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2020-08-21i2c: iproc: fix race between client unreg and isrDhananjay Phadke
[ Upstream commit b1eef236f50ba6afea680da039ef3a2ca9c43d11 ] When i2c client unregisters, synchronize irq before setting iproc_i2c->slave to NULL. (1) disable_irq() (2) Mask event enable bits in control reg (3) Erase slave address (avoid further writes to rx fifo) (4) Flush tx and rx FIFOs (5) Clear pending event (interrupt) bits in status reg (6) enable_irq() (7) Set client pointer to NULL Unable to handle kernel NULL pointer dereference at virtual address 0000000000000318 [ 371.020421] pc : bcm_iproc_i2c_isr+0x530/0x11f0 [ 371.025098] lr : __handle_irq_event_percpu+0x6c/0x170 [ 371.030309] sp : ffff800010003e40 [ 371.033727] x29: ffff800010003e40 x28: 0000000000000060 [ 371.039206] x27: ffff800010ca9de0 x26: ffff800010f895df [ 371.044686] x25: ffff800010f18888 x24: ffff0008f7ff3600 [ 371.050165] x23: 0000000000000003 x22: 0000000001600000 [ 371.055645] x21: ffff800010f18888 x20: 0000000001600000 [ 371.061124] x19: ffff0008f726f080 x18: 0000000000000000 [ 371.066603] x17: 0000000000000000 x16: 0000000000000000 [ 371.072082] x15: 0000000000000000 x14: 0000000000000000 [ 371.077561] x13: 0000000000000000 x12: 0000000000000001 [ 371.083040] x11: 0000000000000000 x10: 0000000000000040 [ 371.088519] x9 : ffff800010f317c8 x8 : ffff800010f317c0 [ 371.093999] x7 : ffff0008f805b3b0 x6 : 0000000000000000 [ 371.099478] x5 : ffff0008f7ff36a4 x4 : ffff8008ee43d000 [ 371.104957] x3 : 0000000000000000 x2 : ffff8000107d64c0 [ 371.110436] x1 : 00000000c00000af x0 : 0000000000000000 [ 371.115916] Call trace: [ 371.118439] bcm_iproc_i2c_isr+0x530/0x11f0 [ 371.122754] __handle_irq_event_percpu+0x6c/0x170 [ 371.127606] handle_irq_event_percpu+0x34/0x88 [ 371.132189] handle_irq_event+0x40/0x120 [ 371.136234] handle_fasteoi_irq+0xcc/0x1a0 [ 371.140459] generic_handle_irq+0x24/0x38 [ 371.144594] __handle_domain_irq+0x60/0xb8 [ 371.148820] gic_handle_irq+0xc0/0x158 [ 371.152687] el1_irq+0xb8/0x140 [ 371.155927] arch_cpu_idle+0x10/0x18 [ 371.159615] do_idle+0x204/0x290 [ 371.162943] cpu_startup_entry+0x24/0x60 [ 371.166990] rest_init+0xb0/0xbc [ 371.170322] arch_call_rest_init+0xc/0x14 [ 371.174458] start_kernel+0x404/0x430 Fixes: c245d94ed106 ("i2c: iproc: Add multi byte read-write support for slave mode") Signed-off-by: Dhananjay Phadke <dphadke@linux.microsoft.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Ray Jui <ray.jui@broadcom.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21i2c: rcar: avoid race when unregistering slaveWolfram Sang
[ Upstream commit c7c9e914f9a0478fba4dc6f227cfd69cf84a4063 ] Due to the lockless design of the driver, it is theoretically possible to access a NULL pointer, if a slave interrupt was running while we were unregistering the slave. To make this rock solid, disable the interrupt for a short time while we are clearing the interrupt_enable register. This patch is purely based on code inspection. The OOPS is super-hard to trigger because clearing SAR (the address) makes interrupts even more unlikely to happen as well. While here, reinit SCR to SDBS because this bit should always be set according to documentation. There is no effect, though, because the interface is disabled. Fixes: 7b814d852af6 ("i2c: rcar: avoid race when unregistering slave client") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21i2c: rcar: slave: only send STOP event when we have been addressedWolfram Sang
[ Upstream commit 314139f9f0abdba61ed9a8463bbcb0bf900ac5a2 ] When the SSR interrupt is activated, it will detect every STOP condition on the bus, not only the ones after we have been addressed. So, enable this interrupt only after we have been addressed, and disable it otherwise. Fixes: de20d1857dd6 ("i2c: rcar: add slave support") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-11i2c: slave: add sanity check when unregisteringWolfram Sang
[ Upstream commit 8808981baf96e1b3dea1f08461e4d958aa0dbde1 ] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Alain Volmat <alain.volmat@st.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-11i2c: slave: improve sanity check when registeringWolfram Sang
[ Upstream commit 1b1be3bf27b62f5abcf85c6f3214bdb9c7526685 ] Add check for ERR_PTR and simplify code while here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Alain Volmat <alain.volmat@st.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-05Revert "i2c: cadence: Fix the hold bit setting"Raviteja Narayanam
[ Upstream commit 0db9254d6b896b587759e2c844c277fb1a6da5b9 ] This reverts commit d358def706880defa4c9e87381c5bf086a97d5f9. There are two issues with "i2c: cadence: Fix the hold bit setting" commit. 1. In case of combined message request from user space, when the HOLD bit is cleared in cdns_i2c_mrecv function, a STOP condition is sent on the bus even before the last message is started. This is because when the HOLD bit is cleared, the FIFOS are empty and there is no pending transfer. The STOP condition should occur only after the last message is completed. 2. The code added by the commit is redundant. Driver is handling the setting/clearing of HOLD bit in right way before the commit. The setting of HOLD bit based on 'bus_hold_flag' is taken care in cdns_i2c_master_xfer function even before cdns_i2c_msend/cdns_i2c_recv functions. The clearing of HOLD bit is taken care at the end of cdns_i2c_msend and cdns_i2c_recv functions based on bus_hold_flag and byte count. Since clearing of HOLD bit is done after the slave address is written to the register (writing to address register triggers the message transfer), it is ensured that STOP condition occurs at the right time after completion of the pending transfer (last message). Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-29i2c: i2c-qcom-geni: Fix DMA transfer raceDouglas Anderson
[ Upstream commit 02b9aec59243c6240fc42884acc958602146ddf6 ] When I have KASAN enabled on my kernel and I start stressing the touchscreen my system tends to hang. The touchscreen is one of the only things that does a lot of big i2c transfers and ends up hitting the DMA paths in the geni i2c driver. It appears that KASAN adds enough delay in my system to tickle a race condition in the DMA setup code. When the system hangs, I found that it was running the geni_i2c_irq() over and over again. It had these: m_stat = 0x04000080 rx_st = 0x30000011 dm_tx_st = 0x00000000 dm_rx_st = 0x00000000 dma = 0x00000001 Notably we're in DMA mode but are getting M_RX_IRQ_EN and M_RX_FIFO_WATERMARK_EN over and over again. Putting some traces in geni_i2c_rx_one_msg() showed that when we failed we were getting to the start of geni_i2c_rx_one_msg() but were never executing geni_se_rx_dma_prep(). I believe that the problem here is that we are starting the geni command before we run geni_se_rx_dma_prep(). If a transfer makes it far enough before we do that then we get into the state I have observed. Let's change the order, which seems to work fine. Although problems were seen on the RX path, code inspection suggests that the TX should be changed too. Change it as well. Fixes: 37692de5d523 ("i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller") Signed-off-by: Douglas Anderson <dianders@chromium.org> Tested-by: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org> Reviewed-by: Akash Asthana <akashast@codeaurora.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Mukesh Kumar Savaliya <msavaliy@codeaurora.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-29i2c: rcar: always clear ICSAR to avoid side effectsWolfram Sang
[ Upstream commit eb01597158ffb1853a7a7fc2c57d4c844640f75e ] On R-Car Gen2, we get a timeout when reading from the address set in ICSAR, even though the slave interface is disabled. Clearing it fixes this situation. Note that Gen3 is not affected. To reproduce: bind and undbind an I2C slave on some bus, run 'i2cdetect' on that bus. Fixes: de20d1857dd6 ("i2c: rcar: add slave support") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-22i2c: eg20t: Load module automatically if ID matchesAndy Shevchenko
[ Upstream commit 5f90786b31fb7d1e199a8999d46c4e3aea672e11 ] The driver can't be loaded automatically because it misses module alias to be provided. Add corresponding MODULE_DEVICE_TABLE() call to the driver. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-09i2c: mlxcpld: check correct size of maximum RECV_LEN packetWolfram Sang
[ Upstream commit 597911287fcd13c3a4b4aa3e0a52b33d431e0a8e ] I2C_SMBUS_BLOCK_MAX defines already the maximum number as defined in the SMBus 2.0 specs. I don't see a reason to add 1 here. Also, fix the errno to what is suggested for this error. Fixes: c9bfdc7c16cb ("i2c: mlxcpld: Add support for smbus block read transaction") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Michael Shych <michaelsh@mellanox.com> Tested-by: Michael Shych <michaelsh@mellanox.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-09i2c: algo-pca: Add 0x78 as SCL stuck low status for PCA9665Chris Packham
[ Upstream commit cd217f2300793a106b49c7dfcbfb26e348bc7593 ] The PCA9665 datasheet says that I2CSTA = 78h indicates that SCL is stuck low, this differs to the PCA9564 which uses 90h for this indication. Treat either 0x78 or 0x90 as an indication that the SCL line is stuck. Based on looking through the PCA9564 and PCA9665 datasheets this should be safe for both chips. The PCA9564 should not return 0x78 for any valid state and the PCA9665 should not return 0x90. Fixes: eff9ec95efaa ("i2c-algo-pca: Add PCA9665 support") Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30i2c: core: check returned size of emulated smbus block readMans Rullgard
[ Upstream commit 40e05200593af06633f64ab0effff052eee6f076 ] If the i2c bus driver ignores the I2C_M_RECV_LEN flag (as some of them do), it is possible for an I2C_SMBUS_BLOCK_DATA read issued on some random device to return an arbitrary value in the first byte (and nothing else). When this happens, i2c_smbus_xfer_emulated() will happily write past the end of the supplied data buffer, thus causing Bad Things to happen. To prevent this, check the size before copying the data block and return an error if it is too large. Fixes: 209d27c3b167 ("i2c: Emulate SMBus block read over I2C") Signed-off-by: Mans Rullgard <mans@mansr.com> [wsa: use better errno] Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30i2c: fsi: Fix the port number field in status registerEddie James
[ Upstream commit 502035e284cc7e9efef22b01771d822d49698ab9 ] The port number field in the status register was not correct, so fix it. Fixes: d6ffb6300116 ("i2c: Add FSI-attached I2C master algorithm") Signed-off-by: Eddie James <eajames@linux.ibm.com> Signed-off-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-30Revert "i2c: tegra: Fix suspending in active runtime PM state"Thierry Reding
[ Upstream commit 78ad73421831247e46c31899a7bead02740e4bef ] This reverts commit 9f42de8d4ec2304f10bbc51dc0484f3503d61196. It's not safe to use pm_runtime_force_{suspend,resume}(), especially during the noirq phase of suspend. See also the guidance provided in commit 1e2ef05bb8cf ("PM: Limit race conditions between runtime PM and system sleep (v2)"). Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24i2c: icy: Fix build with CONFIG_AMIGA_PCMCIA=nMax Staudt
[ Upstream commit cdb555397f438592bab00599037c347b700cf397 ] This has been found by the Kernel Test Robot: http://lkml.iu.edu/hypermail/linux/kernel/2006.0/06862.html With CONFIG_AMIGA_PCMCIA=n, io_mm.h does not pull in amigahw.h and ZTWO_VADDR is undefined. Add forgotten include to i2c-icy.c Fixes: 4768e90ecaec ("i2c: Add i2c-icy for I2C on m68k/Amiga") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Max Staudt <max@enpas.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24i2c: pxa: fix i2c_pxa_scream_blue_murder() debug outputRussell King
[ Upstream commit 88b73ee7ca4c90baf136ed5a8377fc5a9b73ac08 ] The IRQ log output is supposed to appear on a single line. However, commit 3a2dc1677b60 ("i2c: pxa: Update debug function to dump more info on error") resulted in it being printed one-entry-per-line, which is excessively long. Fixing this is not a trivial matter; using pr_cont() doesn't work as the previous dev_dbg() may not have been compiled in, or may be dynamic. Since the rest of this function output is at error level, and is also debug output, promote this to error level as well to avoid this problem. Reduce the number of always zero prefix digits to save screen real- estate. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24i2c: pxa: clear all master action bits in i2c_pxa_stop_message()Russell King
[ Upstream commit e81c979f4e071d516aa27cf5a0c3939da00dc1ca ] If we timeout during a message transfer, the control register may contain bits that cause an action to be set. Read-modify-writing the register leaving these bits set may trigger the hardware to attempt one of these actions unintentionally. Always clear these bits when cleaning up after a message or after a timeout. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24i2c: piix4: Detect secondary SMBus controller on AMD AM4 chipsetsAdam Honse
[ Upstream commit f27237c174fd9653033330e4e532cd9d153ce824 ] The AMD X370 and other AM4 chipsets (A/B/X 3/4/5 parts) and Threadripper equivalents have a secondary SMBus controller at I/O port address 0x0B20. This bus is used by several manufacturers to control motherboard RGB lighting via embedded controllers. I have been using this bus in my OpenRGB project to control the Aura RGB on many motherboards and ASRock also uses this bus for their Polychrome RGB controller. I am not aware of any CZ-compatible platforms which do not have the second SMBus channel. All of AMD's AM4- and Threadripper- series chipsets that OpenRGB users have tested appear to have this secondary bus. I also noticed this secondary bus is present on older AMD platforms including my FM1 home server. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202587 Signed-off-by: Adam Honse <calcprogrammer1@gmail.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com> Tested-by: Sebastian Reichel <sebastian.reichel@collabora.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-07i2c: altera: Fix race between xfer_msg and isr threadAtsushi Nemoto
[ Upstream commit 5d4c7977499a736f3f80826bdc9744344ad55589 ] Use a mutex to protect access to idev->msg_len, idev->buf, etc. which are modified by both altr_i2c_xfer_msg() and altr_i2c_isr(). This is the minimal fix for easy backporting. A cleanup to remove the spinlock will be added later. Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp> Acked-by: Thor Thayer <thor.thayer@linux.intel.com> [wsa: updated commit message] Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27i2c: mux: demux-pinctrl: Fix an error handling path in ↵Christophe JAILLET
'i2c_demux_pinctrl_probe()' [ Upstream commit e9d1a0a41d4486955e96552293c1fcf1fce61602 ] A call to 'i2c_demux_deactivate_master()' is missing in the error handling path, as already done in the remove function. Fixes: 50a5ba876908 ("i2c: mux: demux-pinctrl: add driver") Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27i2c: fix missing pm_runtime_put_sync in i2c_device_probeAlain Volmat
[ Upstream commit 3c3dd56f760da056e821ac177e3ad0de4209a435 ] In case of the I2C client exposes the flag I2C_CLIENT_HOST_NOTIFY, pm_runtime_get_sync is called in order to always keep active the adapter. However later on, pm_runtime_put_sync is never called within the function in case of an error. This commit add this error handling. Fixes: 72bfcee11cf8 ("i2c: Prevent runtime suspend of adapter when Host Notify is required") Signed-off-by: Alain Volmat <alain.volmat@st.com> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-05-27i2c: dev: Fix the race between the release of i2c_dev and cdevKevin Hao
commit 1413ef638abae4ab5621901cf4d8ef08a4a48ba6 upstream. The struct cdev is embedded in the struct i2c_dev. In the current code, we would free the i2c_dev struct directly in put_i2c_dev(), but the cdev is manged by a kobject, and the release of it is not predictable. So it is very possible that the i2c_dev is freed before the cdev is entirely released. We can easily get the following call trace with CONFIG_DEBUG_KOBJECT_RELEASE and CONFIG_DEBUG_OBJECTS_TIMERS enabled. ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x38 WARNING: CPU: 19 PID: 1 at lib/debugobjects.c:325 debug_print_object+0xb0/0xf0 Modules linked in: CPU: 19 PID: 1 Comm: swapper/0 Tainted: G W 5.2.20-yocto-standard+ #120 Hardware name: Marvell OcteonTX CN96XX board (DT) pstate: 80c00089 (Nzcv daIf +PAN +UAO) pc : debug_print_object+0xb0/0xf0 lr : debug_print_object+0xb0/0xf0 sp : ffff00001292f7d0 x29: ffff00001292f7d0 x28: ffff800b82151788 x27: 0000000000000001 x26: ffff800b892c0000 x25: ffff0000124a2558 x24: 0000000000000000 x23: ffff00001107a1d8 x22: ffff0000116b5088 x21: ffff800bdc6afca8 x20: ffff000012471ae8 x19: ffff00001168f2c8 x18: 0000000000000010 x17: 00000000fd6f304b x16: 00000000ee79de43 x15: ffff800bc0e80568 x14: 79616c6564203a74 x13: 6e6968207473696c x12: 5f72656d6974203a x11: ffff0000113f0018 x10: 0000000000000000 x9 : 000000000000001f x8 : 0000000000000000 x7 : ffff0000101294cc x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000001 x3 : 00000000ffffffff x2 : 0000000000000000 x1 : 387fc15c8ec0f200 x0 : 0000000000000000 Call trace: debug_print_object+0xb0/0xf0 __debug_check_no_obj_freed+0x19c/0x228 debug_check_no_obj_freed+0x1c/0x28 kfree+0x250/0x440 put_i2c_dev+0x68/0x78 i2cdev_detach_adapter+0x60/0xc8 i2cdev_notifier_call+0x3c/0x70 notifier_call_chain+0x8c/0xe8 blocking_notifier_call_chain+0x64/0x88 device_del+0x74/0x380 device_unregister+0x54/0x78 i2c_del_adapter+0x278/0x2d0 unittest_i2c_bus_remove+0x3c/0x80 platform_drv_remove+0x30/0x50 device_release_driver_internal+0xf4/0x1c0 driver_detach+0x58/0xa0 bus_remove_driver+0x84/0xd8 driver_unregister+0x34/0x60 platform_driver_unregister+0x20/0x30 of_unittest_overlay+0x8d4/0xbe0 of_unittest+0xae8/0xb3c do_one_initcall+0xac/0x450 do_initcall_level+0x208/0x224 kernel_init_freeable+0x2d8/0x36c kernel_init+0x18/0x108 ret_from_fork+0x10/0x1c irq event stamp: 3934661 hardirqs last enabled at (3934661): [<ffff00001009fa04>] debug_exception_exit+0x4c/0x58 hardirqs last disabled at (3934660): [<ffff00001009fb14>] debug_exception_enter+0xa4/0xe0 softirqs last enabled at (3934654): [<ffff000010081d94>] __do_softirq+0x46c/0x628 softirqs last disabled at (3934649): [<ffff0000100b4a1c>] irq_exit+0x104/0x118 This is a common issue when using cdev embedded in a struct. Fortunately, we already have a mechanism to solve this kind of issue. Please see commit 233ed09d7fda ("chardev: add helper function to register char devs with a struct device") for more detail. In this patch, we choose to embed the struct device into the i2c_dev, and use the API provided by the commit 233ed09d7fda to make sure that the release of i2c_dev and cdev are in sequence. Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: Ben Hutchings <ben.hutchings@codethink.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-06i2c: aspeed: Avoid i2c interrupt status clear race condition.ryan_chen
commit c926c87b8e36dcc0ea5c2a0a0227ed4f32d0516a upstream. In AST2600 there have a slow peripheral bus between CPU and i2c controller. Therefore GIC i2c interrupt status clear have delay timing, when CPU issue write clear i2c controller interrupt status. To avoid this issue, the driver need have read after write clear at i2c ISR. Fixes: f327c686d3ba ("i2c: aspeed: added driver for Aspeed I2C") Signed-off-by: ryan_chen <ryan_chen@aspeedtech.com> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [wsa: added Fixes tag] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-06i2c: iproc: generate stop event for slave writesRayagonda Kokatanur
commit 068143a8195fb0fdeea1f3ca430b3db0f6d04a53 upstream. When slave status is I2C_SLAVE_RX_END, generate I2C_SLAVE_STOP event to i2c_client. Fixes: c245d94ed106 ("i2c: iproc: Add multi byte read-write support for slave mode") Signed-off-by: Rayagonda Kokatanur <rayagonda.kokatanur@broadcom.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-06i2c: amd-mp2-pci: Fix Oops in amd_mp2_pci_init() error handlingDan Carpenter
commit ac2b0813fceaf7cb3d8d46c7b33c90bae9fa49db upstream. The problem is that we dereference "privdata->pci_dev" when we print the error messages in amd_mp2_pci_init(): dev_err(ndev_dev(privdata), "Failed to enable MP2 PCI device\n"); ^^^^^^^^^^^^^^^^^ Fixes: 529766e0a011 ("i2c: Add drivers for the AMD PCIe MP2 I2C controller") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-05-02i2c: altera: use proper variable to hold errnoWolfram Sang
commit edb2c9dd3948738ef030c32b948543e84f4d3f81 upstream. device_property_read_u32() returns errno or 0, so we should use the integer variable 'ret' and not the u32 'val' to hold the retval. Fixes: 0560ad576268 ("i2c: altera: Add Altera I2C Controller driver") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-21i2c: designware: platdrv: Remove DPM_FLAG_SMART_SUSPEND flag on BYT and CHTHans de Goede
commit d79294d0de12ddd1420110813626d691f440b86f upstream. We already set DPM_FLAG_SMART_PREPARE, so we completely skip all callbacks (other then prepare) where possible, quoting from dw_i2c_plat_prepare(): /* * If the ACPI companion device object is present for this device, it * may be accessed during suspend and resume of other devices via I2C * operation regions, so tell the PM core and middle layers to avoid * skipping system suspend/resume callbacks for it in that case. */ return !has_acpi_companion(dev); Also setting the DPM_FLAG_SMART_SUSPEND will cause acpi_subsys_suspend() to leave the controller runtime-suspended even if dw_i2c_plat_prepare() returned 0. Leaving the controller runtime-suspended normally, when the I2C controller is suspended during the suspend_late phase, is not an issue because the pm_runtime_get_sync() done by i2c_dw_xfer() will (runtime-)resume it. But for dw I2C controllers on Bay- and Cherry-Trail devices acpi_lpss.c leaves the controller alive until the suspend_noirq phase, because it may be used by the _PS3 ACPI methods of PCI devices and PCI devices are left powered on until the suspend_noirq phase. Between the suspend_late and resume_early phases runtime-pm is disabled. So for any ACPI I2C OPRegion accesses done after the suspend_late phase, the pm_runtime_get_sync() done by i2c_dw_xfer() is a no-op and the controller is left runtime-suspended. i2c_dw_xfer() has a check to catch this condition (rather then waiting for the I2C transfer to timeout because the controller is suspended). acpi_subsys_suspend() leaving the controller runtime-suspended in combination with an ACPI I2C OPRegion access done after the suspend_late phase triggers this check, leading to the following error being logged on a Bay Trail based Lenovo Thinkpad 8 tablet: [ 93.275882] i2c_designware 80860F41:00: Transfer while suspended [ 93.275993] WARNING: CPU: 0 PID: 412 at drivers/i2c/busses/i2c-designware-master.c:429 i2c_dw_xfer+0x239/0x280 ... [ 93.276252] Workqueue: kacpi_notify acpi_os_execute_deferred [ 93.276267] RIP: 0010:i2c_dw_xfer+0x239/0x280 ... [ 93.276340] Call Trace: [ 93.276366] __i2c_transfer+0x121/0x520 [ 93.276379] i2c_transfer+0x4c/0x100 [ 93.276392] i2c_acpi_space_handler+0x219/0x510 [ 93.276408] ? up+0x40/0x60 [ 93.276419] ? i2c_acpi_notify+0x130/0x130 [ 93.276433] acpi_ev_address_space_dispatch+0x1e1/0x252 ... So since on BYT and CHT platforms we want ACPI I2c OPRegion accesses to work until the suspend_noirq phase, we need the controller to be runtime-resumed during the suspend phase if it is runtime-suspended suspended at that time. This means that we must not set the DPM_FLAG_SMART_SUSPEND on these platforms. On BYT and CHT we already have a special ACCESS_NO_IRQ_SUSPEND flag to make sure the controller stays functional until the suspend_noirq phase. This commit makes the driver not set the DPM_FLAG_SMART_SUSPEND flag when that flag is set. Cc: stable@vger.kernel.org Fixes: b30f2f65568f ("i2c: designware: Set IRQF_NO_SUSPEND flag for all BYT and CHT controllers") Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-17i2c: pca-platform: Use platform_irq_get_optionalChris Packham
[ Upstream commit 14c1fe699cad9cb0acda4559c584f136d18fea50 ] The interrupt is not required so use platform_irq_get_optional() to avoid error messages like i2c-pca-platform 22080000.i2c: IRQ index 0 not found Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-17i2c: st: fix missing struct parameter descriptionAlain Volmat
[ Upstream commit f491c6687332920e296d0209e366fe2ca7eab1c6 ] Fix a missing struct parameter description to allow warning free W=1 compilation. Signed-off-by: Alain Volmat <avolmat@me.com> Reviewed-by: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-08i2c: i801: Do not add ICH_RES_IO_SMI for the iTCO_wdt deviceMika Westerberg
commit 04bbb97d1b732b2d197f103c5818f5c214a4cf81 upstream. Martin noticed that nct6775 driver does not load properly on his system in v5.4+ kernels. The issue was bisected to commit b84398d6d7f9 ("i2c: i801: Use iTCO version 6 in Cannon Lake PCH and beyond") but it is likely not the culprit because the faulty code has been in the driver already since commit 9424693035a5 ("i2c: i801: Create iTCO device on newer Intel PCHs"). So more likely some commit that added PCI IDs of recent chipsets made the driver to create the iTCO_wdt device on Martins system. The issue was debugged to be PCI configuration access to the PMC device that is not present. This returns all 1's when read and this caused the iTCO_wdt driver to accidentally request resourses used by nct6775. It turns out that the SMI resource is only required for some ancient systems, not the ones supported by this driver. For this reason do not populate the SMI resource at all and drop all the related code. The driver now always populates the main I/O resource and only in case of SPT (Intel Sunrisepoint) compatible devices it adds another resource for the NO_REBOOT bit. These two resources are of different types so platform_get_resource() used by the iTCO_wdt driver continues to find the both resources at index 0. Link: https://lore.kernel.org/linux-hwmon/CAM1AHpQ4196tyD=HhBu-2donSsuogabkfP03v1YF26Q7_BgvgA@mail.gmail.com/ Fixes: 9424693035a5 ("i2c: i801: Create iTCO device on newer Intel PCHs") [wsa: complete fix needs all of http://patchwork.ozlabs.org/project/linux-i2c/list/?series=160959&state=*] Reported-by: Martin Volf <martin.volf.42@gmail.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-01i2c: nvidia-gpu: Handle timeout correctly in gpu_i2c_check_status()Kai-Heng Feng
commit d944b27df121e2ee854a6c2fad13d6c6300792d4 upstream. Nvidia card may come with a "phantom" UCSI device, and its driver gets stuck in probe routine, prevents any system PM operations like suspend. There's an unaccounted case that the target time can equal to jiffies in gpu_i2c_check_status(), let's solve that by using readl_poll_timeout() instead of jiffies comparison functions. Fixes: c71bcdcb42a7 ("i2c: add i2c bus driver for NVIDIA GPU") Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Ajay Gupta <ajayg@nvidia.com> Tested-by: Ajay Gupta <ajayg@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-01i2c: hix5hd2: add missed clk_disable_unprepare in removeChuhong Yuan
commit e1b9f99ff8c40bba6e59de9ad4a659447b1e4112 upstream. The driver forgets to disable and unprepare clk when remove. Add a call to clk_disable_unprepare to fix it. Signed-off-by: Chuhong Yuan <hslester96@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18i2c: acpi: put device when verifying client failsWolfram Sang
commit 8daee952b4389729358665fb91949460641659d4 upstream. i2c_verify_client() can fail, so we need to put the device when that happens. Fixes: 525e6fabeae2 ("i2c / ACPI: add support for ACPI reconfigure notifications") Reported-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18i2c: gpio: suppress error on probe deferHamish Martin
commit 3747cd2efe7ecb9604972285ab3f60c96cb753a8 upstream. If a GPIO we are trying to use is not available and we are deferring the probe, don't output an error message. This seems to have been the intent of commit 05c74778858d ("i2c: gpio: Add support for named gpios in DT") but the error was still output due to not checking the updated 'retdesc'. Fixes: 05c74778858d ("i2c: gpio: Add support for named gpios in DT") Signed-off-by: Hamish Martin <hamish.martin@alliedtelesis.co.nz> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18i2c: designware-pci: Fix BUG_ON during device removalJarkko Nikula
commit 9be8bc4dd6177cf992b93b0bd014c4f611283896 upstream. Function i2c_dw_pci_remove() -> pci_free_irq_vectors() -> pci_disable_msi() -> free_msi_irqs() will throw a BUG_ON() for MSI enabled device since the driver has not released the requested IRQ before calling the pci_free_irq_vectors(). Here driver requests an IRQ using devm_request_irq() but automatic release happens only after remove callback. Fix this by explicitly freeing the IRQ before calling pci_free_irq_vectors(). Fixes: 21aa3983d619 ("i2c: designware-pci: Switch over to MSI interrupts") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-05i2c: jz4780: silence log flood on txabrtWolfram Sang
commit 9e661cedcc0a072d91a32cb88e0515ea26e35711 upstream. The printout for txabrt is way too talkative and is highly annoying with scanning programs like 'i2cdetect'. Reduce it to the minimum, the rest can be gained by I2C core debugging and datasheet information. Also, make it a debug printout, it won't help the regular user. Fixes: ba92222ed63a ("i2c: jz4780: Add i2c bus controller driver for Ingenic JZ4780") Reported-by: H. Nikolaus Schaller <hns@goldelico.com> Tested-by: H. Nikolaus Schaller <hns@goldelico.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-05i2c: altera: Fix potential integer overflowGustavo A. R. Silva
commit 54498e8070e19e74498a72c7331348143e7e1f8c upstream. Factor out 100 from the equation and do 32-bit arithmetic (3 * clk_mhz / 10) instead of 64-bit. Notice that clk_mhz is MHz, so the multiplication will never wrap 32 bits and there is no need for div_u64(). Addresses-Coverity: 1458369 ("Unintentional integer overflow") Fixes: 0560ad576268 ("i2c: altera: Add Altera I2C Controller driver") Suggested-by: David Laight <David.Laight@ACULAB.COM> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Reviewed-by: Thor Thayer <thor.thayer@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-26i2c: stm32f7: report dma error during probeAlain Volmat
[ Upstream commit d77eceb2de99f5d7e0c645bad15511fe1af59e09 ] Distinguish between the case where dma information is not provided within the DT and the case of an error during the dma init. Exit the probe with error in case of an error during dma init. Fixes: bb8822cbbc53 ("i2c: i2c-stm32: Add generic DMA API") Signed-off-by: Alain Volmat <alain.volmat@st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-26i2c: i2c-stm32f7: fix 10-bits check in slave free id search loopAlain Volmat
commit 7787657d7ee55a9ecf4aea4907b46b87a44eda67 upstream. Fix a typo in the free slave id search loop. Instead of I2C_CLIENT_PEC, it should have been I2C_CLIENT_TEN. The slave id 1 can only handle 7-bit addresses and thus is not eligible in case of 10-bit addresses. As a matter of fact none of the slave id support I2C_CLIENT_PEC, overall check is performed at the beginning of the stm32f7_i2c_reg_slave function. Fixes: 60d609f30de2 ("i2c: i2c-stm32f7: Add slave support") Signed-off-by: Alain Volmat <alain.volmat@st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-26i2c: stm32f7: rework slave_id allocationAlain Volmat
commit 52d3be711e065a97a57c2f2ffba3098748855bd6 upstream. The IP can handle two slave addresses. One address can either be 7 bits or 10 bits while the other can only be 7 bits. In order to ensure that a 10 bits address can always be allocated (assuming there is only one 7 bits address already allocated), pick up the 7-bits only address slot in priority when performing a 7-bits address allocation. Fixes: 60d609f30de2 ("i2c: i2c-stm32f7: Add slave support") Signed-off-by: Alain Volmat <alain.volmat@st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23i2c: iop3xx: Fix memory leak in probe error pathKrzysztof Kozlowski
commit e64175776d06a8ceebbfd349d7e66a4a46ca39ef upstream. When handling devm_gpiod_get_optional() errors, free the memory already allocated. This fixes Smatch warnings: drivers/i2c/busses/i2c-iop3xx.c:437 iop3xx_i2c_probe() warn: possible memory leak of 'new_adapter' drivers/i2c/busses/i2c-iop3xx.c:442 iop3xx_i2c_probe() warn: possible memory leak of 'new_adapter' Fixes: fdb7e884ad61 ("i2c: iop: Use GPIO descriptors") Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23i2c: tegra: Properly disable runtime PM on driver's probe errorDmitry Osipenko
commit 24a49678f5e20f18006e71b90ac1531876b27eb1 upstream. One of the recent Tegra I2C commits made a change that resumes runtime PM during driver's probe, but it missed to put the RPM in a case of error. Note that it's not correct to use pm_runtime_status_suspended because it breaks RPM refcounting. Fixes: 8ebf15e9c869 ("i2c: tegra: Move suspend handling to NOIRQ phase") Cc: <stable@vger.kernel.org> # v5.4+ Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-23i2c: tegra: Fix suspending in active runtime PM stateDmitry Osipenko
commit 9f42de8d4ec2304f10bbc51dc0484f3503d61196 upstream. I noticed that sometime I2C clock is kept enabled during suspend-resume. This happens because runtime PM defers dynamic suspension and thus it may happen that runtime PM is in active state when system enters into suspend. In particular I2C controller that is used for CPU's DVFS is often kept ON during suspend because CPU's voltage scaling happens quite often. Fixes: 8ebf15e9c869 ("i2c: tegra: Move suspend handling to NOIRQ phase") Cc: <stable@vger.kernel.org> # v5.4+ Tested-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-17i2c: bcm2835: Store pointer to bus clockStefan Wahren
commit 3b722da6672df8392f9c43d7c7e04bddd81d7e37 upstream. The commit bebff81fb8b9 ("i2c: bcm2835: Model Divider in CCF") introduced a NULL pointer dereference on driver unload. It seems that we can't fetch the bus clock via devm_clk_get in bcm2835_i2c_remove. As an alternative approach store a pointer to the bus clock in the private driver structure. Fixes: bebff81fb8b9 ("i2c: bcm2835: Model Divider in CCF") Signed-off-by: Stefan Wahren <wahrenst@gmx.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14i2c: fix bus recovery stop mode timingRussell King
commit cf8ce8b80f8bf9669f6ec4e71e16668430febdac upstream. The I2C specification states that tsu:sto for standard mode timing must be at minimum 4us. Pictographically, this is: SCL: ____/~~~~~~~~~ SDA: _________/~~~~ ->| |<- 4us minimum We are currently waiting 2.5us between asserting SCL and SDA, which is in violation of the standard. Adjust the timings to ensure that we meet what is stipulated as the minimum timings to ensure that all devices correctly interpret the STOP bus transition. This is more important than trying to generate a square wave with even duty cycle. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-04i2c: stm32f7: fix & reorder remove & probe error handlingAlain Volmat
[ Upstream commit 53aaaa5d9b1e95eb40e877fbffa6f964a8394bb7 ] Add missing dma channels free calls in case of error during probe and reorder the remove function so that dma channels are freed after the i2c adapter is deleted. Overall, reorder the remove function so that probe error handling order and remove function order are same. Fixes: 7ecc8cfde553 ("i2c: i2c-stm32f7: Add DMA support") Signed-off-by: Alain Volmat <alain.volmat@st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-15i2c: core: fix use after free in of_i2c_notifyWen Yang
We can't use "adap->dev" after it has been freed. Fixes: 5bf4fa7daea6 ("i2c: break out OF support into separate file") Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-11-15i2c: acpi: Force bus speed to 400KHz if a Silead touchscreen is presentHans de Goede
Many cheap devices use Silead touchscreen controllers. Testing has shown repeatedly that these touchscreen controllers work fine at 400KHz, but for unknown reasons do not work properly at 100KHz. This has been seen on both ARM and x86 devices using totally different i2c controllers. On some devices the ACPI tables list another device at the same I2C-bus as only being capable of 100KHz, testing has shown that these other devices work fine at 400KHz (as can be expected of any recent I2C hw). This commit makes i2c_acpi_find_bus_speed() always return 400KHz if a Silead touchscreen controller is present, fixing the touchscreen not working on devices which ACPI tables' wrongly list another device on the same bus as only being capable of 100KHz. Specifically this fixes the touchscreen on the Jumper EZpad 6 m4 not working. Reported-by: youling 257 <youling257@gmail.com> Tested-by: youling 257 <youling257@gmail.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> [wsa: rewording warning a little] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2019-10-24i2c: stm32f7: remove warning when compiling with W=1Alain Volmat
Remove the following warning: drivers/i2c/busses/i2c-stm32f7.c:315: warning: cannot understand function prototype: 'struct stm32f7_i2c_spec i2c_specs[] = Replace a comment starting with /** by simply /* to avoid having it interpreted as a kernel-doc comment. Fixes: aeb068c57214 ("i2c: i2c-stm32f7: add driver") Signed-off-by: Alain Volmat <alain.volmat@st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-10-24i2c: stm32f7: fix a race in slave mode with arbitration loss irqFabrice Gasnier
When in slave mode, an arbitration loss (ARLO) may be detected before the slave had a chance to detect the stop condition (STOPF in ISR). This is seen when two master + slave adapters switch their roles. It provokes the i2c bus to be stuck, busy as SCL line is stretched. - the I2C_SLAVE_STOP event is never generated due to STOPF flag is set but don't generate an irq (race with ARLO irq, STOPIE is masked). STOPF flag remains set until next master xfer (e.g. when STOPIE irq get unmasked). In this case, completion is generated too early: immediately upon new transfer request (then it doesn't send all data). - Some data get stuck in TXDR register. As a consequence, the controller stretches the SCL line: the bus gets busy until a future master transfer triggers the bus busy / recovery mechanism (this can take time... and may never happen at all) So choice is to let the STOPF being detected by the slave isr handler, to properly handle this stop condition. E.g. don't mask IRQs in error handler, when the slave is running. Fixes: 60d609f30de2 ("i2c: i2c-stm32f7: Add slave support") Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>