summaryrefslogtreecommitdiffstats
path: root/drivers/i2c
AgeCommit message (Collapse)AuthorFilesLines
2019-03-13i2c: i2c-designware-platdrv: Always use a dynamic adapter numberHans de Goede1-4/+1
Before this commit the i2c-designware-platdrv assumes that if the pdev has an apci-companion it should use a dynamic adapter-nr and it sets adapter->nr to -1, otherwise it will use pdev->id as adapter->nr. There are 3 ways how platform_device-s to which i2c-designware-platdrv will bind can be instantiated: 1) Through of / devicetree 2) Through ACPI enumeration 3) Explicitly instantiated through platform_device_create + add 1) In case of devicetree-instantiation the drivers/of code always sets pdev->id to PLATFORM_DEVID_NONE, which is -1 so in this case both paths to set adapter->nr end up doing the same thing. 2) In case of ACPI instantiation the device will always have an ACPI-companion, so we are already using dynamic adapter-nrs. 3) There are 2 places manually instantiating a designware_i2c platform_dev: drivers/mfd/intel_quark_i2c_gpio.c drivers/mfd/intel-lpss.c In the intel_quark_i2c_gpio.c case pdev->id is always 0, so switching to dynamic adapter-nrs here could lead to the bus-number no longer being stable, but the quark X1000 only has 1 i2c-controller, which will also be assigned bus-number 0 when using dynamic adapter-nrs. In the intel-lpss.c case intel_lpss_probe() is called from either intel-lpss-acpi.c in which case there always is an ACPI-companion, or from intel-lpss-pci.c. In most cases devices handled by intel-lpss-pci.c also have an ACPI-companion, so we use a dynamic adapter-nr. But in some cases the ACPI-companion is missing and we would use pdev->id (allocated from intel_lpss_devid_ida). Devices which use the intel-lpss-pci.c code typically have many i2c busses, so using pdev->id in this case may lead to a bus-number conflict, triggering a WARN(id < 0, "couldn't get idr") in i2c-core-base.c causing an oops an the adapter registration to fail. So in this case using non dynamic adapter-nrs is actually undesirable. One machine on which this oops was triggering is the Apollo Lake based Acer TravelMate Spin B118. TL;DR: Switching to always using dynamic adapter-numbers does not make any difference in most cases and in the one case where it does make a difference the behavior change is desirable because the old behavior caused an oops. BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1687065 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-13i2c: i2c-designware-platdrv: Cleanup setting of the adapter numberHans de Goede1-4/+6
i2c-designware-platdrv assumes that if the pdev has an apci-companion it should use a dynamic adapter-nr and otherwise it will use pdev->id as adapter-nr. Before this commit the setting of the adapter.nr was somewhat convoluted, in the acpi_companion case it was set from dw_i2c_acpi_configure, in the non acpi_companion case it was set from dw_i2c_set_fifo_size based on tx_fifo_depth not being set yet indicating that dw_i2c_acpi_configure was not executed. This cleans this up, directly setting the adapter-nr from dw_i2c_plat_probe for both cases. Signed-off-by: Hans de Goede <hdegoede@redhat.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@the-dreams.de>
2019-03-13i2c: add extra check to safe DMA buffer helperWolfram Sang1-2/+7
Make sure we report 'no buffer' for 0-length messages. This can only happen if threshold is set to 0 which is kind of bogus but we should still handle this situation. Update the docs and add a debug message to educate callers of this function. Reported-by: Hsin-Yi Wang <hsinyi@chromium.org> Fixes: e94bc5d18be0 ("i2c: add helpers to ease DMA handling") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Hsin-Yi Wang <hsinyi@chromium.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-12i2c: i2c-stm32f7: Fix SDADEL minimum formulaNicolas Le Bayon1-1/+1
It conforms with Reference Manual I2C timing section. Fixes: aeb068c57214 ("i2c: i2c-stm32f7: add driver") Signed-off-by: Nicolas Le Bayon <nicolas.le.bayon@st.com> Signed-off-by: Bich Hemon <bich.hemon@st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-12i2c: rcar: explain the lockless designWolfram Sang1-0/+9
To make sure people can understand the lockless design of this driver without the need to dive into git history, add a comment giving an overview of the situation. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-12i2c: rcar: fix concurrency issue related to ICDMAERHiromitsu Yamasaki1-3/+3
This patch fixes the problem that an interrupt may set up a new I2C message and the DMA callback overwrites this setup. By disabling the DMA Enable Register(ICDMAER), rcar_i2c_dma_unmap() enables interrupts for register settings (such as Master Control Register(ICMCR)) and advances the I2C transfer sequence. If an interrupt occurs immediately after ICDMAER is disabled, the callback handler later continues and overwrites the previous settings from the interrupt. So, disable ICDMAER at the end of the callback to ensure other interrupts are masked until then. Note that this driver needs to work lock-free because there are IP cores with a HW race condition which prevent us from using a spinlock in the interrupt handler. Reproduction test: 1. Add a delay after disabling ICDMAER. (It is expected to generate an interrupt of rcar_i2c_irq()) void rcar_i2c_dma_unmap(struct rcar_i2c_priv *priv) { ... rcar_i2c_write(priv, ICDMAER, 0); usleep_range(500, 800) ... priv->dma_direction = DMA_NONE; } 2. Execute DMA transfers $ i2ctransfer -y 4 w9@0x6a 1 1+ r16 3. A log message of BUG_ON() will be displayed. Fixes: 73e8b0528346 ("i2c: rcar: add DMA support") Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> [wsa: updated test case to be more reliable, added note to comment] Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-12i2c: sis630: correct format stringsLouis Taylor1-2/+2
When compiling with -Wformat, clang warns: drivers/i2c/busses/i2c-sis630.c:482:4: warning: format specifies type 'unsigned short' but the argument has type 'int' [-Wformat] smbus_base + SMB_STS, ^~~~~~~~~~~~~~~~~~~~ drivers/i2c/busses/i2c-sis630.c:483:4: warning: format specifies type 'unsigned short' but the argument has type 'int' [-Wformat] smbus_base + SMB_STS + SIS630_SMB_IOREGION - 1); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/i2c/busses/i2c-sis630.c:531:37: warning: format specifies type 'unsigned short' but the argument has type 'int' [-Wformat] "SMBus SIS630 adapter at %04hx", smbus_base + SMB_STS); ~~~~~ ^~~~~~~~~~~~~~~~~~~~ This patch fixes the format strings to use the format type for int. Link: https://github.com/ClangBuiltLinux/linux/issues/378 Signed-off-by: Louis Taylor <louis@kragniz.eu> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-12i2c: mediatek: modify threshold passed to i2c_get_dma_safe_msg_buf()Hsin-Yi Wang1-4/+4
DMA with zero-length transfers doesn't make sense and this HW doesn't support them at all, so increase the threshold. Fixes: fc66b39fe36a ("i2c: mediatek: Use DMA safe buffers for i2c transactions") Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> [wsa: reworded commit message] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-09Merge tag 'pci-v5.1-changes' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - Use match_string() instead of reimplementing it (Andy Shevchenko) - Enable SERR# forwarding for all bridges (Bharat Kumar Gogada) - Use Latency Tolerance Reporting if already enabled by platform (Bjorn Helgaas) - Save/restore LTR info for suspend/resume (Bjorn Helgaas) - Fix DPC use of uninitialized data (Dongdong Liu) - Probe bridge window attributes only once at enumeration-time to fix device accesses during rescan (Bjorn Helgaas) - Return BAR size (not "size -1 ") from pci_size() to simplify code (Du Changbin) - Use config header type (not class code) identify bridges more reliably (Honghui Zhang) - Work around Intel Denverton incorrect Trace Hub BAR size reporting (Alexander Shishkin) - Reorder pciehp cached state/hardware state updates to avoid missed interrupts (Mika Westerberg) - Turn ibmphp semaphores into completions or mutexes (Arnd Bergmann) - Mark expected switch fall-through (Mathieu Malaterre) - Use of_node_name_eq() for node name comparisons (Rob Herring) - Add ACS and pciehp quirks for HXT SD4800 (Shunyong Yang) - Consolidate Rohm Vendor ID definitions (Andy Shevchenko) - Use u32 (not __u32) for things not exposed to userspace (Logan Gunthorpe) - Fix locking semantics of bus and slot reset interfaces (Alex Williamson) - Update PCIEPORTBUS Kconfig help text (Hou Zhiqiang) - Allow portdrv to claim subtractive decode Ports so PCIe services will work for them (Honghui Zhang) - Report PCIe links that become degraded at run-time (Alexandru Gagniuc) - Blacklist Gigabyte X299 Root Port power management to fix Thunderbolt hotplug (Mika Westerberg) - Revert runtime PM suspend/resume callbacks that broke PME on network cable plug (Mika Westerberg) - Disable Data Link State Changed interrupts to prevent wakeup immediately after suspend (Mika Westerberg) - Extend altera to support Stratix 10 (Ley Foon Tan) - Allow building altera driver on ARM64 (Ley Foon Tan) - Replace Douglas with Tom Joseph as Cadence PCI host/endpoint maintainer (Lorenzo Pieralisi) - Add DT support for R-Car RZ/G2E (R8A774C0) (Fabrizio Castro) - Add dra72x/dra74x/dra76x SoC compatible strings (Kishon Vijay Abraham I) - Enable x2 mode support for dra72x/dra74x/dra76x SoC (Kishon Vijay Abraham I) - Configure dra7xx PHY to PCIe mode (Kishon Vijay Abraham I) - Simplify dwc (remove unnecessary header includes, name variables consistently, reduce inverted logic, etc) (Gustavo Pimentel) - Add i.MX8MQ support (Andrey Smirnov) - Add message to help debug dwc MSI-X mask bit errors (Gustavo Pimentel) - Work around imx7d PCIe PLL erratum (Trent Piepho) - Don't assert qcom reset GPIO during probe (Bjorn Andersson) - Skip dwc MSI init if MSIs have been disabled (Lucas Stach) - Use memcpy_fromio()/memcpy_toio() instead of plain memcpy() in PCI endpoint framework (Wen Yang) - Add interface to discover supported endpoint features to replace a bitfield that wasn't flexible enough (Kishon Vijay Abraham I) - Implement the new supported-feature interface for designware-plat, dra7xx, rockchip, cadence (Kishon Vijay Abraham I) - Fix issues with 64-bit BAR in endpoints (Kishon Vijay Abraham I) - Add layerscape endpoint mode support (Xiaowei Bao) - Remove duplicate struct hv_vp_set in favor of struct hv_vpset (Maya Nakamura) - Rework hv_irq_unmask() to use cpumask_to_vpset() instead of open-coded reimplementation (Maya Nakamura) - Align Hyper-V struct retarget_msi_interrupt arguments (Maya Nakamura) - Fix mediatek MMIO size computation to enable full size of available MMIO space (Honghui Zhang) - Fix mediatek DMA window size computation to allow endpoint DMA access to full DRAM address range (Honghui Zhang) - Fix mvebu prefetchable BAR regression caused by common bridge emulation that assumed all bridges had prefetchable windows (Thomas Petazzoni) - Make advk_pci_bridge_emul_ops static (Wei Yongjun) - Configure MPS settings for VMD root ports (Jon Derrick) * tag 'pci-v5.1-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (92 commits) PCI: Update PCIEPORTBUS Kconfig help text PCI: Fix "try" semantics of bus and slot reset PCI/LINK: Report degraded links via link bandwidth notification dt-bindings: PCI: altera: Add altr,pcie-root-port-2.0 PCI: altera: Enable driver on ARM64 PCI: altera: Add Stratix 10 PCIe support PCI/PME: Fix possible use-after-free on remove PCI: aardvark: Make symbol 'advk_pci_bridge_emul_ops' static PCI: dwc: skip MSI init if MSIs have been explicitly disabled PCI: hv: Refactor hv_irq_unmask() to use cpumask_to_vpset() PCI: hv: Replace hv_vp_set with hv_vpset PCI: hv: Add __aligned(8) to struct retarget_msi_interrupt PCI: mediatek: Enlarge PCIe2AHB window size to support 4GB DRAM PCI: mediatek: Fix memory mapped IO range size computation PCI: dwc: Remove superfluous shifting in definitions PCI: dwc: Make use of GENMASK/FIELD_PREP PCI: dwc: Make use of BIT() in constant definitions PCI: dwc: Share code for dw_pcie_rd/wr_other_conf() PCI: dwc: Make use of IS_ALIGNED() PCI: imx6: Add code to request/control "pcie_aux" clock for i.MX8MQ ...
2019-03-08Merge branch 'i2c/for-5.1' of ↵Linus Torvalds25-431/+1324
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: - the I2C core gained helpers to assist drivers in handling their suspended state, and drivers were converted to use it - two new fault-injectors for stress-testing - bigger refactoring and feature improvements for the ocores, sh_mobile, and tegra drivers - platform_data removal for the at24 EEPROM driver - ... and various improvements and bugfixes all over the subsystem * 'i2c/for-5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (69 commits) i2c: Allow recovery of the initial IRQ by an I2C client device. i2c: ocores: turn incomplete kdoc into a comment i2c: designware: Do not allow i2c_dw_xfer() calls while suspended i2c: tegra: Only display error messages if DMA setup fails i2c: gpio: fault-injector: add 'inject_panic' injector i2c: gpio: fault-injector: add 'lose_arbitration' injector i2c: tegra: remove multi-master support i2c: tegra: remove master fifo support on tegra186 i2c: tegra: change phrasing, "fallbacking" to "falling back" i2c: expand minor range when registering chrdev region i2c: aspeed: Add multi-master use case support i2c: core-smbus: don't trace smbus_reply data on errors i2c: ocores: Add support for bus clock via platform data i2c: ocores: Add support for IO mapper registers. i2c: ocores: checkpatch fixes i2c: ocores: add SPDX tag i2c: ocores: add polling interface i2c: ocores: do not handle IRQ if IF is not set i2c: ocores: stop transfer on timeout i2c: tegra: add i2c interface timing support ...
2019-02-24i2c: Allow recovery of the initial IRQ by an I2C client device.Jim Broadus1-4/+5
A previous change allowed I2C client devices to discover new IRQs upon reprobe by clearing the IRQ in i2c_device_remove. However, if an IRQ was assigned in i2c_new_device, that information is lost. For example, the touchscreen and trackpad devices on a Dell Inspiron laptop are I2C devices whose IRQs are defined by ACPI extended IRQ types. The client device structures are initialized during an ACPI walk. After removing the i2c_hid device, modprobe fails. This change caches the initial IRQ value in i2c_new_device and then resets the client device IRQ to the initial value in i2c_device_remove. Fixes: 6f108dd70d30 ("i2c: Clear client->irq in i2c_device_remove") Signed-off-by: Jim Broadus <jbroadus@gmail.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com> [wsa: this is an easy to backport fix for the regression. We will refactor the code to handle irq assignments better in general.] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-24i2c: ocores: turn incomplete kdoc into a commentWolfram Sang1-3/+3
gcc complains, rightfully so, I think: drivers/i2c/busses/i2c-ocores.c:32: warning: Cannot understand * @process_lock: protect I2C transfer process. on line 32 - I thought it was a doc line Make it a simple comment. Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: designware: Do not allow i2c_dw_xfer() calls while suspendedHans de Goede4-1/+17
On most Intel Bay- and Cherry-Trail systems the PMIC is connected over I2C and the PMIC is accessed through various means by the _PS0 and _PS3 ACPI methods (power on / off methods) of various devices. This leads to suspend/resume ordering problems where a device may be resumed and get its _PS0 method executed before the I2C controller is resumed. On Cherry Trail this leads to errors like these: i2c_designware 808622C1:06: controller timed out ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion] ACPI Error: Method parse/execution failed \_SB.P18W._ON, AE_ERROR video LNXVIDEO:00: Failed to change power state to D0 But on Bay Trail this caused I2C reads to seem to succeed, but they end up returning wrong data, which ends up getting written back by the typical read-modify-write cycle done to turn on various power-resources. Debugging the problems caused by this silent data corruption is quite nasty. This commit adds a check which disallows i2c_dw_xfer() calls to happen until the controller's resume method has completed. Which turns the silent data corruption into getting these errors in dmesg instead: i2c_designware 80860F41:04: Error i2c_dw_xfer call while suspended ACPI Error: AE_ERROR, Returned by Handler for [UserDefinedRegion] ACPI Error: Method parse/execution failed \_SB.PCI0.GFX0._PS0, AE_ERROR Which is much better. Note the above errors are an example of issues which this patch will help to debug, the actual fix requires fixing the suspend order and this has been fixed by a different commit. Note the setting / clearing of the suspended flag in the suspend / resume methods is NOT protected by i2c_lock_bus(). This is intentional as these methods get called from i2c_dw_xfer() (through pm_runtime_get/put) a nd i2c_dw_xfer() is called with the i2c_bus_lock held, so otherwise we would deadlock. This means that there is a theoretical race between a non runtime suspend and the suspended check in i2c_dw_xfer(), this is not a problem since normally we should not hit the race and this check is primarily a debugging tool so hitting the check if there are suspend/resume ordering problems does not need to be 100% reliable. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: tegra: Only display error messages if DMA setup failsJonathan Hunter1-4/+6
Commit 86c92b9965ff ("i2c: tegra: Add DMA support") added DMA support to the Tegra I2C driver for Tegra devices that support the APB DMA controller. One side-effect of this change is that even for Tegra devices that do not have an APB DMA controller and hence, cannot support DMA tranfers for I2C transactions, the following error messages are still displayed ... ERR KERN tegra-i2c 31c0000.i2c: cannot use DMA: -19 ERR KERN tegra-i2c 31c0000.i2c: falling back to PIO There is no point displaying the above messages for devices that do not have an APB DMA controller and so fix this by returning from the tegra_i2c_init_dma() function if 'has_apb_dma' is not true. Furthermore, if CONFIG_TEGRA20_APB_DMA is not set, then rather than printing an error message, print an debug message as for whatever reason this could be intentional. Fixes: 86c92b9965ff ("i2c: tegra: Add DMA support") Signed-off-by: Jonathan Hunter <jonathanh@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: gpio: fault-injector: add 'inject_panic' injectorWolfram Sang1-1/+30
Add a fault injector simulating a Kernel panic happening after starting a transfer. Read the docs for its usage. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: gpio: fault-injector: add 'lose_arbitration' injectorWolfram Sang1-0/+74
Add a fault injector simulating 'arbitration lost' from multi-master setups. Read the docs for its usage. A helper function for future fault injectors using SCL interrupts is created to achieve this. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: tegra: remove multi-master supportSowjanya Komatineni1-2/+2
Multi-master support is defeatured on Tegra210 and Tegra186 due to known bugs. This patch removes multi-master support for Tegra210 and Tegra186 I2C HW feature. Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: tegra: remove master fifo support on tegra186Sowjanya Komatineni1-1/+1
Tegra186 does not have master FIFO control register and instead uses FIFO control register like prior Tegra chipset. This patch fixes this and prevents crashing during boot when accessing FIFO control registers. Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-15i2c: tegra: change phrasing, "fallbacking" to "falling back"Colin Ian King1-2/+2
The phrasing in two dev_err messages is using fallbacking which os less understandable than "falling back", so fix this up. Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-15i2c: expand minor range when registering chrdev regionChengguang Xu1-1/+1
Actually, total amount of available minor number for a single major is MINORMASK + 1. So expand minor range when registering chrdev region. Signed-off-by: Chengguang Xu <cgxu519@gmx.com> [wsa: fixed typo in commit message] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-15i2c: aspeed: Add multi-master use case supportJae Hyun Yoo1-26/+93
In multi-master environment, this driver's master cannot know exactly when a peer master sends data to this driver's slave so cases can be happened that this master tries sending data through the master_xfer function but slave data from a peer master is still being processed or slave xfer is started by a peer immediately after it queues a master command. To support multi-master use cases properly, this H/W provides arbitration in physical level and it provides priority based command handling too to avoid conflicts in multi-master environment, means that if a master and a slave events happen at the same time, H/W will handle a higher priority event first and a pending event will be handled when bus comes back to the idle state. To support this H/W feature properly, this patch adds the 'pending' state of master and its handling code so that the pending master xfer can be continued after slave operation properly. Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> Reviewed-by: Brendan Higgins <brendanhiggins@google.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-15i2c: bcm2835: Clear current buffer pointers and counts after a transferPaul Kocialkowski1-0/+12
The driver's interrupt handler checks whether a message is currently being handled with the curr_msg pointer. When it is NULL, the interrupt is considered to be unexpected. Similarly, the i2c_start_transfer routine checks for the remaining number of messages to handle in num_msgs. However, these values are never cleared and always keep the message and number relevant to the latest transfer (which might be done already and the underlying message memory might have been freed). When an unexpected interrupt hits with the DONE bit set, the isr will then try to access the flags field of the curr_msg structure, leading to a fatal page fault. The msg_buf and msg_buf_remaining fields are also never cleared at the end of the transfer, which can lead to similar pitfalls. Fix these issues by introducing a cleanup function and always calling it after a transfer is finished. Fixes: e2474541032d ("i2c: bcm2835: Fix hang for writing messages larger than 16 bytes") Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com> Acked-by: Stefan Wahren <stefan.wahren@i2se.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-15i2c: cadence: Fix the hold bit settingShubhrajyoti Datta1-2/+7
In case the hold bit is not needed we are carrying the old values. Fix the same by resetting the bit when not needed. Fixes the sporadic i2c bus lockups on National Instruments Zynq-based devices. Fixes: df8eb5691c48 ("i2c: Add driver for Cadence I2C controller") Reported-by: Kyle Roeschley <kyle.roeschley@ni.com> Acked-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Tested-by: Kyle Roeschley <kyle.roeschley@ni.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: core-smbus: don't trace smbus_reply data on errorsJohn Sperbeck1-1/+1
If an smbus transfer fails, there's no guarantee that the output buffer was written. So, avoid trying to show the output buffer when tracing after an error. This was 'mostly harmless', but would trip up kasan checking if left-over cruft in byte 0 is a large length, causing us to read from unwritten memory. Signed-off-by: John Sperbeck <jsperbeck@google.com> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: ocores: Add support for bus clock via platform dataAndrew Lunn1-1/+4
Add the I2C bus clock speed to the platform data structure. If not set, default to 100KHz as before. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: ocores: Add support for IO mapper registers.Andrew Lunn1-3/+29
Some implementations of the OCORES i2c bus master use IO mapped registers. Add support for getting the IO registers from the platform data, and register accessor functions. Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: ocores: checkpatch fixesFederico Vaga1-11/+18
Miscellaneous style fixes from checkpatch Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: ocores: add SPDX tagFederico Vaga1-4/+1
It adds the SPDX tag and it removes the old text about the GPLv2. Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: ocores: add polling interfaceFederico Vaga1-21/+161
This driver assumes that an interrupt line is always available for the I2C master. This is not always the case and this patch adds support for a polling version. Report from Andrew Lunn: I did some timing tests for this. On my box, we request a udelay of 80uS. The kernel actually delays for about 79uS. We then spin in ocores_wait() for an additional 10-11uS, which is 3 to 4 iterations. There are actually 9 bits on the wire, not 8, since there is an ACK/NACK bit after the actual data transfer. So i changed the delay to (9 * 1000) / i2c->bus_clock_khz. That resulted in ocores_wait() mostly not looping at all. But for reading an 4K AT24 EEPROM, it increased the read time by 10ms, from 424ms to 434ms. So we should probably keep with 8. Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: ocores: do not handle IRQ if IF is not setFederico Vaga1-3/+6
If the Interrupt Flag (IF) is not set, we should not handle the IRQ: - the line can be shared with other devices - it can be a spurious interrupt To avoid reading twice the status register, the ocores_process() function expects it to be read by the caller. Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Acked-by: Peter Korsgaard <peter@korsgaard.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: ocores: stop transfer on timeoutFederico Vaga1-9/+45
Detecting a timeout is ok, but we also need to assert a STOP command on the bus in order to prevent it from generating interrupts when there are no on going transfers. Example: very long transmission. 1. ocores_xfer: START a transfer 2. ocores_isr : handle byte by byte the transfer 3. ocores_xfer: goes in timeout [[bugfix here]] 4. ocores_xfer: return to I2C subsystem and to the I2C driver 5. I2C driver : it may clean up the i2c_msg memory 6. ocores_isr : receives another interrupt (pending bytes to be transferred) but the i2c_msg memory is invalid now So, since the transfer was too long, we have to detect the timeout and STOP the transfer. Another point is that we have a critical region here. When handling the timeout condition we may have a running IRQ handler. For this reason I introduce a spinlock. In order to make easier to understan locking I have: - added a new function to handle timeout - modified the current ocores_process() function in order to be protected by the new spinlock Like this it is obvious at first sight that this locking serializes the execution of ocores_process() and ocores_process_timeout() Signed-off-by: Federico Vaga <federico.vaga@cern.ch> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: tegra: add i2c interface timing supportSowjanya Komatineni1-30/+159
This patch adds I2C interface timing registers support for proper bus rate configuration along with meeting the I2C spec setup and hold times based on the tuning performed on Tegra210, Tegra186 and Tegra194 platforms. I2C_INTERFACE_TIMING_0 register contains TLOW and THIGH field and Tegra I2C controller design uses them as a part of internal clock divisor. I2C_INTERFACE_TIMING_1 register contains the setup and hold times for start and stop conditions. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: tegra: update transfer timeoutSowjanya Komatineni1-4/+11
Tegra194 allows max of 64K bytes and Tegra186 and prior allows max of 4K bytes of transfer per packet. one sec timeout is not enough for transfers more than 10K bytes at STD bus rate. This patch updates I2C transfer timeout based on the transfer size and I2C bus rate to allow enough time during max transfer size at lower bus speed. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: tegra: Add DMA supportSowjanya Komatineni1-49/+383
This patch adds DMA support for Tegra I2C. Tegra I2C TX and RX FIFO depth is 8 words. PIO mode is used for transfer size of the max FIFO depth and DMA mode is used for transfer size higher than max FIFO depth to save CPU overhead. PIO mode needs full intervention of CPU to fill or empty FIFO's and also need to service multiple data requests interrupt for the same transaction. This adds delay between data bytes of the same transfer when CPU is fully loaded and some slave devices has internal timeout for no bus activity and stops transaction to avoid bus hang. DMA mode is helpful in such cases. DMA mode is also helpful for Large transfers during downloading or uploading FW over I2C to some external devices. Tegra210 and prior Tegra chips use APBDMA driver which is replaced with GPCDMA on Tegra186 and Tegra194. This patch uses has_apb_dma flag in hw_feature to differentiate DMA driver change between Tegra chipset. APBDMA driver is registered from module-init level and this patch also has a change to register I2C driver at module-init level rather than subsys-init to avoid deferring I2C probe till APBDMA driver is registered. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: tegra: update maximum transfer sizeSowjanya Komatineni1-2/+6
Tegra194 supports maximum 64K bytes per packet including 12 bytes of packet header irrespective of PIO or DMA mode transfer. This patch updates Tegra194 max write length to account for packet header size for transfers. Cc: stable@vger.kernel.org # 4.20+ Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: tegra: fix maximum transfer sizeSowjanya Komatineni1-1/+1
Tegra186 and prior supports maximum 4K bytes per packet transfer including 12 bytes of packet header. This patch fixes max write length limit to account packet header size for transfers. Cc: stable@vger.kernel.org # 4.4+ Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: tegra: add bus clear Master SupportSowjanya Komatineni1-0/+81
Bus clear feature of Tegra I2C controller helps to recover from bus hang when I2C master loses the bus arbitration due to the slave device holding SDA LOW continuously for some unknown reasons. Per I2C specification, the device that held the bus LOW should release it within 9 clock pulses. During bus clear operation, Tegra I2C controller sends 9 clock pulses and terminates the transaction with STOP condition. Upon successful bus clear operation, bus goes to idle state and driver retries the transaction. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14i2c: tegra: sort all the include headers alphabeticallySowjanya Komatineni1-11/+8
This patch sorts all the include headers alphabetically for the I2C Tegra driver. Acked-by: Thierry Reding <treding@nvidia.com> Reviewed-by: Dmitry Osipenko <digetx@gmail.com> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-14Merge branch 'i2c/for-current' into i2c/for-5.1Wolfram Sang3-9/+25
2019-02-08i2c: rcar: refactor TCYC handlingWolfram Sang1-9/+6
The latest documentation made it clear that we need to initialize the TCYC value independently of DMA. The old code used TCYC06 (wrongly) for non-DMA transfers. The new code sets TCYC up independently from DMA. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-08i2c: gpio: merge two very similar commentsWolfram Sang1-12/+5
I think it is clear enough if we have the explanation once and make it clear it is applicable for both SCL and SDA. Reword it a little with the help of Simon's native language skills :) Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-08i2c: sh_mobile: use new clock calculation formulas for Gen2Wolfram Sang1-5/+5
We measured the clock on a Lager and an Ebisu board. The new formula gives better results for both. So after Gen3, switch to this formula for all Gen2 SoCs. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-08i2c: sh_mobile: use new clock calculation formulas for Gen3Wolfram Sang1-3/+3
We could finally measure the clock on an Ebisu board. The new formula gives way better results, i.e. 100kHz instead of 106kHz and 400kHz instead of 387kHz. Switch to these formulas for all Gen3 SoCs. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-08i2c: sh_mobile: sort compatible entriesWolfram Sang1-2/+2
Makes it easier to add new ones. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-08i2c: cbus-gpio: Switch to use GPIO descriptorsLinus Walleij1-50/+30
This augments the CBUS GPIO I2C driver to use GPIO descriptors for clock, sel and data. We drop the platform data that was only used for carrying GPIO numbers and use machine descriptor tables instead. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi> Acked-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05i2c: rcar: comment maintenanceWolfram Sang1-5/+2
Update copyright years and remove a comment which grew incorrect and useless over time. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05i2c: gpio: fault-injector: sort debugfs files alphabeticallyWolfram Sang1-2/+2
There is no value in chronological sorting. Make it easier to follow for humans. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05i2c: mediatek: remove completion_done()qii wang1-2/+0
Completion_done() is useless when we don't use its return value, so we remove it. Signed-off-by: qii wang <qii.wang@mediatek.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05i2c: mediatek: speeds is replaced by macros definitionsqii wang1-2/+2
Different speeds have been defined by macros, so we use macros definitions. Signed-off-by: qii wang <qii.wang@mediatek.com> Reviewed-by: Nicolas Boichat <drinkcat@chromium.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-05i2c: gpio: sort includesWolfram Sang1-5/+5
Less risk for duplications when adding new ones. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>