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* i2c: Remove all i2c_set_clientdata(client, NULL) in driversWolfram Sang2010-06-031-1/+0
| | | | | | | | | | | | | | | | | | | | | I2C drivers can use the clientdata-pointer to point to private data. As I2C devices are not really unregistered, but merely detached from their driver, it used to be the drivers obligation to clear this pointer during remove() or a failed probe(). As a couple of drivers forgot to do this, it was agreed that it was cleaner if the i2c-core does this clearance when appropriate, as there is no guarantee for the lifetime of the clientdata-pointer after remove() anyhow. This feature was added to the core with commit e4a7b9b04de15f6b63da5ccdd373ffa3057a3681 to fix the faulty drivers. As there is no need anymore to clear the clientdata-pointer, remove all current occurrences in the drivers to simplify the code and prevent confusion. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Richard Purdie <rpurdie@linux.intel.com> Acked-by: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c/busses: Move two drivers to embedded sectionWolfram Sang2010-06-032-23/+23
| | | | | | | And fix a typo while we are here Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Rename i2c_check_addr to i2c_check_addr_busyJean Delvare2010-06-031-19/+19
| | | | | | | | Otherwise it's not clear what it is checking. Also move the function to save a forward declaration. Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Document reserved I2C addressesJean Delvare2010-06-031-3/+25
| | | | | | | | Move strict I2C address validity check to a single function, and document the reserved I2C addresses there. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Hans Verkuil <hverkuil@xs4all.nl>
* i2c: Check for address validity on client registrationJean Delvare2010-06-031-7/+26
| | | | | | | | | | | | | | | Do basic address validity checks when a client is being registered. We already had checks in place for devices which are being detected, but not for devices which are simply instantiated. This is a very basic check. We don't want to do strict checking here because some devices are known to infringe the I2C address constraints (e.g. IR receivers at 7-bit address 0x7a while this value is supposedly reserved for 10-bit addresses.) So we assume the caller knows what it is doing. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Matthieu Castet <castet.matthieu@free.fr>
* i2c: Share the I2C device presence detection codeJean Delvare2010-06-031-40/+40
| | | | | | | | | Use the same I2C device presence detection code for legacy and new device detection functions. This is more consistent and makes the code smaller. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Matthieu Castet <castet.matthieu@free.fr>
* Merge remote branch 'origin' into secretlab/next-devicetreeGrant Likely2010-05-2250-431/+656
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merging in current state of Linus' tree to deal with merge conflicts and build failures in vio.c after merge. Conflicts: drivers/i2c/busses/i2c-cpm.c drivers/i2c/busses/i2c-mpc.c drivers/net/gianfar.c Also fixed up one line in arch/powerpc/kernel/vio.c to use the correct node pointer. Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
| * i2c-nforce2: Remove redundant error messages on ACPI conflictChase Douglas2010-05-211-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | The ACPI subsystem strictly checks for resource conflicts. When there's a conflict, it outputs a warning message with all the details needed to properly diagnose the underlying issue. However, the i2c-nforce2 driver also prints its own message. Not only is the message redundant, it is at the KERN_ERR level, which overrides some bootsplash screens for no good reason. This change removes the two lines that print out the error messages. Signed-off-by: Chase Douglas <chase.douglas@canonical.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c: Use <linux/io.h> instead of <asm/io.h>H Hartley Sweeten2010-05-2132-37/+32
| | | | | | | | | | | | | | | | As warned by checkpatch.pl, <linux/io.h> should be used instead of <asm/io.h>. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c-algo-pca: Fix coding style issuesFarid Hammane2010-05-211-18/+18
| | | | | | | | | | | | | | | | | | | | | | Fix up some coding style issues. i2c-algo-pca.c has been built successfully after applying this patch and the binary object is still exactly the same. Other issues found by checkpatch.pl were voluntarily not fixed, either to keep readability, or because of false positive errors. Signed-off-by: Farid Hammane <farid.hammane@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c-dev: Fix all coding style issuesFarid Hammane2010-05-211-15/+15
| | | | | | | | | | | | | | Fix all coding style issues found by checkpatch.pl. Signed-off-by: Farid Hammane <farid.hammane@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c-core: Fix some coding style issuesFarid Hammane2010-05-211-45/+45
| | | | | | | | | | | | | | Fix up coding style issues found by the checkpatch.pl tool. Signed-off-by: Farid Hammane <farid.hammane@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c-gpio: Move initialization code to subsys_initcall()Marek Szyprowski2010-05-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GPIO driven I2C bus can be used for controlling the PMIC chip. The example of such configuration is Samsung Aquila board. This patch moves initialization code to subsys_initcall() to ensure that the i2c bus is available early so the regulators can be quickly probed and available for other devices on their probe() call. Such solution has been proposed by Mark Brown to fix the problem of the regulators not beeing available on the peripheral device probe(): http://lists.infradead.org/pipermail/linux-arm-kernel/2010-March/011971.html Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c-parport: Make template structure constJean Delvare2010-05-211-1/+1
| | | | | | | | | | | | parport_algo_data is a template so it can be marked const. Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c-dev: Remove unnecessary castsH Hartley Sweeten2010-05-211-3/+3
| | | | | | | | | | | | | | | | The private_data member of struct file is a void *, there is no need to cast it. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c-stub: Expose the default functionality flagsJean Delvare2010-05-211-4/+5
| | | | | | | | | | | | | | It is easier to adjust the flags when you know their default value. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Mark M. Hoffman <mhoffman@lightlink.com>
| * i2c/scx200_acb: Make PCI device ids constantJean Delvare2010-05-211-1/+1
| | | | | | | | | | | | | | | | Make PCI device ids constant as we just did for many other i2c bus drivers already. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Márton Németh <nm127@freemail.hu>
| * i2c-i801: Fix all checkpatch warningsIvo Manca2010-05-211-10/+10
| | | | | | | | | | | | | | Fix all checkpatch warnings. No functional changes are made. Signed-off-by: Ivo Manca <pinkel@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| * i2c-i801: All newer devices have all the optional featuresJean Delvare2010-05-211-12/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Only the oldest devices lack some of the features supported by this driver. List them explicitly, and default to all features enabled for all other chips, including the ones added through sysfs. This will make future driver maintenance easier. In the unlikely event of a not yet supported device not implementing all the features, one can always use the disable_features module parameter to prevent the driver from attempting to use them. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Seth Heasley <seth.heasley@intel.com>
| * i2c-i801: Let the user disable selected driver featuresJean Delvare2010-05-211-1/+20
| | | | | | | | | | | | | | | | | | | | Let the user disable selected features normally supported by the device. This makes it possible to work around possible driver or hardware bugs if the feature in question doesn't work as intended for whatever reason. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Felix Rubinstein <felixru@gmail.com>
| * Merge branch 'for-linus/i2c-2635' of git://git.fluff.org/bjdooks/linuxLinus Torvalds2010-05-209-174/+337
| |\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus/i2c-2635' of git://git.fluff.org/bjdooks/linux: (21 commits) i2c-highlander: remover superflous variable i2c-ibm-iic: drop NO_IRQ i2c-cpm: drop NO_IRQ i2c-mpc: drop NO_IRQ MAINTAINERS: add i2c tree for embedded platforms i2c-pxa: only define 'blue_murder'-function if DEBUG is #defined i2c-pxa: remove unused macro i2c-nomadik: fix operator precedence warning i2c-nomadik: release region when removed OMAP3: I2C: Clean up Errata 1p153 handling OMAP2/3: I2C: Errata ID i207: Clear wrong RDR interrupt omap: i2c: add a timeout to the busy waiting omap: i2c: make errata 1.153 workaround a separate function i2c-omap: add mpu wake up latency constraint in i2c omap: i2c: Add i2c support on omap4 platform i2c-bfin-twi: return completion in interrupt for smbus quick transfers i2c-bfin-twi: remove redundant retry i2c-bfin-twi: fix lost interrupts at high speeds i2c-bfin-twi: add debug output for error status i2c-bfin-twi: integrate timeout timer with completion interface ...
| | * i2c-highlander: remover superflous variableWolfram Sang2010-05-201-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When cppcheck found this flaw [./i2c/busses/i2c-highlander.c:284]: (style) Warning - using char variable in bit operation it was noted that the 'read'-variable could be simply removed as read_write can only be 0 or 1 anyhow. So, we remove the flaw and simplify the code. Reported-by: d binderman <dcb314@hotmail.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Jean Delvare <khali@linux-fr.org> Cc: Ben Dooks <ben-linux@fluff.org>
| | * i2c-ibm-iic: drop NO_IRQWolfram Sang2010-05-201-7/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Drop NO_IRQ as 0 is the preferred way to describe 'no irq' (http://lkml.org/lkml/2005/11/21/221). This change is safe, as the driver is only used on powerpc, where NO_IRQ is 0 anyhow. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Sean MacLennan <smaclennan@pikatech.com> Cc: Ben Dooks <ben-linux@fluff.org>
| | * i2c-cpm: drop NO_IRQWolfram Sang2010-05-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Drop NO_IRQ as 0 is the preferred way to describe 'no irq' (http://lkml.org/lkml/2005/11/21/221). This change is safe, as the driver is only used on powerpc, where NO_IRQ is 0 anyhow. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Jochen Friedrich <jochen@scram.de> Cc: Ben Dooks <ben-linux@fluff.org>
| | * i2c-mpc: drop NO_IRQWolfram Sang2010-05-201-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Drop NO_IRQ as 0 is the preferred way to describe 'no irq' (http://lkml.org/lkml/2005/11/21/221). This change is safe, as the driver is only used on powerpc, where NO_IRQ is 0 anyhow. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Cc: Ben Dooks <ben-linux@fluff.org>
| | * i2c-pxa: only define 'blue_murder'-function if DEBUG is #definedWolfram Sang2010-05-201-10/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This talkative function is also called on timeouts. As timeouts can happen on regular writes to EEPROMs (no error case), this creates false positives. Giving lots of details is interesting only for developers anyhow, so just use the function if DEBUG is #defined. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Eric Miao <eric.y.miao@gmail.com> Cc: Roel Kluin <roel.kluin@gmail.com> Cc: Pavel Machek <pavel@ucw.cz>
| | * i2c-pxa: remove unused macroUwe Kleine-König2010-05-201-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit beea494 ([ARM] Remove EEPROM slave emulation from i2c-pxa driver.) removed all uses of eedbg, so the definition can go, too. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Eric Miao <eric.y.miao@gmail.com> Cc: Roel Kluin <roel.kluin@gmail.com> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
| | * i2c-nomadik: fix operator precedence warningRabin Vincent2010-05-201-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix this warning: i2c-nomadik.c:707: warning: suggest parentheses around operand of '!' or change '&' to '&&' or '!' to '~' Acked-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * i2c-nomadik: release region when removedRabin Vincent2010-05-201-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | So that the module can be loaded again after an unload. Acked-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * OMAP3: I2C: Clean up Errata 1p153 handlingmanjugk manjugk2010-05-201-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clean up existing Errata 1p153 handling to use generic errata handling mechanism through dev flag. Signed-off-by: Manjunatha GK <manjugk@ti.com> Cc: Nishanth Menon <nm@ti.com> Cc: Alexander Shishkin <virtuoso@slind.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * OMAP2/3: I2C: Errata ID i207: Clear wrong RDR interruptmanjugk manjugk2010-05-201-0/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Under certain rare conditions, I2C_STAT[13].RDR bit may be set and the corresponding interrupt fire, even there is no data in the receive FIFO, or the I2C data transfer is still ongoing. These spurious RDR events must be ignored by the software. This patch handles and ignores RDR spurious interrupts. The below sequence is required in interrupt handler for handling this errata: 1. If RDR is set to 1, clear RDR 2. Read I2C status register and check for BusBusy bit. If BusBusy bit is set, skip remaining steps. 3. If BusBusy bit is not set, perform read operation on I2C status register. 4. If RDR is set, clear the same. Check RDR again and clear if it sets RDR bit again. 5. Perform I2C Data Read operation N number of times(where N is value read from the register BUFSTAT-RXSTAT bit fields). Note: This errata is not applicable for omap2420 and omap4. It is applicable for: 1. omap2430 2. omap34xx(including omap3630). Signed-off-by: Manjunatha GK <manjugk@ti.com> Cc: Hema Kalliguddi <hemahk@ti.com> Cc: Nishanth Menon <nm@ti.com> Cc: Aaro Koskinen <Aaro.Koskinen@nokia.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * omap: i2c: add a timeout to the busy waitingAlexander Shishkin2010-05-201-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The errata 1.153 workaround is busy waiting on XUDF bit in interrupt context, which may lead to kernel hangs. The problem can be reproduced by running the bus with wrong (too high) speed. Signed-off-by: Alexander Shishkin <virtuoso@slind.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * omap: i2c: make errata 1.153 workaround a separate functionAlexander Shishkin2010-05-201-19/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | This is to avoid insanely long lines and levels of indentation. Signed-off-by: Alexander Shishkin <virtuoso@slind.org> Cc: Nishant Menon <nm@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * i2c-omap: add mpu wake up latency constraint in i2cKalle Jokiniemi2010-05-201-4/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While waiting for completion of the i2c transfer, the MPU could hit OFF mode and cause several msecs of delay that made i2c transfers fail more often. The extra delays and subsequent re-trys cause i2c clocks to be active more often. This has also an negative effect on power consumption. Created a mechanism for passing and using the constraint setting function in driver code. The used mpu wake up latency constraints are now set individually per bus, and they are calculated based on clock rate and fifo size. Thanks to Jarkko Nikula, Moiz Sonasath, Paul Walmsley, and Nishanth Menon for tuning out the details of this patch. Updates by Kevin as requested by Tony: - Remove omap_set_i2c_constraint_func() in favor of conditionally adding the flag in omap_i2c_add_bus() in order to keep all the OMAP conditional checking in a single location. - Update set_mpu_wkup_lat prototypes to match OMAP PM layer so OMAP PM function can be used directly in pdata. Cc: Moiz Sonasath <m-sonasath@ti.com> Cc: Jarkko Nikula <jhnikula@gmail.com> Cc: Paul Walmsley <paul@pwsan.com> Cc: Nishanth Menon <nm@ti.com> Signed-off-by: Kalle Jokiniemi <kalle.jokiniemi@digia.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * omap: i2c: Add i2c support on omap4 platformSantosh Shilimkar2010-05-201-32/+114
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch is rebased version of earlier post to add I2C driver support to OMAP4 platform. On OMAP4, all I2C register address offsets are changed from OMAP1/2/3 I2C. In order to not have #ifdef's at various places in code, as well as to support multi-OMAP build, an array is created to hold the register addresses with it's offset. This patch was submitted, reviewed and acked on mailing list already. For more details refer below link http://www.mail-archive.com/linux-i2c@vger.kernel.org/msg02281.html This updated verion has a depedancy on "Add support for 16-bit registers" posted on linux-omap. Below is the patch-works link for the same http://patchwork.kernel.org/patch/72295/ Signed-off-by: Syed Rafiuddin <rafiuddin.syed@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Kevin Hilman <khilman@deeprootsystems.com> Reviewed-by: Paul Walmsley <paul@pwsan.com> Cc: Cory Maccarrone <darkstar6262@gmail.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * i2c-bfin-twi: return completion in interrupt for smbus quick transfersSonic Zhang2010-05-201-11/+7
| | | | | | | | | | | | | | | | | | | | | | | | 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 Zhang2010-05-201-18/+2
| | | | | | | | | | | | | | | | | | 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 Zhang2010-05-201-24/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 Hennerich2010-05-201-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | 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 Zhang2010-05-201-59/+66
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| | * i2c-s3c2410: Remove unconditional 1ms delay on each transferMark Brown2010-05-201-2/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The S3C I2C controller indicates completion of I2C transfers before the bus has a stop condition on it. In order to ensure that we do not attempt to start a new transfer before the bus is idle the driver currently inserts a 1ms delay. This is vastly larger than is generally required and has a visible effect on performance under load, such as when bringing up audio CODECs or reading back status information with non-bulk I2C reads. Replace the sleep with a spin on the IIC status register for up to 1ms. This will busy wait but testing on my SMDK6410 system indicates that the overwhelming majority of transactions complete on the first spin, with maximum latencies of less than 10 spins so the absolute overhead of busy waiting should be at worst comprable to msleep(), and the overall system performance is dramatically improved. The main risk is poor interaction with multimaster systems where we may miss the bus going idle before the next transaction. Defend against this by falling back to the original 1ms delay after 20 spins. The overall effect in my testing is an approximately 20% improvement in kernel startup time. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| * | Merge branch 'for-linus' of ↵Linus Torvalds2010-05-201-69/+97
| |\ \ | | |/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6: PM: PM QOS update fix Freezer / cgroup freezer: Update stale locking comments PM / platform_bus: Allow runtime PM by default i2c: Fix bus-level power management callbacks PM QOS update PM / Hibernate: Fix block_io.c printk warning PM / Hibernate: Group swap ops PM / Hibernate: Move the first_sector out of swsusp_write PM / Hibernate: Separate block_io PM / Hibernate: Snapshot cleanup FS / libfs: Implement simple_write_to_buffer PM / Hibernate: document open(/dev/snapshot) side effects PM / Runtime: Add sysfs debug files PM: Improve device power management document PM: Update device power management document PM: Allow runtime_suspend methods to call pm_schedule_suspend() PM: pm_wakeup - switch to using bool
| | * i2c: Fix bus-level power management callbacksRafael J. Wysocki2010-05-101-69/+97
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are three issues with the i2c bus type's power management callbacks at the moment. First, they don't include any hibernate callbacks, although they should at least include the .restore() callback (there's no guarantee that the driver will be present in memory before loading the image kernel and we must restore the pre-hibernation state of the device). Second, the "legacy" callbacks are not going to be invoked by the PM core since the bus type's pm object is not NULL. Finally, the system sleep PM (ie. suspend/resume) callbacks don't check if the device has been already suspended at run time, in which case they should skip suspending it. Also, it looks like the i2c bus type can use the generic subsystem-level runtime PM callbacks. For these reasons, rework the system sleep PM callbacks provided by the i2c bus type to handle hibernation correctly and to invoke the "legacy" callbacks for drivers that provide them. In addition to that make the i2c bus type use the generic subsystem-level runtime PM callbacks. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Jean Delvare <khali@linux-fr.org>
| * | Merge branch 'devel-stable' into develRussell King2010-05-1734-44/+113
| |\ \ | | |/ | | | | | | | | | | | | | | | Conflicts: arch/arm/Kconfig arch/arm/include/asm/system.h arch/arm/mm/Kconfig
| | * i2c-core: Use per-adapter userspace device listsJean Delvare2010-05-041-16/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using a single list for all userspace devices leads to a dead lock on multiplexed buses in some circumstances (mux chip instantiated from userspace). This is solved by using a separate list for each bus segment. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Michael Lawnick <ml.lawnick@gmx.de>
| | * i2c: Fix probing of FSC hardware monitoring chipsJean Delvare2010-05-041-5/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some FSC hardware monitoring chips (Syleus at least) doesn't like quick writes we typically use to probe for I2C chips. Use a regular byte read instead for the address they live at (0x73). These are the only known chips living at this address on PC systems. For clarity, this fix should not be needed for kernels 2.6.30 and later, as we started instantiating the hwmon devices explicitly based on DMI data. Still, this fix is valuable in the following two cases: * Support for recent FSC chips on older kernels. The DMI-based device instantiation is more difficult to backport than the device support itself. * Case where the DMI-based device instantiation fails, whatever the reason. We fall back to probing in that case, so it should work. This fixes kernel bug #15634: https://bugzilla.kernel.org/show_bug.cgi?id=15634 Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Cc: stable@kernel.org
| | * i2c-core: Erase pointer to clientdata on removalWolfram Sang2010-05-041-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After discovering that a lot of i2c-drivers leave the pointer to their clientdata dangling, it was decided to let the core handle this issue. It is assumed that the core may access the private data after remove() as there are no guarantees for the lifetime of such pointers anyhow (see thread starting at http://lkml.org/lkml/2010/3/21/68) Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
| | * I2C: Fix section mismatch errors in i2c-octeon.cDavid Daney2010-04-301-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: David Daney <ddaney@caviumnetworks.com> To: linux-i2c@vger.kernel.org To: ben-linux@fluff.org To: khali@linux-fr.org Cc: linux-mips@linux-mips.org Cc: rade.bozic.ext@nsn.com Patchwork: http://patchwork.linux-mips.org/patch/1037/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
| | * i2c-stu300: off by one issueDan Carpenter2010-04-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | If we don't find the correct rate, we want to end the loop with "i" pointing to the last element in the array. Signed-off-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
| | * i2c-pnx: Add stop conditions for end of transferKevin Wells2010-04-201-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | Add a stop condition bit flag to the last byte in the transfer. This will generate an extra clock to handle the stop condition and prevent devices from staying in an ACK'd state. Signed-off-by: Kevin Wells <wellsk40@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
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