1. Nov 01, 2013
  2. Oct 31, 2013
  3. Oct 30, 2013
  4. Oct 06, 2013
    • Marek Vasut's avatar
      i2c: mxs: Fix PIO mode on i.MX23 · 19e221be
      Marek Vasut authored
      
      
      The i.MX23 I2C controller is also capable of PIO, but needs a little harder
      push to behave. The controller needs to be reset after every PIO/DMA operation
      for some reason, otherwise in rare cases, the controller can hang or emit
      bytes onto the bus.
      
      Signed-off-by: default avatarMarek Vasut <marex@denx.de>
      Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
      19e221be
    • Marek Vasut's avatar
      i2c: mxs: Rework the PIO mode operation · 29faeb38
      Marek Vasut authored
      
      
      Analyze and rework the PIO mode operation. The PIO mode operation
      was unreliable on MX28, by analyzing the bus with LA, the checks
      for when data were available or were to be sent were wrong.
      
      The PIO WRITE has to be completely reworked as it multiple problems.
      The MX23 datasheet helped here, see comments in the code for details.
      The problems boil down to:
      - RUN bit in CTRL0 must be set after DATA register was written
      - The PIO transfer must be 4 bytes long tops, otherwise use
        clock stretching.
      Both of these fixes are implemented.
      
      The PIO READ operation can only be done for up to four bytes as
      we are unable to read out the data from the DATA register fast
      enough.
      
      This patch also tries to document the investigation within the
      code.
      
      Signed-off-by: default avatarMarek Vasut <marex@denx.de>
      Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
      29faeb38
    • Juergen Beisert's avatar
      i2c: mxs: distinguish i.MX23 and i.MX28 based I2C controller · 616228a1
      Juergen Beisert authored
      
      
      It seems the PIO mode does not work, or at least not like it works
      on a i.MX28. Each short transfer needs about one second (without an
      error message) but does not send anything on the I2C lines.
      
      Signed-off-by: default avatarJuergen Beisert <jbe@pengutronix.de>
      Signed-off-by: default avatarMarek Vasut <marex@denx.de>
      Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
      616228a1
  5. Oct 04, 2013
  6. Sep 30, 2013
  7. Sep 29, 2013