HID: i2c-hid: reorder allocation/free of buffers

Simplifies i2c_hid_alloc_buffers tests, and makes this function
responsible of the assignment of ihid->bufsize.
The condition for the reallocation in i2c_hid_start is then simpler.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 34cca428a6a99799fe0ac566efd89b5fbb2c8537..d00f1854cb8266bdc39358e46e88a6fe914c9d95 100644 (file)
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -464,48 +464,38 @@ static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
        }
 }
 
-static int i2c_hid_alloc_buffers(struct i2c_hid *ihid)
+static void i2c_hid_free_buffers(struct i2c_hid *ihid)
+{
+       kfree(ihid->inbuf);
+       kfree(ihid->argsbuf);
+       kfree(ihid->cmdbuf);
+       ihid->inbuf = NULL;
+       ihid->cmdbuf = NULL;
+       ihid->argsbuf = NULL;
+       ihid->bufsize = 0;
+}
+
+static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
 {
        /* the worst case is computed from the set_report command with a
         * reportID > 15 and the maximum report length */
        int args_len = sizeof(__u8) + /* optional ReportID byte */
                       sizeof(__u16) + /* data register */
                       sizeof(__u16) + /* size of the report */
-                      ihid->bufsize; /* report */
-
-       ihid->inbuf = kzalloc(ihid->bufsize, GFP_KERNEL);
-
-       if (!ihid->inbuf)
-               return -ENOMEM;
+                      report_size; /* report */
 
+       ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
        ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
-
-       if (!ihid->argsbuf) {
-               kfree(ihid->inbuf);
-               return -ENOMEM;
-       }
-
        ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
 
-       if (!ihid->cmdbuf) {
-               kfree(ihid->inbuf);
-               kfree(ihid->argsbuf);
-               ihid->inbuf = NULL;
-               ihid->argsbuf = NULL;
+       if (!ihid->inbuf || !ihid->argsbuf || !ihid->cmdbuf) {
+               i2c_hid_free_buffers(ihid);
                return -ENOMEM;
        }
 
-       return 0;
-}
+       ihid->bufsize = report_size;
 
-static void i2c_hid_free_buffers(struct i2c_hid *ihid)
-{
-       kfree(ihid->inbuf);
-       kfree(ihid->argsbuf);
-       kfree(ihid->cmdbuf);
-       ihid->inbuf = NULL;
-       ihid->cmdbuf = NULL;
-       ihid->argsbuf = NULL;
+       return 0;
 }
 
 static int i2c_hid_get_raw_report(struct hid_device *hid,
@@ -610,22 +600,19 @@ static int i2c_hid_start(struct hid_device *hid)
        struct i2c_client *client = hid->driver_data;
        struct i2c_hid *ihid = i2c_get_clientdata(client);
        int ret;
-       int old_bufsize = ihid->bufsize;
+       unsigned int bufsize = HID_MIN_BUFFER_SIZE;
 
-       ihid->bufsize = HID_MIN_BUFFER_SIZE;
-       i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &ihid->bufsize);
-       i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &ihid->bufsize);
-       i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &ihid->bufsize);
+       i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
+       i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
+       i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
 
-       if (ihid->bufsize > old_bufsize || !ihid->inbuf || !ihid->cmdbuf) {
+       if (bufsize > ihid->bufsize) {
                i2c_hid_free_buffers(ihid);
 
-               ret = i2c_hid_alloc_buffers(ihid);
+               ret = i2c_hid_alloc_buffers(ihid, bufsize);
 
-               if (ret) {
-                       ihid->bufsize = old_bufsize;
+               if (ret)
                        return ret;
-               }
        }
 
        if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
@@ -849,8 +836,9 @@ static int __devinit i2c_hid_probe(struct i2c_client *client,
        /* we need to allocate the command buffer without knowing the maximum
         * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
         * real computation later. */
-       ihid->bufsize = HID_MIN_BUFFER_SIZE;
-       i2c_hid_alloc_buffers(ihid);
+       ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
+       if (ret < 0)
+               goto err;
 
        ret = i2c_hid_fetch_hid_descriptor(ihid);
        if (ret < 0)