Hans de Goede 1a48aaabf1 i2c: acpi: Force bus speed to 400KHz if a Silead touchscreen is present ... commit 7574c0db2e upstream. Many cheap devices use Silead touchscreen controllers. Testing has shown repeatedly that these touchscreen controllers work fine at 400KHz, but for unknown reasons do not work properly at 100KHz. This has been seen on both ARM and x86 devices using totally different i2c controllers. On some devices the ACPI tables list another device at the same I2C-bus as only being capable of 100KHz, testing has shown that these other devices work fine at 400KHz (as can be expected of any recent I2C hw). This commit makes i2c_acpi_find_bus_speed() always return 400KHz if a Silead touchscreen controller is present, fixing the touchscreen not working on devices which ACPI tables' wrongly list another device on the same bus as only being capable of 100KHz. Specifically this fixes the touchscreen on the Jumper EZpad 6 m4 not working. Reported-by: youling 257 <youling257@gmail.com> Tested-by: youling 257 <youling257@gmail.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> [wsa: rewording warning a little] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2019-11-20 18:45:17 +01:00
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algos	i2c: algos: bit: make the error messages grepable	2018-08-30 23:11:42 +02:00
busses	i2c: stm32f7: remove warning when compiling with W=1	2019-11-10 11:27:33 +01:00
muxes	Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into i2c/for-4.19	2018-08-04 23:05:11 +02:00
i2c-boardinfo.c	i2c: i2c-boardinfo: fix memory leaks on devinfo	2017-11-27 19:14:29 +01:00
i2c-core-acpi.c	i2c: acpi: Force bus speed to 400KHz if a Silead touchscreen is present	2019-11-20 18:45:17 +01:00
i2c-core-base.c	gcc-9: don't warn about uninitialized variable	2019-08-09 17:52:27 +02:00
i2c-core-of.c	i2c: of: Try to find an I2C adapter matching the parent	2019-04-05 22:33:11 +02:00
i2c-core-slave.c	i2c: remove i2c_lock_adapter and use i2c_lock_bus directly	2018-07-13 00:09:37 +02:00
i2c-core-smbus.c	i2c: smbus: add unlocked __i2c_smbus_xfer variant	2018-07-20 23:51:37 +02:00
i2c-core.h	i2c: make i2c_check_addr_validity() static	2018-03-24 14:07:23 +01:00
i2c-dev.c	i2c: dev: fix potential memory leak in i2cdev_ioctl_rdwr	2019-06-22 08:15:17 +02:00
i2c-mux.c	Merge branch 'i2c/for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux	2018-08-21 17:40:46 -07:00
i2c-slave-eeprom.c
i2c-smbus.c	i2c: i2c-smbus: add of_i2c_setup_smbus_alert	2017-10-28 23:42:47 +02:00
i2c-stub.c	treewide: kzalloc() -> kcalloc()	2018-06-12 16:19:22 -07:00
Kconfig	Merge branch 'i2c/for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux	2016-12-15 12:56:35 -08:00
Makefile	i2c: don't use any __deprecated handling anymore	2018-08-24 17:26:43 +02:00