On Wed, Dec 5, 2012 at 11:10 AM, Jean Delvare [off-list ref] wrote:

On Tue,  4 Dec 2012 16:27:51 +0100, Benjamin Tissoires wrote:

quoted

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 <redacted>
---
 drivers/hid/i2c-hid/i2c-hid.c | 68 ++++++++++++++++++-------------------------
 1 file changed, 28 insertions(+), 40 deletions(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index dcacfc4..4e3f80b 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c

@@ -465,48 +465,38 @@ 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,

@@ -611,22 +601,19 @@ 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))

@@ -844,8 +831,9 @@ 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)

Yes, looks much better.

Reviewed-by: Jean Delvare <redacted>

Thanks Jean,

as mentioned in 2/14, this patch need the fix in 2/14 to be able to
work. Jiri, I'll try to send a v2 ASAP so that you can pick both in
the right order (otherwise, the bisect may fall between the two).

Cheers,
Benjamin

--
Jean Delvare