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2020-10-21Merge branch 'i2c/for-5.10' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: - if a host can be a client, too, the I2C core can now use it to emulate SMBus HostNotify support (STM32 and R-Car added this so far) - also for client mode, a testunit has been added. It can create rare situations on the bus, so host controllers can be tested - a binding has been added to mark the bus as "single-master". This allows for better timeout detections - new driver for Mellanox Bluefield - massive refactoring of the Tegra driver - EEPROMs recognized by the at24 driver can now have custom names - rest is driver updates * 'i2c/for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (80 commits) Documentation: i2c: add testunit docs to index i2c: tegra: Improve driver module description i2c: tegra: Clean up whitespaces, newlines and indentation i2c: tegra: Clean up and improve comments i2c: tegra: Clean up printk messages i2c: tegra: Clean up variable names i2c: tegra: Improve formatting of variables i2c: tegra: Check errors for both positive and negative values i2c: tegra: Factor out hardware initialization into separate function i2c: tegra: Factor out register polling into separate function i2c: tegra: Factor out packet header setup from tegra_i2c_xfer_msg() i2c: tegra: Factor out error recovery from tegra_i2c_xfer_msg() i2c: tegra: Rename wait/poll functions i2c: tegra: Remove "dma" variable from tegra_i2c_xfer_msg() i2c: tegra: Remove redundant check in tegra_i2c_issue_bus_clear() i2c: tegra: Remove likely/unlikely from the code i2c: tegra: Remove outdated barrier() i2c: tegra: Clean up variable types i2c: tegra: Reorder location of functions in the code i2c: tegra: Clean up probe function ...
2020-09-21i2c: rcar: add HostNotify supportWolfram Sang
The I2C core can now utilize a slave interface to handle SMBus HostNotify events. Enable it in this driver. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-09-18i2c: rcar: refactor and shorten timeout when resettingWolfram Sang
LOOP_TIMEOUT was only used back then because we didn't want to introduce another constant. The timeout value can easily be a magnitude shorter because the typical range is 3us - 8us. Refactor the code to use the poll_timeout helper, use a specific timeout value and get rid of the ugly LOOP_TIMEOUT constant. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-09-18i2c: rcar: improve bus busy detectionWolfram Sang
I2C doesn't define a timeout for bus busy, so an arbitrary value like LOOP_TIMEOUT is not a good idea. Let's use the timeout value in struct adapter which is meant for such cases and is user-configurable (via IOCTL). To reduce the load, wait 10us instead of 1us which is good enough for the slow frequencies used by I2C. Finally, use the poll_timeout helper instead of open coding it. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-08-25i2c: rcar: in slave mode, clear NACK earlierWolfram Sang
Currently, a NACK in slave mode is set/cleared when SCL is held low by the IP core right before the bit is about to be pushed out. This is too late for clearing and then a NACK from the previous byte is still used for the current one. Now, let's clear the NACK right after we detected the STOP condition following the NACK. Fixes: de20d1857dd6 ("i2c: rcar: add slave support") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-31i2c: rcar: avoid race when unregistering slaveWolfram Sang
Due to the lockless design of the driver, it is theoretically possible to access a NULL pointer, if a slave interrupt was running while we were unregistering the slave. To make this rock solid, disable the interrupt for a short time while we are clearing the interrupt_enable register. This patch is purely based on code inspection. The OOPS is super-hard to trigger because clearing SAR (the address) makes interrupts even more unlikely to happen as well. While here, reinit SCR to SDBS because this bit should always be set according to documentation. There is no effect, though, because the interface is disabled. Fixes: 7b814d852af6 ("i2c: rcar: avoid race when unregistering slave client") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-31Merge tag 'v5.8-rc7' into i2c/for-5.9Wolfram Sang
2020-07-26i2c: rcar: slave: only send STOP event when we have been addressedWolfram Sang
When the SSR interrupt is activated, it will detect every STOP condition on the bus, not only the ones after we have been addressed. So, enable this interrupt only after we have been addressed, and disable it otherwise. Fixes: de20d1857dd6 ("i2c: rcar: add slave support") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-07-23i2c: rcar: always clear ICSAR to avoid side effectsWolfram Sang
On R-Car Gen2, we get a timeout when reading from the address set in ICSAR, even though the slave interface is disabled. Clearing it fixes this situation. Note that Gen3 is not affected. To reproduce: bind and undbind an I2C slave on some bus, run 'i2cdetect' on that bus. Fixes: de20d1857dd6 ("i2c: rcar: add slave support") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2020-04-15i2c: busses: convert to devm_platform_get_and_ioremap_resourceDejin Zheng
use devm_platform_get_and_ioremap_resource() to simplify code, which contains platform_get_resource() and devm_ioremap_resource(), it also get the resource for use by the following code. Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-03-31i2c: rcar: clean up after refactoring i2c_timingsWolfram Sang
The pointer is not really needed anymore since we have the timings struct available in the function itself now. Remove the pointer and access the struct directly. 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>
2020-03-24i2c: rcar: Consolidate timings calls in rcar_i2c_clock_calculate()Andy Shevchenko
Move i2c_parse_fw_timings() to rcar_i2c_clock_calculate() to consolidate timings calls in one place. While here, replace hard coded values with standard bus frequency definitions. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2020-03-24i2c: core: Allow override timing properties with 0Andy Shevchenko
Some drivers may allow to override properties with 0 value when defaults are not in use, thus, replace memset() with corresponding per property update. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-11-14i2c: rcar: Remove superfluous call to clk_get_rate()Geert Uytterhoeven
Variable "rate" already contains the current clock rate, so use that rather than calling clk_get_rate() again. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-08-14i2c: rcar: avoid race when unregistering slave clientWolfram Sang
After we disabled interrupts, there might still be an active one running. Sync before clearing the pointer to the slave device. Fixes: de20d1857dd6 ("i2c: rcar: add slave support") Reported-by: Krzysztof Adamski <krzysztof.adamski@nokia.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Krzysztof Adamski <krzysztof.adamski@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-03-20i2c: rcar: wait for data empty before starting DMAWolfram Sang
When sending with DMA, the driver transfers the first byte with PIO (as documented). However, it started DMA right after the first byte was written. This worked, but was not according to the datasheet which suggests to wait until data register was empty again. Implement this. 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>
2019-03-20i2c: rcar: let DMA enable routine return success statusWolfram Sang
We will need to know if enabling DMA was successful in a later patch. 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>
2019-03-20i2c: rcar: sanity check for minimal DMA lengthWolfram Sang
Use a macro for the hardcoded value and apply a build check. If it is not met, the driver logic will not work anymore. 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>
2019-03-12i2c: rcar: explain the lockless designWolfram Sang
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 Yamasaki
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>
2019-02-08i2c: rcar: refactor TCYC handlingWolfram Sang
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>
2019-02-05i2c: rcar: comment maintenanceWolfram Sang
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>
2019-01-22i2c: rcar: Fix clients using i2c from suspend callbackGeert Uytterhoeven
When doing s2idle/s2ram on Salvator-X(S): WARNING: CPU: 2 PID: 971 at drivers/i2c/i2c-core-base.c:1869 __i2c_transfer+0x608/0x910 [...] Call trace: __i2c_transfer+0x608/0x910 i2c_smbus_xfer_emulated+0x158/0x5b0 __i2c_smbus_xfer+0x17c/0x818 i2c_smbus_xfer+0x64/0x98 i2c_smbus_read_byte_data+0x40/0x70 cs2000_bset.isra.1+0x2c/0x68 __cs2000_set_rate.constprop.7+0x80/0x148 cs2000_resume+0x18/0x20 dpm_run_callback+0x74/0x330 device_resume_early+0xd4/0x120 dpm_resume_early+0x158/0x4f8 suspend_devices_and_enter+0x36c/0xd98 [...] On second resume, the sound driver fails with: cs2000-cp 2-004f: pll lock failed rcar_sound ec500000.sound: can't use clk 1 As the CS2000 clock driver needs to send I2C messages during suspend, the I2C controller driver should be suspended later, and resumed earlier. Fix this by using the noirq sleep ops instead of the normal sleep ops, which are called after the late sleep ops, as used by the CS2000 clock driver. Fixes: 18569fa89a4db9ed ("i2c: rcar: add suspend/resume support") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2019-01-08i2c: rcar: add suspend/resume supportWolfram Sang
Because the adapter will be set up before every transaction anyhow, we just need to mark it as suspended to the I2C core. Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-11-27i2c: rcar: check bus state before reinitializingWolfram Sang
We should check the bus state before reinitializing the IP core. Otherwise, the internal bus busy state which also tracks multi-master activity is lost. Credits go to the Renesas BSP team for suggesting this change. Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Fixes: ae481cc13965 ("i2c: rcar: fix resume by always initializing registers before transfer") Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-10-20i2c: rcar: cleanup DMA for all kinds of failureWolfram Sang
DMA needs to be cleaned up not only on timeout, but on all errors where it has been setup before. Fixes: 73e8b0528346 ("i2c: rcar: add DMA support") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-24i2c: use SPDX identifier for Renesas driversWolfram Sang
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>
2018-08-20i2c: rcar: implement STOP and REP_START according to docsWolfram Sang
When doing a REP_START after a read message, the driver used to trigger a STOP first which would then be overwritten by REP_START. This was the only stable method found when doing the last refactoring. However, this was not in accordance with the documentation. After research from our BSP team and myself, we now can implement a version which works and is according to the documentation. The new approach ensures the ICMCR register is only changed when really needed. Tested on a R-Car Gen2 (H2) and Gen3 with DMA (M3N). Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-20i2c: rcar: refactor private flagsWolfram Sang
Use BIT macro to avoid shift-31-problem, indent a little more and use GENMASK to make it easier to add new flags. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-08-04i2c: rcar: use core to detect 'no zero length' quirkWolfram Sang
And don't reimplement in the driver. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-07-23i2c: rcar: handle RXDMA HW behaviour on Gen3Wolfram Sang
On Gen3, we can only do RXDMA once per transfer reliably. For that, we must reset the device, then we can have RXDMA once. This patch implements this. When there is no reset controller or the reset fails, RXDMA will be blocked completely. Otherwise, it will be disabled after the first RXDMA transfer. Based on a commit from the BSP by Hiromitsu Yamasaki, yet completely refactored to handle multiple read messages within one transfer. 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>
2018-07-17i2c: rcar: use the new get_bus_free callbackWolfram Sang
To break out of recovery as early as possible, feed back the bus_free logic state. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-05-29i2c: busses: make use of i2c_8bit_addr_from_msgPeter Rosin
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>
2018-04-30i2c: rcar: enhance comment to avoid regressionsWolfram Sang
Give a clear testcase for people wishing to change this code. It is also a reminder for me if people ask about it. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-03-24i2c: rcar: fix mask value of prohibited bitHiromitsu Yamasaki
According to documentation, Bit 7 of ICMSR is unused and 0 should be written to it. Fix the mask accordingly. Signed-off-by: Hiromitsu Yamasaki <hiromitsu.yamasaki.ym@renesas.com> [wsa: edited commit message] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-24i2c: rcar: fix some trivial typos in commentsWolfram Sang
Nothing big, but they get annoying after a while ;) Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-16i2c: rcar: implement bus recoveryWolfram Sang
We can force levels of SCL and SDA, so we can use that for bus recovery. Note that we cannot read SDA back, because we will only get the internal state of the bus free detection. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03i2c: rcar: skip DMA if buffer is not safeWolfram Sang
This HW is prone to races, so it needs to setup new messages in irq context. That means we can't alloc bounce buffers if a message buffer is not DMA safe. So, in that case, simply fall back to PIO. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-08-17i2c: rcar: avoid unused ret variableEugeniu Rosca
Fix smatch warning: drivers/i2c/busses/i2c-rcar.c:628 \ rcar_i2c_request_dma_chan() warn: unused return: ret = PTR_ERR() Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-07-12Merge branch 'i2c/for-4.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "This pull request contains: - i2c core reorganization. One source file became too monolithic. It is now split up, yet we still have the same named object as the final output. This should ease maintenance. - new drivers: ZTE ZX2967 family, ASPEED 24XX/25XX - designware driver gained slave mode support - xgene-slimpro driver gained ACPI support - bigger overhaul for pca-platform driver - the algo-bit module now supports messages with enforced STOP - slightly bigger than usual set of driver updates and improvements and with much appreciated quality assurance from Andy Shevchenko" * 'i2c/for-4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (51 commits) i2c: Provide a stub for i2c_detect_slave_mode() i2c: designware: Let slave adapter support be optional i2c: designware: Make HW init functions static i2c: designware: fix spelling mistakes i2c: pca-platform: propagate error from i2c_pca_add_numbered_bus i2c: pca-platform: correctly set algo_data.reset_chip i2c: acpi: Do not create i2c-clients for LNXVIDEO ACPI devices i2c: designware: enable SLAVE in platform module i2c: designware: add SLAVE mode functions i2c: zx2967: drop COMPILE_TEST dependency i2c: zx2967: always use the same device when printing errors i2c: pca-platform: use dev_warn/dev_info instead of printk i2c: pca-platform: use device managed allocations i2c: pca-platform: add devicetree awareness i2c: pca-platform: switch to struct gpio_desc dt-bindings: add bindings for i2c-pca-platform i2c: cadance: fix ctrl/addr reg write order i2c: zx2967: add i2c controller driver for ZTE's zx2967 family dt: bindings: add documentation for zx2967 family i2c controller i2c: algo-bit: add support for I2C_M_STOP ...
2017-06-23i2c: rcar: document HW incapabilitiesWolfram Sang
Add recent findings (IGNORE_NAK) and document in a bit more detail why the feature is not possible. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-19i2c: use proper name for the R-Car SoCWolfram Sang
It is 'R-Car', not 'RCar'. No code or binding changes, only descriptive text. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-06-15i2c: rcar: use correct length when unmapping DMAWolfram Sang
Because we need to transfer some bytes with PIO, the msg length is not the length of the DMA buffer. Use the correct value which we used when doing the mapping. Fixes: 73e8b0528346e8 ("i2c: rcar: add DMA support") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-04-21i2c: rcar: clarify PM handling with more commentsWolfram Sang
PM handling is correct but might be a bit subtle. Add some comments for clarification. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-04-21i2c: rcar: fix resume by always initializing registers before transferWolfram Sang
Resume failed because of uninitialized registers. Instead of adding a resume callback, we simply initialize registers before every transfer. This lightweight change is more robust and will keep us safe if we ever need support for power domains or dynamic frequency changes. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-12-11i2c: rcar: Add per-Generation fallback bindingsSimon Horman
In the case of Renesas R-Car hardware we know that there are generations of SoCs, e.g. Gen 2 and Gen 3. But beyond that it's not clear what the relationship between IP blocks might be. For example, I believe that r8a7790 is older than r8a7791 but that doesn't imply that the latter is a descendant of the former or vice versa. We can, however, by examining the documentation and behaviour of the hardware at run-time observe that the current driver implementation appears to be compatible with the IP blocks on SoCs within a given generation. For the above reasons and convenience when enabling new SoCs a per-generation fallback compatibility string scheme is being adopted for drivers for Renesas SoCs. Also: * Deprecate renesas,i2c-rcar. It seems poorly named as it is only compatible with R-Car Gen 1. It also appears unused in mainline. * Add some text to describe per-SoC bindings Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-10-07Merge branch 'i2c/for-4.9' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c updates from Wolfram Sang: "Here is the 4.9 pull request from I2C including: - centralized error messages when registering to the core - improved lockdep annotations to prevent false positives - DT support for muxes, gates, and arbitrators - bus speeds can now be obtained from ACPI - i2c-octeon got refactored and now supports ThunderX SoCs, too - i2c-tegra and i2c-designware got a bigger bunch of updates - a couple of standard driver fixes and improvements" * 'i2c/for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (71 commits) i2c: axxia: disable clks in case of failure in probe i2c: octeon: thunderx: Limit register access retries i2c: uniphier-f: fix misdetection of incomplete STOP condition gpio: pca953x: variable 'id' was used twice i2c: i801: Add support for Kaby Lake PCH-H gpio: pca953x: fix an incorrect lockdep warning i2c: add a warning to i2c_adapter_depth() lockdep: make MAX_LOCKDEP_SUBCLASSES unconditionally visible i2c: export i2c_adapter_depth() i2c: rk3x: Fix variable 'min_total_ns' unused warning i2c: rk3x: Fix sparse warning i2c / ACPI: Do not touch an I2C device if it belongs to another adapter i2c: octeon: Fix high-level controller status check i2c: octeon: Avoid sending STOP during recovery i2c: octeon: Fix set SCL recovery function i2c: rcar: add support for r8a7796 (R-Car M3-W) i2c: imx: make bus recovery through pinctrl optional i2c: meson: add gxbb compatible string i2c: uniphier-f: set the adapter to master mode when probing i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure path ...
2016-09-16i2c: rcar: add support for r8a7796 (R-Car M3-W)Ulrich Hecht
Same as r8a7795. Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-08-25i2c: rcar: use proper device with dma_mapping_errorWolfram Sang
We must use the same device we used for mapping. 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>
2016-08-22i2c: don't print error when adding adapter failsWolfram Sang
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>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-02 10:26:46 +0000