diff options
-rw-r--r-- | drivers/hid/i2c-hid/i2c-hid.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c index c6630d4..ce01d59 100644 --- a/drivers/hid/i2c-hid/i2c-hid.c +++ b/drivers/hid/i2c-hid/i2c-hid.c @@ -502,23 +502,31 @@ static int i2c_hid_get_raw_report(struct hid_device *hid, { struct i2c_client *client = hid->driver_data; struct i2c_hid *ihid = i2c_get_clientdata(client); + size_t ret_count, ask_count; int ret; if (report_type == HID_OUTPUT_REPORT) return -EINVAL; - if (count > ihid->bufsize) - count = ihid->bufsize; + /* +2 bytes to include the size of the reply in the query buffer */ + ask_count = min(count + 2, (size_t)ihid->bufsize); ret = i2c_hid_get_report(client, report_type == HID_FEATURE_REPORT ? 0x03 : 0x01, - report_number, ihid->inbuf, count); + report_number, ihid->inbuf, ask_count); if (ret < 0) return ret; - count = ihid->inbuf[0] | (ihid->inbuf[1] << 8); + ret_count = ihid->inbuf[0] | (ihid->inbuf[1] << 8); + if (!ret_count) + return 0; + + ret_count = min(ret_count, ask_count); + + /* The query buffer contains the size, dropping it in the reply */ + count = min(count, ret_count - 2); memcpy(buf, ihid->inbuf + 2, count); return count; |