spi: remove completely broken Tegra driver
authorStephen Warren <swarren@nvidia.com>
Fri, 28 Sep 2012 16:15:48 +0000 (10:15 -0600)
committerMark Brown <broonie@opensource.wolfsonmicro.com>
Mon, 1 Oct 2012 12:29:49 +0000 (13:29 +0100)
commit536a53a300d0d40152796eefb0a9e6e36ca37f7d
treee644203945ee780d8a1a4cdc656d9b4984f5361d
parentf4b81dd83e38277a3d1e6661f0fa8eea8cfe784b
spi: remove completely broken Tegra driver

The current SPI driver has many issues. Examples are:

* Segfaulting on most transfers due to expecting all transfers to have
  both RX and TX buffers.
* Hanging on TX transfers since the whole driver flow is driven by RX
  DMA completion, but the HW is only told to enable RX for RX transfers.
* Use of clk_disable_unprepare() from atomic context.
* Once those and other minor issues are fixed, the driver still doesn't
  actually work.
* The driver also implements a deprecated API to the SPI core.

For this reason, simply remove the driver completely. This has two
advantages:

1) This will remove the last use of Tegra's <mach/dma.h>, which will
   allow that file to be removed, which is required for single zImage
   work.

2) The downstream driver is significaly different from the current
   code. I believe a patch to re-add the downstream driver (with
   appropriate cleanup) will be much simpler to review if it's a new
   file rather than randomly interspered with essentially unrelated
   existing code.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
drivers/spi/Kconfig
drivers/spi/Makefile
drivers/spi/spi-tegra.c [deleted file]