pdata) {
                error = -ENOMEM;
@@ -377,7 +378,6 @@ gpio_keys_polled_get_devtree_pdata(struct device *dev)
        pdata->rep = !!of_get_property(node, "autorepeat", NULL);
        of_property_read_u32(node, "poll-interval", &pdata->poll_interval);
 
-       i = 0;
        for_each_child_of_node(node, pp) {
                enum of_gpio_flags flags;
 
@@ -396,7 +396,7 @@ gpio_keys_polled_get_devtree_pdata(struct device *dev)
                        dev_err(dev, "Button without keycode: 0x%x\n",
                                button->gpio);
                        error = -EINVAL;
-                       goto err_free_pdata;
+                       goto err_out;
                }
 
                button->desc = of_get_property(pp, "label", NULL);
@@ -413,17 +413,21 @@ gpio_keys_polled_get_devtree_pdata(struct device *dev)
 
        if (pdata->nbuttons == 0) {
                error = -EINVAL;
-               goto err_free_pdata;
+               goto err_out;
        }
 
        return pdata;
 
-err_free_pdata:
-       kfree(pdata);
 err_out:
        return ERR_PTR(error);
 }
 
+static struct of_device_id gpio_keys_of_match[] = {
+       { .compatible = "gpio-keys", },
+       { },
+};
+MODULE_DEVICE_TABLE(of, gpio_keys_of_match);
+
 static struct of_device_id gpio_keys_polled_of_match[] = {
        { .compatible = "gpio-keys-polled", },
        { },
@@ -433,47 +437,47 @@ MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
 #else
 
 static inline struct gpio_keys_platform_data *
-gpio_keys_polled_get_devtree_pdata(struct device *dev)
+gpio_keys_get_devtree_pdata(struct device *dev)
 {
        return NULL;
 }
 #endif
 
-static void gpio_keys_polled_close(struct gpio_keys_polled_dev *bdev)
-{
-       struct gpio_keys_platform_data *pdata = bdev->pdata;
-
-       cancel_delayed_work_sync(&bdev->work);
-
-       if (pdata->disable)
-               pdata->disable(bdev->dev);
-}
-
-static int gpio_keys_polled_probe(struct platform_device *pdev)
+static int gpio_keys_button_probe(struct platform_device *pdev,
+               struct gpio_keys_button_dev **_bdev, int polled)
 {
        struct gpio_keys_platform_data *pdata = pdev->dev.platform_data;
        struct device *dev = &pdev->dev;
-       struct gpio_keys_polled_dev *bdev;
+       struct gpio_keys_button_dev *bdev;
+       struct gpio_keys_button *buttons;
        int error;
        int i;
 
        if (!pdata) {
-               pdata = gpio_keys_polled_get_devtree_pdata(dev);
+               pdata = gpio_keys_get_devtree_pdata(dev);
                if (IS_ERR(pdata))
                        return PTR_ERR(pdata);
                if (!pdata) {
                        dev_err(dev, "missing platform data\n");
                        return -EINVAL;
                }
+               pdev->dev.platform_data = pdata;
        }
 
-       if (!pdata->poll_interval) {
+       if (polled && !pdata->poll_interval) {
                dev_err(dev, "missing poll_interval value\n");
-               error = -EINVAL;
-               goto err_free_pdata;
+               return -EINVAL;
+       }
+
+       buttons = devm_kzalloc(dev, pdata->nbuttons * sizeof(struct gpio_keys_button),
+                      GFP_KERNEL);
+       if (!buttons) {
+               dev_err(dev, "no memory for button data\n");
+               return -ENOMEM;
        }
+       memcpy(buttons, pdata->buttons, pdata->nbuttons * sizeof(struct gpio_keys_button));
 
-       bdev = kzalloc(sizeof(struct gpio_keys_polled_dev) +
+       bdev = devm_kzalloc(dev, sizeof(struct gpio_keys_button_dev) +
                       pdata->nbuttons * sizeof(struct gpio_keys_button_data),
                       GFP_KERNEL);
        if (!bdev) {
@@ -481,23 +485,24 @@ static int gpio_keys_polled_probe(struct platform_device *pdev)
                return -ENOMEM;
        }
 
+       bdev->polled = polled;
+
        for (i = 0; i < pdata->nbuttons; i++) {
-               struct gpio_keys_button *button = &pdata->buttons[i];
+               struct gpio_keys_button *button = &buttons[i];
                struct gpio_keys_button_data *bdata = &bdev->data[i];
                unsigned int gpio = button->gpio;
 
                if (button->wakeup) {
-                       dev_err(dev, DRV_NAME " does not support wakeup\n");
-                       error = -EINVAL;
-                       goto err_free_gpio;
+                       dev_err(dev, DRV_NAME "does not support wakeup\n");
+                       return -EINVAL;
                }
 
-               error = gpio_request(gpio,
+               error = devm_gpio_request(dev, gpio,
                                     button->desc ? button->desc : DRV_NAME);
                if (error) {
                        dev_err(dev, "unable to claim gpio %u, err=%d\n",
                                gpio, error);
-                       goto err_free_gpio;
+                       return error;
                }
 
                error = gpio_direction_input(gpio);
@@ -505,79 +510,154 @@ static int gpio_keys_polled_probe(struct platform_device *pdev)
                        dev_err(dev,
                                "unable to set direction on gpio %u, err=%d\n",
                                gpio, error);
-                       goto err_free_gpio;
+                       return error;
                }
 
                bdata->can_sleep = gpio_cansleep(gpio);
-               bdata->last_state = gpio_button_get_value(button, bdata);
-               bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
+               bdata->last_state = -1;
+
+               if (bdev->polled)
+                       bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
                                                pdata->poll_interval);
+               else
+                       bdata->threshold = 1;
+
+               bdata->b = &pdata->buttons[i];
        }
 
        bdev->dev = &pdev->dev;
        bdev->pdata = pdata;
        platform_set_drvdata(pdev, bdev);
 
-       INIT_DELAYED_WORK(&bdev->work, gpio_keys_polled_poll);
-
-       gpio_keys_polled_open(bdev);
+       *_bdev = bdev;
 
        return 0;
+}
+
+static int gpio_keys_probe(struct platform_device *pdev)
+{
+       struct gpio_keys_platform_data *pdata;
+       struct gpio_keys_button_dev *bdev;
+       int ret, i;
 
-err_free_gpio:
-       while (--i >= 0)
-               gpio_free(pdata->buttons[i].gpio);
 
-       kfree(bdev);
-       platform_set_drvdata(pdev, NULL);
+       ret = gpio_keys_button_probe(pdev, &bdev, 0);
 
-err_free_pdata:
-       /* If we have no platform_data, we allocated pdata dynamically.  */
-       if (!dev_get_platdata(&pdev->dev))
-               kfree(pdata);
+       if (ret)
+               return ret;
+
+       pdata = pdev->dev.platform_data;
+       for (i = 0; i < pdata->nbuttons; i++) {
+               struct gpio_keys_button *button = &pdata->buttons[i];
+               struct gpio_keys_button_data *bdata = &bdev->data[i];
+
+               if (bdata->can_sleep) {
+                       dev_err(&pdev->dev, "skipping gpio:%d, it can sleep\n", button->gpio);
+                       continue;
+               }
+               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;
+               }
+               ret = devm_request_irq(&pdev->dev, button->irq, button_handle_irq,
+                                       IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+                                       dev_name(&pdev->dev), bdata);
+               if (ret)
+                       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);
+
+               if (bdata->b->type == EV_SW)
+                       button_hotplug_event(bdata, EV_SW, gpio_button_get_value(bdata));
+       }
 
-       return error;
+       return 0;
 }
 
-static int gpio_keys_polled_remove(struct platform_device *pdev)
+static int gpio_keys_polled_probe(struct platform_device *pdev)
 {
-       struct gpio_keys_polled_dev *bdev = platform_get_drvdata(pdev);
-       struct gpio_keys_platform_data *pdata = bdev->pdata;
-       int i = pdata->nbuttons;
+       struct gpio_keys_platform_data *pdata;
+       struct gpio_keys_button_dev *bdev;
+       int ret;
+       int i;
+
+       ret = gpio_keys_button_probe(pdev, &bdev, 1);
+
+       if (ret)
+               return ret;
+
+       INIT_DELAYED_WORK(&bdev->work, gpio_keys_polled_poll);
+
+       pdata = bdev->pdata;
 
-       gpio_keys_polled_close(bdev);
+       if (pdata->enable)
+               pdata->enable(bdev->dev);
 
-       while (--i >= 0)
-               gpio_free(pdata->buttons[i].gpio);
+       for (i = 0; i < pdata->nbuttons; i++)
+               gpio_keys_polled_check_state(&bdev->data[i]);
+
+       gpio_keys_polled_queue_work(bdev);
+
+       return ret;
+}
+
+static int gpio_keys_remove(struct platform_device *pdev)
+{
+       struct gpio_keys_button_dev *bdev = platform_get_drvdata(pdev);
 
-       kfree(bdev);
        platform_set_drvdata(pdev, NULL);
 
+       if (bdev->polled)
+               gpio_keys_polled_close(bdev);
+
        return 0;
 }
 
+static struct platform_driver gpio_keys_driver = {
+       .probe  = gpio_keys_probe,
+       .remove = gpio_keys_remove,
+       .driver = {
+               .name   = "gpio-keys",
+               .owner  = THIS_MODULE,
+               .of_match_table = of_match_ptr(gpio_keys_of_match),
+       },
+};
+
 static struct platform_driver gpio_keys_polled_driver = {
        .probe  = gpio_keys_polled_probe,
-       .remove = gpio_keys_polled_remove,
+       .remove = gpio_keys_remove,
        .driver = {
-               .name   = DRV_NAME,
+               .name   = "gpio-keys-polled",
                .owner  = THIS_MODULE,
                .of_match_table = of_match_ptr(gpio_keys_polled_of_match),
        },
 };
 
-static int __init gpio_keys_polled_init(void)
+static int __init gpio_button_init(void)
 {
-       return platform_driver_register(&gpio_keys_polled_driver);
+       int ret;
+
+       ret = platform_driver_register(&gpio_keys_driver);
+       if (ret)
+               return ret;
+
+       ret = platform_driver_register(&gpio_keys_polled_driver);
+       if (ret)
+               platform_driver_unregister(&gpio_keys_driver);
+
+       return ret;
 }
 
-static void __exit gpio_keys_polled_exit(void)
+static void __exit gpio_button_exit(void)
 {
+       platform_driver_unregister(&gpio_keys_driver);
        platform_driver_unregister(&gpio_keys_polled_driver);
 }
 
-module_init(gpio_keys_polled_init);
-module_exit(gpio_keys_polled_exit);
+module_init(gpio_button_init);
+module_exit(gpio_button_exit);
 
 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");