Commit Graph

5 Commits

Author SHA1 Message Date
Gao Pan d2ad0a62d4 spi: fsl-lpspi: use wait_for_completion_timeout() while waiting transfer done
It's a potential problem to use wait_for_completion() because the
completion condition may never come. Thus, it's better to repalce
wait_for_completion() with wait_for_completion_timeout().

Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-30 17:45:51 +00:00
Gao Pan 14de3918ea spi: imx: replace schedule() with cond_resched()
It's more rational that just do the schedule when necessary
other than do it every time. Thus, it's better to replace
schedule() with cond_resched() in fsl_lpspi_txfifo_empty(),
which contributes to saving cpu time.

Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-25 13:04:47 +00:00
Gao Pan e3a49390eb spi: imx: fix potential shift truncation
There is a static checker warning in fsl_lpspi_set_cmd().
I intended to write "temp |= (fsl_lpspi->config.mode & 0x3) << 30",
but used "temp |= (fsl_lpspi->config.mode & 0x11) << 30" by mistake.

This patch fixes this potential shift truncation.

Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-25 13:04:42 +00:00
Gao Pan 3ffa1a5dc6 spi: imx: use prepare_transfer_hardware() for lpspi
The old driver enable clk in fsl_lpspi_prepare_message() and
disable clk in fsl_lpspi_unprepare_message().

Rather than doing this per message it's a bit better to do it
in prepare_transfer_hardware(), that way if there's a sequence
of messages queued one after another we don't turn the clock on
and off all the time.

Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-25 13:04:41 +00:00
Gao Pan 5314987de5 spi: imx: add lpspi bus driver
This patch adds lpspi driver to support new i.MX products which use
lpspi instead of ecspi.

The lpspi can continue operating in stop mode when an appropriate
clock is available. It is also designed for low CPU overhead with
DMA offloading of FIFO register accesses.

Signed-off-by: Gao Pan <pandy.gao@nxp.com>
Reviewed-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-11-22 19:13:16 +00:00