Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c fixes from Wolfram Sang:
 "Mostly driver bugfixes, but also a few cleanups which are nice to have
  out of the way"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: rk3x: Restore clock settings at resume time
  i2c: Spelling s/acknowedge/acknowledge/
  i2c: designware: save the preset value of DW_IC_SDA_HOLD
  Documentation: i2c: slave-interface: add note for driver development
  i2c: mux: demux-pinctrl: run properly with multiple instances
  i2c: bcm-kona: fix inconsistent indenting
  i2c: rcar: use proper device with dma_mapping_error
  i2c: sh_mobile: use proper device with dma_mapping_error
  i2c: mux: demux-pinctrl: invalidate properly when switching fails

Documentation/i2c/slave-interface

@@ -145,6 +145,11 @@ If you want to add slave support to the bus driver:
 
 * Catch the slave interrupts and send appropriate i2c_slave_events to the backend.
 
+Note that most hardware supports being master _and_ slave on the same bus. So,
+if you extend a bus driver, please make sure that the driver supports that as
+well. In almost all cases, slave support does not need to disable the master
+functionality.
+
 Check the i2c-rcar driver as an example.