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2019-08-06i2c: designware: Fix unused variable warningShaokun Zhang1-1/+0
drivers/i2c/busses/i2c-designware-master.c: In function ‘i2c_dw_init_recovery_info’: drivers/i2c/busses/i2c-designware-master.c:658:6: warning: unused variable ‘r’ [-Wunused-variable] int r; ^ Fixes: 33eb09a02e8d ("i2c: designware: make use of devm_gpiod_get_optional") Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-08-01i2c: designware: make use of devm_gpiod_get_optionalUwe Kleine-König1-7/+4
There is a semantical change: if devm_gpiod_get_optional returns -ENOSYS this is passed as error to the caller. This effectively reverts commit d1fa74520dcd ("i2c: designware: Consider SCL GPIO optional") which shouldn't be necessary any more since gpiod_get_optional doesn't return -ENOSYS any more with GPIOLIB=n. Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org> 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>
2019-05-02i2c: designware: ratelimit 'transfer when suspended' errorsWolfram Sang1-2/+1
There are two problems with dev_err() here. One: It is not ratelimited. Two: We don't see which driver tried to transfer something with a suspended adapter. Switch to dev_WARN_ONCE to fix both issues. Drawback is that we don't see if multiple drivers are trying to transfer while suspended. They need to be discovered one after the other now. This is better than a high CPU load because a really broken driver might try to resend endlessly. Link: https://bugs.archlinux.org/task/62391 Fixes: 275154155538 ("i2c: designware: Do not allow i2c_dw_xfer() calls while suspended") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reported-by: skidnik <skidnik@gmail.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: skidnik <skidnik@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-02-23i2c: designware: Do not allow i2c_dw_xfer() calls while suspendedHans de Goede1-0/+6
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>
2018-10-11Merge tag 'v4.19-rc7' into i2c/for-4.20Wolfram Sang1-1/+3
This is the 4.19-rc7 release
2018-10-11i2c: designware: Set IRQF_NO_SUSPEND flag for all BYT and CHT controllersHans de Goede1-1/+1
On some Cherry Trail systems the GPU ACPI fwnode has power-resources which point to the PMIC, which is connected over a LPSS I2C controller. The GPU is a PCI device and PCI devices are powered-on at the resume_noirq resume phase. Since the GPU power-resources need the I2C controller, recent acpi_lpss.c changes now also power-up the LPSS I2C controllers on BYT and CHT devices in the resume_noirq resume phase. But during this phase the IRQ of the controller is disabled leading to these errors: 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 This commit makes the i2c-designware controller set the IRQF_NO_SUSPEND flag when requesting the interrupt on BYT and CHT devices, so that the IRQ is left enabled during the noirq phase, fixing this. Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-10-05i2c: designware: Call i2c_dw_clk_rate() only when calculating timingsJarkko Nikula1-1/+3
There are platforms which don't provide input clock rate but provide I2C timing parameters. Commit 3bd4f277274b ("i2c: designware: Call i2c_dw_clk_rate() only once in i2c_dw_init_master()") causes needless warning during probe on those platforms since i2c_dw_clk_rate(), which causes the warning when input clock is unknown, is called even when there is no need to calculate timing parameters. Fixes: 3bd4f277274b ("i2c: designware: Call i2c_dw_clk_rate() only once in i2c_dw_init_master()") Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: <stable@vger.kernel.org> # 4.19 Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-09-06i2c: designware: Remove Cherry Trail PMIC I2C bus pm_disabled workaroundHans de Goede1-1/+1
Commit a3d411fb38c0 ("i2c: designware: Disable pm for PMIC i2c-bus even if there is no _SEM method"), always set the pm_disabled flag on the I2C7 controller, even if its bus was not shared with the PUNIT. This was a workaround for various suspend/resume issues, after the following 2 commits this workaround is no longer necessary: Commit 541527728341 ("PM: i2c-designware-platdrv: Suspend/resume at the late/early stages") Commit e6ce0ce34f65 ("ACPI / LPSS: Add device link for CHT SD card dependency on I2C") Therefor this commit removes this workaround. After this commit the pm_disabled flag is only used to indicate that the bus is shared with the PUNIT and after other recent changes we no longer call dev_pm_syscore_device(dev, true), so we are no longer actually disabling (non-runtime) pm, so this commit also renames the flag to shared_with_punit to better reflect what it is for. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-30i2c: designware: Re-init controllers with pm_disabled set on resumeHans de Goede1-1/+0
On Bay Trail and Cherry Trail devices we set the pm_disabled flag for I2C busses which the OS shares with the PUNIT as these need special handling. Until now we called dev_pm_syscore_device(dev, true) for I2C controllers with this flag set to keep these I2C controllers always on. After commit 12864ff8545f ("ACPI / LPSS: Avoid PM quirks on suspend and resume from hibernation"), this no longer works. This commit modifies lpss_iosf_exit_d3_state() to only run if lpss_iosf_enter_d3_state() has ran before it, so that it does not run on a resume from hibernate (or from S3). On these systems the conditions for lpss_iosf_enter_d3_state() to run never become true, so lpss_iosf_exit_d3_state() never gets called and the 2 LPSS DMA controllers never get forced into D0 mode, instead they are left in their default automatic power-on when needed mode. The not forcing of D0 mode for the DMA controllers enables these systems to properly enter S0ix modes, which is a good thing. But after entering S0ix modes the I2C controller connected to the PMIC no longer works, leading to e.g. broken battery monitoring. The _PS3 method for this I2C controller looks like this: Method (_PS3, 0, NotSerialized) // _PS3: Power State 3 { If ((((PMID == 0x04) || (PMID == 0x05)) || (PMID == 0x06))) { Return (Zero) } PSAT |= 0x03 Local0 = PSAT /* \_SB_.I2C5.PSAT */ } Where PMID = 0x05, so we enter the Return (Zero) path on these systems. So even if we were to not call dev_pm_syscore_device(dev, true) the I2C controller will be left in D0 rather then be switched to D3. Yet on other Bay and Cherry Trail devices S0ix is not entered unless *all* I2C controllers are in D3 mode. This combined with the I2C controller no longer working now that we reach S0ix states on these systems leads to me believing that the PUNIT itself puts the I2C controller in D3 when all other conditions for entering S0ix states are true. Since now the I2C controller is put in D3 over a suspend/resume we must re-initialize it afterwards and that does indeed fix it no longer working. This commit implements this fix by: 1) Making the suspend_late callback a no-op if pm_disabled is set and making the resume_early callback skip the clock re-enable (since it now was not disabled) while still doing the necessary I2C controller re-init. 2) Removing the dev_pm_syscore_device(dev, true) call, so that the suspend and resume callbacks are actually called. Normally this would cause the ACPI pm code to call _PS3 putting the I2C controller in D3, wreaking havoc since it is shared with the PUNIT, but in this special case the _PS3 method is a no-op so we can safely allow a "fake" suspend / resume. Fixes: 12864ff8545f ("ACPI / LPSS: Avoid PM quirks on suspend and resume ...") Link: https://bugzilla.kernel.org/show_bug.cgi?id=200861 Cc: 4.15+ <stable@vger.kernel.org> # 4.15+ 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>
2018-08-20i2c: designware: Add SPDX license tagAndy Shevchenko1-14/+1
Replace short statement in comment with proper SPDX license tag. Note, for i2c-desingware-slave.c the identifier is chosen in accordance with MODULE_LICENSE() macro since it is visible to user. Another point to this choice is that the header seems to be copy'n'paste from the other file of this very driver. Acked-by: Luis Oliveira <Luis.Oliveira@synopsys.com> Signed-off-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>
2018-08-08i2c: designware: Convert to use struct i2c_timingsAndy Shevchenko1-3/+4
Instead of using custom variables and parser, convert the driver to use the ones provided by I2C core. No functional change intended. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Tested-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-04i2c: designware-master: use core to detect 'no zero length' quirkWolfram Sang1-7/+5
And don't reimplement in the driver. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: designware: Add debug print for bus speedJarkko Nikula1-2/+19
Trivial added debug print for dev->clk_freq doesn't necessarily tell the actual bus speed or mode the controller is operating. For instance it may indicate 1 MHz Fast Mode Plus or 3.4 MHz High Speed but driver ends up using 400 kHz Fast Mode due missing timing parameters or missing support from HW. Add a debug print that prints the bus speed based on the validated speed that gets programmed into a HW. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: designware: Separate timing parameter setting from HW initalizationJarkko Nikula1-50/+80
Mixed timing parameter validation, calculation and their debug prints with HW initialization in i2c_dw_init_master() and i2c_dw_init_slave() as been bothering me some time. It makes function a little bit unclear to follow, doesn't show what steps are needed to do only once during probe and what are needed whenever HW needs to be reinitialized. Also those debug prints show information that doesn't change runtime and thus are also needlessly printed multiple times whenever HW is reinitialized. Thus let the i2c_dw_init_master() and i2c_dw_init_slave() to do only HW initialization and move out one time parameter setting and debug prints to separate functions which are called only during probe. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: designware: Move SDA hold time configuration to common codeJarkko Nikula1-21/+12
SDA hold time configuration is common to both master and slave code. It is also something that can be done once during probe and do only register write when HW needs to be reinitialized. Remove duplication and move SDA hold time configuration to common code. It will be called from slave probe and for master code from a new i2c_dw_set_timings_master() to where we will populate more probe time timing parameter setting. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: designware: Call i2c_dw_clk_rate() only once in i2c_dw_init_master()Jarkko Nikula1-4/+5
This is rather readability update than micro-optimization, or if not optimization at all. We take the input clock rate to a variable and pass that to SCL timing parameter calculation functions. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-03i2c: designware: Move register access detection to common codeJarkko Nikula1-14/+4
Move register access detection out from master and slave HW initialization code to common code. Motivation for this is to have register access configured before HW initialization and remove duplicated code. This allows to do further separation between probe time initialization and runtime reinitialization code. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-15i2c: designware: refactor low-level enable/disableAlexander Monakov1-4/+4
Low-level controller enable function __i2c_dw_enable is overloaded to also handle disabling. What's worse, even though the documentation requires polling the IC_ENABLE_STATUS register when disabling, this is not done: polling needs to be requested specifically by calling __i2c_dw_enable_and_wait, which can also poll on enabling, but that doesn't work if the IC_ENABLE_STATUS register is not implemented. This is quite confusing if not in fact backwards. Especially since the documentation says that disabling should be followed by polling, the driver should be using a separate function where it does one-shot disables to make the optimization stand out. This refactors the two functions so that requested status is given in the name rather than in a boolean argument. Specifically: - __i2c_dw_enable: enable without polling (in accordance with docs) - __i2c_dw_disable: disable and do poll (also as suggested by docs) - __i2c_dw_disable_nowait: disable without polling (Linux-specific) No functional change. Signed-off-by: Alexander Monakov <amonakov@ispras.ru> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> [wsa: fixed blank lines in header file] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-10i2c: designware: fix poll-after-enable regressionAlexander Monakov1-1/+4
Not all revisions of DW I2C controller implement the enable status register. On platforms where that's the case (e.g. BG2CD and SPEAr ARM SoCs), waiting for enable will time out as reading the unimplemented register yields zero. It was observed that reading the IC_ENABLE_STATUS register once suffices to avoid getting it stuck on Bay Trail hardware, so replace polling with one dummy read of the register. Fixes: fba4adbbf670 ("i2c: designware: must wait for enable") Signed-off-by: Alexander Monakov <amonakov@ispras.ru> Tested-by: Ben Gardner <gardner.ben@gmail.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2018-03-17i2c: designware: suppress unneeded SDA hold time warningsAlexander Monakov1-1/+1
The hardware may not support SDA hold time configuration, but if it is not set in the Device Tree either, there is no need to print a warning. Reported-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com> Signed-off-by: Alexander Monakov <amonakov@ispras.ru> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-02-22i2c: designware: Consider SCL GPIO optionalAndy Shevchenko1-1/+1
GPIO library can return -ENOSYS for the failed request. Instead of failing ->probe() in this case override error code to 0. Fixes: ca382f5b38f3 ("i2c: designware: add i2c gpio recovery option") Reported-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-02-21i2c: designware: must wait for enableBen Gardner1-1/+1
One I2C bus on my Atom E3845 board has been broken since 4.9. It has two devices, both declared by ACPI and with built-in drivers. There are two back-to-back transactions originating from the kernel, one targeting each device. The first transaction works, the second one locks up the I2C controller. The controller never recovers. These kernel logs show up whenever an I2C transaction is attempted after this failure. i2c-designware-pci 0000:00:18.3: timeout in disabling adapter i2c-designware-pci 0000:00:18.3: timeout waiting for bus ready Waiting for the I2C controller status to indicate that it is enabled before programming it fixes the issue. I have tested this patch on 4.14 and 4.15. Fixes: commit 2702ea7dbec5 ("i2c: designware: wait for disable/enable only if necessary") Cc: linux-stable <stable@vger.kernel.org> #4.13+ Signed-off-by: Ben Gardner <gardner.ben@gmail.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: José Roberto de Souza <jose.souza@intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: designware: add i2c gpio recovery optionTim Sander1-0/+57
This patch contains much input from Phil Reid and has been tested on Intel/Altera Cyclone V SOC Hardware with Altera GPIO's for the SCL and SDA GPIO's. Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Tim Sander <tim@krieglstein.org> Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-07-04i2c: designware: Make HW init functions staticJarkko Nikula1-4/+3
Recent i2c-designware slave support patches use master or slave HW init functions through the function pointer so we can declare them static. While at it, rename i2c_dw_init() as i2c_dw_init_master(). Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Luis Oliveira <lolivei@synopsys.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-19i2c: designware: MASTER mode as separated driverLuis Oliveira1-0/+673
- The functions related to I2C master mode of operation were transformed in a single driver. - Common definitions were moved to i2c-designware-core.h - The i2c-designware-core is now only a library file, the functions associated are in a source file called i2c-designware-common and are used by both i2c-designware-master and i2c-designware-slave. - To decrease noise in namespace common i2c_dw_*() functions are now using ops to keep them private. - Designware PCI driver had to be changed to match the previous ops functions implementation. Almost all of the "core" source is now part of the "master" source. The difference is the functions used by both modes and they are in the "common" source file. Signed-off-by: Luis Oliveira <lolivei@synopsys.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>