[PATCH v2] i2c-hid: fix length for set/get report in i2c hid

From: Huzefa Kankroliwala
Date: Wed Apr 03 2013 - 16:42:29 EST


With the current i2c hid driver set/get report does not work
as expected, for e.g sensor hub properties like power state,
frequency etc is not set properly on the device as a result
we do not get events.
The problem is that i2c hid driver in function i2c_hid_request
sets length equal to default buffer size for which the sensor
hub does not respond on get/set commands. Use report length
and calculate it based on report size and id.

Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
Signed-off-by: Huzefa Kankroliwala <huzefa.nomanx.kankroliwala@xxxxxxxxx>
---
drivers/hid/i2c-hid/i2c-hid.c | 9 ++++-----
1 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 935f387..2b1799a 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -567,18 +567,17 @@ static void i2c_hid_request(struct hid_device *hid, struct hid_report *rep,
int reqtype)
{
struct i2c_client *client = hid->driver_data;
- struct i2c_hid *ihid = i2c_get_clientdata(client);
char *buf;
int ret;
+ int len = i2c_hid_get_report_length(rep) - 2;

- buf = kzalloc(ihid->bufsize, GFP_KERNEL);
+ buf = kzalloc(len, GFP_KERNEL);
if (!buf)
return;

switch (reqtype) {
case HID_REQ_GET_REPORT:
- ret = i2c_hid_get_raw_report(hid, rep->id, buf, ihid->bufsize,
- rep->type);
+ ret = i2c_hid_get_raw_report(hid, rep->id, buf, len, rep->type);
if (ret < 0)
dev_err(&client->dev, "%s: unable to get report: %d\n",
__func__, ret);
@@ -587,7 +586,7 @@ static void i2c_hid_request(struct hid_device *hid, struct hid_report *rep,
break;
case HID_REQ_SET_REPORT:
hid_output_report(rep, buf);
- i2c_hid_output_raw_report(hid, buf, ihid->bufsize, rep->type);
+ i2c_hid_output_raw_report(hid, buf, len, rep->type);
break;
}

--
1.7.4.1

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