diff options
author | Qipan Li <Qipan.Li@csr.com> | 2014-03-01 05:38:17 +0100 |
---|---|---|
committer | Mark Brown <broonie@linaro.org> | 2014-03-03 04:22:20 +0100 |
commit | eeb7139524d1851c29b5c02b3dcd6679299a104e (patch) | |
tree | 330b91bd194e8024559ad597b0a1c905f53168db /arch/arm/nwfpe | |
parent | spi: sirf: Use SIMPLE_DEV_PM_OPS macro (diff) | |
download | linux-eeb7139524d1851c29b5c02b3dcd6679299a104e.tar.xz linux-eeb7139524d1851c29b5c02b3dcd6679299a104e.zip |
spi: sirf: provide a shortcut for spi command-data mode
there are many SPI clients which use the following protocal:
step 1: send command bytes to clients(rx buffer is empty)
step 2: send data bytes to clients or receive data bytes from
clients.
SiRFprimaII provides a shortcut for this kind of SPI transfer.
when tx buf is less or equal than 4 bytes and rx buf is null
in a transfer, we think it as 'command' data and use hardware
command register for the transfer.
here we can save some CPU loading than doing both tx and rx
for a normal transfer.
Signed-off-by: Qipan Li <Qipan.Li@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'arch/arm/nwfpe')
0 files changed, 0 insertions, 0 deletions