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2018-01-15i2c: mpc: unify obtaining the MPC8533/44 I2C clock prescaler w/ MPC8xxxArseny Solokha1-3/+9
Commit 8ce795cb0c6b ("i2c: mpc: assign the correct prescaler from SVR") introduced the common helper function for obtaining the actual clock prescaler value for MPC85xx. However, getting the prescaler for MPC8544 which depends on the SEC frequency ratio on this platform, has been always performed separately based on the corresponding Device Tree configuration. Move special handling of MPC8544 into that common helper. Make it dependent on the SoC version and not on Device Tree compatible node, as is the case with all other SoCs. Handle MPC8533 the same way which is similar to MPC8544 in this regard, according to AN2919 "Determining the I2C Frequency Divider Ratio for SCL". Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: mpc: get MPC8xxx I2C clock prescaler before using it in calculationsArseny Solokha1-6/+6
Obtaining the actual I2C clock prescaler value in mpc_i2c_setup_8xxx() only happens when the clock parameter is set to something other than MPC_I2C_CLOCK_LEGACY. When the clock parameter is exactly MPC_I2C_CLOCK_LEGACY, the prescaler parameter is used in arithmetic division as provided by the caller, resulting in a division by zero for the majority of processors supported by the module. Avoid division by zero by obtaining the actual I2C clock prescaler in mpc_i2c_setup_8xxx() unconditionally regardless of the passed clock value. Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: ismt: dump registers at the end of transactionsRadu Rendec1-0/+2
This patch dumps general and master registers at the end of transactions when debugging is enabled. Previously, registers were only dumped before submitting new descriptors (at the beginning of transactions). This helps debugging if some registers change as result of a failed transaction (e.g. bits are set in the ERRSTS general register). Signed-off-by: Radu Rendec <radu.rendec@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: sh_mobile: let r8a7790 (R-Car H2) use the new formulaWolfram Sang1-1/+1
Make use of the new formula for more precise bus frequencies. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: sh_mobile: add new frequency calculation for later SoCWolfram Sang1-1/+18
The formula to generate the desired bus speeds has changed a little over time. Implement the new formula and allow drivers to opt-in by changing to this new config set. Ensure in probe that we don't divide by zero. The returned values on a R-Car H2 (r8a7790/Lager board) match the suggested values in the datasheet. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: sh_mobile: add helper to check frequency calculationsWolfram Sang1-22/+27
Because we will add a second formula soon, put the sanity checks for the computed results into a separate function. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: sh_mobile: let RuntimePM do the clock handlingWolfram Sang1-18/+17
Start RuntimePM a bit earlier, so we can use it to enable the clock during probe for frequency calculations. Make sure it is enabled before calling setup(). Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: sh_mobile: require setup callbackWolfram Sang1-9/+6
Require the setup callback and move the frequency calculation into it. This is in preparation for supporting multiple formulas. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: sh_mobile: allow setup callback to return errnoWolfram Sang1-4/+9
The setup callback will be more generic and, thus, need to be able to return error codes. Change the return type to 'int' for that. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-15i2c: sh_mobile: move type detection upwardsWolfram Sang1-6/+4
For refactoring reasons, we will need this information before the setup callback. Also, simplify the comment to a oneliner. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-04i2c: gpio: Enable working over slow can_sleep GPIOsJan Kundrát1-4/+7
"Slow" GPIOs (usually those connected over an SPI or an I2C bus) are, well, slow in their operation. It is generally a good idea to avoid using them for time-critical operation, but sometimes the hardware just sucks, and the software has to cope. In addition to that, the I2C bus itself does not actually define any strict timing limits; the bus is free to go all the way down to DC. The timeouts (and therefore the slowest acceptable frequency) are present only in SMBus. The `can_sleep` is IMHO a wrong concept to use here. My SPI-to-quad-UART chip (MAX14830) is connected via a 26MHz SPI bus, and it happily drives SCL at 200kHz (5µs pulses) during my benchmarks. That's faster than the maximal allowed speed of the traditional I2C. The previous version of this code did not really block operation over slow GPIO pins, anyway. Instead, it just resorted to printing a warning with a backtrace each time a GPIO pin was accessed, thereby slowing things down even more. Finally, it's not just me. A similar patch was originally submitted in 2015 [1]. [1] https://patchwork.ozlabs.org/patch/450956/ Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-04i2c: mediatek: Enable i2c module clock before i2c registers access.Jun Gao1-0/+9
Make sure i2c module clock has been enabled before i2c registers access. Signed-off-by: Jun Gao <jun.gao@mediatek.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-04i2c: mediatek: Add i2c compatible for MediaTek MT2712Jun Gao1-4/+27
Add i2c compatible for MT2712. Compare to MT8173 i2c controller, internal divider of i2c source clock need to be configured for MT2712 i2c speed calculation. Signed-off-by: Jun Gao <jun.gao@mediatek.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2018-01-03Merge tag 'at24-4.16-updates-for-wolfram' of ↵Wolfram Sang5-5/+8
git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into i2c/for-4.16 "AT24 updates for 4.16 merge window The driver has been converted to using regmap instead of raw i2c and smbus calls which shrank the code significantly. Device tree binding document has been cleaned up. Device tree support in the driver has been improved and we now support all at24 models as well as two new DT properties (no-read-rollover and wp-gpios). We no longer user unreadable magic values for driver data as the way it was implemented caused problems for some EEPROM models - we switched to regular structs. Aside from that, there's a bunch of coding style fixes and minor improvements all over the place."
2017-12-31Merge branch 'i2c-mux/for-next' of https://github.com/peda-r/i2c-mux into ↵Wolfram Sang5-7/+45
i2c/for-4.16 "A couple of patches this time. Just some more compatibles for the pca954x driver and an error handling tweak for the reg driver."
2017-12-31i2c: ismt: Use %pad specifier for dma_addr_t variablesAndy Shevchenko1-2/+1
...which takes care of proper format and size of the value. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-31i2c: algo-bit: init the bus to a known stateWolfram Sang1-0/+5
Ensure the bus is free when we register the adapter. Before the SCL/SDA wires were in an unknown state. It used to work because sending a byte has a retry mechanism which was triggered if the bus was initially in a non-free state. But the graceful way to do it is to initialize correctly. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-31i2c/ARM: davinci: Deep refactoring of I2C recoveryLinus Walleij1-10/+11
Alter the DaVinci GPIO recovery fetch to use descriptors all the way down into the board files. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Sekhar Nori <nsekhar@ti.com> Tested-by: Sekhar Nori <nsekhar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-30i2c: mux: reg: don't log an error for probe deferralTomasz Bachorski1-0/+3
It's possible that i2c_mux_reg_probe_dt() could return -EPROBE_DEFER. In that case, driver will request a probe deferral and an error suggesting device tree parsing problem will be reported. This is a pretty confusing information. Let's change the error handling, so driver will be able to request probe deferral without logging not related errors. Signed-off-by: Tomasz Bachorski <tomasz.bachorski@nokia.com> Signed-off-by: Peter Rosin <peda@axentia.se>
2017-12-30i2c: mux: pca954x: add support for NXP PCA984x familyAdrian Fiergolski2-7/+37
This patch extends the current i2c-mux-pca954x driver and adds support for a newer PCA984x family of the I2C switches and multiplexers from NXP. Signed-off-by: Adrian Fiergolski <adrian.fiergolski@cern.ch> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Rosin <peda@axentia.se>
2017-12-12i2c: imx: Include the right GPIO headerLinus Walleij1-1/+1
<linux/of_gpio.h> is not used in this file, by <linux/gpio/consumer.h> is. Someone is just lucky with their implicit includes. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-12i2c: piix4: Fix port number check on releaseJean Delvare1-1/+1
The port number shift is still hard-coded to 1 while it now depends on the hardware. Thankfully 0 is always 0 no matter how you shift it, so this was a bug without consequences. Signed-off-by: Jean Delvare <jdelvare@suse.de> Fixes: 0fe16195f891 ("i2c: piix4: Fix SMBus port selection for AMD Family 17h chips") Reviewed-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-12i2c: stm32: Fix copyrightsBenjamin Gaignard3-3/+6
Uniformize STMicroelectronics copyrights headers and add SPDX identifier. Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com> Acked-by: Alexandre TORGUE <alexandre.torgue@st.com> Acked-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Acked-by: M'boumba Cedric Madianga <cedric.madianga@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-07i2c: imx: use proper GPIO directions for recoveryWolfram Sang1-2/+2
When converting to GPIOD, the GPIO directions of SCL/SDA have been swapped. Fix it! Fixes: ad36a27959cabb ("i2c: imx: switch to using gpiod for bus recovery gpios") Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-07i2c-cht-wc: constify platform_device_idArvind Yadav1-1/+1
platform_device_id are not supposed to change at runtime. All functions working with platform_device_id provided by <linux/platform_device.h> work with const platform_device_id. So mark the non-const structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Reviewed-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03i2c: rcar: skip DMA if buffer is not safeWolfram Sang1-1/+1
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>
2017-12-03i2c: sh_mobile: use core helper to decide when to use DMAWolfram Sang1-2/+6
This ensures that we fall back to PIO if the message length is too small for DMA being useful. Otherwise, we use DMA. A bounce buffer might be applied by the helper if the original message buffer is not DMA safe. 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>
2017-12-03i2c: smbus: use DMA safe buffers for emulated SMBus transactionsWolfram Sang1-6/+39
For all block commands, try to allocate a DMA safe buffer and mark it accordingly. Only use the stack, if the buffers cannot be allocated. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03i2c: refactor i2c_master_{send_recv}Wolfram Sang1-46/+18
Those two functions are very similar, the only differences are that one needs the I2C_M_RD flag for its message while the other one needs the buffer casted to drop the const. Introduce a generic helper which allows to specify the flags (also needed later for DMA safe variants of these calls) and let the casting be done in the inlining functions which are now calling the new helper function. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-12-03i2c: dev: mark RDWR buffers as DMA_SAFEWolfram Sang1-0/+2
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>
2017-12-03i2c: add helpers to ease DMA handlingWolfram Sang1-0/+46
One helper checks if DMA is suitable and optionally creates a bounce buffer, if not. The other function returns the bounce buffer and makes sure the data is properly copied back to the message. 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>
2017-12-03i2c: gpio: add fault injectorWolfram Sang2-0/+119
Add fault injection capabilities to the i2c-gpio driver. When connected to another I2C bus, it can create unusual states which the other I2C bus master driver needs to handle. Only for debugging! Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2017-11-28i2c: designware: fix building driver as modulePhil Reid1-0/+1
The designware core and platform are built as separate modules. Export i2c_dw_prepare_clk() so it can be used by the platform driver. Fixes: a34a0b6da22540d19e57 ("i2c: designware: move i2c_dw_plat_prepare_clk to common") Signed-off-by: Phil Reid <preid@electromag.com.au> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-28i2c: core: fix compile issue related to incorrect gpio headerPhil Reid1-1/+1
The correct header to include for the gpiod interface is <linux/gpio/consumer.h>. Fixes: 3991c5c80beaf7eb9 ("i2c: Switch to using gpiod interface for gpio bus recovery") Signed-off-by: Phil Reid <preid@electromag.com.au> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: i2c-boardinfo: fix memory leaks on devinfoColin Ian King1-0/+2
Currently when an error occurs devinfo is still allocated but is unused when the error exit paths break out of the for-loop. Fix this by kfree'ing devinfo to avoid the leak. Detected by CoverityScan, CID#1416590 ("Resource Leak") Fixes: 4124c4eba402 ("i2c: allow attaching IRQ resources to i2c_board_info") Fixes: 0daaf99d8424 ("i2c: copy device properties when using i2c_register_board_info()") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: i801: Fix Failed to allocate irq -2147483648 errorHans de Goede1-0/+3
On Apollo Lake devices the BIOS does not set up IRQ routing for the i801 SMBUS controller IRQ, so we end up with dev->irq set to IRQ_NOTCONNECTED. Detect this and do not try to use the irq in this case silencing: i801_smbus 0000:00:1f.1: Failed to allocate irq -2147483648: -107 Cc: stable@vger.kernel.org BugLink: https://communities.intel.com/thread/114759 Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: make sure to not accidently trigger STOPWolfram Sang1-3/+3
The datasheet was a bit vague, but after consultation with HW designers, we came to the conclusion that we should set the SCP bit always when dealing only with the ICE bit. A set SCP bit is ignored, and thus fine, a cleared one may trigger STOP on the bus. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: send STOP according to datasheetWolfram Sang1-23/+6
We initiate STOP (or REP_START) on the second last WAIT interrupt currently. This works fine but is not according to the datasheet which says to do it on the last WAIT interrupt. This also simplifies the code quite a lot, so let's do it. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: avoid unnecessary register readWolfram Sang1-1/+2
There is no data when the first WAIT interrupt arrives. No need to read something then. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: let RuntimePM do the clock handlingWolfram Sang1-2/+0
No need to do it manually. Reported-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Tested-by: Jacopo Mondi <jacopo+renesas@jmondi.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: shorten exit of xfer routineWolfram Sang1-3/+1
We can use the ternary operator for easier reading. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: use direct writes when accessing ICE bitWolfram Sang1-3/+3
ICE bit is for resetting the module. Other bits don't matter then, so we don't need to use the iic_set_clr() function but can use iic_wr(). Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: manually "inline" two short functionsWolfram Sang1-19/+9
Those two functions are very short and only called once. The code becomes easier to understand if the code is directly put into the main xfer function. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: remove redundant deinitializationWolfram Sang1-4/+0
No need to clear the interrupt registers because right after that we disable the IP core which will reload registers with their initial values anyhow. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: sh_mobile: remove redundant initializationWolfram Sang1-10/+0
Following the documentation, we initialize the HW before each START in start_ch(). No need to do the same in activate_ch(). Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: remove legacy integer scl/sda gpio for recoveryPhil Reid1-76/+2
Remove all reference to code related to using integer based ids for scl/sda gpio for bus recovery. All in tree drivers are now using the gpio descriptors to specific the required gpios. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Phil Reid <preid@electromag.com.au> Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: davinci: switch to using gpiod for bus recovery gpiosPhil Reid1-5/+15
Change the driver to use the gpio descriptors for the bus recovery information instead of the deprecated integer interface. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Phil Reid <preid@electromag.com.au> Reviewed-by: Sekhar Nori <nsekhar@ti.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: imx: switch to using gpiod for bus recovery gpiosPhil Reid1-9/+9
Change the driver to use the gpio descriptors for the bus recovery information instead of the deprecated integer interface. Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-11-27i2c: designware: add i2c gpio recovery optionTim Sander3-1/+63
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>
2017-11-27i2c: designware: rename i2c_dw_plat_prepare_clk to i2c_dw_prepare_clkPhil Reid3-9/+9
For consistency with the rest of the file rename function and parameter to be consistent with the reset of the common file. Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

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