Commit Graph

3 Commits

Author SHA1 Message Date
Mika Westerberg 028af5941d mfd: intel-lpss: Pass SDA hold time to I2C host controller driver
Intel Skylake the LPSS I2C pad circuit has internal delays that require
programming non-zero SDA hold time for the I2C host controller. If this is
not done communication to slave devices may fail with arbitration lost
errors like the one seen below taken from Lenovo Yoga 900:

  i2c_hid i2c-SYNA2B29:00: Fetching the HID descriptor
  i2c_hid i2c-SYNA2B29:00: __i2c_hid_command: cmd=20 00
  i2c_designware i2c_designware.1: i2c_dw_handle_tx_abort: lost arbitration

To fix this we follow what the Windows driver is doing and pass the default
SDA hold time of 230 ns to all Intel Skylake host controllers. This still
allows the platform to override these values by passing special ACPI
methods SSCN and FMCN.

Reported-by: Kevin Fenzi <kevin@scrye.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-07 02:29:24 +01:00
Mika Westerberg 6a636ec0ab mfd: lpss: Add Broxton ACPI IDs
Intel Broxton has the same LPSS block than Intel Sunrisepoint so add
Broxton ACPI IDs to the list.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-10-30 18:57:33 +00:00
Andy Shevchenko 4b45efe852 mfd: Add support for Intel Sunrisepoint LPSS devices
The new coming Intel platforms such as Skylake will contain Sunrisepoint PCH.
The main difference to the previous platforms is that the LPSS devices are
compound devices where usually main (SPI, HSUART, or I2C) and DMA IPs are
present.

This patch brings the driver for such devices found on Sunrisepoint PCH.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
2015-07-28 09:56:47 +01:00