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2022-05-21i2c: xiic: Correct the datatype for rx_watermarkShubhrajyoti Datta1-2/+2
The message length data type should be u16 as per the i2c_msg structure. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Acked-by: Michal Simek <michal.simek@amd.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-05-14i2c: xiic: Fix Tx Interrupt path for grouped messagesRaviteja Narayanam1-18/+20
When a group of messages are sent from user space as a set, if the last message has less than Tx FIFO DEPTH number of bytes to transfer, Tx half empty interrupt is triggered continuously from the hardware. It is due to Bus not busy interrupt coming along with Tx half empty and tx empty. Hence, service the Tx interrupts before Bus not busy interrupt to update the i2c message status correctly. Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-05-14i2c: xiic: Fix coding style issuesMichal Simek1-17/+20
Most of these stuff are reported by checkpatch. But fixes are: - Incorrect indetation - Missing blank line after variable declaration - Additional () - Missing spaces around + - Missing parenthesis when if has them - Newlines - Remove MODULE_ALIAS - none is really using it Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-05-14i2c: xiic: return value of xiic_reinitShubhrajyoti Datta1-1/+4
Check the return value of xiic_reinit. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2022-03-02i2c: xiic: Make bus names uniqueRobert Hancock1-1/+2
This driver is for an FPGA logic core, so there can be arbitrarily many instances of the bus on a given system. Previously all of the I2C bus names were "xiic-i2c" which caused issues with lm_sensors when trying to map human-readable names to sensor inputs because it could not properly distinguish the busses, for example. Append the platform device name to the I2C bus name so it is unique between different instances. Fixes: e1d5b6598cdc ("i2c: Add support for Xilinx XPS IIC Bus Interface") Signed-off-by: Robert Hancock <robert.hancock@calian.com> Tested-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-09-14i2c: xiic: Fix RX IRQ busy checkMarek Vasut1-1/+1
In case the XIIC does TX/RX transfer, make sure no other kernel thread can start another TX transfer at the same time. This could happen since the driver only checks tx_msg for being non-NULL and returns -EBUSY in that case, however it is necessary to check also rx_msg for the same. Signed-off-by: Marek Vasut <marex@denx.de> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-09-14i2c: xiic: Only ever transfer single messageMarek Vasut1-34/+10
Transferring multiple messages via XIIC suffers from strange interaction between the interrupt status/enable register flags. These flags are being reused in the hardware to indicate different things for read and write transfer, and doing multiple transactions becomes horribly complex. Just send a single transaction and reload the controller with another message once the transaction is done in the interrupt handler thread. Signed-off-by: Marek Vasut <marex@denx.de> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-09-14i2c: xiic: Switch from waitqueue to completionMarek Vasut1-15/+18
There will never be threads queueing up in the xiic_xmit(), use completion synchronization primitive to wait for the interrupt handler thread to complete instead as it is much better fit and there is no need to overload it for this purpose. Signed-off-by: Marek Vasut <marex@denx.de> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-09-14i2c: xiic: Defer xiic_wakeup() and __xiic_start_xfer() in xiic_process()Marek Vasut1-11/+26
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>
2021-09-14i2c: xiic: Drop broken interrupt handlerMarek Vasut1-24/+1
The interrupt handler is missing locking when reading out registers and is racing with other threads which might access the driver. Drop it altogether, so that the threaded interrupt is always executed, as that one is already serialized by the driver mutex. This also allows dropping local_irq_save()/local_irq_restore() in xiic_start_recv(). Signed-off-by: Marek Vasut <marex@denx.de> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-09-14i2c: xiic: Fix broken locking on tx_msgMarek Vasut1-10/+16
The tx_msg is set from multiple places, sometimes without locking, which fall apart on any SMP system. Only ever access tx_msg inside the driver mutex. Signed-off-by: Marek Vasut <marex@denx.de> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-06-23i2c: xiic: Simplify with dev_err_probe()Krzysztof Kozlowski1-5/+4
Common pattern of handling deferred probe can be simplified with dev_err_probe(). Less code and the error value gets printed. Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2021-04-14i2c: xiic: fix reference leak when pm_runtime_get_sync failsQinglang Miao1-2/+2
The PM reference count is not expected to be incremented on return in xiic_xfer and xiic_i2c_remove. However, pm_runtime_get_sync will increment the PM reference count even failed. Forgetting to putting operation will result in a reference leak here. Replace it with pm_runtime_resume_and_get to keep usage counter balanced. Fixes: 10b17004a74c ("i2c: xiic: Fix the clocking across bind unbind") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-08-28i2c: xiic: Support forcing single-master in DTJaakko Laine1-0/+14
I2C master operating in multimaster mode can get stuck indefinitely if I2C start is detected on bus, but no master has a transaction going. This is a weakness in I2C standard, which defines no way to recover, since all masters are indefinitely disallowed from interrupting the currently operating master. A start condition can be created for example by an electromagnetic discharge applied near physical I2C lines. Or a already operating master could get reset immediately after sending a start. If it is known during device tree creation that only a single I2C master will be present on the bus, this deadlock of the I2C bus could be avoided in the driver by ignoring the bus_is_busy register of the xiic, since bus can never be reserved by any other master. This patch adds this support for detecting single-master flag in device tree and when provided, improves I2C reliability by ignoring the therefore unnecessary xiic bus_is_busy register. Error can be reproduced by pulling I2C SDA -line temporarily low by shorting it to ground, while linux I2C master is operating on it using the xiic driver. The application using the bus will start receiving linux error code 16: "Device or resource busy" indefinitely: kernel: pca953x 0-0020: failed writing register app: Error writing file, error: 16 With multi-master disabled device will instead receive error code 5: "I/O error" while SDA is grounded, but recover normal operation once short is removed. kernel: pca953x 0-0020: failed reading register app: Error reading file, error: 5 Signed-off-by: Jaakko Laine <ext-jaakko.laine@vaisala.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-08-28i2c: xiic: Improve struct memory alignmentJaakko Laine1-2/+2
xiic_i2c struct alignment causes the struct to take more space in memory than strictly required. Move state -member to end of struct to get less padding. Signed-off-by: Jaakko Laine <ext-jaakko.laine@vaisala.com> Suggested-by: Michal Simek <michal.simek@xilinx.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-08-28i2c: xiic: Change code alignment to 1 space onlyJaakko Laine1-24/+24
Alignment removed and replaced with 1 space only to reduce need for future alignment changes affecting multiple lines, when new variables are added. Signed-off-by: Jaakko Laine <ext-jaakko.laine@vaisala.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-01-29i2c: xiic: fix indentation issueColin Ian King1-1/+1
There is a statement that is indented one level too deeply, remove the extraneous tab. Fixes: b4c119dbc300 ("i2c: xiic: Add timeout to the rx fifo wait loop") Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: Shubhrajyoti Datta <shubhrajyoti.datta@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-15i2c: xiic: Fix the clocking across bind unbindShubhrajyoti Datta1-5/+7
The recommendation is that the set_active should be done with pm runtime disabled. Also fix the remove path for clocking. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-15i2c: xiic: defer the probe if clock is not foundVenkatesh Yadav Abbarapu1-1/+2
It's not always the case that clock is already available when i2c driver get probed at the first time, e.g. the clock is provided by clock wizard which may be probed after i2c driver. So let's defer the probe when devm_clk_get() call fails and give it chance to try later. Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-15i2c: xiic: Add timeout to the rx fifo wait loopShubhrajyoti Datta1-10/+42
Add timeout to the rx fifo empty wait loop. Also check for the return value for xiic_reinit and pass it to xiic_start_xfer. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-01-15i2c: xiic: convert to use i2c_new_client_device()Wolfram Sang1-1/+1
Move away from the deprecated API and return the shiny new ERRPTR where useful. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-11-11i2c: xiic: Fix kerneldoc warningsShubhrajyoti Datta1-0/+2
Fix the below warning by adding the description of clock and dev. drivers/i2c/busses/i2c-xiic.c:57: info: Scanning doc for struct xiic_i2c drivers/i2c/busses/i2c-xiic.c:84: warning: Function parameter or member 'dev' not described in 'xiic_i2c' drivers/i2c/busses/i2c-xiic.c:84: warning: Function parameter or member 'clk' not described in 'xiic_i2c' Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-06-08i2c: xiic: Add max_read_len quirkRobert Hancock1-0/+5
This driver does not support reading more than 255 bytes at once because the register for storing the number of bytes to read is only 8 bits. Add a max_read_len quirk to enforce this. This was found when using this driver with the SFP driver, which was previously reading all 256 bytes in the SFP EEPROM in one transaction. This caused a bunch of hard-to-debug errors in the xiic driver since the driver/logic was treating the number of bytes to read as zero. Rejecting transactions that aren't supported at least allows the problem to be diagnosed more easily. Signed-off-by: Robert Hancock <hancock@sedsystems.ca> Reviewed-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174Thomas Gleixner1-10/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 655 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-06i2c: xiic: Make the start and the byte count write atomicShubhrajyoti Datta1-0/+4
Disable interrupts while configuring the transfer and enable them back. We have below as the programming sequence 1. start and slave address 2. byte count and stop In some customer platform there was a lot of interrupts between 1 and 2 and after slave address (around 7 clock cyles) if 2 is not executed then the transaction is nacked. To fix this case make the 2 writes atomic. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> [wsa: added a newline for better readability] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2018-05-29i2c: busses: make use of i2c_8bit_addr_from_msgPeter Rosin1-9/+2
Because it looks neater. For diolan, this allows factoring out some code that is now common between if and else. For eg20t, pch_i2c_writebytes is always called with a write in msgs->flags, and pch_i2c_readbytes with a read. For imx, i2c_imx_dma_write and i2c_imx_write are always called with a write in msgs->flags, and i2c_imx_read with a read. For qup, qup_i2c_write_tx_fifo_v1 is always called with a write in qup->msg->flags. For stu300, also restructure debug output for resends, since that code as a result is only handling debug output. Reviewed-by: Guenter Roeck <linux@roeck-us.net> [diolan] Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> [efm32 and imx] Acked-by: Linus Walleij <linus.walleij@linaro.org> [stu300] Signed-off-by: Peter Rosin <peda@axentia.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-17Merge branch 'i2c/platform_data-immutable' into i2c/for-4.18Wolfram Sang1-1/+1
2018-05-17i2c: xiic: move header to platform_dataWolfram Sang1-1/+1
This header only contains platform_data. Move it to the proper directory. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Acked-by: Lee Jones <lee.jones@linaro.org>
2018-05-17i2c: xiic: fix spelling mistake: "unexpexted" -> "unexpected"Colin Ian King1-2/+2
Trivial fix to spelling mistakes in dev_dbg messages Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-17i2c: xiic: Make suspend function names consistentMoritz Fischer1-4/+4
Suspend functions seem to have been copied from i2c-cadence driver. Rename the functions to match the rest of the driver. Signed-off-by: Moritz Fischer <mdf@kernel.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-08-29i2c: busses: make i2c_adapter constBhumika Goyal1-1/+1
Make these const as they are only used in a copy operation. Done using Coccinelle. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Acked-by: David Daney <david.daney@cavium.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-07-31i2c: use dev_get_drvdata() to get private data in suspend/resume hooksMasahiro Yamada1-4/+2
Several drivers call to_platform_device() to get platform_device and pass it to platform_get_drvdata(). In platform_get_drvdata(), the platform_device is converted back to struct device again. Use dev_get_drvdata() to avoid platform_device/device dance. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> (for DesignWare only) Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-22i2c: don't print error when adding adapter failsWolfram Sang1-1/+0
The core will do this for us now. Signed-off-by: Wolfram Sang <wsa-dev@sang-engineering.com> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Acked-by: Peter Korsgaard <peter@korsgaard.com> Acked-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Neil Horman <nhorman@tuxdriver.com> Acked-by: Thierry Reding <treding@nvidia.com> Acked-by: Ray Jui <ray.jui@broadcom.com> Acked-by: Vladimir Zapolskiy <vz@mleia.com> Acked-by: Ludovic Desroches <ludovic.desroches@atmel.com> Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-03-03i2c: xiic: Implement power managementShubhrajyoti Datta1-7/+81
Enable power management. This patch enables the clocks before transfer and disables after the transfer. It also adds the clock description. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-30i2c: xiic: Replace spinlock with mutexLars-Peter Clausen1-6/+6
All protected sections are only called from sleep-able context, so there is no need to use a spinlock. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-20i2c: xiic: Prevent concurrent running of the IRQ handler and __xiic_start_xfer()Lars-Peter Clausen1-2/+1
Prior to commit e6c9a037bc8a ("i2c: xiic: Remove the disabling of interrupts") IRQs where disabled when the initial __xiic_start_xfer() was called. After the commit the interrupt is enabled while the function is running, this means it is possible for the interrupt to be triggered while the function is still running. When this happens the internal data structures get corrupted and undefined behavior can occur like the following crash: Internal error: Oops: 17 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 2040 Comm: i2cdetect Not tainted 4.0.0-02856-g047a308 #10956 Hardware name: Xilinx Zynq Platform task: ee0c9500 ti: e99a2000 task.ti: e99a2000 PC is at __xiic_start_xfer+0x6c4/0x7c8 LR is at __xiic_start_xfer+0x690/0x7c8 pc : [<c02bbffc>] lr : [<c02bbfc8>] psr: 800f0013 sp : e99a3da8 ip : 00000000 fp : 00000000 r10: 00000001 r9 : 600f0013 r8 : f0180000 r7 : f0180000 r6 : c064e444 r5 : 00000017 r4 : ee031010 r3 : 00000000 r2 : 00000000 r1 : 600f0013 r0 : 0000000f Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user Control: 18c5387d Table: 29a5404a DAC: 00000015 Process i2cdetect (pid: 2040, stack limit = 0xe99a2210) Stack: (0xe99a3da8 to 0xe99a4000) 3da0: ee031010 00000000 00000001 ee031020 ee031224 c02bc5ec 3dc0: ee34c604 00000000 ee0c9500 e99a3dcc e99a3dd0 e99a3dd0 e99a3dd8 c069f0e8 3de0: 00000000 ee031020 c064e100 ffff90bb e99a3e48 c02b6590 ee031020 00000001 3e00: e99a3e48 ee031020 00000000 e99a3e63 00000001 c02b6ec4 00000000 00000000 3e20: 00000000 c02b7320 e99a3ef0 00000000 00000000 e99e3df0 00000000 00000000 3e40: 00000103 2814575f 0000003e c00a0000 e99a3e85 0001003e ee0c0000 e99a3e63 3e60: eefd3578 c064e61c ee0c9500 c0041e04 0000056c e9a56db8 00006e5a b6f5c000 3e80: ee0c9548 eefd0040 00000001 eefd3540 ee0c9500 eefd39a0 c064b540 ee0c9500 3ea0: 00000000 ee92b000 00000000 bef4862c ee34c600 e99ecdc0 00000720 00000003 3ec0: e99a2000 00000000 00000000 c02b8b30 00000000 00000000 00000000 e99a3f24 3ee0: b6e80000 00000000 00000000 c04257e8 00000000 e99a3f24 c02b8f08 00000703 3f00: 00000003 c02116bc ee935300 00000000 bef4862c ee34c600 e99ecdc0 c02b91f0 3f20: e99ecdc0 00000720 bef4862c eeb725f8 e99ecdc0 c00c9e2c 00000003 00000003 3f40: ee248dc0 00000000 ee248dc8 00000002 eeb7c1a8 00000000 00000000 c00bb360 3f60: 00000000 00000000 00000003 ee248dc0 bef4862c e99ecdc0 e99ecdc0 00000720 3f80: 00000003 e99a2000 00000000 c00c9f68 00000000 00000000 b6f22000 00000036 3fa0: c000dfa4 c000de20 00000000 00000000 00000003 00000720 bef4862c bef4862c 3fc0: 00000000 00000000 b6f22000 00000036 00000000 00000000 b6f60000 00000000 3fe0: 00013040 bef48614 00008cab b6ecdbe6 400f0030 00000003 2f7fd821 2f7fdc21 [<c02bbffc>] (__xiic_start_xfer) from [<c02bc5ec>] (xiic_xfer+0x94/0x168) [<c02bc5ec>] (xiic_xfer) from [<c02b6590>] (__i2c_transfer+0x4c/0x7c) [<c02b6590>] (__i2c_transfer) from [<c02b6ec4>] (i2c_transfer+0x9c/0xc4) [<c02b6ec4>] (i2c_transfer) from [<c02b7320>] (i2c_smbus_xfer+0x3a0/0x4ec) [<c02b7320>] (i2c_smbus_xfer) from [<c02b8b30>] (i2cdev_ioctl_smbus+0xb0/0x214) [<c02b8b30>] (i2cdev_ioctl_smbus) from [<c02b91f0>] (i2cdev_ioctl+0xa0/0x1d4) [<c02b91f0>] (i2cdev_ioctl) from [<c00c9e2c>] (do_vfs_ioctl+0x4b0/0x5b8) [<c00c9e2c>] (do_vfs_ioctl) from [<c00c9f68>] (SyS_ioctl+0x34/0x5c) [<c00c9f68>] (SyS_ioctl) from [<c000de20>] (ret_fast_syscall+0x0/0x34) Code: e283300c e5843210 eafffe64 e5943210 (e1d320b4) The issue can easily be reproduced by performing I2C access under high system load or IO load. To fix the issue protect the invocation to __xiic_start_xfer() form xiic_start_xfer() with the same lock that is used to protect the interrupt handler. Fixes: e6c9a037bc8a ("i2c: xiic: Remove the disabling of interrupts") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Reviewed-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-11-20i2c: Revert "i2c: xiic: Do not reset controller before every transfer"Lars-Peter Clausen1-0/+3
Commit d701667bb331 ("i2c: xiic: Do not reset controller before every transfer") removed the reinitialization of the controller before the start of each transfer. Apparently this change is not safe to make and the commit results in random I2C bus failures. An easy way to trigger the issue is to run i2cdetect. Without the patch applied: 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- UU UU -- UU 3c -- -- UU 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- With the patch applied every other or so invocation: 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 10: 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 20: 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 30: -- -- -- -- -- -- -- -- UU UU -- UU 3c -- -- UU 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- So revert the commit for now. Fixes: d701667bb331 ("i2c: xiic: Do not reset controller before every transfer") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: xiic: Do not continue in case of errors in RxShubhrajyoti Datta1-0/+2
In case of error conditions like Arbitration lost or NACK lets signal the waiting process. Handle error cases in the Rx path Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: xiic: Service all interrupts in isrShubhrajyoti Datta1-14/+10
Currently only one interrupt is serviced in the isr. In case the multiple interrupts happen simultenously we service and ack only one of them. Check for all the causes in the isr and service them. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: xiic: Remove the Addressed as slave interruptShubhrajyoti Datta1-1/+1
Currently there is no slave mode support in the driver also in the isr we just ack it and do nothing. So disable the AAS interrupt. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: xiic: Remove busy loop while waiting for bus busyShubhrajyoti Datta1-1/+1
Remove the busy loop while waiting for bus busy. Instead let the processor sleep. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: xiic: Remove the disabling of interruptsShubhrajyoti Datta1-7/+0
Currently before every transfer the interrupts are disabled. So incase the slave nacks in the middle of the transfer the current transfer is not aborted. Upon enabling the interrupts conditions like NACK , arbitration lost will not be masked. Remove the disabling of the interrupts. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: xiic: Do not reset controller before every transferShubhrajyoti Datta1-1/+0
Currently before every transfer the controller is reinitialised. We are already resetting the controller upon errors so upon every transfer is a performance kill. Remove the same. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: xiic: move the xiic_process to thread contextShubhrajyoti Datta1-13/+20
The xiic_process is a 154 line code that runs in isr context currently move it to thread context. Also the name xiic_process suggests that the intension was to run in process context. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> [wsa: initialized irqreturn_t to IRQ_NONE instead of IRQ_HANDLED] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-08-10i2c: xiic: Remove the disabling of interruptsShubhrajyoti Datta1-3/+0
Currently the interrupts are disabled at the start of the isr and enabled at the end of the isr. Remove the same. In case the slave device NACKs the transaction while in the isr the transfer will continue and the NACK interrupt will arrive only after the isr is serviced. Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-05-12i2c: xiic: Fix kerneldoc warningsShubhrajyoti Datta1-0/+1
info(drivers/i2c/busses/i2c-xiic.c:55): Scanning doc for struct xiic_i2c Warning(drivers/i2c/busses/i2c-xiic.c:79): No description found for parameter 'endianness' Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-12-14Merge tag 'driver-core-3.19-rc1' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core update from Greg KH: "Here's the set of driver core patches for 3.19-rc1. They are dominated by the removal of the .owner field in platform drivers. They touch a lot of files, but they are "simple" changes, just removing a line in a structure. Other than that, a few minor driver core and debugfs changes. There are some ath9k patches coming in through this tree that have been acked by the wireless maintainers as they relied on the debugfs changes. Everything has been in linux-next for a while" * tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits) Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries" fs: debugfs: add forward declaration for struct device type firmware class: Deletion of an unnecessary check before the function call "vunmap" firmware loader: fix hung task warning dump devcoredump: provide a one-way disable function device: Add dev_<level>_once variants ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries ath: use seq_file api for ath9k debugfs files debugfs: add helper function to create device related seq_file drivers/base: cacheinfo: remove noisy error boot message Revert "core: platform: add warning if driver has no owner" drivers: base: support cpu cache information interface to userspace via sysfs drivers: base: add cpu_device_create to support per-cpu devices topology: replace custom attribute macros with standard DEVICE_ATTR* cpumask: factor out show_cpumap into separate helper function driver core: Fix unbalanced device reference in drivers_probe driver core: fix race with userland in device_add() sysfs/kernfs: make read requests on pre-alloc files use the buffer. sysfs/kernfs: allow attributes to request write buffer be pre-allocated. fs: sysfs: return EGBIG on write if offset is larger than file size ...
2014-11-17i2c: xiic: Fix big-endian register accessThomas Gessler1-5/+53
The driver tried to access device registers with the (little-endian) iowrite/ioread functions. While this worked on little-endian machines (e.g. Microblaze with AXI bus), it made the driver unusable on big-endian machines (e.g. PPC405 with PLB). During the probe function, the driver tried to write a 32-bit reset mask into the reset register. This caused an error interrupt on big-endian systems, because the device detected an invalid (byte-swapped) reset mask. The result was an Oops. The patch implements an endianness detection similar to the one used in other Xilinx drivers like drivers/spi/spi-xilinx.c. It was tested on a PPC405/PLB system. Signed-off-by: Thomas Gessler <Thomas.Gessler@exp2.physik.uni-giessen.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-07i2c: remove FSF addressWolfram Sang1-4/+0
We have a central copy of the GPL for that. Some addresses were already outdated. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2014-10-20i2c: busses: drop owner assignment from platform_driversWolfram Sang1-1/+0
A platform_driver does not need to set an owner, it will be populated by the driver core. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>