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path: root/drivers/i2c
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2008-09-05Merge branch 'sh/for-2.6.27' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6 * 'sh/for-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: i2c: fix i2c-sh_mobile timing issues sh64: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y. sh: resume_kernel fix for kernel oops built with CONFIG_BKL_PREEMPT=y. sh: fix semtimedop syscall sh: update AP325RXA defconfig sh: update Migo-R defconfig sh: fix platform_resource_setup_memory() section mismatch sh: fix kexec entry point for crash kernels sh: crash kernel resource fix sh: fix ptrace_64.c:user_disable_single_step() sh64: re-add the __strnlen_user() prototype
2008-09-05i2c: fix i2c-sh_mobile timing issuesMagnus Damm
This patch teaches the i2c-sh_mobile driver to make use of wait irqs. Without this patch only dte irqs are used which may lead to overruns and cases of missing stop and extra bytes being read on the i2c bus. Use of wait irqs forces the hardware to pause and wait until the cpu is ready. Polling is also reworked in this patch to fix ms delay issues. Verified with bus analyzer and tested on MigoR and AP325RXA boards. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-08-28i2c: Prevent log spam on some DVB adaptersJean Delvare
Some DVB adapters do not support the special I2C transaction that we use for probing purposes. There's no point in logging this event, as there's nothing the user can do and in general there is no actual problem. So, degrade one of these messages to a debug message, and move the other one around so that it is only printed on bogus drivers. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Uwe Bugla <uwe.bugla@gmx.de>
2008-08-28i2c: Fix device_init_wakeup placeMarc Pignat
device_init_wakeup must be called after device_register. Signed-off-by: Marc Pignat <marc.pignat@hevs.ch> Acked-by: David Brownell <david-b@pacbell.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-08-23removed unused #include <linux/version.h>'sAdrian Bunk
This patch lets the files using linux/version.h match the files that #include it. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-14USB: isp1301: fix compilationDmitry Baryshkov
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-08-10i2c: correct some size_t printk formatsDavid Brownell
Fix various printk format strings where %zd was passed a size_t; those should be %zu instead. (Courtesy of a version of GCC which warns when these details are wrong.) Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-08-10i2c: Check for address business before creating clientsJean Delvare
We check for address business in i2c_probe_address(), i2c_detect_address() and i2c_new_probed_device(), but this isn't sufficient. Drivers can call i2c_attach_client() and i2c_new_device() on any address, so we must check the address there as well. This fixes bug #11239: http://bugzilla.kernel.org/show_bug.cgi?id=11239 Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-08-10i2c: Let users select algorithm drivers manually againJean Delvare
In kernel 2.6.26, the ability to select I2C algorithm drivers manually was removed, as all in-kernel drivers do that automatically. However there were some complaints that it was a problem for out-of-tree I2C bus drivers. In order to address these complaints, let's allow manual selection of these drivers again, but still hide them by default for better general user experience. This closes bug #11140: http://bugzilla.kernel.org/show_bug.cgi?id=11140 Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-08-10i2c: Fix NULL pointer dereference in i2c_new_probed_deviceHans Verkuil
Fix a NULL pointer dereference that happened when calling i2c_new_probed_device on one of the addresses for which we use byte reads instead of quick write for detection purpose (that is: 0x30-0x37 and 0x50-0x5f). Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-08-10i2c: Fix oops on bus multiplexer driver loadingJean Delvare
The two I2C bus multiplexer drivers (i2c-amd756-s4882 and i2c-nforce2-s4985) make use of the bus they want to multiplex before checking if it is really present. Swap the instructions to test for presence first. This fixes a oops reported by Ingo Molnar. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Ingo Molnar <mingo@elte.hu>
2008-08-07[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/machRussell King
This just leaves include/asm-arm/plat-* to deal with. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixesRussell King
2008-08-07[ARM] Remove asm/hardware.h, use asm/arch/hardware.h insteadRussell King
Remove includes of asm/hardware.h in addition to asm/arch/hardware.h. Then, since asm/hardware.h only exists to include asm/arch/hardware.h, update everything to directly include asm/arch/hardware.h and remove asm/hardware.h. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07[ARM] Eliminate useless includes of asm/mach-types.hRussell King
There are 43 includes of asm/mach-types.h by files that don't reference anything from that file. Remove these unnecessary includes. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-07-28i2c: Blackfin I2C Driver: Functional power management supportMichael Hennerich
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>
2008-07-28i2c: S3C24XX I2C frequency scaling support.Ben Dooks
Add support for CPU frequency scaling to the S3C24XX I2C driver. Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-28i2c: i2c_gpio: keep probe resident for hotplugged devices.Ben Dooks
Change the i2c_gpio driver to use platform_driver_register() instead of platform_driver_probe() to ensure that is can attach to any devices that may be loaded after it has initialised. Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-28i2c: S3C2410: Pass the I2C bus number via drivers platform dataBen Dooks
Allow the platform data to specify the bus bumber that the new I2C bus will be given. This is to allow the use of the board registration mechanism to specify the new style of I2C device registration which allows boards to provide a list of attached devices. Note, as discussed on the mailing list, we have dropped backwards compatibility of adding an dynamic bus number as it should not affect most boards to have the bus pinned to 0 if they have either not specified platform data for driver. Any board supplying platform data will automatically have the bus_num field set to 0, and anyone who needs the driver on a different bus number can supply platform data to set bus_num. Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2008-07-25gpiolib: allow user-selectionMichael Buesch
This patch adds functionality to the gpio-lib subsystem to make it possible to enable the gpio-lib code even if the architecture code didn't request to get it built in. The archtitecture code does still need to implement the gpiolib accessor functions in its asm/gpio.h file. This patch adds the implementations for x86 and PPC. With these changes it is possible to run generic GPIO expansion cards on every architecture that implements the trivial wrapper functions. Support for more architectures can easily be added. Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: David Brownell <david-b@pacbell.net> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jean Delvare <khali@linux-fr.org> Cc: Samuel Ortiz <sameo@openedhand.com> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25gpio: sysfs interfaceDavid Brownell
This adds a simple sysfs interface for GPIOs. /sys/class/gpio /export ... asks the kernel to export a GPIO to userspace /unexport ... to return a GPIO to the kernel /gpioN ... for each exported GPIO #N /value ... always readable, writes fail for input GPIOs /direction ... r/w as: in, out (default low); write high, low /gpiochipN ... for each gpiochip; #N is its first GPIO /base ... (r/o) same as N /label ... (r/o) descriptive, not necessarily unique /ngpio ... (r/o) number of GPIOs; numbered N .. N+(ngpio - 1) GPIOs claimed by kernel code may be exported by its owner using a new gpio_export() call, which should be most useful for driver debugging. Such exports may optionally be done without a "direction" attribute. Userspace may ask to take over a GPIO by writing to a sysfs control file, helping to cope with incomplete board support or other "one-off" requirements that don't merit full kernel support: echo 23 > /sys/class/gpio/export ... will gpio_request(23, "sysfs") and gpio_export(23); use /sys/class/gpio/gpio-23/direction to (re)configure it, when that GPIO can be used as both input and output. echo 23 > /sys/class/gpio/unexport ... will gpio_free(23), when it was exported as above The extra D-space footprint is a few hundred bytes, except for the sysfs resources associated with each exported GPIO. The additional I-space footprint is about two thirds of the current size of gpiolib (!). Since no /dev node creation is involved, no "udev" support is needed. Related changes: * This adds a device pointer to "struct gpio_chip". When GPIO providers initialize that, sysfs gpio class devices become children of that device instead of being "virtual" devices. * The (few) gpio_chip providers which have such a device node have been updated. * Some gpio_chip drivers also needed to update their module "owner" field ... for which missing kerneldoc was added. * Some gpio_chips don't support input GPIOs. Those GPIOs are now flagged appropriately when the chip is registered. Based on previous patches, and discussion both on and off LKML. A Documentation/ABI/testing/sysfs-gpio update is ready to submit once this merges to mainline. [akpm@linux-foundation.org: a few maintenance build fixes] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-22Driver Core: add ability for class_for_each_device to start in middle of listGreg Kroah-Hartman
This mirrors the functionality that driver_for_each_device has as well. We add a start variable, and all callers of the function are fixed up at the same time. The block layer will be using this new functionality in a follow-on patch. Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-22device create: i2c: convert device_create to device_create_drvdataGreg Kroah-Hartman
device_create() is race-prone, so use the race-free device_create_drvdata() instead as device_create() is going away. Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-07-16i2c: Convert the max6875 driver to a new-style i2c driverJean Delvare
The new-style max6875 driver implements the optional detect() callback to cover the use cases of the legacy driver. I'm curious if anyone really needs this though, so it might be removed in the feature. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-16i2c: Convert the pca9539 driver to a new-style i2c driverJean Delvare
The new-style pca9539 driver implements the optional detect() callback to cover the use cases of the legacy driver. Warning: users will now have to use the force module parameter to get the driver to attach to their device. That's not a bad thing as these devices can't be detected anyway. Note that this doesn't change the fact that this driver is deprecated in favor of gpio/pca953x. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-16i2c: Convert the pcf8575 driver to a new-style i2c driverJean Delvare
The new-style pcf8575 driver implements the optional detect() callback to cover the use cases of the legacy driver. Warning: users will now have to use the force module parameter to get the driver to attach to their device. That's not a bad thing as these devices can't be detected anyway. Note that this doesn't change the fact that this driver is deprecated in favor of gpio/pcf857x. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-16i2c: Convert the pcf8574 driver to a new-style i2c driverJean Delvare
The new-style pcf8574 driver implements the optional detect() callback to cover the use cases of the legacy driver. Warning: users will now have to use the force module parameter to get the driver to attach to their device. That's not a bad thing as these devices can't be detected anyway. Note that this doesn't change the fact that this driver is deprecated in favor of gpio/pcf857x. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-16i2c: Convert the pcf8591 driver to a new-style i2c driverJean Delvare
The new-style pcf8591 driver implements the optional detect() callback to cover the use cases of the legacy driver. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-16i2c: Convert the eeprom driver to a new-style i2c driverJean Delvare
The new-style eeprom driver implements the optional detect() callback to cover the use cases of the legacy driver. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-16i2c: Clear i2c_adapter.dev on adapter removalJean Delvare
Clear i2c_adapter.dev on adapter removal. This makes it possible to re-add the adapter at a later point, which some drivers (i2c-amd756-s4882, i2c-nforce2-s4985) actually do. This fixes a bug reported by John Stultz here: http://lkml.org/lkml/2008/7/15/720 and by Ingo Molar there: http://lkml.org/lkml/2008/7/16/78 Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: John Stultz <johnstul@us.ibm.com> Cc: Ingo Molnar <mingo@elte.hu>
2008-07-16Merge commit 'origin/master'Benjamin Herrenschmidt
Manual merge of: arch/powerpc/Kconfig arch/powerpc/kernel/stacktrace.c arch/powerpc/mm/slice.c arch/ppc/kernel/smp.c
2008-07-15Merge branch 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6Linus Torvalds
* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6: (56 commits) i2c: Add detection capability to new-style drivers i2c: Call client_unregister for new-style devices too i2c: Clean up old chip drivers i2c-ibm_iic: Register child nodes i2c: New-style EEPROM driver using device IDs i2c: Export the i2c_bus_type symbol i2c-au1550: Fix PM support i2c-dev: Delete empty detach_client callback i2c: Drop stray references to lm_sensors i2c: Check for ACPI resource conflicts i2c-ocores: basic PM support i2c-sibyte: SWARM I2C board initialization i2c-i801: Fix handling of error conditions i2c-i801: Rename local variable temp to status i2c-i801: Properly report bus arbitration loss i2c-i801: Remove verbose debugging messages i2c-algo-pcf: Drop unused struct members i2c-algo-pcf: Multi-master lost-arbitration improvement i2c: Deprecate the legacy gpio drivers i2c-pxa: Initialize early ...
2008-07-15Merge commit '85082fd7cbe3173198aac0eb5e85ab1edcc6352c' into test-buildBenjamin Herrenschmidt
Manual fixup of: arch/powerpc/Kconfig
2008-07-15Merge commit 'gcl/gcl-next'Benjamin Herrenschmidt
2008-07-14Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (241 commits) [ARM] 5171/1: ep93xx: fix compilation of modules using clocks [ARM] 5133/2: at91sam9g20 defconfig file [ARM] 5130/4: Support for the at91sam9g20 [ARM] 5160/1: IOP3XX: gpio/gpiolib support [ARM] at91: Fix NAND FLASH timings for at91sam9x evaluation kits. [ARM] 5084/1: zylonite: Register AC97 device [ARM] 5085/2: PXA: Move AC97 over to the new central device declaration model [ARM] 5120/1: pxa: correct platform driver names for PXA25x and PXA27x UDC drivers [ARM] 5147/1: pxaficp_ir: drop pxa_gpio_mode calls, as pin setting [ARM] 5145/1: PXA2xx: provide api to control IrDA pins state [ARM] 5144/1: pxaficp_ir: cleanup includes [ARM] pxa: remove pxa_set_cken() [ARM] pxa: allow clk aliases [ARM] Feroceon: don't disable BPU on boot [ARM] Orion: LED support for HP mv2120 [ARM] Orion: add RD88F5181L-FXO support [ARM] Orion: add RD88F5181L-GE support [ARM] Orion: add Netgear WNR854T support [ARM] s3c2410_defconfig: update for current build [ARM] Acer n30: Minor style and indentation fixes. ...
2008-07-14[ARM] Merge most of the PXA work for initial mergeRussell King
This includes PXA work up to the SPI changes for the initial merge, since e172274ccc55d20536fbdceb6131f38e288541e0 depends on the SPI tree being merged. Conflicts: arch/arm/configs/em_x270_defconfig arch/arm/configs/xm_x270_defconfig
2008-07-14Merge commit 'v2.6.26' into bkl-removalJonathan Corbet
2008-07-14i2c: Add detection capability to new-style driversJean Delvare
Add a mechanism to let new-style i2c drivers optionally autodetect devices they would support on selected buses and ask i2c-core to instantiate them. This is a replacement for legacy i2c drivers, much cleaner. Where drivers had to implement both a legacy i2c_driver and a new-style i2c_driver so far, this mechanism makes it possible to get rid of the legacy i2c_driver and implement both enumerated and detected device support with just one (new-style) i2c_driver. Here is a quick conversion guide for these drivers, step by step: * Delete the legacy driver definition, registration and removal. Delete the attach_adapter and detach_client methods of the legacy driver. * Change the prototype of the legacy detect function from static int foo_detect(struct i2c_adapter *adapter, int address, int kind); to static int foo_detect(struct i2c_client *client, int kind, struct i2c_board_info *info); * Set the new-style driver detect callback to this new function, and set its address_data to &addr_data (addr_data is generally provided by I2C_CLIENT_INSMOD.) * Add the appropriate class to the new-style driver. This is typically the class the legacy attach_adapter method was checking for. Class checking is now mandatory (done by i2c-core.) See <linux/i2c.h> for the list of available classes. * Remove the i2c_client allocation and freeing from the detect function. A pre-allocated client is now handed to you by i2c-core, and is freed automatically. * Make the detect function fill the type field of the i2c_board_info structure it was passed as a parameter, and return 0, on success. If the detection fails, return -ENODEV. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c: Call client_unregister for new-style devices tooJean Delvare
We call adapter->client_register for both legacy and new-style i2c devices, however we only call adapter->client_unregister for legacy drivers. This doesn't make much sense. Usually, drivers will undo in client_unregister what they did in client_register, so we should call neither or both for every given i2c device. In order to ease the transition from legacy to new-style devices, it seems preferable to actually call both. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: David Brownell <david-b@pacbell.net>
2008-07-14i2c: Clean up old chip driversJean Delvare
Clean up old i2c chip drivers: * Name the i2c_client "client" instead of "new_client". * Drop useless initializations to 0. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c-ibm_iic: Register child nodesSean MacLennan
This patch completes the conversion of the IBM IIC driver to an of-platform driver. It removes the index from the IBM IIC driver and makes it an unnumbered driver. It then calls of_register_i2c_devices to properly register all the child nodes in the DTS. Signed-off-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c: New-style EEPROM driver using device IDsWolfram Sang
Add a new-style driver for most I2C EEPROMs, giving sysfs read/write access to their data. Tested with various chips and clock rates. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c: Export the i2c_bus_type symbolJon Smirl
Export the root of the i2c bus so that PowerPC device tree code can iterate over devices on the i2c bus. Signed-off-by: Jon Smirl <jonsmirl@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c-au1550: Fix PM supportManuel Lauss
Fix driver power management: - suspend the PSC while driver is idle. - move PSC init/deinit to separate functions, as PSC must be initialized/shutdown on resume/suspend. Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c-dev: Delete empty detach_client callbackJean Delvare
Implementing detach_client is optional, so there is no point in an empty implementation. Likewise, i2c driver IDs are optional, and we don't need one. Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c: Drop stray references to lm_sensorsJean Delvare
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c: Check for ACPI resource conflictsJean Delvare
Check for ACPI resource conflicts in i2c bus drivers. I've included all recent SMBus master drivers for PC hardware. I've voluntarily left out: * Drivers that don't run on PCs: they can't conflict with ACPI. * Bit-banged bus device drivers: it's very unlikely that ACPI would deal with such buses. Signed-off-by: Jean Delvare <jdelvare@suse.de>
2008-07-14i2c-ocores: basic PM supportManuel Lauss
Basic PM support: reinit the core on resume, disable it on suspend. Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net> Acked-by: Peter Korsgaard <jacmet@sunsite.dk> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c-sibyte: SWARM I2C board initializationMaciej W. Rozycki
The standard rtc-m41t80.c driver cannot be used with the SWARM as it is, because the board does not provide setup information for the I2C core. As a result the bus and the address to probe for the M41T80 chip is not known. Here is a set of changes that fix the problem: 1. swarm-i2c.c -- SWARM I2C board setup, currently for the M41T80 chip on the bus #1 only (there is a MAX6654 temperature sensor on the bus #0 which may be added in the future if we have a driver for that chip). 2. The i2c-sibyte.c BCM1250A SMBus controller driver now registers its buses as numbered so that board setup is correctly applied. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2008-07-14i2c-i801: Fix handling of error conditionsJean Delvare
Move the check of pre-transaction and post-transaction conditions to separate functions, and adjust them a bit. Having dedicated functions for that ensures that errors are handled in a consistent way. Bit HOST_BUSY of the status register is read-only, so writing to it is certainly not going to clear it. If this bit is set then we simply don't want to start the transaction, as it means that somebody else (ACPI, SMM?) is already using the controller. Signed-off-by: Jean Delvare <khali@linux-fr.org>