The modalias attribute of spi devices doesn't have the "spi:" prefix
that is used in the UEVENT and in spi device drivers. This patch adds
the prefix so the modprobe can correctly match modules to devices.
Reported-by: David Daney <david.daney@cavium.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Trivial simplification. Instead of requiring spi master drivers to
always set the bus number (even when a dynamic number is desired),
this patch modifies spi_alloc_master() to initialize num_chipselect to
1 (because there will always be at least one CS) and bus_num to -1 for
dynamic allocation. This simplifies the code needed to be written for
drivers.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Currently the prepare/unprepare transfer are called unconditionally.
The assumption is that every driver using the spi core queue infrastructure
has to populate the prepare and unprepare functions. This encourages
drivers to populate empty functions to prevent crashing.
This patch prevents the call to prepare/unprepare if not populated.
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
[grant.likely: fix whitespace defect]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The SPI device tree support code isn't shared by any other subsystem. It can
be moved into the core drivers/spi directory and the exported symbol can be
removed.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
We should release the lock here and enable IRQs before returning.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[grant.likely: move unlock above dev_err() call]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Some systems have SPI devices located on plugin modules which are
enumerated at runtime as devices. The drivers for these plugin modules
need to register their SPI devices at probe() time so want to be able
to call spi_register_board_info() but that function is currently marked
as __init rather than __devinit so this usage isn't legal. Change the
annotation to __devinit to handle this.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This rips the message queue in the PL022 driver out and pushes
it into (optional) common infrastructure. Drivers that want to
use the message pumping thread will need to define the new
per-messags transfer methods and leave the deprecated transfer()
method as NULL.
Most of the design is described in the documentation changes that
are included in this patch.
Since there is a queue that need to be stopped when the system
is suspending/resuming, two new calls are implemented for the
device drivers to call in their suspend()/resume() functions:
spi_master_suspend() and spi_master_resume().
ChangeLog v1->v2:
- Remove Kconfig entry and do not make the queue support optional
at all, instead be more agressive and have it as part of the
compulsory infrastructure.
- If the .transfer() method is implemented, delete print a small
deprecation notice and do not start the transfer pump.
- Fix a bitrotted comment.
ChangeLog v2->v3:
- Fix up a problematic sequence courtesy of Chris Blair.
- Stop rather than destroy the queue on suspend() courtesy of
Chris Blair.
Signed-off-by: Chris Blair <chris.blair@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Device are added as children of the bus master's parent device, but
spi_unregister_master() looks for devices to unregister in the bus
master's children. This results in the child devices not being
unregistered.
Fix this by registering devices as direct children of the bus master.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Sort the SPI makefile and enforce the naming convention spi_*.c for
spi drivers.
This change also rolls the contents of atmel_spi.h into the .c file
since there is only one user of that particular include file.
v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be
be the predominant pattern for subsystem prefixes.
- Clean up filenames in Kconfig and header comment blocks
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Currently the simple SPI I/O operations all take pointers to u8 * buffers
to operate on. This creates needless type compatibility issues and the
underlying spi_transfer structure uses void pointers anyway so convert the
API over to take void pointers too.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Allow SPI drivers to use runtime PM and other dev_pm_ops features by
implementing dev_pm_ops for the bus. The existing bus specific suspend
and resume functions will be called if a driver does not provide dev_pm_ops
allowing for transition to the new model.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
This was fixed by David Lamparter in v2.6.36-rc5 3486008 ("spi: free
children in spi_unregister_master, not siblings") and broken again in
v2.6.37-rc1~2^2~4 during the merge of 2b9603a0 ("spi: enable
spi_board_info to be registered after spi_master").
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David Lamparter <equinox@diac24.net>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch removes convention of passing a static string as a
parameter to another static string. The convention is intended to
reduce text usage by sharing the common bits of the string, but the
implementation is inherently fragile (a change to one format string
but not the other will nullify any possible advantage), it isn't
necessarily a net win depending on what this compiler does, and it
it reduces code readability.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
[grant.likely@secretlab.ca: removed dev_dbg->dev_err hunk]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Currently spi_register_board_info() has to be called before its related
spi_master be registered, otherwise these board info will be just ignored.
This patch will remove this order limit, it adds a global spi master list
like the existing global board info listr. Whenever a board info or a
spi_master is registered, the spi master list or board info list
will be scanned, and a new spi device will be created if there is a
master-board info match.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch adds the OF hook to the spi core so that devices
can automatically be registered based on device tree data. This fixes
a problem with spi devices not binding to drivers after the cleanup of
the spi & i2c binding code.
Signed-off-by: Sinan Akman <sinan@writeme.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
introduced by 49dce689 ("spi doesn't need class_device") and bad-fixed
by 350d0076 ("spi: fix double-free on spi_unregister_master"),
spi_unregister_master would previously device_unregister all of the spi
master's siblings (instead of its children). hilarity ensues.
fix it to unregister children.
Signed-off-by: David Lamparter <equinox@diac24.net>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
* 'next-spi' of git://git.secretlab.ca/git/linux-2.6:
spi/amba_pl022: Fix probe and remove hook section annotations.
spi/mpc5121: change annotations for probe and remove functions
spi/bitbang: reinitialize transfer parameters for every message
spi/spi-gpio: add support for controllers without MISO or MOSI pin
spi/bitbang: add support for SPI_MASTER_NO_{TX, RX} modes
SPI100k: Fix 8-bit and RX-only transfers
spi/mmc_spi: mmc_spi adaptations for SPI bus locking API
spi/mmc_spi: SPI bus locking API, using mutex
Fix trivial conflict in drivers/spi/mpc512x_psc_spi.c due to 'struct
of_device' => 'struct platform_device' rename and __init/__exit to
__devinit/__devexit fix.
Move of_register_spi_devices() call from drivers to
spi_register_master(). Also change the function to use
the struct device_node pointer from master spi device
instead of passing it as function argument.
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
SPI bus locking API to allow exclusive access to the SPI bus, especially, but
not limited to, for the mmc_spi driver.
Coded according to an outline from Grant Likely; here is his
specification (accidentally swapped function names corrected):
It requires 3 things to be added to struct spi_master.
- 1 Mutex
- 1 spin lock
- 1 flag.
The mutex protects spi_sync, and provides sleeping "for free"
The spinlock protects the atomic spi_async call.
The flag is set when the lock is obtained, and checked while holding
the spinlock in spi_async(). If the flag is checked, then spi_async()
must fail immediately.
The current runtime API looks like this:
spi_async(struct spi_device*, struct spi_message*);
spi_sync(struct spi_device*, struct spi_message*);
The API needs to be extended to this:
spi_async(struct spi_device*, struct spi_message*)
spi_sync(struct spi_device*, struct spi_message*)
spi_bus_lock(struct spi_master*) /* although struct spi_device* might
be easier */
spi_bus_unlock(struct spi_master*)
spi_async_locked(struct spi_device*, struct spi_message*)
spi_sync_locked(struct spi_device*, struct spi_message*)
Drivers can only call the last two if they already hold the spi_master_lock().
spi_bus_lock() obtains the mutex, obtains the spin lock, sets the
flag, and releases the spin lock before returning. It doesn't even
need to sleep while waiting for "in-flight" spi_transactions to
complete because its purpose is to guarantee no additional
transactions are added. It does not guarantee that the bus is idle.
spi_bus_unlock() clears the flag and releases the mutex, which will
wake up any waiters.
The difference between spi_async() and spi_async_locked() is that the
locked version bypasses the check of the lock flag. Both versions
need to obtain the spinlock.
The difference between spi_sync() and spi_sync_locked() is that
spi_sync() must hold the mutex while enqueuing a new transfer.
spi_sync_locked() doesn't because the mutex is already held. Note
however that spi_sync must *not* continue to hold the mutex while
waiting for the transfer to complete, otherwise only one transfer
could be queued up at a time!
Almost no code needs to be written. The current spi_async() and
spi_sync() can probably be renamed to __spi_async() and __spi_sync()
so that spi_async(), spi_sync(), spi_async_locked() and
spi_sync_locked() can just become wrappers around the common code.
spi_sync() is protected by a mutex because it can sleep
spi_async() needs to be protected with a flag and a spinlock because
it can be called atomically and must not sleep
Signed-off-by: Ernst Schwab <eschwab@online.de>
[grant.likely@secretlab.ca: use spin_lock_irqsave()]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Matt Fleming <matt@console-pimps.org>
Tested-by: Antonio Ospite <ospite@studenti.unina.it>
The memory for dev variable is allocated as a part of
spi_device structure memory which the dev belongs to.
Thus when the memory is released the right pointer is used.
Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
In success case the function bus_find_device_by_name calls
get_device. In our context put_device should be called to
decrease the device count usage.
Signed-off-by: Roman Tereshonkov <roman.tereshonkov@nokia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Grant Likely
Shubhrajyoti D
Guennadi Liakhovetski
Dan Carpenter
Mark Brown
Uwe Kleine-König
Linus Walleij
Laurent Pinchart
Paul Gortmaker
Lucas De Marchi
Sebastian Andrzej Siewior
Linus Walleij
Feng Tang
Sinan Akman
David Lamparter
Linus Torvalds
Anatolij Gustschin
Ernst Schwab
Roman Tereshonkov