Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

[pandora-kernel.git] / drivers / input / input.c

diff --git a/drivers/input/input.c b/drivers/input/input.c
index c6f88eb..cc763c9 100644 (file)
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -782,10 +782,29 @@ static unsigned int input_proc_devices_poll(struct file *file, poll_table *wait)
        return 0;
 }
 
+union input_seq_state {
+       struct {
+               unsigned short pos;
+               bool mutex_acquired;
+       };
+       void *p;
+};
+
 static void *input_devices_seq_start(struct seq_file *seq, loff_t *pos)
 {
-       if (mutex_lock_interruptible(&input_mutex))
-               return NULL;
+       union input_seq_state *state = (union input_seq_state *)&seq->private;
+       int error;
+
+       /* We need to fit into seq->private pointer */
+       BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
+
+       error = mutex_lock_interruptible(&input_mutex);
+       if (error) {
+               state->mutex_acquired = false;
+               return ERR_PTR(error);
+       }
+
+       state->mutex_acquired = true;
 
        return seq_list_start(&input_dev_list, *pos);
 }
@@ -795,9 +814,12 @@ static void *input_devices_seq_next(struct seq_file *seq, void *v, loff_t *pos)
        return seq_list_next(v, &input_dev_list, pos);
 }
 
-static void input_devices_seq_stop(struct seq_file *seq, void *v)
+static void input_seq_stop(struct seq_file *seq, void *v)
 {
-       mutex_unlock(&input_mutex);
+       union input_seq_state *state = (union input_seq_state *)&seq->private;
+
+       if (state->mutex_acquired)
+               mutex_unlock(&input_mutex);
 }
 
 static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
@@ -861,7 +883,7 @@ static int input_devices_seq_show(struct seq_file *seq, void *v)
 static const struct seq_operations input_devices_seq_ops = {
        .start  = input_devices_seq_start,
        .next   = input_devices_seq_next,
-       .stop   = input_devices_seq_stop,
+       .stop   = input_seq_stop,
        .show   = input_devices_seq_show,
 };
 
@@ -881,40 +903,49 @@ static const struct file_operations input_devices_fileops = {
 
 static void *input_handlers_seq_start(struct seq_file *seq, loff_t *pos)
 {
-       if (mutex_lock_interruptible(&input_mutex))
-               return NULL;
+       union input_seq_state *state = (union input_seq_state *)&seq->private;
+       int error;
+
+       /* We need to fit into seq->private pointer */
+       BUILD_BUG_ON(sizeof(union input_seq_state) != sizeof(seq->private));
+
+       error = mutex_lock_interruptible(&input_mutex);
+       if (error) {
+               state->mutex_acquired = false;
+               return ERR_PTR(error);
+       }
+
+       state->mutex_acquired = true;
+       state->pos = *pos;
 
-       seq->private = (void *)(unsigned long)*pos;
        return seq_list_start(&input_handler_list, *pos);
 }
 
 static void *input_handlers_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
-       seq->private = (void *)(unsigned long)(*pos + 1);
-       return seq_list_next(v, &input_handler_list, pos);
-}
+       union input_seq_state *state = (union input_seq_state *)&seq->private;
 
-static void input_handlers_seq_stop(struct seq_file *seq, void *v)
-{
-       mutex_unlock(&input_mutex);
+       state->pos = *pos + 1;
+       return seq_list_next(v, &input_handler_list, pos);
 }
 
 static int input_handlers_seq_show(struct seq_file *seq, void *v)
 {
        struct input_handler *handler = container_of(v, struct input_handler, node);
+       union input_seq_state *state = (union input_seq_state *)&seq->private;
 
-       seq_printf(seq, "N: Number=%ld Name=%s",
-                  (unsigned long)seq->private, handler->name);
+       seq_printf(seq, "N: Number=%u Name=%s", state->pos, handler->name);
        if (handler->fops)
                seq_printf(seq, " Minor=%d", handler->minor);
        seq_putc(seq, '\n');
 
        return 0;
 }
+
 static const struct seq_operations input_handlers_seq_ops = {
        .start  = input_handlers_seq_start,
        .next   = input_handlers_seq_next,
-       .stop   = input_handlers_seq_stop,
+       .stop   = input_seq_stop,
        .show   = input_handlers_seq_show,
 };