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2016-11-24i2c: use an IRQ to report Host Notify events, not alertBenjamin Tissoires
The current SMBus Host Notify implementation relies on .alert() to relay its notifications. However, the use cases where SMBus Host Notify is needed currently is to signal data ready on touchpads. This is closer to an IRQ than a custom API through .alert(). Given that the 2 touchpad manufacturers (Synaptics and Elan) that use SMBus Host Notify don't put any data in the SMBus payload, the concept actually matches one to one. Benefits are multiple: - simpler code and API: the client will just have an IRQ, and nothing needs to be added in the adapter beside internally enabling it. - no more specific workqueue, the threading is handled by IRQ core directly (when required) - no more races when removing the device (the drivers are already required to disable irq on remove) - simpler handling for drivers: use plain regular IRQs - no more dependency on i2c-smbus for i2c-i801 (and any other adapter) - the IRQ domain is created automatically when the adapter exports the Host Notify capability - the IRQ are assign only if ACPI, OF and the caller did not assign one already - the domain is automatically destroyed on remove - fewer lines of code (minus 20, yeah!) Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24i2c: i801: remove SMBNTFDDAT reads as they always seem to return 0Benjamin Tissoires
On the platform tested, reading SMBNTFDDAT always returns 0 (using 1 read of a word or 2 of 2 bytes). Given that we are not sure why and that we don't need to rely on the data parameter in the current users of Host Notify, remove this part of the code. If someone wants to re-enable it, just revert this commit and data should be available. Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24i2c: i801: use the BIT() macro for FEATURES_* alsoBenjamin Tissoires
no functional changes Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24i2c: i801: use BIT() macro for bits definitionBenjamin Tissoires
i801 mixes hexadecimal and decimal values for defining bits. However, we have a nice BIT() macro for this exact purpose. No functional changes, cleanup only. Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24i2c: i801: minor formatting issuesBenjamin Tissoires
No functional changes, just typos and remove unused #define. Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24i2c: i801: store and restore the SLVCMD register at load and unloadBenjamin Tissoires
Also do not override any other configuration in this register. Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24i2c: mlxcpld: add master driver for mellanox systemsVadim Pasternak
Device driver for Mellanox I2C controller logic, implemented in Lattice CPLD device. Device supports: - Master mode - One physical bus - Polling mode The Kconfig currently controlling compilation of this code is: drivers/i2c/busses/Kconfig:config I2C_MLXCPLD Signed-off-by: Michael Shych <michaelsh@mellanox.com> Signed-off-by: Vadim Pasternak <vadimp@mellanox.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24i2c: designware: fix rx fifo depth trackingRussell King
When loading the TX fifo to receive bytes on the I2C bus, we incorrectly count the number of bytes: rx_limit = dev->rx_fifo_depth - dw_readl(dev, DW_IC_RXFLR); while (buf_len > 0 && tx_limit > 0 && rx_limit > 0) { if (rx_limit - dev->rx_outstanding <= 0) break; rx_limit--; dev->rx_outstanding++; } DW_IC_RXFLR indicates how many bytes are available to be read in the FIFO, dev->rx_fifo_depth is the FIFO size, and dev->rx_outstanding is the number of bytes that we've requested to be read so far, but which have not been read. Firstly, increasing dev->rx_outstanding and decreasing rx_limit and then comparing them results in each byte consuming "two" bytes in this tracking, so this is obviously wrong. Secondly, the number of bytes that _could_ be received into the FIFO at any time is the number of bytes we have so far requested but not yet read from the FIFO - in other words dev->rx_outstanding. So, in order to request enough bytes to fill the RX FIFO, we need to request dev->rx_fifo_depth - dev->rx_outstanding bytes. Modifying the code thusly results in us reaching the maximum number of bytes outstanding each time we queue more "receive" operations, provided the transfer allows that to happen. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-24i2c: designware: report short transfersRussell King
Rather than reporting success for a short transfer due to interrupt latency, report an error both to the caller, as well as to the kernel log. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-19i2c: i2c-mux-pca954x: fix deselect enabling for device-treeAlex Hemme
Deselect functionality can be ignored for device-trees with "i2c-mux-idle-disconnect" entries if no platform_data is available. By enabling the deselect functionality outside the platform_data block the logic works as it did in previous kernels. Fixes: 7fcac9807175 ("i2c: i2c-mux-pca954x: convert to use an explicit i2c mux core") Cc: <stable@vger.kernel.org> # v4.7+ Signed-off-by: Alex Hemme <ahemme@cisco.com> Signed-off-by: Ziyang Wu <ziywu@cisco.com> [touched up a few minor issues /peda] Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-18i2c: xlp9xx: ACPI support for I2C clientsTanmay Jagdale
The ACPI companion of the adapter has to be set for I2C controller code to read and attach the slave devices described in the ACPI table with the I2CSerialBus resource descriptor. Used ACPI_COMPANION_SET macro to set this. Signed-off-by: Tanmay Jagdale <tanmay.jagdale@broadcom.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-18i2c: uniphier-f: rename jump label to follow coding style guidelineMasahiro Yamada
Documentation/CodingStyle recommends to use label names which say what the goto does or why the goto exists. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-18i2c: uniphier: rename jump label to follow coding style guidelineMasahiro Yamada
Documentation/CodingStyle recommends to use label names which say what the goto does or why the goto exists. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-18i2c: designware: Allow reduce bus speed by "clock-frequency" propertyJarkko Nikula
Allow more flexibility to bus speed selection. Now if there are I2C slave connections defined in ACPI the speed of slowest device on the bus will define the bus speed. However if also "clock-frequency" device property is defined we should use the slowest of these two. This is targeted to maker boards where developer may want to connect slower I2C slave devices to the bus than defined in existing ACPI I2C slave connections. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-18i2c: designware: Implement support for SMBus block read and writeTin Huynh
Free and Open IPMI use SMBUS BLOCK Read/Write to support SSIF protocol. However, I2C Designware Core Driver doesn't handle the case at the moment. The below patch supports this feature. Signed-off-by: Tin Huynh <tnhuynh@apm.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-18i2c: constify i2c_adapter_quirks structuresJulia Lawall
Check for i2c_adapter_quirks structures that are only stored in the quirks field of an i2c_adapter structure. This field is declared const, so i2c_adapter_quirks structures that have this property can be declared as const also. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Acked-by: Ray Jui <ray.jui@broadcom.com> # for bcm-iproc Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-18i2c: digicolor: use clk_disable_unprepare instead of clk_unprepareWei Yongjun
since clk_prepare_enable() is used to get i2c->clk, we should use clk_disable_unprepare() to release it for the error path. Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-18i2c: i2c-pxa-pci; make explicitly non-modularPaul Gortmaker
The Kconfig currently controlling compilation of this code is: drivers/i2c/busses/Kconfig:config I2C_PXA_PCI drivers/i2c/busses/Kconfig: def_bool I2C_PXA && X86_32 && PCI && OF ...meaning that it currently is not being built as a module by anyone. Lets remove the modular code that is essentially orphaned, so that when reading the driver there is no doubt it is builtin-only. We explicitly disallow a driver unbind, since that doesn't have a sensible use case anyway, and it allows us to drop the ".remove" code for non-modular drivers. Since module_pci_driver() uses the same init level priority as builtin_pci_driver() the init ordering remains unchanged with this commit. Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code. We also delete the MODULE_LICENSE tag etc. since all that information was (or is now) contained at the top of the file in the comments. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17i2c: mux: mellanox: add driverVadim Pasternak
This driver allows I2C routing controlled through CPLD select registers on a wide range of Mellanox systems (CPLD Lattice device). MUX selection is provided by digital and analog HW. Analog part is not under SW control. Digital part is under CPLD control (channel selection/de-selection). Connectivity schema. .---. .-------------. | l | | |-- i2cx1 -- i2cx8 | i |-- i2cn --+--| mlxcpld mux | | n | | | |-- i2cy1 -- i2cy8 | u | | '-------------' | x | | | '---' '---------' i2c-mux-mlxpcld does not necessarily require i2c-mlxcpld. It can be used along with another bus driver, and still control i2c routing through CPLD mux selection, in case the system is equipped with CPLD capable of mux selection control. The Kconfig currently controlling compilation of this code is: drivers/i2c/muxes/Kconfig:config I2C_MUX_MLXCPLD Signed-off-by: Michael Shych <michaelsh@mellanox.com> Signed-off-by: Vadim Pasternak <vadimp@mellanox.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Acked-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17i2c: Provide a temporary .probe_new() call-back typeLee Jones
This will aid the seamless removal of the current probe()'s, more commonly unused than used second parameter. Most I2C drivers can simply switch over to the new interface, others which have DT support can use its own matching instead and others can call i2c_match_id() themselves. This brings I2C's device probe method into line with other similar interfaces in the kernel and prevents the requirement to pass an i2c_device_id table. Suggested-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> [Kieran: fix rebase conflicts and adapt for dev_pm_domain_{attach,detach}] Tested-by: Kieran Bingham <kieran@bingham.xyz> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Kieran Bingham <kieran@bingham.xyz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17i2c: Export i2c_match_id() for direct use by device driversLee Jones
When there was no other way to match a I2C device to driver i2c_match_id() was exclusively used. However, now there are other types of tables which are commonly supplied, matching on an i2c_device_id table is used less frequently. Instead of _always_ calling i2c_match_id() from within the framework, we only need to do so from drivers which have no other way of matching. This patch makes i2c_match_id() available to the aforementioned device drivers. Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Tested-by: Kieran Bingham <kieran@bingham.xyz> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Kieran Bingham <kieran@bingham.xyz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17i2c: Make I2C ID tables non-mandatory for DT'ed devicesLee Jones
Currently the I2C framework insists on devices supplying an I2C ID table. Many of the devices which do so unnecessarily adding quite a few wasted lines to kernel code. This patch allows drivers a means to 'not' supply the aforementioned table and match on DT match tables instead. Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Tested-by: Kieran Bingham <kieran@bingham.xyz> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Kieran Bingham <kieran@bingham.xyz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17i2c: Match using traditional OF methods, then by vendor-less compatible stringsLee Jones
This function provides a single call for all I2C devices which need to match firstly using traditional OF means i.e by of_node, then if that fails we attempt to match using the supplied I2C client name with a list of supplied compatible strings with the '<vendor>,' string removed. The latter is required due to the unruly naming conventions used currently by I2C devices. Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> [Kieran: Fix static inline usage on !CONFIG_OF] Tested-by: Kieran Bingham <kieran@bingham.xyz> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Kieran Bingham <kieran@bingham.xyz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-17i2c: Add the ability to match device to compatible string without an of_nodeLee Jones
A great deal of I2C devices are currently matched via DT node name, and as such the compatible naming convention of '<vendor>,<device>' has gone somewhat awry - some nodes don't supply one, some supply an arbitrary string and others the correct device name with an arbitrary vendor prefix. In an effort to correct this problem we have to supply a mechanism to match a device by compatible string AND by simple device name. This function strips off the '<vendor>,' part of a supplied compatible string and attempts to match without it. It is also used for sysfs, where a user can choose to instantiate a device on an i2c bus using the sysfs interface by providing a string and address to match and communicate with the device on the bus. Presently this string is only matched against the old i2c device id style strings, even in the presence of full device tree compatible strings with vendor prefixes. Providing a vendor-prefixed string to the sysfs interface will not match against the device tree of_match_device() calls as there is no device tree node to parse from the sysfs interface. This function can match both vendor prefixed and stripped compatible strings on the sysfs interface. Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Kieran Bingham <kieran@bingham.xyz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-14i2c: mux: fix up dependenciesLinus Walleij
We get the following build error from UM Linux after adding an entry to drivers/iio/gyro/Kconfig that issues "select I2C_MUX": ERROR: "devm_ioremap_resource" [drivers/i2c/muxes/i2c-mux-reg.ko] undefined! ERROR: "of_address_to_resource" [drivers/i2c/muxes/i2c-mux-reg.ko] undefined! It appears that the I2C mux core code depends on HAS_IOMEM for historical reasons, while CONFIG_I2C_MUX_REG does *not* have a direct dependency on HAS_IOMEM. This creates a situation where a allyesconfig or allmodconfig for UM Linux will select I2C_MUX, and will implicitly enable I2C_MUX_REG as well, and the compilation will fail for the register driver. Fix this up by making I2C_MUX_REG depend on HAS_IOMEM and removing the dependency from I2C_MUX. Reported-by: kbuild test robot <fengguang.wu@intel.com> Reported-by: Jonathan Cameron <jic23@jic23.retrosnub.co.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Jonathan Cameron <jic23@kernel.org> Acked-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2016-11-13i2c: Add pointer dereference protection to i2c_match_id()Lee Jones
Here we're providing dereference protection for i2c_match_id(), which saves us having to do it each time it's called. We're also stripping out the (now) needless checks in i2c_device_match(). This patch paves the way for other, similar code trimming. Acked-by: Grant Likely <grant.likely@linaro.org> Signed-off-by: Lee Jones <lee.jones@linaro.org> Tested-by: Kieran Bingham <kieran@bingham.xyz> Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com> Tested-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Kieran Bingham <kieran@bingham.xyz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-10i2c: mux: demux-pinctrl: make drivers with no pinctrl work againWolfram Sang
Some drivers like i2c-gpio do not have dedicated pinctrl states. They broke when error checking for pinctrl was added. Detect them now, and in their case, simply skip over pinctrl configuration. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-07i2c: bcm2835: Add support for dynamic clockNoralf Trønnes
Support a dynamic clock by reading the frequency and setting the divisor in the transfer function instead of during probe. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Reviewed-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-07i2c: bcm2835: Support i2c-dev ioctl I2C_TIMEOUTNoralf Trønnes
Use i2c_adapter->timeout for the completion timeout value. The core default is 1 second. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-07i2c: bcm2835: Add support for Repeated Start ConditionNoralf Trønnes
Documentation/i2c/i2c-protocol states that Combined transactions should separate messages with a Start bit and end the whole transaction with a Stop bit. This patch adds support for issuing only a Start between messages instead of a Stop followed by a Start. This implementation differs from downstream i2c-bcm2708 in 2 respects: - it uses an interrupt to detect that the transfer is active instead of using polling. There is no interrupt for Transfer Active, but by not prefilling the FIFO it's possible to use the TXW interrupt. - when resetting/disabling the controller between transfers it writes CLEAR to the control register instead of just zero. Using just zero gave many errors. This might be the reason why downstream had to disable this feature and make it available with a module parameter. I have run thousands of transfers to a DS1307 (rtc), MMA8451 (accel) and AT24C32 (eeprom) in parallel without problems. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Acked-by: Eric Anholt <eric@anholt.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-07i2c: bcm2835: Can't support I2C_M_IGNORE_NAKNoralf Trønnes
The controller can't support this flag, so remove it. Documentation/i2c/i2c-protocol states that all of the message is sent: I2C_M_IGNORE_NAK: Normally message is interrupted immediately if there is [NA] from the client. Setting this flag treats any [NA] as [A], and all of message is sent. >From the BCM2835 ARM Peripherals datasheet: The ERR field is set when the slave fails to acknowledge either its address or a data byte written to it. So when the controller doesn't receive an ack, it sets ERR and raises an interrupt. In other words, the whole message is not sent. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-07i2c: bcm2835: Use dev_dbg logging on transfer errorsNoralf Trønnes
Writing to an AT24C32 generates on average 2x i2c transfer errors per 32-byte page write. Which amounts to a lot for a 4k write. This is due to the fact that the chip doesn't respond during it's internal write cycle when the at24 driver tries and retries the next write. Only a handful drivers use dev_err() on transfer error, so switch to dev_dbg() instead. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-07i2c: bcm2835: Protect against unexpected TXW/RXR interruptsNoralf Trønnes
If an unexpected TXW or RXR interrupt occurs (msg_buf_remaining == 0), the driver has no way to fill/drain the FIFO to stop the interrupts. In this case the controller has to be disabled and the transfer completed to avoid hang. (CLKT | ERR) and DONE interrupts are completed in their own paths, and the controller is disabled in the transfer function after completion. Unite the code paths and do disabling inside the interrupt routine. Clear interrupt status bits in the united completion path instead of trying to do it on every interrupt which isn't necessary. Only CLKT, ERR and DONE can be cleared that way. Add the status value to the error value in case of TXW/RXR errors to distinguish them from the other S_LEN error. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-07i2c: bcm2835: Fix hang for writing messages larger than 16 bytesNoralf Trønnes
Writing messages larger than the FIFO size results in a hang, rendering the machine unusable. This is because the RXD status flag is set on the first interrupt which results in bcm2835_drain_rxfifo() stealing bytes from the buffer. The controller continues to trigger interrupts waiting for the missing bytes, but bcm2835_fill_txfifo() has none to give. In this situation wait_for_completion_timeout() apparently is unable to stop the madness. The BCM2835 ARM Peripherals datasheet has this to say about the flags: TXD: is set when the FIFO has space for at least one byte of data. RXD: is set when the FIFO contains at least one byte of data. TXW: is set during a write transfer and the FIFO is less than full. RXR: is set during a read transfer and the FIFO is or more full. Implementing the logic from the downstream i2c-bcm2708 driver solved the hang problem. Signed-off-by: Noralf Trønnes <noralf@tronnes.org> Reviewed-by: Eric Anholt <eric@anholt.net> Reviewed-by: Martin Sperl <kernel@martin.sperl.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-11-04i2c: core: fix NULL pointer dereference under race conditionVladimir Zapolskiy
Race condition between registering an I2C device driver and deregistering an I2C adapter device which is assumed to manage that I2C device may lead to a NULL pointer dereference due to the uninitialized list head of driver clients. The root cause of the issue is that the I2C bus may know about the registered device driver and thus it is matched by bus_for_each_drv(), but the list of clients is not initialized and commonly it is NULL, because I2C device drivers define struct i2c_driver as static and clients field is expected to be initialized by I2C core: i2c_register_driver() i2c_del_adapter() driver_register() ... bus_add_driver() ... ... bus_for_each_drv(..., __process_removed_adapter) ... i2c_do_del_adapter() ... list_for_each_entry_safe(..., &driver->clients, ...) INIT_LIST_HEAD(&driver->clients); To solve the problem it is sufficient to do clients list head initialization before calling driver_register(). The problem was found while using an I2C device driver with a sluggish registration routine on a bus provided by a physically detachable I2C master controller, but practically the oops may be reproduced under the race between arbitraty I2C device driver registration and managing I2C bus device removal e.g. by unbinding the latter over sysfs: % echo 21a4000.i2c > /sys/bus/platform/drivers/imx-i2c/unbind Unable to handle kernel NULL pointer dereference at virtual address 00000000 Internal error: Oops: 17 [#1] SMP ARM CPU: 2 PID: 533 Comm: sh Not tainted 4.9.0-rc3+ #61 Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) task: e5ada400 task.stack: e4936000 PC is at i2c_do_del_adapter+0x20/0xcc LR is at __process_removed_adapter+0x14/0x1c Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: 35bd004a DAC: 00000051 Process sh (pid: 533, stack limit = 0xe4936210) Stack: (0xe4937d28 to 0xe4938000) Backtrace: [<c0667be0>] (i2c_do_del_adapter) from [<c0667cc0>] (__process_removed_adapter+0x14/0x1c) [<c0667cac>] (__process_removed_adapter) from [<c0516998>] (bus_for_each_drv+0x6c/0xa0) [<c051692c>] (bus_for_each_drv) from [<c06685ec>] (i2c_del_adapter+0xbc/0x284) [<c0668530>] (i2c_del_adapter) from [<bf0110ec>] (i2c_imx_remove+0x44/0x164 [i2c_imx]) [<bf0110a8>] (i2c_imx_remove [i2c_imx]) from [<c051a838>] (platform_drv_remove+0x2c/0x44) [<c051a80c>] (platform_drv_remove) from [<c05183d8>] (__device_release_driver+0x90/0x12c) [<c0518348>] (__device_release_driver) from [<c051849c>] (device_release_driver+0x28/0x34) [<c0518474>] (device_release_driver) from [<c0517150>] (unbind_store+0x80/0x104) [<c05170d0>] (unbind_store) from [<c0516520>] (drv_attr_store+0x28/0x34) [<c05164f8>] (drv_attr_store) from [<c0298acc>] (sysfs_kf_write+0x50/0x54) [<c0298a7c>] (sysfs_kf_write) from [<c029801c>] (kernfs_fop_write+0x100/0x214) [<c0297f1c>] (kernfs_fop_write) from [<c0220130>] (__vfs_write+0x34/0x120) [<c02200fc>] (__vfs_write) from [<c0221088>] (vfs_write+0xa8/0x170) [<c0220fe0>] (vfs_write) from [<c0221e74>] (SyS_write+0x4c/0xa8) [<c0221e28>] (SyS_write) from [<c0108a20>] (ret_fast_syscall+0x0/0x1c) Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2016-10-25i2c: imx: defer probe if bus recovery GPIOs are not readyStefan Agner
Some SoC might load the GPIO driver after the I2C driver and using the I2C bus recovery mechanism via GPIOs. In this case it is crucial to defer probing if the GPIO request functions do so, otherwise the I2C driver gets loaded without recovery mechanisms enabled. Signed-off-by: Stefan Agner <stefan@agner.ch> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Li Yang <leoyang.li@nxp.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2016-10-25i2c: designware: Avoid aborted transfers with fast reacting I2C slavesJarkko Nikula
I2C DesignWare may abort transfer with arbitration lost if I2C slave pulls SDA down quickly after falling edge of SCL. Reason for this is unknown but after trial and error it was found this can be avoided by enabling non-zero SDA RX hold time for the receiver. By the specification SDA RX hold time extends incoming SDA low to high transition by n * ic_clk cycles but only when SCL is high. However it seems to help avoid above faulty arbitration lost error. Bits 23:16 in IC_SDA_HOLD register define the SDA RX hold time for the receiver. Be conservative and enable 1 ic_clk cycle long hold time in case boot firmware hasn't set it up. Reported-by: Jukka Laitinen <jukka.laitinen@intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Jukka Laitinen <jukka.laitinen@intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25i2c: i801: Fix I2C Block Read on 8-Series/C220 and laterJean Delvare
Starting with the 8-Series/C220 PCH (Lynx Point), the SMBus controller includes a SPD EEPROM protection mechanism. Once the SPD Write Disable bit is set, only reads are allowed to slave addresses 0x50-0x57. However the legacy implementation of I2C Block Read since the ICH5 looks like a write, and is therefore blocked by the SPD protection mechanism. This causes the eeprom and at24 drivers to fail. So assume that I2C Block Read is implemented as an actual read on these chipsets. I tested it on my Q87 chipset and it seems to work just fine. Signed-off-by: Jean Delvare <jdelvare@suse.de> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> [wsa: rebased to v4.9-rc2] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25i2c: xgene: Avoid dma_buffer overrunHoan Tran
SMBus block command uses the first byte of buffer for the data length. The dma_buffer should be increased by 1 to avoid the overrun issue. Reported-by: Phil Endecott <phil_gjouf_endecott@chezphil.org> Signed-off-by: Hoan Tran <hotran@apm.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2016-10-25i2c: digicolor: Fix module autoloadJavier Martinez Canillas
If the driver is built as a module, autoload won't work because the module alias information is not filled. So user-space can't match the registered device with the corresponding module. Export the module alias information using the MODULE_DEVICE_TABLE() macro. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25i2c: xlr: Fix module autoload for OF registrationJavier Martinez Canillas
If the driver is built as a module, autoload won't work because the module alias information is not filled. So user-space can't match the registered device with the corresponding module. Export the module alias information using the MODULE_DEVICE_TABLE() macro. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25i2c: xlp9xx: Fix module autoloadJavier Martinez Canillas
If the driver is built as a module, autoload won't work because the module alias information is not filled. So user-space can't match the registered device with the corresponding module. Export the module alias information using the MODULE_DEVICE_TABLE() macro. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25i2c: jz4780: Fix module autoloadJavier Martinez Canillas
If the driver is built as a module, autoload won't work because the module alias information is not filled. So user-space can't match the registered device with the corresponding module. Export the module alias information using the MODULE_DEVICE_TABLE() macro. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25i2c: allow configuration of imx driver for ColdFire architectureGreg Ungerer
The i2c controller used by Freescales iMX processors is the same hardware module used on Freescales ColdFire family of processors. We can use the existing i2c-imx driver on ColdFire family members. Modify the configuration to allow it to be selected when compiling for ColdFire targets. Signed-off-by: Greg Ungerer <gerg@linux-m68k.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-25i2c: mark device nodes only in case of successful instantiationRalf Ramsauer
Instantiated I2C device nodes are marked with OF_POPULATE. This was introduced in 4f001fd30145a6. On unloading, loaded device nodes will of course be unmarked. The problem are nodes that fail during initialisation: If a node fails, it won't be unloaded and hence not be unmarked. If a I2C driver module is unloaded and reloaded, it will skip nodes that failed before. Skip device nodes that are already populated and mark them only in case of success. Fixes: 4f001fd30145a6 ("i2c: Mark instantiated device nodes with OF_POPULATE") Signed-off-by: Ralf Ramsauer <ralf@ramses-pyramidenbau.de> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com> [wsa: use 14-digit commit sha] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2016-10-25i2c: rk3x: Give the tuning value 0 during rk3x_i2c_v0_calc_timingsDavid Wu
We found a bug that i2c transfer sometimes failed on 3066a board with stabel-4.8, the con register would be updated by uninitialized tuning value, it made the i2c transfer failed. So give the tuning value to be zero during rk3x_i2c_v0_calc_timings. Signed-off-by: David Wu <david.wu@rock-chips.com> Tested-by: Andy Yan <andy.yan@rock-chips.com> Reviewed-by: Douglas Anderson <dianders@chromium.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2016-10-25i2c: hix5hd2: allow build with ARCH_HISIRuqiang Ju
This driver should be buildable with ARCH_HISI, because some of other HiSilicon SoCs also use it. Signed-off-by: Ruqiang Ju <juruqiang@huawei.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-11Merge tag 'tegra-for-4.8-i2c' of ↵Wolfram Sang
git://git.kernel.org/pub/scm/linux/kernel/git/tegra/linux into i2c/for-next [wsa: fell through the cracks, applied to 4.9 now] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> i2c: 'i2c-bus' node support for v4.8-rc1 This includes the device tree binding and I2C core changes to support the i2c-bus subnode that I2C masters can use to describe their slaves in a separate namespace and therefore avoid clashing with potentially other subnodes.
2016-10-07Merge branch 'i2c/for-4.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "Here is the 4.9 pull request from I2C including: - centralized error messages when registering to the core - improved lockdep annotations to prevent false positives - DT support for muxes, gates, and arbitrators - bus speeds can now be obtained from ACPI - i2c-octeon got refactored and now supports ThunderX SoCs, too - i2c-tegra and i2c-designware got a bigger bunch of updates - a couple of standard driver fixes and improvements" * 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits) i2c: axxia: disable clks in case of failure in probe i2c: octeon: thunderx: Limit register access retries i2c: uniphier-f: fix misdetection of incomplete STOP condition gpio: pca953x: variable 'id' was used twice i2c: i801: Add support for Kaby Lake PCH-H gpio: pca953x: fix an incorrect lockdep warning i2c: add a warning to i2c_adapter_depth() lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible i2c: export i2c_adapter_depth() i2c: rk3x: Fix variable 'min_total_ns' unused warning i2c: rk3x: Fix sparse warning i2c / ACPI: Do not touch an I2C device if it belongs to another adapter i2c: octeon: Fix high-level controller status check i2c: octeon: Avoid sending STOP during recovery i2c: octeon: Fix set SCL recovery function i2c: rcar: add support for r8a7796 (R-Car M3-W) i2c: imx: make bus recovery through pinctrl optional i2c: meson: add gxbb compatible string i2c: uniphier-f: set the adapter to master mode when probing i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path ...
2016-10-02Merge branches 'acpi-wdat' and 'acpi-ec'Rafael J. Wysocki
* acpi-wdat: watchdog: wdat_wdt: Fix warning for using 0 as NULL watchdog: wdat_wdt: fix return value check in wdat_wdt_probe() platform/x86: intel_pmc_ipc: Do not create iTCO watchdog when WDAT table exists i2c: i801: Do not create iTCO watchdog when WDAT table exists mfd: lpc_ich: Do not create iTCO watchdog when WDAT table exists ACPI / watchdog: Add support for WDAT hardware watchdog * acpi-ec: ACPI / EC: Fix issues related to boot_ec ACPI / EC: Fix a gap that ECDT EC cannot handle EC events ACPI / EC: Fix a memory leakage issue in acpi_ec_add() ACPI / EC: Cleanup first_ec/boot_ec code ACPI / EC: Enable event freeze mode to improve event handling for suspend process ACPI / EC: Add PM operations to improve event handling for suspend process ACPI / EC: Add PM operations to improve event handling for resume process ACPI / EC: Fix an issue that SCI_EVT cannot be detected after event is enabled ACPI / EC: Add EC_FLAGS_QUERY_ENABLED to reveal a hidden logic ACPI / EC: Add PM operations for suspend/resume noirq stage