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* i2c: sh_mobile: avoid unused ret variableEugeniu Rosca2017-08-171-2/+2
| | | | | | | | | Fix smatch warning: drivers/i2c/busses/i2c-sh_mobile.c:564 \ sh_mobile_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>
* i2c: sh_mobile: drop needless check for of_nodeWolfram Sang2017-06-021-12/+7
| | | | | | | | | | After removal of platform_data support, we can simplify OF handling. of_match_device() evaluates to NULL if !CONFIG_OF or if there is no node pointer for that device, so we can remove the check for the node ptr. 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>
* i2c: sh_mobile: remove platform_dataWolfram Sang2017-06-021-8/+0
| | | | | | | | | | | | | No platform currently upstream makes use of this platform_data anymore. The ones that did are converted to DT meanwhile. So, remove it. The old platforms likely don't have the 'clks_per_cnt' feature, otherwise it would have been implemented by now. And in the unlikely case they need to setup a different bus speed, we should rather go for a generic i2c platform data just for that. 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>
* i2c: busses: constify i2c_algorithm structuresBhumika Goyal2017-02-091-1/+1
| | | | | | | | | | | | | | Declare i2c_algorithm structures as const as they are only stored in the algo field of an i2c_adapter structure. This field is of type const, so i2c_algorithm structures having this property can be made const too. Signed-off-by: Bhumika Goyal <bhumirks@gmail.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> for Acked-by: Patrice Chotard <patrice.chotard@st.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: Add per-Generation fallback bindingsSimon Horman2016-12-111-1/+3
| | | | | | | | | | | | | | | Add per-Generation fallback bindings for R-Car SoCs. This is in keeping with the compatibility string scheme is being adopted for drivers for Renesas SoCs. Also, improve readability by listing the rmobile fallback compatibility string after the more-specific compatibility strings they provide a fallback for. Signed-off-by: Simon Horman <horms+renesas@verge.net.au> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* Merge branch 'i2c/for-4.9' of ↵Linus Torvalds2016-10-071-1/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * i2c: don't print error when adding adapter failsWolfram Sang2016-08-221-1/+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>
* | i2c: sh_mobile: use proper device with dma_mapping_errorWolfram Sang2016-08-251-1/+1
|/ | | | | | | | 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>
* i2c: sh_mobile: use new 8 bit address helper functionWolfram Sang2016-04-111-2/+1
| | | | | Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: add support for r8a7795 (R-Car H3)Wolfram Sang2015-10-201-0/+1
| | | | | | | | | Enable the I2C core for this SoC. It is compitable to Gen2 SoCs, so reuse the settings. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: use proper type for timeoutWolfram Sang2015-06-231-3/+4
| | | | | | | | wait_event_timeout returns long, not int. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: use adapter default for timeoutWolfram Sang2015-06-231-1/+1
| | | | | | | | | | 5 seconds is a very large timeout, and it is hardcoded. Use the default timeout from 'struct adapter' which is 1 second. It can also be modified from userspace for specific workloads via i2c-dev. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: add errata workaroundWolfram Sang2015-06-171-0/+40
| | | | | | | | | | | This used to be in platform init code. We want it to do in the driver now. This is basically a code move and a new compatible added. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Acked-by: Simon Horman <horms+renesas@verge.net.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: terminate DMA reads properlyWolfram Sang2015-01-301-1/+11
| | | | | | | | | DMA read requests could miss proper termination, so two more bytes would have been read via PIO overwriting the end of the buffer with wrong data. Make DMA stop handling more readable while we are here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: fix uninitialized var when debug is enabledWolfram Sang2014-12-201-0/+1
| | | | | Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: rework deferred probingWolfram Sang2014-12-171-50/+48
| | | | | | | | | | | | | | | DMA is opt-in for this driver. So, we can't use deferred probing for requesting DMA channels in probe, because our driver would get endlessly deferred if DMA support is compiled in AND the DMA driver is missing. Because we can't know when the DMA driver might show up, we always try again when a DMA transfer would be possible. The downside is that there is more overhead for setting up PIO transfers under the above scenario. But well, having DMA enabled and the proper DMA driver missing looks like a broken or test config anyhow. Reported-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: refactor DMA setupWolfram Sang2014-12-171-19/+16
| | | | | | | | Refactor DMA setup to keep the errno so we can implement better deferred probe support in the next step. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* Merge tag 'driver-core-3.19-rc1' of ↵Linus Torvalds2014-12-151-1/+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 ...
| * i2c: busses: drop owner assignment from platform_driversWolfram Sang2014-10-201-1/+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>
* | i2c: sh_mobile: remove unneeded DMA maskWolfram Sang2014-12-111-3/+0
| | | | | | | | | | | | | | We don't need the mask since we obtain the channels via DT. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* | i2c: sh_mobile: optimize irq entryWolfram Sang2014-12-041-5/+4
| | | | | | | | | | | | | | | | | | | | We can simply pass the pointer to the private structure to the irq routine instead of passing the platform device and looking up its driver_data. 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>
* | i2c: sh_mobile: use proper device for mapping DMA memoryWolfram Sang2014-11-191-9/+14
| | | | | | | | | | | | | | | | It should be the DMA device, not the platform device. 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>
* | i2c: sh_mobile: improve success messageWolfram Sang2014-11-121-3/+3
| | | | | | | | | | | | | | No user needs magic hex values, makes this debug output. Add DMA info. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* | i2c: sh_mobile: add DMA supportWolfram Sang2014-11-121-10/+185
| | | | | | | | | | | | | | | | | | | | | | | | | | Make it possible to transfer i2c message buffers via DMA. Start/Stop/Sending_Slave_Address is still handled using the old state machine, it is sending the actual data that is done via DMA. This is least intrusive and allows us to work with the message buffers directly instead of preparing a custom buffer which involves copying the data around. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> [wsa: fixed an uninitialized var problem] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* | i2c: sh_mobile: sort includes alphabeticallyWolfram Sang2014-11-121-9/+9
| | | | | | | | | | | | | | Improves readability and reduces chances of duplicates. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* | i2c: sh_mobile: Add support for r8a73a4 and sh73a0Geert Uytterhoeven2014-11-101-6/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | Add support for r8a73a4 (R-Mobile APE6) and sh73a0 (SH-Mobile AG5). On these SoCs, the operating clock runs faster that on previous SoCs, and the internal SCL clock counter gets incremented every 2 clocks of the operating clock, just like on R-Car Gen2. Cfr. the "/2" in the calculation of ICCL/ICCH in section "I2C Bus Interface (IIC)", subsection "Transfer Rate" of the datasheets. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* | i2c: remove FSF addressWolfram Sang2014-11-071-4/+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>
* i2c: sh_mobile: add compatibles for additional SoCWolfram Sang2014-06-011-0/+3
| | | | | Signed-off-by: Wolfram Sang <wsa@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: fix clock calculation for newer SoCsWolfram Sang2014-05-221-10/+38
| | | | | | | | | | Newer SoCs have so fast input clocks that the ICCL/H registers only count every second clock to have a meaningful 9-bit range. The driver was already prepared for that happening, but didn't use it so far. Add the proper DT configuration for SoCs that need it. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: check timing parameters for valid rangeWolfram Sang2014-05-221-4/+13
| | | | | | | | | | Due to misconfiguration, it can happen that the calculated timing parameters are out of range. Bail out if that happens. We can also simplify some logic later because of the verified value. Also, make the printouts of the values more precise by adding the hex-prefixes. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: bail out on errors when initializingWolfram Sang2014-05-221-5/+7
| | | | | | | | sh_mobile_i2c_init() could detect wrong settings, but didn't bail out, so it would continue unconfigured. Fix this. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: remove superfluous offset parameterWolfram Sang2014-05-221-9/+6
| | | | | | | Following the KISS principle, remove unneeded stuff. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: devm conversion, irq setupWolfram Sang2014-05-221-41/+15
| | | | | | | | | | This is what devm was made for. No rollback mechanism needed, remove the hook parameter from the irq setup function and simplify it. While we are here change some variables to proper types. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: devm conversion, low hanging fruitsWolfram Sang2014-05-221-31/+10
| | | | | | | | | Convert the easy parts to devm. irqs will be converted in a seperate patch to keep diffs readable. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: honor DT bus speed settingsWolfram Sang2014-05-221-1/+4
| | | | | Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: improve error handlingWolfram Sang2014-05-221-16/+9
| | | | | | | | | Use standard i2c error codes for i2c failures. Also, don't print something on timeout since it happens regularly with i2c. Simplify some, logic, too. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: replace magic hex values with constantsWolfram Sang2014-05-221-5/+6
| | | | | | | No functional change, binaries are identical. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: Convert to clk_prepare/unprepareLaurent Pinchart2013-10-311-4/+4
| | | | | | | | | Turn clk_enable() and clk_disable() calls into clk_prepare_enable() and clk_disable_unprepare() to get ready for the migration to the common clock framework. Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: move OF helpers into the coreWolfram Sang2013-08-231-2/+0
| | | | | | | | | | I2C of helpers used to live in of_i2c.c but experience (from SPI) shows that it is much cleaner to have this in the core. This also removes a circular dependency between the helpers and the core, and so we can finally register child nodes in the core instead of doing this manually in each driver. So, fix the drivers and documentation, too. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: use dev_get_platdata()Jingoo Han2013-08-191-1/+1
| | | | | | | | Use the wrapper function for retrieving the platform data instead of accessing dev->platform_data directly. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: sh_mobile: don't send a stop condition by default inside transfersGuennadi Liakhovetski2013-02-101-20/+59
| | | | | | | | | By default there should be no stop bit on I2C between single messages within transfers. Fix the driver to comply and only send a stop bit at the end of transfers or if I2C_M_STOP is set. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
* i2c: sh_mobile: eliminate an open-coded "goto" loopGuennadi Liakhovetski2013-02-101-26/+34
| | | | | | | Eliminate an open-coded "goto" loop by introducing a function. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
* i2c: sh_mobile: fix timeout error handlingGuennadi Liakhovetski2013-02-101-1/+4
| | | | | | | | | In a timeout case return an error immediately from the driver's .master_xfer() method, instead of continuing and letting higher layers fail. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
* i2c: sh_mobile: cosmetic: trivially simplify 2 functionsGuennadi Liakhovetski2013-02-101-10/+4
| | | | | | | | Reduce 2 boolean functions from "if (condition) return 1; return 0;" to "return condition;" Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Wolfram Sang <wolfram@the-dreams.de>
* i2c: remove __dev* attributes from subsystemBill Pemberton2012-12-221-1/+1
| | | | | | | | | | | | | | | | | CONFIG_HOTPLUG is going away as an option. As result the __dev* markings will be going away. Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst, and __devexit. Signed-off-by: Bill Pemberton <wfp5p@virginia.edu> Acked-by: Peter Korsgaard <peter.korsgaard@barco.com> (for ocores and mux-gpio) Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com> (for i2c-gpio) Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn> (for puf3) Acked-by: Barry Song <baohua.song@csr.com> (for sirf) Reviewed-by: Jean Delvare <khali@linux-fr.org> [wsa: Fixed "foo* bar" flaws while we are here] Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-sh_mobile: fix spurious transfer request timed outShinya Kuribayashi2012-11-161-0/+3
| | | | | | | | | | | | | Ensure that any of preceding register write operations to the I2C hardware block reached the module, and the write data is reflected in the registers, before leaving the interrupt handler. Otherwise, we'll suffer from spurious WAIT interrupts that lead to 'Transfer request timed out' message, and the transaction failed. Reported-by: Teppei Kamijou <teppei.kamijou.yb@renesas.com> Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-sh_mobile: support I2C hardware block with a faster operating clockShinya Kuribayashi2012-11-161-0/+5
| | | | | | | | | | | | | | | On newer SH-/R-Mobile SoCs, a clock supply to the I2C hardware block, which is used to generate the SCL clock output, is getting faster than before, while on the other hand, the SCL clock control registers, ICCH and ICCL, stay unchanged in 9-bit-wide (8+1). On such silicons, the internal SCL clock counter gets incremented every 2 clocks of the operating clock. This patch makes it configurable through platform data. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-sh_mobile: optimize ICCH/ICCL values according to I2C bus speedShinya Kuribayashi2012-11-161-49/+77
| | | | | | | | | | | | | | | | | | ICCH/ICCL values is supposed to be calculated/optimized to strictly meet the timing specs required by the I2C standard. The resulting I2C bus speed does not matter at all, if it's less than 100 or 400 kHz. With this change, sh_mobile_i2c_icch() is virtually identical to sh_mobile_i2c_iccl(), but they're providing good descriptions of SH-/R-Mobile I2C hardware spec, and I'd leave them as separated. Also fix a typo in the comment, print icch/iccl values at probe, etc. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com> [wsa: squashed two patches for bisectability] Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: i2c-sh_mobile: calculate clock parameters at driver probing timeShinya Kuribayashi2012-11-161-5/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently SCL clock parameters (ICCH/ICCL) are calculated in activate_ch(), which gets called every time sh_mobile_i2c_xfer() is processed, while each I2C bus speed is system-defined and in general those parameters do not have to be updated over I2C transactions. The only reason I could see having it transaction-time is to adjust ICCH/ICCL values according to the operating frequency of the I2C hardware block, in the face of DFS (Dynamic Frequency Scaling). However, this won't be necessary. The operating frequency of the I2C hardware block can change _even_ in the middle of I2C transactions. There is no way to prevent it from happening, and I2C hardware block can work with such dynamic frequency change, of course. Another is that ICCH/ICCL clock parameters optimized for the faster operating frequency, can also be applied to the slower operating frequency, as long as slave devices work. However, the converse is not true. It would violate SCL timing specs of the I2C standard. What we can do now is to calculate the ICCH/ICCL clock parameters according to the fastest operating clock of the I2C hardware block. And if that's the case, that calculation should be done just once at driver-module-init time. This patch moves ICCH/ICCL calculating part from activate_ch() into sh_mobile_i2c_init(), and call it from sh_mobile_i2c_probe(). Note that sh_mobile_i2c_init() just prepares clock parameters using the clock rate and platform data provided, but does _not_ make any hardware I/O accesses. We don't have to care about run-time PM maintenance here. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c: sh_mobile: add device tree supportMagnus Damm2012-05-121-0/+11
| | | | | | | | | | | | | This patch enables DT support for the IIC driver used on SH-based SoCs such as sh7722 and sh7724 among others as well as SH-Mobile SoCs such as sh7367, sh7377, sh7372, sh73a0 and r8a7740. Tested with out-of-tree DT support code on the sh7372 Mackerel board. Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>