Input: add match() method to input hanlders

Get rid of blacklist in input handler structure and instead allow
handlers to define their own match() method to perform fine-grained
filtering of supported devices.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

4 files changed, 40 insertions, 35 deletions

diff --git a/drivers/char/keyboard.c b/drivers/char/keyboard.c
index cbf64b985ef4..ada25bb8941e 100644
--- a/drivers/char/keyboard.c
+++ b/drivers/char/keyboard.c
@@ -1323,6 +1323,21 @@ static void kbd_event(struct input_handle *handle, unsigned int event_type,
         schedule_console_callback();
 }
 
+static bool kbd_match(struct input_handler *handler, struct input_dev *dev)
+{
+        int i;
+
+        if (test_bit(EV_SND, dev->evbit))
+                return true;
+
+        if (test_bit(EV_KEY, dev->evbit))
+                for (i = KEY_RESERVED; i < BTN_MISC; i++)
+                        if (test_bit(i, dev->keybit))
+                                return true;
+
+        return false;
+}
+
 /*
  * When a keyboard (or other input device) is found, the kbd_connect
  * function is called. The function then looks at the device, and if it
@@ -1334,14 +1349,6 @@ static int kbd_connect(struct input_handler *handler, struct input_dev *dev,
 {
         struct input_handle *handle;
         int error;
-        int i;
-
-        for (i = KEY_RESERVED; i < BTN_MISC; i++)
-                if (test_bit(i, dev->keybit))
-                        break;
-
-        if (i == BTN_MISC && !test_bit(EV_SND, dev->evbit))
-                return -ENODEV;
 
         handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
         if (!handle)
@@ -1407,6 +1414,7 @@ MODULE_DEVICE_TABLE(input, kbd_ids);
 
 static struct input_handler kbd_handler = {
         .event          = kbd_event,
+        .match          = kbd_match,
         .connect        = kbd_connect,
         .disconnect     = kbd_disconnect,
         .start          = kbd_start,
diff --git a/drivers/input/input.c b/drivers/input/input.c
index 7080a9d4b840..dae49eba6ccd 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -723,12 +723,13 @@ EXPORT_SYMBOL(input_set_keycode);
                 if (i != BITS_TO_LONGS(max)) \
                         continue;
 
-static const struct input_device_id *input_match_device(const struct input_device_id *id,
+static const struct input_device_id *input_match_device(struct input_handler *handler,
                                                         struct input_dev *dev)
 {
+        const struct input_device_id *id;
         int i;
 
-        for (; id->flags || id->driver_info; id++) {
+        for (id = handler->id_table; id->flags || id->driver_info; id++) {
 
                 if (id->flags & INPUT_DEVICE_ID_MATCH_BUS)
                         if (id->bustype != dev->id.bustype)
@@ -756,7 +757,8 @@ static const struct input_device_id *input_match_device(const struct input_devic
                 MATCH_BIT(ffbit,  FF_MAX);
                 MATCH_BIT(swbit,  SW_MAX);
 
-                return id;
+                if (!handler->match || handler->match(handler, dev))
+                        return id;
         }
 
         return NULL;
@@ -767,10 +769,7 @@ static int input_attach_handler(struct input_dev *dev, struct input_handler *han
         const struct input_device_id *id;
         int error;
 
-        if (handler->blacklist && input_match_device(handler->blacklist, dev))
-                return -ENODEV;
-
-        id = input_match_device(handler->id_table, dev);
+        id = input_match_device(handler, dev);
         if (!id)
                 return -ENODEV;
 
diff --git a/drivers/input/joydev.c b/drivers/input/joydev.c
index b1bd6dd32286..63e71f2a7acc 100644
--- a/drivers/input/joydev.c
+++ b/drivers/input/joydev.c
@@ -775,6 +775,20 @@ static void joydev_cleanup(struct joydev *joydev)
                 input_close_device(handle);
 }
 
+
+static bool joydev_match(struct input_handler *handler, struct input_dev *dev)
+{
+        /* Avoid touchpads and touchscreens */
+        if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_TOUCH, dev->keybit))
+                return false;
+
+        /* Avoid tablets, digitisers and similar devices */
+        if (test_bit(EV_KEY, dev->evbit) && test_bit(BTN_DIGI, dev->keybit))
+                return false;
+
+        return true;
+}
+
 static int joydev_connect(struct input_handler *handler, struct input_dev *dev,
                           const struct input_device_id *id)
 {
@@ -894,22 +908,6 @@ static void joydev_disconnect(struct input_handle *handle)
         put_device(&joydev->dev);
 }
 
-static const struct input_device_id joydev_blacklist[] = {
-        {
-                .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
-                                INPUT_DEVICE_ID_MATCH_KEYBIT,
-                .evbit = { BIT_MASK(EV_KEY) },
-                .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
-        },      /* Avoid itouchpads and touchscreens */
-        {
-                .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
-                                INPUT_DEVICE_ID_MATCH_KEYBIT,
-                .evbit = { BIT_MASK(EV_KEY) },
-                .keybit = { [BIT_WORD(BTN_DIGI)] = BIT_MASK(BTN_DIGI) },
-        },      /* Avoid tablets, digitisers and similar devices */
-        { }     /* Terminating entry */
-};
-
 static const struct input_device_id joydev_ids[] = {
         {
                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
@@ -936,13 +934,13 @@ MODULE_DEVICE_TABLE(input, joydev_ids);
 
 static struct input_handler joydev_handler = {
         .event          = joydev_event,
+        .match          = joydev_match,
         .connect        = joydev_connect,
         .disconnect     = joydev_disconnect,
         .fops           = &joydev_fops,
         .minor          = JOYDEV_MINOR_BASE,
         .name           = "joydev",
         .id_table       = joydev_ids,
-        .blacklist      = joydev_blacklist,
 };
 
 static int __init joydev_init(void)
diff --git a/include/linux/input.h b/include/linux/input.h
index 6c9d3d49fa91..8dc5d724c703 100644
--- a/include/linux/input.h
+++ b/include/linux/input.h
@@ -1200,6 +1200,8 @@ struct input_handle;
  *      it may not sleep
  * @filter: similar to @event; separates normal event handlers from
  *      "filters".
+ * @match: called after comparing device's id with handler's id_table
+ *      to perform fine-grained matching between device and handler
  * @connect: called when attaching a handler to an input device
  * @disconnect: disconnects a handler from input device
  * @start: starts handler for given handle. This function is called by
@@ -1211,8 +1213,6 @@ struct input_handle;
  * @name: name of the handler, to be shown in /proc/bus/input/handlers
  * @id_table: pointer to a table of input_device_ids this driver can
  *      handle
- * @blacklist: pointer to a table of input_device_ids this driver should
- *      ignore even if they match @id_table
  * @h_list: list of input handles associated with the handler
  * @node: for placing the driver onto input_handler_list
  *
@@ -1235,6 +1235,7 @@ struct input_handler {
 
         void (*event)(struct input_handle *handle, unsigned int type, unsigned int code, int value);
         bool (*filter)(struct input_handle *handle, unsigned int type, unsigned int code, int value);
+        bool (*match)(struct input_handler *handler, struct input_dev *dev);
         int (*connect)(struct input_handler *handler, struct input_dev *dev, const struct input_device_id *id);
         void (*disconnect)(struct input_handle *handle);
         void (*start)(struct input_handle *handle);
@@ -1244,7 +1245,6 @@ struct input_handler {
         const char *name;
 
         const struct input_device_id *id_table;
-        const struct input_device_id *blacklist;
 
         struct list_head        h_list;
         struct list_head        node;