lwn.git/drivers/spi/spi.c, branch v2.6.37

drivers/spi/spi.c: don't release the spi device twice

2010-12-23T03:43:34+00:00

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 Signed-off-by: David Lamparter Cc: Grant Likely Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

spi: fixed odd static string conventions in core code

2010-10-22T15:51:05+00:00

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 [grant.likely@secretlab.ca: removed dev_dbg->dev_err hunk] Signed-off-by: Grant Likely

spi: enable spi_board_info to be registered after spi_master

2010-10-22T05:52:16+00:00

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 Signed-off-by: Grant Likely

of/spi: Fix OF-style driver binding of spi devices

2010-10-03T03:28:29+00:00

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 Signed-off-by: Grant Likely

spi: free children in spi_unregister_master, not siblings

2010-09-01T15:15:24+00:00

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 Signed-off-by: Grant Likely

Merge branch 'next-spi' of git://git.secretlab.ca/git/linux-2.6

2010-08-14T18:54:09+00:00

* '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.

of/spi: call of_register_spi_devices() from spi core code

2010-07-30T06:03:59+00:00

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 Signed-off-by: Grant Likely

spi/mmc_spi: SPI bus locking API, using mutex

2010-06-29T00:49:29+00:00

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 [grant.likely@secretlab.ca: use spin_lock_irqsave()] Signed-off-by: Grant Likely Tested-by: Matt Fleming Tested-by: Antonio Ospite

spi: spi_device memory should be released instead of device.

2010-04-28T07:17:58+00:00

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 Signed-off-by: Grant Likely

spi: release device claimed by bus_find_device_by_name

2010-04-28T07:14:05+00:00

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 Signed-off-by: Grant Likely