[PATCH v3 0/2] Qualcomm Universal Peripheral (QUP) I2C controller

Bjorn Andersson bjorn.andersson at sonymobile.com
Thu Feb 20 19:38:08 EST 2014

This third revision of the QUP I2C driver series comes with quite a bit of
cleanup and corrections. Most notably is the removal of the "magic" delay loops
and bug fixes related to larger than 32 byte reads and writes.

Special thanks to Andy Gross for helping answering questions regarding the
inner working of this block.


Changes from v3:
 - Simplified interrupt handler
 - Corrected the state transition poll timeout
 - Refactored state transition code
 - Refactored the polling functions waiting for transfers to finish
 - Made the write fifo fill function care if there's space
 - Corrected programmed length on writes
 - Made block read and block write work
 - Removed data duplicates from qup_i2c_dev
 - Changed timeout to HZ, to give room for clock stretching
 - Properly reject reads over 256 bytes, as limited by HW
 - Dropped reinitialization of completions
 - Made sure to not re-initiate reads for every block read
 - Added QUP version number to compatible

Changes from v2:
 - Removed unused variables and includes
 - Corrected read logic in irq handler
 - Made the polling loop in qup_i2c_poll_state() less arbitrary
 - Only building suspend/resume if CONFIG_PM_SLEEP

Changes from v1:
 - Cleaned up device tree binding example.
 - Refrased device tree bindings.
 - Following changes in the i2c framework.
 - Use the core clock to calculate divider for the bus clock, instead of
   explicitly setting it.
 - Remove explicit pinctrl settting.
 - Split/renamed qup_i2c_enable(bool) into enable/disable functions.
 - Return value was overwritten on error in write_one/read_one.
 - Initialize the i2c core every time, so that we actually can execute
   more than 1 transmission per xfer.

Bjorn Andersson (1):
  i2c: New bus driver for the Qualcomm QUP I2C controller

Ivan T. Ivanov (1):
  i2c: qup: Add device tree bindings information

 .../devicetree/bindings/i2c/qcom,i2c-qup.txt       |   44 ++
 drivers/i2c/busses/Kconfig                         |   10 +
 drivers/i2c/busses/Makefile                        |    1 +
 drivers/i2c/busses/i2c-qup.c                       |  772 ++++++++++++++++++++
 4 files changed, 827 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i2c/qcom,i2c-qup.txt
 create mode 100644 drivers/i2c/busses/i2c-qup.c


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