1. 19 9月, 2009 3 次提交
    • J
      i2c/tsl2550: Use combined SMBus transactions · ac780941
      Jean Delvare 提交于
      Make the I/O faster, mainly by using combined SMBus transactions when
      possible. While the TSL2550 datasheet doesn't say the device supports
      them, they seem to work just fine in practice, and a combined
      transaction is faster than two simple transactions in many cases and
      always more reliable.
      
      A side effect is to suppress the delays between SMBus writes and
      reads. The datasheet doesn't say they are needed and things work just
      fine for me without them.
      
      I also couldn't see any reason for the delay between reading the two
      channels. Nor for the loop to get a reading in the first place. The
      400 ms delay between samples only matters at chip power-up, after that
      the chip always hold the previously sampled value so we never get to
      wait.
      
      All these changes make reading the lux value much faster and cheaper.
      Signed-off-by: NJean Delvare <khali@linux-fr.org>
      Tested-by: NMichele De Candia <michele.decandia@valueteam.com>
      Cc: Rodolfo Giometti <giometti@linux.it>
      ac780941
    • J
      i2c-taos-evm: Switch echo off to improve performance · 27693ce5
      Jean Delvare 提交于
      When echo is on, we waste time reading back our orders. Switching echo
      off makes performance much better: SMBus byte data transactions are 47%
      faster and byte transactions are 24% faster.
      Signed-off-by: NJean Delvare <khali@linux-fr.org>
      27693ce5
    • J
      i2c: Drop unused i2c_driver.id field · 6a891a31
      Jean Delvare 提交于
      Nobody is using i2c_driver.id any longer, so we can drop that field.
      Signed-off-by: NJean Delvare <khali@linux-fr.org>
      6a891a31
  2. 18 9月, 2009 37 次提交