HID: wiimote: convert BATTERY to module

This introduces a new sub-device module for the BATTERY handlers. It
moves the whole power_supply battery handling over to wiimote-modules.

This doesn't change any semantics or ABI but only converts the battery
handling into a sub-device module.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

3 files changed, 104 insertions, 76 deletions

diff --git a/drivers/hid/hid-wiimote-core.c b/drivers/hid/hid-wiimote-core.c
index 6ada22606707..bb1b3e3f4550 100644
--- a/drivers/hid/hid-wiimote-core.c
+++ b/drivers/hid/hid-wiimote-core.c
@@ -17,16 +17,10 @@
 #include <linux/leds.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
-#include <linux/power_supply.h>
 #include <linux/spinlock.h>
 #include "hid-ids.h"
 #include "hid-wiimote.h"
 
-static enum power_supply_property wiimote_battery_props[] = {
-        POWER_SUPPLY_PROP_CAPACITY,
-        POWER_SUPPLY_PROP_SCOPE,
-};
-
 /* output queue handling */
 
 static int wiimote_hid_send(struct hid_device *hdev, __u8 *buffer,
@@ -232,7 +226,7 @@ void wiiproto_req_drm(struct wiimote_data *wdata, __u8 drm)
         wiimote_queue(wdata, cmd, sizeof(cmd));
 }
 
-static void wiiproto_req_status(struct wiimote_data *wdata)
+void wiiproto_req_status(struct wiimote_data *wdata)
 {
         __u8 cmd[2];
 
@@ -423,48 +417,6 @@ static __u8 wiimote_cmd_read_ext(struct wiimote_data *wdata)
         return WIIMOTE_EXT_UNKNOWN;
 }
 
-static int wiimote_battery_get_property(struct power_supply *psy,
-                                                enum power_supply_property psp,
-                                                union power_supply_propval *val)
-{
-        struct wiimote_data *wdata = container_of(psy,
-                                                struct wiimote_data, battery);
-        int ret = 0, state;
-        unsigned long flags;
-
-        if (psp == POWER_SUPPLY_PROP_SCOPE) {
-                val->intval = POWER_SUPPLY_SCOPE_DEVICE;
-                return 0;
-        }
-
-        ret = wiimote_cmd_acquire(wdata);
-        if (ret)
-                return ret;
-
-        spin_lock_irqsave(&wdata->state.lock, flags);
-        wiimote_cmd_set(wdata, WIIPROTO_REQ_SREQ, 0);
-        wiiproto_req_status(wdata);
-        spin_unlock_irqrestore(&wdata->state.lock, flags);
-
-        wiimote_cmd_wait(wdata);
-        wiimote_cmd_release(wdata);
-
-        spin_lock_irqsave(&wdata->state.lock, flags);
-        state = wdata->state.cmd_battery;
-        spin_unlock_irqrestore(&wdata->state.lock, flags);
-
-        switch (psp) {
-                case POWER_SUPPLY_PROP_CAPACITY:
-                        val->intval = state * 100 / 255;
-                        break;
-                default:
-                        ret = -EINVAL;
-                        break;
-        }
-
-        return ret;
-}
-
 static int wiimote_init_ir(struct wiimote_data *wdata, __u16 mode)
 {
         int ret;
@@ -673,16 +625,19 @@ static const __u8 * const wiimote_devtype_mods[WIIMOTE_DEV_NUM] = {
         [WIIMOTE_DEV_GENERIC] = (const __u8[]){
                 WIIMOD_KEYS,
                 WIIMOD_RUMBLE,
+                WIIMOD_BATTERY,
                 WIIMOD_NULL,
         },
         [WIIMOTE_DEV_GEN10] = (const __u8[]){
                 WIIMOD_KEYS,
                 WIIMOD_RUMBLE,
+                WIIMOD_BATTERY,
                 WIIMOD_NULL,
         },
         [WIIMOTE_DEV_GEN20] = (const __u8[]){
                 WIIMOD_KEYS,
                 WIIMOD_RUMBLE,
+                WIIMOD_BATTERY,
                 WIIMOD_NULL,
         },
 };
@@ -1349,8 +1304,6 @@ static void wiimote_destroy(struct wiimote_data *wdata)
 
         cancel_work_sync(&wdata->init_worker);
         wiimote_modules_unload(wdata);
-        power_supply_unregister(&wdata->battery);
-        kfree(wdata->battery.name);
         input_unregister_device(wdata->accel);
         input_unregister_device(wdata->ir);
         cancel_work_sync(&wdata->queue.worker);
@@ -1404,26 +1357,6 @@ static int wiimote_hid_probe(struct hid_device *hdev,
                 goto err_ir;
         }
 
-        wdata->battery.properties = wiimote_battery_props;
-        wdata->battery.num_properties = ARRAY_SIZE(wiimote_battery_props);
-        wdata->battery.get_property = wiimote_battery_get_property;
-        wdata->battery.type = POWER_SUPPLY_TYPE_BATTERY;
-        wdata->battery.use_for_apm = 0;
-        wdata->battery.name = kasprintf(GFP_KERNEL, "wiimote_battery_%s",
-                                        wdata->hdev->uniq);
-        if (!wdata->battery.name) {
-                ret = -ENOMEM;
-                goto err_battery_name;
-        }
-
-        ret = power_supply_register(&wdata->hdev->dev, &wdata->battery);
-        if (ret) {
-                hid_err(hdev, "Cannot register battery device\n");
-                goto err_battery;
-        }
-
-        power_supply_powers(&wdata->battery, &hdev->dev);
-
         ret = wiimote_leds_create(wdata);
         if (ret)
                 goto err_free;
@@ -1452,11 +1385,6 @@ err_free:
         wiimote_destroy(wdata);
         return ret;
 
-err_battery:
-        kfree(wdata->battery.name);
-err_battery_name:
-        input_unregister_device(wdata->ir);
-        wdata->ir = NULL;
 err_ir:
         input_unregister_device(wdata->accel);
         wdata->accel = NULL;
diff --git a/drivers/hid/hid-wiimote-modules.c b/drivers/hid/hid-wiimote-modules.c
index 616f24024f77..4cbbbe651ba5 100644
--- a/drivers/hid/hid-wiimote-modules.c
+++ b/drivers/hid/hid-wiimote-modules.c
@@ -171,9 +171,107 @@ static const struct wiimod_ops wiimod_rumble = {
         .remove = wiimod_rumble_remove,
 };
 
+/*
+ * Battery
+ * 1 byte of battery capacity information is sent along every protocol status
+ * report. The wiimote core caches it but we try to update it on every
+ * user-space request.
+ * This is supported by nearly every device so it's almost always enabled.
+ */
+
+static enum power_supply_property wiimod_battery_props[] = {
+        POWER_SUPPLY_PROP_CAPACITY,
+        POWER_SUPPLY_PROP_SCOPE,
+};
+
+static int wiimod_battery_get_property(struct power_supply *psy,
+                                       enum power_supply_property psp,
+                                       union power_supply_propval *val)
+{
+        struct wiimote_data *wdata = container_of(psy, struct wiimote_data,
+                                                  battery);
+        int ret = 0, state;
+        unsigned long flags;
+
+        if (psp == POWER_SUPPLY_PROP_SCOPE) {
+                val->intval = POWER_SUPPLY_SCOPE_DEVICE;
+                return 0;
+        } else if (psp != POWER_SUPPLY_PROP_CAPACITY) {
+                return -EINVAL;
+        }
+
+        ret = wiimote_cmd_acquire(wdata);
+        if (ret)
+                return ret;
+
+        spin_lock_irqsave(&wdata->state.lock, flags);
+        wiimote_cmd_set(wdata, WIIPROTO_REQ_SREQ, 0);
+        wiiproto_req_status(wdata);
+        spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+        wiimote_cmd_wait(wdata);
+        wiimote_cmd_release(wdata);
+
+        spin_lock_irqsave(&wdata->state.lock, flags);
+        state = wdata->state.cmd_battery;
+        spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+        val->intval = state * 100 / 255;
+        return ret;
+}
+
+static int wiimod_battery_probe(const struct wiimod_ops *ops,
+                                struct wiimote_data *wdata)
+{
+        int ret;
+
+        wdata->battery.properties = wiimod_battery_props;
+        wdata->battery.num_properties = ARRAY_SIZE(wiimod_battery_props);
+        wdata->battery.get_property = wiimod_battery_get_property;
+        wdata->battery.type = POWER_SUPPLY_TYPE_BATTERY;
+        wdata->battery.use_for_apm = 0;
+        wdata->battery.name = kasprintf(GFP_KERNEL, "wiimote_battery_%s",
+                                        wdata->hdev->uniq);
+        if (!wdata->battery.name)
+                return -ENOMEM;
+
+        ret = power_supply_register(&wdata->hdev->dev, &wdata->battery);
+        if (ret) {
+                hid_err(wdata->hdev, "cannot register battery device\n");
+                goto err_free;
+        }
+
+        power_supply_powers(&wdata->battery, &wdata->hdev->dev);
+        return 0;
+
+err_free:
+        kfree(wdata->battery.name);
+        wdata->battery.name = NULL;
+        return ret;
+}
+
+static void wiimod_battery_remove(const struct wiimod_ops *ops,
+                                  struct wiimote_data *wdata)
+{
+        if (!wdata->battery.name)
+                return;
+
+        power_supply_unregister(&wdata->battery);
+        kfree(wdata->battery.name);
+        wdata->battery.name = NULL;
+}
+
+static const struct wiimod_ops wiimod_battery = {
+        .flags = 0,
+        .arg = 0,
+        .probe = wiimod_battery_probe,
+        .remove = wiimod_battery_remove,
+};
+
 /* module table */
 
 const struct wiimod_ops *wiimod_table[WIIMOD_NUM] = {
         [WIIMOD_KEYS] = &wiimod_keys,
         [WIIMOD_RUMBLE] = &wiimod_rumble,
+        [WIIMOD_BATTERY] = &wiimod_battery,
 };
diff --git a/drivers/hid/hid-wiimote.h b/drivers/hid/hid-wiimote.h
index 93c48fbef7a5..4151514fcd2e 100644
--- a/drivers/hid/hid-wiimote.h
+++ b/drivers/hid/hid-wiimote.h
@@ -128,6 +128,7 @@ struct wiimote_data {
 enum wiimod_module {
         WIIMOD_KEYS,
         WIIMOD_RUMBLE,
+        WIIMOD_BATTERY,
         WIIMOD_NUM,
         WIIMOD_NULL = WIIMOD_NUM,
 };
@@ -184,6 +185,7 @@ enum wiiproto_reqs {
 
 extern void wiiproto_req_drm(struct wiimote_data *wdata, __u8 drm);
 extern void wiiproto_req_rumble(struct wiimote_data *wdata, __u8 rumble);
+extern void wiiproto_req_status(struct wiimote_data *wdata);
 extern int wiimote_cmd_write(struct wiimote_data *wdata, __u32 offset,
                                                 const __u8 *wmem, __u8 size);
 extern ssize_t wiimote_cmd_read(struct wiimote_data *wdata, __u32 offset,