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* i2c: Remove unneeded xxx_set_drvdata(..., NULL) callsDoug Anderson2013-02-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | There is simply no reason to be manually setting the private driver data to NULL in the remove/fail to probe cases. This is just extra cruft code that can be removed. A few notes: * Nothing relies on drvdata being set to NULL. * The __device_release_driver() function eventually calls dev_set_drvdata(dev, NULL) anyway, so there's no need to do it twice. * I verified that there were no cases where xxx_get_drvdata() was being called in these drivers and checking for / relying on the NULL return value. This could be cleaned up kernel-wide but for now just take the baby step and remove from the i2c subsystem. Reported-by: Wolfram Sang <wsa@the-dreams.de> Reported-by: Stephen Warren <swarren@wwwdotorg.org> Signed-off-by: Doug Anderson <dianders@chromium.org> Reviewed-by: Jean Delvare <khali@linux-fr.org> Acked-by: Peter Korsgaard <jacmet@sunsite.dk> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Marek Vasut <marex@denx.de> Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
* i2c: i2c-bfin-twi: Move blackfin TWI register access Macro to head file.Sonic Zhang2012-07-13
| | | | | | | Depend on 1e92bf6d80b5a0a137455c96bf6cdd9c1a5b531e Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-bfin-twi: Move TWI peripheral pin request array to platform data.Sonic Zhang2012-07-13
| | | | | | | Depend on commit cf93feb3a0dee97c7896016a352a3226139fbcf4 Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c:i2c-bfin-twi: include twi head fileSonic Zhang2012-07-13
| | | | | | | | | TWI bit mask macros are moved to twi head file. Depend on commit 61c16b5c7414b6d0511dc384e0ea994e250e6339 Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Bob Liu <lliubbo@gmail.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c:i2c-bfin-twi: TWI fails to restart next transfer in high system load.Sonic Zhang2012-07-13
| | | | | | | | | | | | | | | | | | | | | Current driver was developed based on BF537 0.2 HRM. In high system load, BUFRDERR error interrupt may be raised if XMTSERV interrupt of last TX byte is not served in time (set RSTART bit), which breaks restart tranfer as expected. "Buffer Read Error (BUFRDERR)" description in Blackfin HRM only applys to BF537 rev. < 0.3. In later rev. and later announced Blackfin chips, such as BF527 and BF548, a new TWI master feature "Clock Stretching" is added into the TWI controller, BUFRDERR interrupt is not triggered after TX FIFO is empty. This patch sets RSTART bit at the beginning of the first transfer. The SCL and SDA is hold till XMTSERV interrupt of last TX byte is served. Restart transfer is not broken in high system load. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> [wsa: fixed spaces around operators] Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-bfin-twi: Tighten condition when failing I2C transfer if MEN bit is ↵Sonic Zhang2012-07-13
| | | | | | | | | | | | | | | | | | | reset unexpectedly. In order to mark I2C transfer fail when MEN bit in I2C controller is reset unexpectedly in MCOMP interrupt, interrupt status bits XMTSERV or RCVSERV should be checked. Master Transfer Complete (MCOMP). [1] The initiated master transfer has completed. In the absence of a repeat start, the bus has been released. [0] The completion of a transfer has not been detected. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> [wsa: fixed spaces around operators and typo in commit message] Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-bfin-twi: Break dead waiting loop if i2c device misbehaves.Sonic Zhang2012-07-13
| | | | | | | | | | Some fault i2c device may hold the sda/scl line and cause i2c driver wait in the BUS busy loop. The I2C framework already retry the transfer loop before timeout. Return -EAGAIN instead of pull BUSBUSY in the other loop. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-bfin-twi: Improve the patch for bug "Illegal i2c bus lock upon ↵Sonic Zhang2012-07-13
| | | | | | | | | | | | | | | | | | certain transfer scenarios". For transfer counts > 255 bytes i2c-bfin-twi sets the data transfer counter DCNT to 0xFF indicating unlimited transfers. It then uses a flag iface->manual_stop to manually issue the STOP condition, once the required amount of bytes are received. We found that on I2C receive operation issuing the STOP condition together with a FULL RCV FIFO (2bytes) will cause SDA and SCL be constantly driven low. This patch stops receiving operation immediately in last rx interrupt. This patch also wakes up waiting process when transfer completes. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-bfin-twi: Illegal i2c bus lock upon certain transfer scenarios.Michael Hennerich2012-07-13
| | | | | | | | | | | | | | | | | | For transfer counts > 255 bytes i2c-bfin-twi sets the data transfer counter DCNT to 0xFF indicating unlimited transfers. It then uses a flag iface->manual_stop to manually issue the STOP condition, once the required amount of bytes are received. We found that on I2C receive operation issuing the STOP condition together with a FULL RCV FIFO (2bytes) will cause SDA and SCL be constantly driven low. Temporary workaround until further investigation: Discard the RCV FIFO before issuing the STOP condition. Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c-bfin-twi: Use struct dev_pm_ops for power managementRafael J. Wysocki2012-07-12
| | | | | | | | | | Make the Blackfin On-Chip Two Wire Interface driver define its PM callbacks through a struct dev_pm_ops object rather than by using legacy PM hooks in struct platform_driver. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: irq: Remove IRQF_DISABLEDYong Zhang2011-10-29
| | | | | | | | | | | | | | | | Since commit [c58543c8: genirq: Run irq handlers with interrupts disabled], We run all interrupt handlers with interrupts disabled and we even check and yell when an interrupt handler returns with interrupts enabled (see commit [b738a50a: genirq: Warn when handler enables interrupts]). So now this flag is a NOOP and can be removed. Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Barry Song <21cnbao@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: abort transfer is MEM bit is reset unexpectedlySonic Zhang2011-06-27
| | | | | | | | | | | | | | | Sometimes, the first I2C transmit interrupt is not serviced in time (like when higher priority interrupts take too long). Since the RESTART bit is not set before the next I2C clock, when the TWI handler is finally called, the I2C session is aborted (MEM bit is reset) and both SMITSERV and MCOMP int status bits are set. So when this happens, abort the transfer. Reported-by: Isabelle Leonardi <i.leonardi@detracom.fr> Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: move setup to the earlier subsys initcallMichael Hennerich2011-01-12
| | | | | | | | | | | Some systems using this bus sometimes have very basic devices such as regulators on the bus, so the I2C bus master needs to be loaded early. This also matches the behavior of many other I2C bus master drivers. Therefore initialize via subsys_initcall(). Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: handle faulty slave devices betterMichael Hennerich2011-01-12
| | | | | | | | | | Faulty slave devices might drive SDA low after a transfer finishes. So, when this scenario is detected, have the master generate up to 9 extra clocks until the SDA is properly released. Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: return completion in interrupt for smbus quick transfersSonic Zhang2010-05-19
| | | | | | | | A smbus quick transfer has no data after the address byte. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: remove redundant retrySonic Zhang2010-05-19
| | | | | | Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: fix lost interrupts at high speedsSonic Zhang2010-05-19
| | | | | | | | | | i2c event of next read/write byte may trigger before current int state is cleared in the interrupt handler. So, this should be done at the beginning of interrupt handler to avoid losing new i2c events. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: add debug output for error statusMichael Hennerich2010-05-19
| | | | | | | | Add some debug() code to decode the error register. Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: integrate timeout timer with completion interfaceSonic Zhang2010-05-19
| | | | | | | | | | There isn't much point in managing our own custom timeout timer when the completion interface already includes support for it. This makes the resulting code much simpler and robust. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h 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>
* i2c-bfin-twi: fix CLKDIV calculationSonic Zhang2009-12-23
| | | | | | | | | | Calculation of the CLKDIV speed setting should be done using base 10 math rather than base 2. We also avoid exceeding the spec due to integer truncation and a 50% duty cycle. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c: Use resource_size macroLinus Walleij2009-06-16
| | | | | | | | | | | | | | | | | This replace all instances in the i2c busses tree of res->end - res->start + 1 with the handy macro resource_size(res) from ioport.h (coming in from platform_device.h). This was created with a simple sed -i -e 's/\([a-z]*\)->end *- *[a-z]*->start *+ *1/resource_size(\1)/g' Then manually replacing the PXA redefiniton of the same kind of macro manually. Recompiled some ARM defconfigs I could find to make a rough test so it shouldn't break anything, though I couldn't see exactly which configs you need for all the drivers. Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-bfin-twi: pull in io.h for ioremap()Mike Frysinger2009-06-16
| | | | | | | | Rather than relying on some of the headers implicitly pulling in io.h, pull it in explicitly our self for ioremap() and friends. Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c: Blackfin TWI: implement I2C_FUNC_SMBUS_I2C_BLOCK functionalityMichael Hennerich2009-06-13
| | | | | | | | | | Some drivers need i2c_smbus_read_i2c_block_data() functionality, so add support for it to the Blackfin I2C bus driver. Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> [ben-linux@fluff.org: shortened subject] Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c: Blackfin TWI: fix transfer errors with repeat startFrank Shew2009-06-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | We have a custom BF537 board with an I2C RTC (MAX DS3231) running uclinux 2007R1 for some time. Recently during migration to 2008R1.5-RC3 we losted access to the RTC. The RTC driver calls 'i2c_transfer()' which in turns calls 'bfin_twi_master_xfer()' in i2c-bfin-twi.c. Compared with 2007R1, it looks like the 2008R1.5 version of i2c-bin-twi.c has a new mode 'TWI_I2C-MODE_REPEAT' which corresponds to the Repeat Start Condition described in the HRM. However, according to the HRM, at XMIT or RECV interrupt and when the data count is 0, not only is the RESTART bit supposed to be set, but MDIR must also be set if the next operation is a receive sequence, and cleared if not. Currently there is no code that looks at the I2C_M_RD bit in the flag from the next cur_msg and set/clear the MDIR flag accordingly at the same time that the RSTART bit is set. Instead, MDIR is set or cleared (by OR'ing with 0?) after the RESTART bit has been cleared during handling of MCOMP interrupt. It appears that this is causing our failure with reading the RTC, as a quick patch to set/clear MDIR when RESTART is set seem to solve our problem. Signed-off-by: Frank Shew <fshew@geometrics.com> Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> [ben-linux@fluff.org: shorted subject] Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c: Blackfin TWI: fix REPEAT START mode doesn't repeatSonic Zhang2009-06-13
| | | | | | | | | | | | | | Avoid rewrite TWI MASTER_CTL reg when issue next message In i2c repeat transfer mode, byte count of next message should be filled into part of the TWI MASTER_CTL reg when interrupt MCOMP of last message transfer is triggered. But, other bits in this reg should not be touched. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> [ben-linux@fluff.org: shorted subject] Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c: Blackfin TWI: make sure we don't end up with a CLKDIV=0Michael Hennerich2009-06-13
| | | | | | | | | | | Make sure we don't end up with an invalid CLKDIV=0 in case someone specifies 20kHz SCL or less (5 * 1024 / 20 = 0x100). Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Bryan Wu <cooloney@kernel.org> [ben-linux@fluff.org: shortened subject line] Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c: Delete many unused adapter IDsJean Delvare2009-01-26
| | | | Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Drop I2C_CLASS_ALLJean Delvare2009-01-07
| | | | | | | | | | | I2C_CLASS_ALL is almost never what bus driver authors really want. These i2c classes are really only about which devices must be probed, not what devices can be present. As device drivers get converted to the new i2c device driver model, only a few device types will keep relying on probing. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Sonic Zhang <sonic.zhang@analog.com>
* i2c: Blackfin I2C Driver: Functional power management supportMichael Hennerich2008-07-28
| | | | | | | | | | PM_SUSPEND_MEM: Blackfin does not maintain register state through Hibernate. Save and restore peripheral base initialization during PM transitions. Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c: Fix platform driver hotplug/coldplugKay Sievers2008-04-22
| | | | | | | | | | | | Since 43cc71eed1250755986da4c0f9898f9a635cb3bf, the platform modalias is prefixed with "platform:". Add MODULE_ALIAS() to the hotpluggable I2C platform drivers, to allow module auto loading. [ db: add some more drivers ] Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-bfin-twi: Fix mismatch in add timer and delete timerHans Schillstrom2008-04-22
| | | | | | | | | | Move init_completion to just before i2c transfer. http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=3385 Signed-off-by: Hans Schillstrom <hans.schillstrom@shlsys.com> Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-bfin-twi: Use simpler comment headers and strip out information that is ↵Mike Frysinger2008-04-22
| | | | | | | | maintained in the scm's log Signed-off-by: Mike Frysinger <vapier.adi@gmail.com> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-bfin-twi: Cleanup driver descriptions, versions and some module useful ↵Bryan Wu2008-04-22
| | | | | | | information Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-bfin-twi: Add missing pin mux operationBryan Wu2008-04-22
| | | | | | | | | | Blackfin TWI controller hardware pin should be requested from GPIO port controller Before BF54x, there is no need to do this. But as long as BF54x and BF52x are supported by this generic driver, the missing pin mux operation should be added. Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-bfin-twi: Add platform_resource interface to support multi-port TWI ↵Bryan Wu2008-04-22
| | | | | | | | | | | controllers - Dynamic alloc the resource of TWI driver data according to board information - TWI register read/write accessor based on dynamic regs_base - Support TWI0/TWI1 for BF54x Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-bfin-twi: Add repeat start feature to avoid break of a bundle of i2c ↵Sonic Zhang2008-04-22
| | | | | | | | | | | master xfer operation - Create a new mode TWI_I2C_MODE_REPEAT. - No change to smbus operation. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-bfin-twi: Register adapter with a specific bus numberKalle Pokki2008-01-27
| | | | | | | | | All the users of this driver explicitly specify the I2C bus numbers to be used in their platform data. Make the driver respect that. Signed-off-by: Kalle Pokki <kalle.pokki@eke.fi> Cc: Bryan Wu <bryan.wu@analog.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-bfin-twi: Remove useless twi_lock mutexFrancis Moreau2007-10-13
| | | | | | | | | | Remove this unneeded mutex. Indeed it was used to serialize access to the hardware, but this is already done by the i2c-core layer, see 'bus_lock' mutex used by i2c_transfer(). Signed-off-by: Francis Moreau <francis.moro@gmail.com> Acked-by: Bryan Wu <bryan.wu@analog.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Blackfin Two Wire Interface driverBryan Wu2007-05-01
The i2c linux driver for blackfin architecture which supports blackfin on-chip TWI controller i2c operation. Signed-off-by: Bryan Wu <bryan.wu@analog.com> Reviewed-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>