linux/drivers/i2c
Zhuo-hao Lee 664d58bf4d i2c: designware: save the preset value of DW_IC_SDA_HOLD
There are several ways to set the SDA hold time for i2c controller,
including: Device Tree, built-in device properties and ACPI. However,
if the SDA hold time is not specified by above method, we should
read the value, where it is preset by firmware, and save it to
sda_hold_time. This is needed because when i2c controller enters
runtime suspend, the DW_IC_SDA_HOLD value will be reset to chipset
default value. And during runtime resume, i2c_dw_init will be called
to reconfigure i2c controller. If sda_hold_time is zero, the chipset
default hold time will be used, that will be too short for some
platforms. Therefore, to have a better tolerance, the DW_IC_SDA_HOLD
value should be kept by sda_hold_time.

Signed-off-by: Zhuo-hao Lee <zhuo-hao.lee@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-09-08 22:14:36 +02:00
..
algos i2c: algo-bit: declare i2c_bit_quirk_no_clk_stretch as static 2016-05-11 17:16:30 +02:00
busses i2c: designware: save the preset value of DW_IC_SDA_HOLD 2016-09-08 22:14:36 +02:00
muxes i2c: mux: demux-pinctrl: run properly with multiple instances 2016-09-08 16:56:21 +02:00
i2c-boardinfo.c i2c: remove __init from i2c_register_board_info() 2016-06-19 14:13:50 +02:00
i2c-core.c Merge branch 'i2c/for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2016-07-27 14:19:25 -07:00
i2c-core.h i2c: remove FSF address 2014-11-07 18:35:33 +01:00
i2c-dev.c i2c-dev: don't get i2c adapter via i2c_dev 2016-07-08 10:29:31 +09:00
i2c-mux.c i2c: mux: relax locking of the top i2c adapter during mux-locked muxing 2016-05-04 22:39:17 +02:00
i2c-slave-eeprom.c i2c: Drop owner assignment from i2c_driver 2015-08-10 08:37:35 +02:00
i2c-smbus.c i2c: i2c-smbus: fix i2c_handle_smbus_host_notify documentation 2016-07-18 20:09:54 +02:00
i2c-stub.c i2c: i2c-stub: sort includes 2016-02-20 23:33:39 +01:00
Kconfig i2c: Update the description of I2C_SMBUS 2016-07-18 20:11:08 +02:00
Makefile i2c: slave-eeprom: add eeprom simulator driver 2014-12-11 22:25:54 +01:00