1. 03 Sep, 2015 5 commits
  2. 30 Aug, 2015 1 commit
  3. 28 Aug, 2015 2 commits
  4. 26 Aug, 2015 4 commits
  5. 20 Aug, 2015 1 commit
  6. 14 Aug, 2015 4 commits
  7. 12 Aug, 2015 1 commit
  8. 08 Aug, 2015 1 commit
  9. 06 Aug, 2015 3 commits
    • Simon Glass's avatar
      dm: video: Add support for the Parade PS8622/625 bridge · bcd5dfff
      Simon Glass authored
      This chip provides an eDP to LVDS bridge which is useful for SoCs that don't
      support LVDS displays (or it would waste scarce pins). The setup is included
      in the device tree.
      Signed-off-by: default avatarSimon Glass <sjg@chromium.org>
      bcd5dfff
    • Simon Glass's avatar
      i2c: Add a mux for GPIO-based I2C bus arbitration · b725dc45
      Simon Glass authored
      While I2C supports multi-master buses this is difficult to get right.
      The implementation on the master side in software is quite complex.
      Clock-stretching and the arbitrary time that an I2C transaction can take
      make it difficult to share the bus fairly in the face of high traffic.
      When one or more masters can be reset independently part-way through a
      transaction it is hard to know the state of the bus.
      
      This driver provides a scheme based on two 'claim' GPIOs, one driven by the
      AP (Application Processor, meaning the main CPU) and one driven by the EC
      (Embedded Controller, a small CPU aimed at handling system tasks). With
      these they can communicate and reliably share the bus. This scheme has
      minimal overhead and involves very little code. It is used on snow to
      permit the EC and the AP to share access to the main system PMIC and
      battery. The scheme can survive reboots by either side without difficulty.
      This scheme has been tested in the field with millions of devices.
      
      Since U-Boot runs on the AP, the terminology used is 'our' claim GPIO,
      meaning the AP's, and 'their' claim GPIO, meaning the EC's. This terminology
      is used by the device tree bindings in Linux also.
      Signed-off-by: default avatarSimon Glass <sjg@chromium.org>
      b725dc45
    • Simon Glass's avatar
      dm: i2c: Add support for multiplexed I2C buses · 3d1957f0
      Simon Glass authored
      Add a new I2C_MUX uclass. Devices in this class can multiplex between
      several I2C buses, selecting them one at a time for use by the system.
      The multiplexing mechanism is left to the driver to decide - it may be
      controlled by GPIOs, for example.
      
      The uclass supports only two methods: select() and deselect().
      
      The current mux state is expected to be stored in the mux itself since
      it is the only thing that knows how to make things work. The mux can
      record the current state and then avoid switching unless it is necessary.
      So select() can be skipped if the mux is already in the correct state.
      Also deselect() can be made a nop if required.
      Signed-off-by: default avatarSimon Glass <sjg@chromium.org>
      3d1957f0
  10. 05 Aug, 2015 6 commits
  11. 28 Jul, 2015 2 commits
  12. 23 Jul, 2015 2 commits
  13. 22 Jul, 2015 3 commits
  14. 21 Jul, 2015 3 commits
  15. 15 Jul, 2015 2 commits