The cw1200_spi driver tries to mirror the cw1200_sdio driver's lock
API, which relies on sdio_claim_host/sdio_release_host to serialize
hardware operations across multiple threads.
Unfortunately the implementation was flawed, as it lacked a way to wake
up the lock requestor when there was contention, often resulting in a
hang.
This problem was uncovered while trying to fix the
spi-transfers-in-interrupt-context BUG() corrected in the previous
patch. Many thanks to Dave Sizeburns for his assistance in fixing this.
Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When we get an interrupt from the hardware, the first thing the driver does
is tell the device to mask off the interrupt line. Unfortunately this
involves a SPI transaction in interrupt context. Some (most?) SPI
controllers perform the transfer asynchronously and try to sleep.
This is bad, and triggers a BUG().
So, work around this by using adding a hwbus hook for the cw1200 driver
core to call. The cw1200_spi driver translates this into
irq_disable()/irq_enable() calls instead, which can safely be called in
interrupt context.
Apparently the platforms I used to develop the cw1200_spi driver used
synchronous spi_sync() implementations, which is why this didn't surface
until now.
Many thanks to Dave Sizeburns for the inital bug report and his services
as a tester.
Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Most of these relate to endianness problems, and are purely cosmetic.
But a couple of them were legit -- listen interval parsing and some of
the rate selection code would malfunction on BE systems.
There's still one cosmetic warning remaining, in the (admittedly) ugly
code in cw1200_spi.c. It's there because the hardware needs 16-bit SPI
transfers, but many SPI controllers only operate 8 bits at a time.
If there's a cleaner way of handling this, I'm all ears.
Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
My previous patch just moved the file, but it also needed to be renamed
to conform to proper conventions.
Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The only advantage of 'struct resource' is that it lets us assign names
as part of the platform data. Unfortunately since we are using platform
data, we are already limited to a single instance of each driver,
rendering this moot.
So, replace the struct resources with ints, resulting in cleaner code.
This was based on a suggestion from Arnd Bergmann.
Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This avoids problems when building on SPARC targets due to the driver
calling the bus abstraction layer 'sbus'. Not that any SBUS-sporting
SPARC targets are likely to have an SDIO controller, but this is the
correct thing to do.
See http://kisskb.ellerman.id.au/kisskb/buildresult/8846508/
Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Remove including <linux/version.h> that don't need it.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
module_spi_driver() makes the code simpler by eliminating
boilerplate code.
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Intel's 0-day kernel build tester caught this build failure. This patch
properly wraps everything that depends on CONFIG_PM.
Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
