HID: wacom: leds: handle the switch of the LEDs directly in the kernel

The EKR switches the LED directly, and there is no point in having
userspace handling the switch it self when it's easy enough to do
in the kernel.

The other benefit is that now userspace does not need to have root access
to the LED but need only to read them with user privileges.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 78ac4811bd3c0c0683e62bfe424c43c0fba4c8a9..bdacb552f0a33df59161266fa4adcd4602a39d99 100644 (file)
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -862,6 +862,7 @@ config HID_WACOM
        select POWER_SUPPLY
        select NEW_LEDS
        select LEDS_CLASS
+       select LEDS_TRIGGERS
        help
          Say Y here if you want to use the USB or BT version of the Wacom Intuos
          or Graphire tablet.

diff --git a/drivers/hid/wacom.h b/drivers/hid/wacom.h
index 9159dd3e4b902490e46f04144751f91e3e3e5c78..8f8a16243f0745880666d9aa45c6b3a8f0e67763 100644 (file)
--- a/drivers/hid/wacom.h
+++ b/drivers/hid/wacom.h
@@ -216,4 +216,8 @@ int wacom_wac_event(struct hid_device *hdev, struct hid_field *field,
                struct hid_usage *usage, __s32 value);
 void wacom_wac_report(struct hid_device *hdev, struct hid_report *report);
 void wacom_battery_work(struct work_struct *work);
+enum led_brightness wacom_leds_brightness_get(struct wacom_led *led);
+struct wacom_led *wacom_led_find(struct wacom *wacom, unsigned int group,
+                                unsigned int id);
+struct wacom_led *wacom_led_next(struct wacom *wacom, struct wacom_led *cur);
 #endif

diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
index 3a651e28877609fcfecb0d96d8130c48567f2cfb..7e83352adbde8e9e32ba97187b0edeaedac2a9f0 100644 (file)
--- a/drivers/hid/wacom_sys.c
+++ b/drivers/hid/wacom_sys.c
@@ -969,7 +969,7 @@ static int wacom_devm_sysfs_create_group(struct wacom *wacom,
                                               group);
 }
 
-static enum led_brightness wacom_leds_brightness_get(struct wacom_led *led)
+enum led_brightness wacom_leds_brightness_get(struct wacom_led *led)
 {
        struct wacom *wacom = led->wacom;
 
@@ -1042,6 +1042,17 @@ static int wacom_led_register_one(struct device *dev, struct wacom *wacom,
        if (!name)
                return -ENOMEM;
 
+       if (!read_only) {
+               led->trigger.name = name;
+               error = devm_led_trigger_register(dev, &led->trigger);
+               if (error) {
+                       hid_err(wacom->hdev,
+                               "failed to register LED trigger %s: %d\n",
+                               led->cdev.name, error);
+                       return error;
+               }
+       }
+
        led->group = group;
        led->id = id;
        led->wacom = wacom;
@@ -1051,10 +1062,12 @@ static int wacom_led_register_one(struct device *dev, struct wacom *wacom,
        led->cdev.max_brightness = LED_FULL;
        led->cdev.flags = LED_HW_PLUGGABLE;
        led->cdev.brightness_get = __wacom_led_brightness_get;
-       if (!read_only)
+       if (!read_only) {
                led->cdev.brightness_set_blocking = wacom_led_brightness_set;
-       else
+               led->cdev.default_trigger = led->cdev.name;
+       } else {
                led->cdev.brightness_set = wacom_led_readonly_brightness_set;
+       }
 
        error = devm_led_classdev_register(dev, &led->cdev);
        if (error) {
@@ -1131,6 +1144,50 @@ err:
        return error;
 }
 
+struct wacom_led *wacom_led_find(struct wacom *wacom, unsigned int group_id,
+                                unsigned int id)
+{
+       struct wacom_group_leds *group;
+
+       if (group_id >= wacom->led.count)
+               return NULL;
+
+       group = &wacom->led.groups[group_id];
+
+       if (!group->leds)
+               return NULL;
+
+       id %= group->count;
+
+       return &group->leds[id];
+}
+
+/**
+ * wacom_led_next: gives the next available led with a wacom trigger.
+ *
+ * returns the next available struct wacom_led which has its default trigger
+ * or the current one if none is available.
+ */
+struct wacom_led *wacom_led_next(struct wacom *wacom, struct wacom_led *cur)
+{
+       struct wacom_led *next_led;
+       int group, next;
+
+       if (!wacom || !cur)
+               return NULL;
+
+       group = cur->group;
+       next = cur->id;
+
+       do {
+               next_led = wacom_led_find(wacom, group, ++next);
+               if (!next_led || next_led == cur)
+                       return next_led;
+       } while (next_led->cdev.trigger != &next_led->trigger);
+
+       return next_led;
+}
+
 static void wacom_led_groups_release(void *data)
 {
        struct wacom *wacom = data;

diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index 1c882bb70f140195fb46eb1d7b74fed00b7900df..00e0c80be6d50f9b7213729e70f628d2cabe7547 100644 (file)
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c
@@ -2763,11 +2763,64 @@ static void wacom_setup_numbered_buttons(struct input_dev *input_dev,
                __set_bit(BTN_BASE + (i-16), input_dev->keybit);
 }
 
+static bool wacom_is_led_toggled(struct wacom *wacom, int button_count,
+                                int mask, int group)
+{
+       int button_per_group;
+
+       button_per_group = button_count/wacom->led.count;
+
+       return mask & (1 << (group * button_per_group));
+}
+
+static void wacom_update_led(struct wacom *wacom, int button_count, int mask,
+                            int group)
+{
+       struct wacom_led *led, *next_led;
+       int cur;
+       bool pressed;
+
+       pressed = wacom_is_led_toggled(wacom, button_count, mask, group);
+       cur = wacom->led.groups[group].select;
+
+       led = wacom_led_find(wacom, group, cur);
+       if (!led) {
+               hid_err(wacom->hdev, "can't find current LED %d in group %d\n",
+                       cur, group);
+               return;
+       }
+
+       if (!pressed) {
+               led->held = false;
+               return;
+       }
+
+       if (led->held && pressed)
+               return;
+
+       next_led = wacom_led_next(wacom, led);
+       if (!next_led) {
+               hid_err(wacom->hdev, "can't find next LED in group %d\n",
+                       group);
+               return;
+       }
+       if (next_led == led)
+               return;
+
+       next_led->held = true;
+       led_trigger_event(&next_led->trigger,
+                         wacom_leds_brightness_get(next_led));
+}
+
 static void wacom_report_numbered_buttons(struct input_dev *input_dev,
                                int button_count, int mask)
 {
+       struct wacom *wacom = input_get_drvdata(input_dev);
        int i;
 
+       for (i = 0; i < wacom->led.count; i++)
+               wacom_update_led(wacom,  button_count, mask, i);
+
        for (i = 0; i < button_count && i < 10; i++)
                input_report_key(input_dev, BTN_0 + i, mask & (1 << i));
        for (i = 10; i < button_count && i < 16; i++)