commit 052dc7c45i "spi/dw_spi: conditional transfer mode change"
introduced cs_control code, which has a bug by using bit offset
for spi mode to set transfer mode in control register. Also it
forces devices who don't need cs_control to re-configure the
control registers for each spi transfer. This patch will fix them
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Allow interrupt sharing since exclusive interrupt line for
DW SPI controller is not provided on every platform.
Signed-off-by: Yong Wang <yong.y.wang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
So that interface drivers could be built as modules
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This allows the switching between transfer modes between 'transmit only',
'receive only' and 'transmit and receive' modes. Due to the design of the SPI
block, changing transfer modes requires that the block be disabled; in doing
so the chipselect line is inherently deasserted and (usually) the attached
device discards its state. Consequentially, switching modes requires that a
platform-specific chipselect function has been defined so that the chipselect
is not dropped during the change.
Signed-off-by: George Shore <george@georgeshore.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The 'poll_transfer' function employs a conditional to test whether the
transmit buffer is valid; in doing so, on a receive operation no data is
clocked out, thus no data is clocked in and ultimately errors appear.
This removes the conditional as the transmit function will be set to a null
writer when the transmit buffer is invalid, allowing the driver to clock
0x00 out to the device to receive data from the device.
Signed-off-by: George Shore <george@georgeshore.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
FIFO depth is configurable for each implementation of DW core,
so add a depth detection for those interface drivers who don't set
the fifo_len explicitly
Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Jean-Hugues Deschenes <jean-hugues.deschenes@octasic.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Now dw_spi core fully supports 3 transfer modes: pure polling,
DMA and IRQ mode. IRQ mode will use the FIFO half empty as
the IRQ trigger, so each interface driver need set the fifo_len,
so that core driver can handle it properly
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Make the driver wait at least for 1 jiffie before issuing the
warning, no matter what HZ is set to
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Driver for the Designware SPI core, it supports multipul interfaces like
PCI/APB etc. User can use "dw_apb_ssi_db.pdf" from Synopsys as HW
datasheet.
[randy.dunlap@oracle.com: fix build]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Feng Tang <feng.tang@intel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
