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2024-07-05i2c: ocores: set IACK bit after core is enabledGrygorii Tertychnyi
commit 5a72477273066b5b357801ab2d315ef14949d402 upstream. Setting IACK bit when core is disabled does not clear the "Interrupt Flag" bit in the status register, and the interrupt remains pending. Sometimes it causes failure for the very first message transfer, that is usually a device probe. Hence, set IACK bit after core is enabled to clear pending interrupt. Fixes: 18f98b1e3147 ("[PATCH] i2c: New bus driver for the OpenCores I2C controller") Signed-off-by: Grygorii Tertychnyi <grygorii.tertychnyi@leica-geosystems.com> Acked-by: Peter Korsgaard <peter@korsgaard.com> Cc: stable@vger.kernel.org Signed-off-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05i2c: designware: Fix the functionality flags of the slave-only interfaceJean Delvare
[ Upstream commit cbf3fb5b29e99e3689d63a88c3cddbffa1b8de99 ] When an I2C adapter acts only as a slave, it should not claim to support I2C master capabilities. Fixes: 5b6d721b266a ("i2c: designware: enable SLAVE in platform module") Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Luis Oliveira <lolivei@synopsys.com> Cc: Jarkko Nikula <jarkko.nikula@linux.intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Jan Dabros <jsd@semihalf.com> Cc: Andi Shyti <andi.shyti@kernel.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-07-05i2c: at91: Fix the functionality flags of the slave-only interfaceJean Delvare
[ Upstream commit d6d5645e5fc1233a7ba950de4a72981c394a2557 ] When an I2C adapter acts only as a slave, it should not claim to support I2C master capabilities. Fixes: 9d3ca54b550c ("i2c: at91: added slave mode support") Signed-off-by: Jean Delvare <jdelvare@suse.de> Cc: Juergen Fitschen <me@jue.yt> Cc: Ludovic Desroches <ludovic.desroches@microchip.com> Cc: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> Cc: Andi Shyti <andi.shyti@kernel.org> Cc: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com> Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev> Signed-off-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-05-02i2c: smbus: fix NULL function pointer dereferenceWolfram Sang
[ Upstream commit 91811a31b68d3765b3065f4bb6d7d6d84a7cfc9f ] Baruch reported an OOPS when using the designware controller as target only. Target-only modes break the assumption of one transfer function always being available. Fix this by always checking the pointer in __i2c_transfer. Reported-by: Baruch Siach <baruch@tkos.co.il> Closes: https://lore.kernel.org/r/4269631780e5ba789cf1ae391eec1b959def7d99.1712761976.git.baruch@tkos.co.il Fixes: 4b1acc43331d ("i2c: core changes for slave support") [wsa: dropped the simplification in core-smbus to avoid theoretical regressions] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-23i2c: i801: Fix block process call transactionsJean Delvare
[ Upstream commit c1c9d0f6f7f1dbf29db996bd8e166242843a5f21 ] According to the Intel datasheets, software must reset the block buffer index twice for block process call transactions: once before writing the outgoing data to the buffer, and once again before reading the incoming data from the buffer. The driver is currently missing the second reset, causing the wrong portion of the block buffer to be read. Signed-off-by: Jean Delvare <jdelvare@suse.de> Reported-by: Piotr Zakowski <piotr.zakowski@intel.com> Closes: https://lore.kernel.org/linux-i2c/20240213120553.7b0ab120@endymion.delvare/ Fixes: 315cd67c9453 ("i2c: i801: Add Block Write-Block Read Process Call support") Reviewed-by: Alexander Sverdlin <alexander.sverdlin@gmail.com> Signed-off-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-23i2c: i801: Remove i801_set_block_buffer_modeHeiner Kallweit
[ Upstream commit 1e1d6582f483a4dba4ea03445e6f2f05d9de5bcf ] If FEATURE_BLOCK_BUFFER is set then bit SMBAUXCTL_E32B is supported and there's no benefit in reading it back. Origin of this check seems to be 14 yrs ago when people were not completely sure which chip versions support the block buffer mode. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Tested-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@kernel.org> Stable-dep-of: c1c9d0f6f7f1 ("i2c: i801: Fix block process call transactions") Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25i2c: s3c24xx: fix transferring more than one message in polling modeMarek Szyprowski
[ Upstream commit 990489e1042c6c5d6bccf56deca68f8dbeed8180 ] To properly handle ACK on the bus when transferring more than one message in polling mode, move the polling handling loop from s3c24xx_i2c_message_start() to s3c24xx_i2c_doxfer(). This way i2c_s3c_irq_nextbyte() is always executed till the end, properly acknowledging the IRQ bits and no recursive calls to i2c_s3c_irq_nextbyte() are made. While touching this, also fix finishing transfers in polling mode by using common code path and always waiting for the bus to become idle and disabled. Fixes: 117053f77a5a ("i2c: s3c2410: Add polling mode support") Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25i2c: s3c24xx: fix read transfers in polling modeMarek Szyprowski
[ Upstream commit 0d9cf23ed55d7ba3ab26d617a3ae507863674c8f ] To properly handle read transfers in polling mode, no waiting for the ACK state is needed as it will never come. Just wait a bit to ensure start state is on the bus and continue processing next bytes. Fixes: 117053f77a5a ("i2c: s3c2410: Add polling mode support") Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com> Reviewed-by: Chanho Park <chanho61.park@samsung.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-25i2c: rk3x: fix potential spinlock recursion on pollJensen Huang
[ Upstream commit 19cde9c92b8d3b7ee555d0da3bcb0232d3a784f4 ] Possible deadlock scenario (on reboot): rk3x_i2c_xfer_common(polling) -> rk3x_i2c_wait_xfer_poll() -> rk3x_i2c_irq(0, i2c); --> spin_lock(&i2c->lock); ... <rk3x i2c interrupt> -> rk3x_i2c_irq(0, i2c); --> spin_lock(&i2c->lock); (deadlock here) Store the IRQ number and disable/enable it around the polling transfer. This patch has been tested on NanoPC-T4. Signed-off-by: Jensen Huang <jensenhuang@friendlyarm.com> Reviewed-by: Heiko Stuebner <heiko@sntech.de> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-15i2c: core: Fix atomic xfer check for non-preempt configBenjamin Bara
commit a3368e1186e3ce8e38f78cbca019622095b1f331 upstream. Since commit aa49c90894d0 ("i2c: core: Run atomic i2c xfer when !preemptible"), the whole reboot/power off sequence on non-preempt kernels is using atomic i2c xfer, as !preemptible() always results to 1. During device_shutdown(), the i2c might be used a lot and not all busses have implemented an atomic xfer handler. This results in a lot of avoidable noise, like: [ 12.687169] No atomic I2C transfer handler for 'i2c-0' [ 12.692313] WARNING: CPU: 6 PID: 275 at drivers/i2c/i2c-core.h:40 i2c_smbus_xfer+0x100/0x118 ... Fix this by allowing non-atomic xfer when the interrupts are enabled, as it was before. Link: https://lore.kernel.org/r/20231222230106.73f030a5@yea Link: https://lore.kernel.org/r/20240102150350.3180741-1-mwalle@kernel.org Link: https://lore.kernel.org/linux-i2c/13271b9b-4132-46ef-abf8-2c311967bb46@mailbox.org/ Fixes: aa49c90894d0 ("i2c: core: Run atomic i2c xfer when !preemptible") Cc: stable@vger.kernel.org # v5.2+ Signed-off-by: Benjamin Bara <benjamin.bara@skidata.com> Tested-by: Michael Walle <mwalle@kernel.org> Tested-by: Tor Vic <torvic9@mailbox.org> [wsa: removed a comment which needs more work, code is ok] Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-05i2c: aspeed: Handle the coalesced stop conditions with the start conditions.Quan Nguyen
[ Upstream commit b4cc1cbba5195a4dd497cf2f8f09e7807977d543 ] Some masters may drive the transfers with low enough latency between the nak/stop phase of the current command and the start/address phase of the following command that the interrupts are coalesced by the time we process them. Handle the stop conditions before processing SLAVE_MATCH to fix the complaints that sometimes occur below. "aspeed-i2c-bus 1e78a040.i2c-bus: irq handled != irq. Expected 0x00000086, but was 0x00000084" Fixes: f9eb91350bb2 ("i2c: aspeed: added slave support for Aspeed I2C driver") Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com> Reviewed-by: Andrew Jeffery <andrew@codeconstruct.com.au> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-12-13i2c: designware: Fix corrupted memory seen in the ISRJan Bottorff
[ Upstream commit f726eaa787e9f9bc858c902d18a09af6bcbfcdaf ] When running on a many core ARM64 server, errors were happening in the ISR that looked like corrupted memory. These corruptions would fix themselves if small delays were inserted in the ISR. Errors reported by the driver included "i2c_designware APMC0D0F:00: i2c_dw_xfer_msg: invalid target address" and "i2c_designware APMC0D0F:00:controller timed out" during in-band IPMI SSIF stress tests. The problem was determined to be memory writes in the driver were not becoming visible to all cores when execution rapidly shifted between cores, like when a register write immediately triggers an ISR. Processors with weak memory ordering, like ARM64, make no guarantees about the order normal memory writes become globally visible, unless barrier instructions are used to control ordering. To solve this, regmap accessor functions configured by this driver were changed to use non-relaxed forms of the low-level register access functions, which include a barrier on platforms that require it. This assures memory writes before a controller register access are visible to all cores. The community concluded defaulting to correct operation outweighed defaulting to the small performance gains from using relaxed access functions. Being a low speed device added weight to this choice of default register access behavior. Signed-off-by: Jan Bottorff <janb@os.amperecomputing.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Serge Semin <fancer.lancer@gmail.com> Reviewed-by: Serge Semin <fancer.lancer@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28i2c: i801: fix potential race in i801_block_transaction_byte_by_byteHeiner Kallweit
commit f78ca48a8ba9cdec96e8839351e49eec3233b177 upstream. Currently we set SMBHSTCNT_LAST_BYTE only after the host has started receiving the last byte. If we get e.g. preempted before setting SMBHSTCNT_LAST_BYTE, the host may be finished with receiving the byte before SMBHSTCNT_LAST_BYTE is set. Therefore change the code to set SMBHSTCNT_LAST_BYTE before writing SMBHSTSTS_BYTE_DONE for the byte before the last byte. Now the code is also consistent with what we do in i801_isr_byte_done(). Reported-by: Jean Delvare <jdelvare@suse.com> Closes: https://lore.kernel.org/linux-i2c/20230828152747.09444625@endymion.delvare/ Cc: stable@vger.kernel.org Acked-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28i2c: designware: Disable TX_EMPTY irq while waiting for block length byteTam Nguyen
commit e8183fa10c25c7b3c20670bf2b430ddcc1ee03c0 upstream. During SMBus block data read process, we have seen high interrupt rate because of TX_EMPTY irq status while waiting for block length byte (the first data byte after the address phase). The interrupt handler does not do anything because the internal state is kept as STATUS_WRITE_IN_PROGRESS. Hence, we should disable TX_EMPTY IRQ until I2C DesignWare receives first data byte from I2C device, then re-enable it to resume SMBus transaction. It takes 0.789 ms for host to receive data length from slave. Without the patch, i2c_dw_isr() is called 99 times by TX_EMPTY interrupt. And it is none after applying the patch. Cc: stable@vger.kernel.org Co-developed-by: Chuong Tran <chuong@os.amperecomputing.com> Signed-off-by: Chuong Tran <chuong@os.amperecomputing.com> Signed-off-by: Tam Nguyen <tamnguyenchi@os.amperecomputing.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Serge Semin <fancer.lancer@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28i2c: core: Run atomic i2c xfer when !preemptibleBenjamin Bara
commit aa49c90894d06e18a1ee7c095edbd2f37c232d02 upstream. Since bae1d3a05a8b, i2c transfers are non-atomic if preemption is disabled. However, non-atomic i2c transfers require preemption (e.g. in wait_for_completion() while waiting for the DMA). panic() calls preempt_disable_notrace() before calling emergency_restart(). Therefore, if an i2c device is used for the restart, the xfer should be atomic. This avoids warnings like: [ 12.667612] WARNING: CPU: 1 PID: 1 at kernel/rcu/tree_plugin.h:318 rcu_note_context_switch+0x33c/0x6b0 [ 12.676926] Voluntary context switch within RCU read-side critical section! ... [ 12.742376] schedule_timeout from wait_for_completion_timeout+0x90/0x114 [ 12.749179] wait_for_completion_timeout from tegra_i2c_wait_completion+0x40/0x70 ... [ 12.994527] atomic_notifier_call_chain from machine_restart+0x34/0x58 [ 13.001050] machine_restart from panic+0x2a8/0x32c Use !preemptible() instead, which is basically the same check as pre-v5.2. Fixes: bae1d3a05a8b ("i2c: core: remove use of in_atomic()") Cc: stable@vger.kernel.org # v5.2+ Suggested-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Acked-by: Wolfram Sang <wsa@kernel.org> Reviewed-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Tested-by: Nishanth Menon <nm@ti.com> Signed-off-by: Benjamin Bara <benjamin.bara@skidata.com> Link: https://lore.kernel.org/r/20230327-tegra-pmic-reboot-v7-2-18699d5dcd76@skidata.com Signed-off-by: Lee Jones <lee@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28i2c: sun6i-p2wi: Prevent potential division by zeroAxel Lin
[ Upstream commit 5ac61d26b8baff5b2e5a9f3dc1ef63297e4b53e7 ] Make sure we don't OOPS in case clock-frequency is set to 0 in a DT. The variable set here is later used as a divisor. Signed-off-by: Axel Lin <axel.lin@ingics.com> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-08i2c: aspeed: Fix i2c bus hang in slave readJian Zhang
commit 54f1840ddee9bbdc8dd89fbbfdfa632401244146 upstream. When the `CONFIG_I2C_SLAVE` option is enabled and the device operates as a slave, a situation arises where the master sends a START signal without the accompanying STOP signal. This action results in a persistent I2C bus timeout. The core issue stems from the fact that the i2c controller remains in a slave read state without a timeout mechanism. As a consequence, the bus perpetually experiences timeouts. In this case, the i2c bus will be reset, but the slave_state reset is missing. Fixes: fee465150b45 ("i2c: aspeed: Reset the i2c controller when timeout occurs") Signed-off-by: Jian Zhang <zhangjian.3032@bytedance.com> Acked-by: Andi Shyti <andi.shyti@kernel.org> Tested-by: Andrew Jeffery <andrew@codeconstruct.com.au> Reviewed-by: Andrew Jeffery <andrew@codeconstruct.com.au> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08i2c: stm32f7: Fix PEC handling in case of SMBUS transfersAlain Volmat
commit c896ff2dd8f30a6b0a922c83a96f6d43f05f0e92 upstream. In case of SMBUS byte read with PEC enabled, the whole transfer is split into two commands. A first write command, followed by a read command. The write command does not have any PEC byte and a PEC byte is appended at the end of the read command. (cf Read byte protocol with PEC in SMBUS specification) Within the STM32 I2C controller, handling (either sending or receiving) of the PEC byte is done via the PECBYTE bit in register CR2. Currently, the PECBYTE is set at the beginning of a transfer, which lead to sending a PEC byte at the end of the write command (hence losing the real last byte), and also does not check the PEC byte received during the read command. This patch corrects the function stm32f7_i2c_smbus_xfer_msg in order to only set the PECBYTE during the read command. Fixes: 9e48155f6bfe ("i2c: i2c-stm32f7: Add initial SMBus protocols support") Signed-off-by: Alain Volmat <alain.volmat@foss.st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@foss.st.com> Acked-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08i2c: muxes: i2c-demux-pinctrl: Use of_get_i2c_adapter_by_node()Herve Codina
commit 0fb118de5003028ad092a4e66fc6d07b86c3bc94 upstream. i2c-demux-pinctrl uses the pair of_find_i2c_adapter_by_node() / i2c_put_adapter(). These pair alone is not correct to properly lock the I2C parent adapter. Indeed, i2c_put_adapter() decrements the module refcount while of_find_i2c_adapter_by_node() does not increment it. This leads to an underflow of the parent module refcount. Use the dedicated function, of_get_i2c_adapter_by_node(), to handle correctly the module refcount. Fixes: 50a5ba876908 ("i2c: mux: demux-pinctrl: add driver") Signed-off-by: Herve Codina <herve.codina@bootlin.com> Cc: stable@vger.kernel.org Acked-by: Peter Rosin <peda@axentia.se> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08i2c: muxes: i2c-mux-gpmux: Use of_get_i2c_adapter_by_node()Herve Codina
commit 3dc0ec46f6e7511fc4fdf6b6cda439382bc957f1 upstream. i2c-mux-gpmux uses the pair of_find_i2c_adapter_by_node() / i2c_put_adapter(). These pair alone is not correct to properly lock the I2C parent adapter. Indeed, i2c_put_adapter() decrements the module refcount while of_find_i2c_adapter_by_node() does not increment it. This leads to an underflow of the parent module refcount. Use the dedicated function, of_get_i2c_adapter_by_node(), to handle correctly the module refcount. Fixes: ac8498f0ce53 ("i2c: i2c-mux-gpmux: new driver") Signed-off-by: Herve Codina <herve.codina@bootlin.com> Cc: stable@vger.kernel.org Acked-by: Peter Rosin <peda@axentia.se> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-08i2c: muxes: i2c-mux-pinctrl: Use of_get_i2c_adapter_by_node()Herve Codina
commit 3171d37b58a76e1febbf3f4af2d06234a98cf88b upstream. i2c-mux-pinctrl uses the pair of_find_i2c_adapter_by_node() / i2c_put_adapter(). These pair alone is not correct to properly lock the I2C parent adapter. Indeed, i2c_put_adapter() decrements the module refcount while of_find_i2c_adapter_by_node() does not increment it. This leads to an underflow of the parent module refcount. Use the dedicated function, of_get_i2c_adapter_by_node(), to handle correctly the module refcount. Fixes: c4aee3e1b0de ("i2c: mux: pinctrl: remove platform_data") Signed-off-by: Herve Codina <herve.codina@bootlin.com> Cc: stable@vger.kernel.org Acked-by: Peter Rosin <peda@axentia.se> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-25i2c: mux: Avoid potential false error message in i2c_mux_add_adapterHeiner Kallweit
[ Upstream commit b13e59e74ff71a1004e0508107e91e9a84fd7388 ] I2C_CLASS_DEPRECATED is a flag and not an actual class. There's nothing speaking against both, parent and child, having I2C_CLASS_DEPRECATED set. Therefore exclude it from the check. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Acked-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10i2c: i801: unregister tco_pdev in i801_probe() error pathHeiner Kallweit
commit 3914784553f68c931fc666dbe7e86fe881aada38 upstream. We have to unregister tco_pdev also if i2c_add_adapter() fails. Fixes: 9424693035a5 ("i2c: i801: Create iTCO device on newer Intel PCHs") Cc: stable@vger.kernel.org Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-10i2c: npcm7xx: Fix callback completion orderingWilliam A. Kennington III
[ Upstream commit 92e73d807b68b2214fcafca4e130b5300a9d4b3c ] Sometimes, our completions race with new master transfers and override the bus->operation and bus->master_or_slave variables. This causes transactions to timeout and kernel crashes less frequently. To remedy this, we re-order all completions to the very end of the function. Fixes: 56a1485b102e ("i2c: npcm7xx: Add Nuvoton NPCM I2C controller driver") Signed-off-by: William A. Kennington III <william@wkennington.com> Reviewed-by: Tali Perry <tali.perry1@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10i2c: mux: demux-pinctrl: check the return value of devm_kstrdup()Xiaoke Wang
[ Upstream commit 7c0195fa9a9e263df204963f88a22b21688ffb66 ] devm_kstrdup() returns pointer to allocated string on success, NULL on failure. So it is better to check the return value of it. Fixes: e35478eac030 ("i2c: mux: demux-pinctrl: run properly with multiple instances") Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-09-23i2c: aspeed: Reset the i2c controller when timeout occursTommy Huang
commit fee465150b458351b6d9b9f66084f3cc3022b88b upstream. Reset the i2c controller when an i2c transfer timeout occurs. The remaining interrupts and device should be reset to avoid unpredictable controller behavior. Fixes: 2e57b7cebb98 ("i2c: aspeed: Add multi-master use case support") Cc: <stable@vger.kernel.org> # v5.1+ Signed-off-by: Tommy Huang <tommy_huang@aspeedtech.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-26i2c: designware: Handle invalid SMBus block data response length valueTam Nguyen
commit 69f035c480d76f12bf061148ccfd578e1099e5fc upstream. In the I2C_FUNC_SMBUS_BLOCK_DATA case, the invalid length byte value (outside of 1-32) of the SMBus block data response from the Slave device is not correctly handled by the I2C Designware driver. In case IC_EMPTYFIFO_HOLD_MASTER_EN==1, which cannot be detected from the registers, the Master can be disabled only if the STOP bit is set. Without STOP bit set, the Master remains active, holding the bus until receiving a block data response length. This hangs the bus and is unrecoverable. Avoid this by issuing another dump read to reach the stop condition when an invalid length byte is received. Cc: stable@vger.kernel.org Signed-off-by: Tam Nguyen <tamnguyenchi@os.amperecomputing.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Link: https://lore.kernel.org/r/20230726080001.337353-3-tamnguyenchi@os.amperecomputing.com Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-26i2c: bcm-iproc: Fix bcm_iproc_i2c_isr deadlock issueChengfeng Ye
commit 4caf4cb1eaed469742ef719f2cc024b1ec3fa9e6 upstream. iproc_i2c_rd_reg() and iproc_i2c_wr_reg() are called from both interrupt context (e.g. bcm_iproc_i2c_isr) and process context (e.g. bcm_iproc_i2c_suspend). Therefore, interrupts should be disabled to avoid potential deadlock. To prevent this scenario, use spin_lock_irqsave(). Fixes: 9a1038728037 ("i2c: iproc: add NIC I2C support") Signed-off-by: Chengfeng Ye <dg573847474@gmail.com> Acked-by: Ray Jui <ray.jui@broadcom.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-11i2c: nomadik: Remove a useless call in the remove functionChristophe JAILLET
[ Upstream commit 05f933d5f7318b03ff2028c1704dc867ac16f2c7 ] Since commit 235602146ec9 ("i2c-nomadik: turn the platform driver to an amba driver"), there is no more request_mem_region() call in this driver. So remove the release_mem_region() call from the remove function which is likely a left over. Fixes: 235602146ec9 ("i2c-nomadik: turn the platform driver to an amba driver") Cc: <stable@vger.kernel.org> # v3.6+ Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> 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>
2023-08-11i2c: nomadik: Use devm_clk_get_enabled()Andi Shyti
[ Upstream commit 9c7174db4cdd111e10d19eed5c36fd978a14c8a2 ] Replace the pair of functions, devm_clk_get() and clk_prepare_enable(), with a single function devm_clk_get_enabled(). Signed-off-by: Andi Shyti <andi.shyti@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Stable-dep-of: 05f933d5f731 ("i2c: nomadik: Remove a useless call in the remove function") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11i2c: nomadik: Remove unnecessary goto labelAndi Shyti
[ Upstream commit 1c5d33fff0d375e4ab7c4261dc62a286babbb4c6 ] The err_no_mem goto label doesn't do anything. Remove it. Signed-off-by: Andi Shyti <andi.shyti@kernel.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Stable-dep-of: 05f933d5f731 ("i2c: nomadik: Remove a useless call in the remove function") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11i2c: Improve size determinationsMarkus Elfring
[ Upstream commit 06e989578232da33a7fe96b04191b862af8b2cec ] Replace the specification of a data structure by a pointer dereference as the parameter for the operator "sizeof" to make the corresponding size determination a bit safer according to the Linux coding style convention. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Wolfram Sang <wsa@kernel.org> Stable-dep-of: 05f933d5f731 ("i2c: nomadik: Remove a useless call in the remove function") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11i2c: Delete error messages for failed memory allocationsMarkus Elfring
[ Upstream commit 6b3b21a8542fd2fb6ffc61bc13b9419f0c58ebad ] These issues were detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Wolfram Sang <wsa@kernel.org> Stable-dep-of: 05f933d5f731 ("i2c: nomadik: Remove a useless call in the remove function") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27i2c: qup: Add missing unwind goto in qup_i2c_probe()Shuai Jiang
commit cd9489623c29aa2f8cc07088168afb6e0d5ef06d upstream. Smatch Warns: drivers/i2c/busses/i2c-qup.c:1784 qup_i2c_probe() warn: missing unwind goto? The goto label "fail_runtime" and "fail" will disable qup->pclk, but here qup->pclk failed to obtain, in order to be consistent, change the direct return to goto label "fail_dma". Fixes: 9cedf3b2f099 ("i2c: qup: Add bam dma capabilities") Signed-off-by: Shuai Jiang <d202180596@hust.edu.cn> Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Cc: <stable@vger.kernel.org> # v4.6+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-27i2c: xiic: Don't try to handle more interrupt events after errorRobert Hancock
[ Upstream commit cb6e45c9a0ad9e0f8664fd06db0227d185dc76ab ] In xiic_process, it is possible that error events such as arbitration lost or TX error can be raised in conjunction with other interrupt flags such as TX FIFO empty or bus not busy. Error events result in the controller being reset and the error returned to the calling request, but the function could potentially try to keep handling the other events, such as by writing more messages into the TX FIFO. Since the transaction has already failed, this is not helpful and will just cause issues. This problem has been present ever since: commit 7f9906bd7f72 ("i2c: xiic: Service all interrupts in isr") which allowed non-error events to be handled after errors, but became more obvious after: commit 743e227a8959 ("i2c: xiic: Defer xiic_wakeup() and __xiic_start_xfer() in xiic_process()") which reworked the code to add a WARN_ON which triggers if both the xfer_more and wakeup_req flags were set, since this combination is not supposed to happen, but was occurring in this scenario. Skip further interrupt handling after error flags are detected to avoid this problem. Fixes: 7f9906bd7f72 ("i2c: xiic: Service all interrupts in isr") Signed-off-by: Robert Hancock <robert.hancock@calian.com> Acked-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-07-27i2c: xiic: Defer xiic_wakeup() and __xiic_start_xfer() in xiic_process()Marek Vasut
[ Upstream commit 743e227a895923c37a333eb2ebf3e391f00c406d ] The __xiic_start_xfer() manipulates the interrupt flags, xiic_wakeup() may result in return from xiic_xfer() early. Defer both to the end of the xiic_process() interrupt thread, so that they are executed after all the other interrupt bits handling completed and once it completely safe to perform changes to the interrupt bits in the hardware. Signed-off-by: Marek Vasut <marex@denx.de> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Stable-dep-of: cb6e45c9a0ad ("i2c: xiic: Don't try to handle more interrupt events after error") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-28i2c: imx-lpi2c: fix type char overflow issue when calculating the clock cycleClark Wang
[ Upstream commit e69b9bc170c6d93ee375a5cbfd15f74c0fb59bdd ] Claim clkhi and clklo as integer type to avoid possible calculation errors caused by data overflow. Fixes: a55fa9d0e42e ("i2c: imx-lpi2c: add low power i2c bus driver") Signed-off-by: Clark Wang <xiaoning.wang@nxp.com> Signed-off-by: Carlos Song <carlos.song@nxp.com> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-14i2c: sprd: Delete i2c adapter in .remove's error pathUwe Kleine-König
[ Upstream commit ca0aa17f2db3468fd017038d23a78e17388e2f67 ] If pm runtime resume fails the .remove callback used to exit early. This resulted in an error message by the driver core but the device gets removed anyhow. This lets the registered i2c adapter stay around with an unbound parent device. So only skip clk disabling if resume failed, but do delete the adapter. Fixes: 8b9ec0719834 ("i2c: Add Spreadtrum I2C controller driver") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17i2c: cadence: cdns_i2c_master_xfer(): Fix runtime PM leak on error pathLars-Peter Clausen
[ Upstream commit ae1664f04f504a998737f5bb563f16b44357bcca ] The cdns_i2c_master_xfer() function gets a runtime PM reference when the function is entered. This reference is released when the function is exited. There is currently one error path where the function exits directly, which leads to a leak of the runtime PM reference. Make sure that this error path also releases the runtime PM reference. Fixes: 1a351b10b967 ("i2c: cadence: Added slave support") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Michal Simek <michal.simek@amd.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17i2c: omap: Fix standard mode false ACK readingsReid Tonking
commit c770657bd2611b077ec1e7b1fe6aa92f249399bd upstream. Using standard mode, rare false ACK responses were appearing with i2cdetect tool. This was happening due to NACK interrupt triggering ISR thread before register access interrupt was ready. Removing the NACK interrupt's ability to trigger ISR thread lets register access ready interrupt do this instead. Cc: <stable@vger.kernel.org> # v3.7+ Fixes: 3b2f8f82dad7 ("i2c: omap: switch to threaded IRQ support") Signed-off-by: Reid Tonking <reidt@ti.com> Acked-by: Vignesh Raghavendra <vigneshr@ti.com> Reviewed-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-20i2c: ocores: generate stop condition after timeout in polling modeGregor Herburger
[ Upstream commit f8160d3b35fc94491bb0cb974dbda310ef96c0e2 ] In polling mode, no stop condition is generated after a timeout. This causes SCL to remain low and thereby block the bus. If this happens during a transfer it can cause slaves to misinterpret the subsequent transfer and return wrong values. To solve this, pass the ETIMEDOUT error up from ocores_process_polling() instead of setting STATE_ERROR directly. The caller is adjusted to call ocores_process_timeout() on error both in polling and in IRQ mode, which will set STATE_ERROR and generate a stop condition. Fixes: 69c8c0c0efa8 ("i2c: ocores: add polling interface") Signed-off-by: Gregor Herburger <gregor.herburger@tq-group.com> Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> Acked-by: Peter Korsgaard <peter@korsgaard.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Federico Vaga <federico.vaga@cern.ch> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-20i2c: imx-lpi2c: clean rx/tx buffers upon new messageAlexander Stein
[ Upstream commit 987dd36c0141f6ab9f0fbf14d6b2ec3342dedb2f ] When start sending a new message clear the Rx & Tx buffer pointers in order to avoid using stale pointers. Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com> Tested-by: Emanuele Ghidoli <emanuele.ghidoli@toradex.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-04-05i2c: xgene-slimpro: Fix out-of-bounds bug in xgene_slimpro_i2c_xfer()Wei Chen
commit 92fbb6d1296f81f41f65effd7f5f8c0f74943d15 upstream. The data->block[0] variable comes from user and is a number between 0-255. Without proper check, the variable may be very large to cause an out-of-bounds when performing memcpy in slimpro_i2c_blkwr. Fix this bug by checking the value of writelen. Fixes: f6505fbabc42 ("i2c: add SLIMpro I2C device driver on APM X-Gene platform") Signed-off-by: Wei Chen <harperchen1110@gmail.com> Cc: stable@vger.kernel.org Reviewed-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05i2c: imx-lpi2c: check only for enabled interrupt flagsAlexander Stein
[ Upstream commit 1c7885004567e8951d65a983be095f254dd20bef ] When reading from I2C, the Tx watermark is set to 0. Unfortunately the TDF (transmit data flag) is enabled when Tx FIFO entries is equal or less than watermark. So it is set in every case, hence the reset default of 1. This results in the MSR_RDF _and_ MSR_TDF flags to be set thus trying to send Tx data on a read message. Mask the IRQ status to filter for wanted flags only. Fixes: a55fa9d0e42e ("i2c: imx-lpi2c: add low power i2c bus driver") Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com> Tested-by: Emanuele Ghidoli <emanuele.ghidoli@toradex.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-15i2c: rk3x: fix a bunch of kernel-doc warningsRandy Dunlap
[ Upstream commit 0582d984793d30442da88fe458674502bad1ad29 ] Fix multiple W=1 kernel-doc warnings in i2c-rk3x.c: drivers/i2c/busses/i2c-rk3x.c:83: warning: missing initial short description on line: * struct i2c_spec_values: drivers/i2c/busses/i2c-rk3x.c:139: warning: missing initial short description on line: * struct rk3x_i2c_calced_timings: drivers/i2c/busses/i2c-rk3x.c:162: warning: missing initial short description on line: * struct rk3x_i2c_soc_data: drivers/i2c/busses/i2c-rk3x.c:242: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Generate a START condition, which triggers a REG_INT_START interrupt. drivers/i2c/busses/i2c-rk3x.c:261: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Generate a STOP condition, which triggers a REG_INT_STOP interrupt. drivers/i2c/busses/i2c-rk3x.c:304: warning: expecting prototype for Setup a read according to i2c(). Prototype was for rk3x_i2c_prepare_read() instead drivers/i2c/busses/i2c-rk3x.c:335: warning: expecting prototype for Fill the transmit buffer with data from i2c(). Prototype was for rk3x_i2c_fill_transmit_buf() instead drivers/i2c/busses/i2c-rk3x.c:535: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Get timing values of I2C specification drivers/i2c/busses/i2c-rk3x.c:552: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Calculate divider values for desired SCL frequency drivers/i2c/busses/i2c-rk3x.c:713: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Calculate timing values for desired SCL frequency drivers/i2c/busses/i2c-rk3x.c:963: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst * Setup I2C registers for an I2C operation specified by msgs, num. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-15i2c: mxs: suppress probe-deferral error messageStefan Wahren
[ Upstream commit 78a4471fa1a76a8bef4919105de67660a89a1e9b ] During boot of I2SE Duckbill the kernel log contains a confusing error: Failed to request dma This is caused by i2c-mxs tries to request a not yet available DMA channel (-EPROBE_DEFER). So suppress this message by using dev_err_probe(). Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Reviewed-by: Fabio Estevam <festevam@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01i2c: designware: use casting of u64 in clock multiplication to avoid overflowLareine Khawaly
[ Upstream commit c8c37bc514514999e62a17e95160ed9ebf75ca8d ] In functions i2c_dw_scl_lcnt() and i2c_dw_scl_hcnt() may have overflow by depending on the values of the given parameters including the ic_clk. For example in our use case where ic_clk is larger than one million, multiplication of ic_clk * 4700 will result in 32 bit overflow. Add cast of u64 to the calculation to avoid multiplication overflow, and use the corresponding define for divide. Fixes: 2373f6b9744d ("i2c-designware: split of i2c-designware.c into core and bus specific parts") Signed-off-by: Lareine Khawaly <lareine@amazon.com> Signed-off-by: Hanna Hawa <hhhawa@amazon.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-01i2c: designware: Use DIV_ROUND_CLOSEST() macroAndy Shevchenko
[ Upstream commit c045214a0f31dd5d6be716ed2f119b57b6c5d3a2 ] Instead of open-coding DIV_ROUND_CLOSEST() and similar use the macros directly. While at it, replace numbers with predefined SI metric prefixes. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Stable-dep-of: c8c37bc51451 ("i2c: designware: use casting of u64 in clock multiplication to avoid overflow") Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14i2c: ismt: Fix an out-of-bounds bug in ismt_access()Zheyu Ma
[ Upstream commit 39244cc754829bf707dccd12e2ce37510f5b1f8d ] When the driver does not check the data from the user, the variable 'data->block[0]' may be very large to cause an out-of-bounds bug. The following log can reveal it: [ 33.995542] i2c i2c-1: ioctl, cmd=0x720, arg=0x7ffcb3dc3a20 [ 33.995978] ismt_smbus 0000:00:05.0: I2C_SMBUS_BLOCK_DATA: WRITE [ 33.996475] ================================================================== [ 33.996995] BUG: KASAN: out-of-bounds in ismt_access.cold+0x374/0x214b [ 33.997473] Read of size 18446744073709551615 at addr ffff88810efcfdb1 by task ismt_poc/485 [ 33.999450] Call Trace: [ 34.001849] memcpy+0x20/0x60 [ 34.002077] ismt_access.cold+0x374/0x214b [ 34.003382] __i2c_smbus_xfer+0x44f/0xfb0 [ 34.004007] i2c_smbus_xfer+0x10a/0x390 [ 34.004291] i2cdev_ioctl_smbus+0x2c8/0x710 [ 34.005196] i2cdev_ioctl+0x5ec/0x74c Fix this bug by checking the size of 'data->block[0]' first. Fixes: 13f35ac14cd0 ("i2c: Adding support for Intel iSMT SMBus 2.0 host controller") Signed-off-by: Zheyu Ma <zheyuma97@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-14i2c: mux: reg: check return value after calling platform_get_resource()Yang Yingliang
[ Upstream commit 2d47b79d2bd39cc6369eccf94a06568d84c906ae ] It will cause null-ptr-deref in resource_size(), if platform_get_resource() returns NULL, move calling resource_size() after devm_ioremap_resource() that will check 'res' to avoid null-ptr-deref. And use devm_platform_get_and_ioremap_resource() to simplify code. Fixes: b3fdd32799d8 ("i2c: mux: Add register-based mux i2c-mux-reg") Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>