| Message ID | 20170423045842.8892-1-jake@merdich.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/drivers/input/rmi4/rmi_driver.c b/drivers/input/rmi4/rmi_driver.c index d64fc92858f2..8724ee241ee5 100644 --- a/drivers/input/rmi4/rmi_driver.c +++ b/drivers/input/rmi4/rmi_driver.c @@ -545,6 +545,9 @@ static int rmi_scan_pdt_page(struct rmi_device *rmi_dev, retval = callback(rmi_dev, ctx, &pdt_entry); if (retval != RMI_SCAN_CONTINUE) return retval; + + // Dell 9Q33 garbles data if scanned too quickly + usleep_range(500, 1000); } /*
Dell 9Q33's touchpad has been getting invalid function addresses during the late stages of probing. This only occurs after the PDT was scanned multiple times, so it only popped up now that PDT scanning was unified in 0b2c7a89 (previously, hid-rmi.c scanned it only once). This slows down probing enough to always get good data, at the cost of ~1ms of sleep per function probe (value determined empirically), or about 20ms total when enumerating. If someone has a better idea of handling this (maybe caching the PDT's?), I'd be happy to test. Signed-off-by: Jake Merdich <jake@merdich.com> --- drivers/input/rmi4/rmi_driver.c | 3 +++ 1 file changed, 3 insertions(+)