1 files changed, 71 insertions, 15 deletions

diff --git a/drivers/input/input.c b/drivers/input/input.c
index a31394c1eca8..6c161e220868 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -24,6 +24,7 @@
 #include <linux/mutex.h>
 #include <linux/rcupdate.h>
 #include <linux/smp_lock.h>
+#include "input-compat.h"
 
 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
 MODULE_DESCRIPTION("Input core");
@@ -767,6 +768,40 @@ static int input_attach_handler(struct input_dev *dev, struct input_handler *han
         return error;
 }
 
+#ifdef CONFIG_COMPAT
+
+static int input_bits_to_string(char *buf, int buf_size,
+                                unsigned long bits, bool skip_empty)
+{
+        int len = 0;
+
+        if (INPUT_COMPAT_TEST) {
+                u32 dword = bits >> 32;
+                if (dword || !skip_empty)
+                        len += snprintf(buf, buf_size, "%x ", dword);
+
+                dword = bits & 0xffffffffUL;
+                if (dword || !skip_empty || len)
+                        len += snprintf(buf + len, max(buf_size - len, 0),
+                                        "%x", dword);
+        } else {
+                if (bits || !skip_empty)
+                        len += snprintf(buf, buf_size, "%lx", bits);
+        }
+
+        return len;
+}
+
+#else /* !CONFIG_COMPAT */
+
+static int input_bits_to_string(char *buf, int buf_size,
+                                unsigned long bits, bool skip_empty)
+{
+        return bits || !skip_empty ?
+                snprintf(buf, buf_size, "%lx", bits) : 0;
+}
+
+#endif
 
 #ifdef CONFIG_PROC_FS
 
@@ -835,14 +870,25 @@ static void input_seq_print_bitmap(struct seq_file *seq, const char *name,
                                    unsigned long *bitmap, int max)
 {
         int i;
-
-        for (i = BITS_TO_LONGS(max) - 1; i > 0; i--)
-                if (bitmap[i])
-                        break;
+        bool skip_empty = true;
+        char buf[18];
 
         seq_printf(seq, "B: %s=", name);
-        for (; i >= 0; i--)
-                seq_printf(seq, "%lx%s", bitmap[i], i > 0 ? " " : "");
+
+        for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
+                if (input_bits_to_string(buf, sizeof(buf),
+                                         bitmap[i], skip_empty)) {
+                        skip_empty = false;
+                        seq_printf(seq, "%s%s", buf, i > 0 ? " " : "");
+                }
+        }
+
+        /*
+         * If no output was produced print a single 0.
+         */
+        if (skip_empty)
+                seq_puts(seq, "0");
+
         seq_putc(seq, '\n');
 }
 
@@ -1131,14 +1177,23 @@ static int input_print_bitmap(char *buf, int buf_size, unsigned long *bitmap,
 {
         int i;
         int len = 0;
+        bool skip_empty = true;
+
+        for (i = BITS_TO_LONGS(max) - 1; i >= 0; i--) {
+                len += input_bits_to_string(buf + len, max(buf_size - len, 0),
+                                            bitmap[i], skip_empty);
+                if (len) {
+                        skip_empty = false;
+                        if (i > 0)
+                                len += snprintf(buf + len, max(buf_size - len, 0), " ");
+                }
+        }
 
-        for (i = BITS_TO_LONGS(max) - 1; i > 0; i--)
-                if (bitmap[i])
-                        break;
-
-        for (; i >= 0; i--)
-                len += snprintf(buf + len, max(buf_size - len, 0),
-                                "%lx%s", bitmap[i], i > 0 ? " " : "");
+        /*
+         * If no output was produced print a single 0.
+         */
+        if (len == 0)
+                len = snprintf(buf, buf_size, "%d", 0);
 
         if (add_cr)
                 len += snprintf(buf + len, max(buf_size - len, 0), "\n");
@@ -1153,7 +1208,8 @@ static ssize_t input_dev_show_cap_##bm(struct device *dev,		\
 {                                                                       \
         struct input_dev *input_dev = to_input_dev(dev);                \
         int len = input_print_bitmap(buf, PAGE_SIZE,                    \
-                                     input_dev->bm##bit, ev##_MAX, 1);  \
+                                     input_dev->bm##bit, ev##_MAX,      \
+                                     true);                             \
         return min_t(int, len, PAGE_SIZE);                              \
 }                                                                       \
 static DEVICE_ATTR(bm, S_IRUGO, input_dev_show_cap_##bm, NULL)
@@ -1217,7 +1273,7 @@ static int input_add_uevent_bm_var(struct kobj_uevent_env *env,
 
         len = input_print_bitmap(&env->buf[env->buflen - 1],
                                  sizeof(env->buf) - env->buflen,
-                                 bitmap, max, 0);
+                                 bitmap, max, false);
         if (len >= (sizeof(env->buf) - env->buflen))
                 return -ENOMEM;