[PATCH v6 0/5] i2c: ocores: improvements

[Federico Vaga]

This patch set provides improvements to the i2c-ocore driver.

[V5 -> V6]
- remove redundant code introduced in V5 (double read control register)

[V4 -> V5]
- deterministic status of IEN bit in register "CONTROL" at the end of
  ocores_init()
- more style fixes

[V3 -> V4]
- add reviews-by/tested-by
- add comment to justify the formula in
    udelay((8 * 1000) / i2c->bus_clock_khz);

[V2 -> V3]
- fix particular error condition on platform_get_irq(). Copied from
  https://patchwork.ozlabs.org/patch/1038409/

[V1 -> V2]
- replaced usleep_range() with udelay() so that the polling version can be
  used in atomic context.
- added dedicated patch for minor style issues
- fixed delay computation
- use spin_lock_irqsave(), instead of spin_trylock_irqsave(). IACK is always
  necessary and a trylock would generate an extra interrupt for nothing
- make the driver ready for an eventual master_xfer_irqless()