Input: synaptics-rmi4 - only read the F54 query registers which are used

The F54 driver is currently only using the first 6 bytes of F54 so there is
no need to read all 27 bytes. Some Dell systems (Dell XP13 9333 and
similar) have an issue with the touchpad or I2C bus when reading reports
larger then 16 bytes. Reads larger then 16 bytes are reported in two HID
reports. Something about the back to back reports seems to cause the next
read to report incorrect data. This results in F30 failing to load and the
click button failing to work.

Previous issues with the I2C controller or touchpad were addressed in:
commit 5b65c2a029 ("HID: rmi: check sanity of the incoming report")

Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=195949
Signed-off-by: Andrew Duggan <aduggan@synaptics.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Reviewed-by: Nick Dyer <nick@shmanahar.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Andrew Duggan 2017-06-23 00:04:51 -07:00 committed by Dmitry Torokhov
parent 817ae460c7
commit 9768935264
1 changed files with 7 additions and 10 deletions

View File

@ -31,9 +31,6 @@
#define F54_GET_REPORT 1
#define F54_FORCE_CAL 2
/* Fixed sizes of reports */
#define F54_QUERY_LEN 27
/* F54 capabilities */
#define F54_CAP_BASELINE (1 << 2)
#define F54_CAP_IMAGE8 (1 << 3)
@ -95,7 +92,6 @@ struct rmi_f54_reports {
struct f54_data {
struct rmi_function *fn;
u8 qry[F54_QUERY_LEN];
u8 num_rx_electrodes;
u8 num_tx_electrodes;
u8 capabilities;
@ -632,22 +628,23 @@ static int rmi_f54_detect(struct rmi_function *fn)
{
int error;
struct f54_data *f54;
u8 buf[6];
f54 = dev_get_drvdata(&fn->dev);
error = rmi_read_block(fn->rmi_dev, fn->fd.query_base_addr,
&f54->qry, sizeof(f54->qry));
buf, sizeof(buf));
if (error) {
dev_err(&fn->dev, "%s: Failed to query F54 properties\n",
__func__);
return error;
}
f54->num_rx_electrodes = f54->qry[0];
f54->num_tx_electrodes = f54->qry[1];
f54->capabilities = f54->qry[2];
f54->clock_rate = f54->qry[3] | (f54->qry[4] << 8);
f54->family = f54->qry[5];
f54->num_rx_electrodes = buf[0];
f54->num_tx_electrodes = buf[1];
f54->capabilities = buf[2];
f54->clock_rate = buf[3] | (buf[4] << 8);
f54->family = buf[5];
rmi_dbg(RMI_DEBUG_FN, &fn->dev, "F54 num_rx_electrodes: %d\n",
f54->num_rx_electrodes);