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authorJames <>2015-11-04 11:49:21 +0000
committerJames <>2015-11-04 11:49:21 +0000
commit716ca530e1c4515d8683c9d5be3d56b301758b66 (patch)
tree700eb5bcc1a462a5f21dcec15ce7c97ecfefa772 /package/kernel/gpio-button-hotplug
downloadtrunk-47381-master.tar.gz
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Diffstat (limited to 'package/kernel/gpio-button-hotplug')
-rw-r--r--package/kernel/gpio-button-hotplug/Makefile50
-rw-r--r--package/kernel/gpio-button-hotplug/src/Makefile1
-rw-r--r--package/kernel/gpio-button-hotplug/src/gpio-button-hotplug.c670
3 files changed, 721 insertions, 0 deletions
diff --git a/package/kernel/gpio-button-hotplug/Makefile b/package/kernel/gpio-button-hotplug/Makefile
new file mode 100644
index 0000000..c2fdaec
--- /dev/null
+++ b/package/kernel/gpio-button-hotplug/Makefile
@@ -0,0 +1,50 @@
+#
+# Copyright (C) 2008-2012 OpenWrt.org
+#
+# This is free software, licensed under the GNU General Public License v2.
+# See /LICENSE for more information.
+#
+
+include $(TOPDIR)/rules.mk
+include $(INCLUDE_DIR)/kernel.mk
+
+PKG_NAME:=gpio-button-hotplug
+PKG_RELEASE:=1
+
+include $(INCLUDE_DIR)/package.mk
+
+define KernelPackage/gpio-button-hotplug
+ SUBMENU:=Other modules
+ TITLE:=Simple GPIO Button Hotplug driver
+ FILES:=$(PKG_BUILD_DIR)/gpio-button-hotplug.ko
+ AUTOLOAD:=$(call AutoLoad,30,gpio-button-hotplug,1)
+ KCONFIG:=
+endef
+
+define KernelPackage/gpio-button-hotplug/description
+ This is a replacement for the following in-kernel drivers:
+ 1) gpio_keys (KEYBOARD_GPIO)
+ 2) gpio_keys_polled (KEYBOARD_GPIO_POLLED)
+
+ Instead of generating input events (like in-kernel drivers do) it generates
+ uevent-s and broadcasts them. This allows disabling input subsystem which is
+ an overkill for OpenWrt simple needs.
+endef
+
+MAKE_OPTS:= \
+ ARCH="$(LINUX_KARCH)" \
+ CROSS_COMPILE="$(TARGET_CROSS)" \
+ SUBDIRS="$(PKG_BUILD_DIR)"
+
+define Build/Prepare
+ mkdir -p $(PKG_BUILD_DIR)
+ $(CP) ./src/* $(PKG_BUILD_DIR)/
+endef
+
+define Build/Compile
+ $(MAKE) -C "$(LINUX_DIR)" \
+ $(MAKE_OPTS) \
+ modules
+endef
+
+$(eval $(call KernelPackage,gpio-button-hotplug))
diff --git a/package/kernel/gpio-button-hotplug/src/Makefile b/package/kernel/gpio-button-hotplug/src/Makefile
new file mode 100644
index 0000000..e968865
--- /dev/null
+++ b/package/kernel/gpio-button-hotplug/src/Makefile
@@ -0,0 +1 @@
+obj-m += gpio-button-hotplug.o
diff --git a/package/kernel/gpio-button-hotplug/src/gpio-button-hotplug.c b/package/kernel/gpio-button-hotplug/src/gpio-button-hotplug.c
new file mode 100644
index 0000000..029a388
--- /dev/null
+++ b/package/kernel/gpio-button-hotplug/src/gpio-button-hotplug.c
@@ -0,0 +1,670 @@
+/*
+ * GPIO Button Hotplug driver
+ *
+ * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2008-2010 Gabor Juhos <juhosg@openwrt.org>
+ *
+ * Based on the diag.c - GPIO interface driver for Broadcom boards
+ * Copyright (C) 2006 Mike Baker <mbm@openwrt.org>,
+ * Copyright (C) 2006-2007 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2008 Andy Boyett <agb@openwrt.org>
+ *
+ * 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 published
+ * by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/kmod.h>
+
+#include <linux/workqueue.h>
+#include <linux/skbuff.h>
+#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"
+
+#define BH_SKB_SIZE 2048
+
+#define PFX DRV_NAME ": "
+
+#undef BH_DEBUG
+
+#ifdef BH_DEBUG
+#define BH_DBG(fmt, args...) printk(KERN_DEBUG "%s: " fmt, DRV_NAME, ##args )
+#else
+#define BH_DBG(fmt, args...) do {} while (0)
+#endif
+
+#define BH_ERR(fmt, args...) printk(KERN_ERR "%s: " fmt, DRV_NAME, ##args )
+
+struct bh_priv {
+ unsigned long seen;
+};
+
+struct bh_event {
+ const char *name;
+ unsigned int type;
+ char *action;
+ unsigned long seen;
+
+ struct sk_buff *skb;
+ struct work_struct work;
+};
+
+struct bh_map {
+ unsigned int code;
+ const char *name;
+};
+
+struct gpio_keys_button_data {
+ struct delayed_work work;
+ struct bh_priv bh;
+ int last_state;
+ int count;
+ int threshold;
+ int can_sleep;
+ struct gpio_keys_button *b;
+};
+
+extern u64 uevent_next_seqnum(void);
+
+#define BH_MAP(_code, _name) \
+ { \
+ .code = (_code), \
+ .name = (_name), \
+ }
+
+static struct bh_map button_map[] = {
+ BH_MAP(BTN_0, "BTN_0"),
+ BH_MAP(BTN_1, "BTN_1"),
+ BH_MAP(BTN_2, "BTN_2"),
+ BH_MAP(BTN_3, "BTN_3"),
+ BH_MAP(BTN_4, "BTN_4"),
+ BH_MAP(BTN_5, "BTN_5"),
+ BH_MAP(BTN_6, "BTN_6"),
+ 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"),
+ BH_MAP(KEY_WIMAX, "wwan"),
+};
+
+/* -------------------------------------------------------------------------*/
+
+static __printf(3, 4)
+int bh_event_add_var(struct bh_event *event, int argv, const char *format, ...)
+{
+ static char buf[128];
+ char *s;
+ va_list args;
+ int len;
+
+ if (argv)
+ return 0;
+
+ va_start(args, format);
+ len = vsnprintf(buf, sizeof(buf), format, args);
+ va_end(args);
+
+ if (len >= sizeof(buf)) {
+ WARN(1, "buffer size too small");
+ return -ENOMEM;
+ }
+
+ s = skb_put(event->skb, len + 1);
+ strcpy(s, buf);
+
+ BH_DBG("added variable '%s'\n", s);
+
+ return 0;
+}
+
+static int button_hotplug_fill_event(struct bh_event *event)
+{
+ int ret;
+
+ ret = bh_event_add_var(event, 0, "HOME=%s", "/");
+ if (ret)
+ return ret;
+
+ ret = bh_event_add_var(event, 0, "PATH=%s",
+ "/sbin:/bin:/usr/sbin:/usr/bin");
+ if (ret)
+ return ret;
+
+ ret = bh_event_add_var(event, 0, "SUBSYSTEM=%s", "button");
+ if (ret)
+ return ret;
+
+ ret = bh_event_add_var(event, 0, "ACTION=%s", event->action);
+ if (ret)
+ return ret;
+
+ ret = bh_event_add_var(event, 0, "BUTTON=%s", event->name);
+ 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;
+
+ ret = bh_event_add_var(event, 0, "SEQNUM=%llu", uevent_next_seqnum());
+
+ return ret;
+}
+
+static void button_hotplug_work(struct work_struct *work)
+{
+ struct bh_event *event = container_of(work, struct bh_event, work);
+ int ret = 0;
+
+ event->skb = alloc_skb(BH_SKB_SIZE, GFP_KERNEL);
+ if (!event->skb)
+ goto out_free_event;
+
+ ret = bh_event_add_var(event, 0, "%s@", event->action);
+ if (ret)
+ goto out_free_skb;
+
+ ret = button_hotplug_fill_event(event);
+ if (ret)
+ goto out_free_skb;
+
+ NETLINK_CB(event->skb).dst_group = 1;
+ broadcast_uevent(event->skb, 0, 1, GFP_KERNEL);
+
+ out_free_skb:
+ if (ret) {
+ BH_ERR("work error %d\n", ret);
+ kfree_skb(event->skb);
+ }
+ out_free_event:
+ kfree(event);
+}
+
+static int button_hotplug_create_event(const char *name, unsigned int type,
+ unsigned long seen, int pressed)
+{
+ struct bh_event *event;
+
+ BH_DBG("create event, name=%s, seen=%lu, pressed=%d\n",
+ name, seen, pressed);
+
+ event = kzalloc(sizeof(*event), GFP_KERNEL);
+ if (!event)
+ return -ENOMEM;
+
+ event->name = name;
+ event->type = type;
+ event->seen = seen;
+ event->action = pressed ? "pressed" : "released";
+
+ INIT_WORK(&event->work, (void *)(void *)button_hotplug_work);
+ schedule_work(&event->work);
+
+ return 0;
+}
+
+/* -------------------------------------------------------------------------*/
+
+static int button_get_index(unsigned int code)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(button_map); i++)
+ if (button_map[i].code == code)
+ return i;
+
+ return -1;
+}
+
+static void button_hotplug_event(struct gpio_keys_button_data *data,
+ 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, data->b->code, value);
+
+ if ((type != EV_KEY) && (type != EV_SW))
+ return;
+
+ btn = button_get_index(data->b->code);
+ if (btn < 0)
+ return;
+
+ button_hotplug_create_event(button_map[btn].name, type,
+ (seen - priv->seen) / HZ, value);
+ priv->seen = seen;
+}
+
+struct gpio_keys_button_dev {
+ int polled;
+ struct delayed_work work;
+
+ struct device *dev;
+ struct gpio_keys_platform_data *pdata;
+ struct gpio_keys_button_data data[0];
+};
+
+static int gpio_button_get_value(struct gpio_keys_button_data *bdata)
+{
+ int val;
+
+ if (bdata->can_sleep)
+ val = !!gpio_get_value_cansleep(bdata->b->gpio);
+ else
+ val = !!gpio_get_value(bdata->b->gpio);
+
+ return val ^ bdata->b->active_low;
+}
+
+static void gpio_keys_polled_check_state(struct gpio_keys_button_data *bdata)
+{
+ int state = gpio_button_get_value(bdata);
+
+ if (state != bdata->last_state) {
+ unsigned int type = bdata->b->type ?: EV_KEY;
+
+ if (bdata->count < bdata->threshold) {
+ bdata->count++;
+ return;
+ }
+
+ 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_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);
+ schedule_delayed_work(&bdev->work, delay);
+}
+
+static void gpio_keys_polled_poll(struct work_struct *work)
+{
+ 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(bdata);
+ }
+ gpio_keys_polled_queue_work(bdev);
+}
+
+static void gpio_keys_polled_close(struct gpio_keys_button_dev *bdev)
+{
+ struct gpio_keys_platform_data *pdata = bdev->pdata;
+
+ cancel_delayed_work_sync(&bdev->work);
+
+ if (pdata->disable)
+ pdata->disable(bdev->dev);
+}
+
+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_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 = 0;
+
+ node = dev->of_node;
+ if (!node)
+ return NULL;
+
+ nbuttons = of_get_child_count(node);
+ if (nbuttons == 0)
+ return NULL;
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata) + nbuttons * (sizeof *button),
+ GFP_KERNEL);
+ if (!pdata) {
+ error = -ENOMEM;
+ goto err_out;
+ }
+
+ pdata->buttons = (struct gpio_keys_button *)(pdata + 1);
+ pdata->nbuttons = nbuttons;
+
+ pdata->rep = !!of_get_property(node, "autorepeat", NULL);
+ of_property_read_u32(node, "poll-interval", &pdata->poll_interval);
+
+ for_each_child_of_node(node, pp) {
+ enum of_gpio_flags flags;
+
+ if (!of_find_property(pp, "gpios", NULL)) {
+ pdata->nbuttons--;
+ dev_warn(dev, "Found button without gpios\n");
+ continue;
+ }
+
+ button = &pdata->buttons[i++];
+
+ button->gpio = of_get_gpio_flags(pp, 0, &flags);
+ if (button->gpio < 0) {
+ error = button->gpio;
+ if (error != -ENOENT) {
+ if (error != -EPROBE_DEFER)
+ dev_err(dev,
+ "Failed to get gpio flags, error: %d\n",
+ error);
+ return ERR_PTR(error);
+ }
+ } else {
+ button->active_low = flags & OF_GPIO_ACTIVE_LOW;
+ }
+
+ if (of_property_read_u32(pp, "linux,code", &button->code)) {
+ dev_err(dev, "Button without keycode: 0x%x\n",
+ button->gpio);
+ error = -EINVAL;
+ goto err_out;
+ }
+
+ button->desc = of_get_property(pp, "label", NULL);
+
+ if (of_property_read_u32(pp, "linux,input-type", &button->type))
+ button->type = EV_KEY;
+
+ button->wakeup = !!of_get_property(pp, "gpio-key,wakeup", NULL);
+
+ if (of_property_read_u32(pp, "debounce-interval",
+ &button->debounce_interval))
+ button->debounce_interval = 5;
+ }
+
+ if (pdata->nbuttons == 0) {
+ error = -EINVAL;
+ goto err_out;
+ }
+
+ return 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", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);
+
+#else
+
+static inline struct gpio_keys_platform_data *
+gpio_keys_get_devtree_pdata(struct device *dev)
+{
+ return NULL;
+}
+#endif
+
+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_button_dev *bdev;
+ struct gpio_keys_button *buttons;
+ int error;
+ int i;
+
+ if (!pdata) {
+ 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 (polled && !pdata->poll_interval) {
+ dev_err(dev, "missing poll_interval value\n");
+ 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 = devm_kzalloc(dev, sizeof(struct gpio_keys_button_dev) +
+ pdata->nbuttons * sizeof(struct gpio_keys_button_data),
+ GFP_KERNEL);
+ if (!bdev) {
+ dev_err(dev, "no memory for private data\n");
+ return -ENOMEM;
+ }
+
+ bdev->polled = polled;
+
+ for (i = 0; i < pdata->nbuttons; 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");
+ return -EINVAL;
+ }
+
+ 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);
+ return error;
+ }
+
+ error = gpio_direction_input(gpio);
+ if (error) {
+ dev_err(dev,
+ "unable to set direction on gpio %u, err=%d\n",
+ gpio, error);
+ return error;
+ }
+
+ bdata->can_sleep = gpio_cansleep(gpio);
+ 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);
+
+ *_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;
+
+
+ ret = gpio_keys_button_probe(pdev, &bdev, 0);
+
+ 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 0;
+}
+
+static int gpio_keys_polled_probe(struct platform_device *pdev)
+{
+ 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;
+
+ if (pdata->enable)
+ pdata->enable(bdev->dev);
+
+ 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);
+
+ 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_remove,
+ .driver = {
+ .name = "gpio-keys-polled",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(gpio_keys_polled_of_match),
+ },
+};
+
+static int __init gpio_button_init(void)
+{
+ 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_button_exit(void)
+{
+ platform_driver_unregister(&gpio_keys_driver);
+ platform_driver_unregister(&gpio_keys_polled_driver);
+}
+
+module_init(gpio_button_init);
+module_exit(gpio_button_exit);
+
+MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
+MODULE_AUTHOR("Felix Fietkau <nbd@openwrt.org>");
+MODULE_DESCRIPTION("Polled GPIO Buttons hotplug driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRV_NAME);