]> git.baikalelectronics.ru Git - kernel.git/commit
Input: iqs5xx - accommodate bootloader latency
authorJeff LaBundy <jeff@labundy.com>
Mon, 25 Jan 2021 04:17:08 +0000 (20:17 -0800)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Mon, 25 Jan 2021 04:49:04 +0000 (20:49 -0800)
commit1302c71a30615226838f3583028d122f6792d720
tree6edfccf682b0c9261a88b8c7ce0b6d74fc3a9713
parent2539da6677b6355e124b99d1dbe15eb1066f1d46
Input: iqs5xx - accommodate bootloader latency

The bootloader NAK's all I2C communication after the first 64-byte
bulk write if the bus frequency is equal to 400 kHz. This prevents
the platform from pushing updated firmware to the device.

The vendor's USB bootloader programming dongle appears to insert a
delay between the "open" command and the first 64-byte bulk write.
Adding a similar delay to the driver seems to eliminate the issue.

Furthermore, the dongle does not access the bootloader immediately
after powering up the device. Follow suit by adding a delay before
the "open" command to avoid wasted retries at 400 kHz.

Signed-off-by: Jeff LaBundy <jeff@labundy.com>
Link: https://lore.kernel.org/r/1611002626-5889-4-git-send-email-jeff@labundy.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
drivers/input/touchscreen/iqs5xx.c