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| * | i2c: rk3x: Fix sparse warningDavid Wu2016-09-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes the following sparse warning: drivers/i2c/busses/i2c-rk3x.c:888:17: warning: cast truncates bits from constant value (ffffffffff00 becomes ffffff00) Reported-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: David Wu <david.wu@rock-chips.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c / ACPI: Do not touch an I2C device if it belongs to another adapterMika Westerberg2016-09-22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When enumerating I2C devices connected to an I2C adapter we scan the whole namespace (as it is possible to have devices anywhere in that namespace, not just below the I2C adapter device) and add each found device to the I2C bus in question. Now after commit 525e6fabeae2 ("i2c / ACPI: add support for ACPI reconfigure notifications") checking of the adapter handle to the one found in the I2cSerialBus() resource was moved to happen after resources of the I2C device has been parsed. This means that if the I2cSerialBus() resource points to an adapter that does not exists in the system we still parse those resources. This is problematic in particular because acpi_dev_resource_interrupt() tries to configure GSI if the device also has an Interrupt() resource. Failing to do that results errrors like this to be printed on the console: [ 10.409490] ERROR: Unable to locate IOAPIC for GSI 37 To fix this we pass the I2C adapter to i2c_acpi_get_info() and make sure the handle matches the one in the I2cSerialBus() resource before doing anything else to the device. Reported-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Nicolai Stange <nicstange@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: octeon: Fix high-level controller status checkJan Glauber2016-09-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In case the high-level controller (HLC) is used the status code is reported at a different location. Check that location after HLC write operations if the ready bit is not set and return an appropriate error code instead of always returning -EAGAIN. Signed-off-by: Jan Glauber <jglauber@cavium.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: octeon: Avoid sending STOP during recoveryDmitry Bazhenov2016-09-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Due to a bug in the ThunderX I2C hardware sending STOP during a recovery attempt could lock up the hardware. To work around this problem do not send STOP at the beginning of the recovery but use the override registers to bring the TWSI including the high-level controller out of the bad state. Signed-off-by: Dmitry Bazhenov <dmitry.bazhenov@auriga.com> Signed-off-by: Jan Glauber <jglauber@cavium.com> [Changed commit message] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: octeon: Fix set SCL recovery functionDmitry Bazhenov2016-09-21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The set SCL recovery function unconditionally pulls the SCL line low. Only pull SCL line low according to val parameter. Signed-off-by: Dmitry Bazhenov <dmitry.bazhenov@auriga.com> Signed-off-by: Jan Glauber <jglauber@cavium.com> [Changed commit message] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: rcar: add support for r8a7796 (R-Car M3-W)Ulrich Hecht2016-09-16
| | | | | | | | | | | | | | | | | | | | | Same as r8a7795. Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: imx: make bus recovery through pinctrl optionalYang Li2016-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit 1c4b6c3bcf30 ("i2c: imx: implement bus recovery") the driver starts to use gpio/pinctrl to support optional bus recovery feature. But pinctrl is not always usable. There are platforms such as ls1021a and ls1043a that don't support pinctrl, and it could just be broken due to old/broken device tree. The patch makes it really optional that the probe function won't bailout on pinctrl problems instead it just disables bus recovery and prints out notification when there is problem with pinctrl. Since pinctrl is only used by bus recovery in this driver, move pinctrl initialization into bus recovery init function to prevent confusion. Signed-off-by: Li Yang <leoyang.li@nxp.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: meson: add gxbb compatible stringNeil Armstrong2016-09-15
| | | | | | | | | | | | | | | | | | | | | Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Acked-by: Kevin Hilman <khilman@baylibre.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: uniphier-f: set the adapter to master mode when probingMasahiro Yamada2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the adapter is set to the master mode at the first use. Since then, it is kept in the slave mode, so unexpected glitch signals on the I2C lines may cause the adapter into insane state. Setting it to the master mode along with initialization solves the problem. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reported-by: Akio Noda <noda.akio@socionext.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: uniphier-f: avoid WARN_ON() of clk_disable() in failure pathMasahiro Yamada2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If clk_prepare_enable() fails, clk_disable_unprepare() is called in the failure path, where the enable_count is still zero, so it hits WARN_ON(core->enable_count == 0) in the clk_core_disable(). To fix this, make the clock setting more linear in the probe function so that it can exploit "goto err" in case of error. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: uniphier: avoid WARN_ON() of clk_disable() in failure pathMasahiro Yamada2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If clk_prepare_enable() fails, clk_disable_unprepare() is called in the failure path, where the enable_count is still zero, so it hits WARN_ON(core->enable_count == 0) in the clk_core_disable(). To fix this, make the clock setting more linear in the probe function so that it can exploit "goto err" in case of error. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Fix assignment of boolean variablesJon Hunter2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the following warnings reported by coccinelle for the Tegra I2C driver. drivers/i2c/busses/i2c-tegra.c:513:2-23: WARNING: Assignment of bool to 0/1 drivers/i2c/busses/i2c-tegra.c:539:3-24: WARNING: Assignment of bool to 0/1 Reported-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: proper handling of error casesShardar Shariff Md2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To summarize the issue observed in error cases: SW Flow: For i2c message transfer, packet header and data payload is posted and then required error/packet completion interrupts are enabled later. HW flow: HW process the packet just after packet header is posted, if ARB lost/NACK error occurs (SW will not handle immediately when error happens as error interrupts are not enabled at this point). HW assumes error is acknowledged and clears current data in FIFO, But SW here posts the remaining data payload which still stays in FIFO as stale data (data without packet header). Now once the interrupts are enabled, SW handles ARB lost/NACK error by clearing the ARB lost/NACK interrupt. Now HW assumes that SW attended the error and will parse/process stale data (data without packet header) present in FIFO which causes invalid NACK errors. Fix: Enable the error interrupts before posting the packet into FIFO which make sure HW to not clear the fifo. Also disable the packet mode before acknowledging errors (ARB lost/NACK error) to not process any stale data. As error interrupts are enabled before posting the packet header use spinlock to avoid preempting. Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: use atomic poll function during configurationShardar Shariff Md2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | Use readl_poll_timeout_atomic() function as *wait_for_config_load() function can be called from interrupt context. Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: add separate function for config_load programingShardar Shariff Md2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | Define separate function for configuration load register handling to make it use by different functions later. Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: If fifo flush fails return errorShardar Shariff Md2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | During i2c controller initialization, when fifo flush fails return error instead of returning the error during exit. Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: use readl_poll_timeout after config_load reg programmedShardar Shariff Md2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | After CONFIG_LOAD register is programmed instead of explicitly waiting for timeout, use readl_poll_timeout() to check for register value to get updated or wait till timeout. Signed-off-by: Shardar Shariff Md <smohammed@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: shmobile: Use ARCH_SHMOBILE instead of SUPERHGeert Uytterhoeven2016-09-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "i2c-sh_mobile" is used on sh7343, sh7366, sh7722, sh7723, and sh7724 only. As all of the above select ARCH_SHMOBILE, restrict its driver dependencies from SUPERH to ARCH_SHMOBILE. Signed-off-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>
| * | i2c: core: put literals on one line in dev_*() callsAndy Shevchenko2016-08-30
| | | | | | | | | | | | | | | | | | | | | It's better to have strings in the code like they appeared in the output. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: move locking operations to their own structPeter Rosin2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | This makes it trivial to constify them, so do that. Signed-off-by: Peter Rosin <peda@axentia.se> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Add pinctrl supportJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | On Tegra124/132 the pins for I2C6 are shared with the Display Port AUX (DPAUX) channel and on Tegra210 the pins for I2C4 and I2C6 are shared with DPAUX1 and DPAUX0, respectively. The multiplexing of the pins is handled by a register in the DPAUX and so the Tegra DPAUX driver has been updated to register a pinctrl device for managing these pins. The pins for these particular I2C devices are bound to the I2C device prior to probing. However, these I2C devices are in a different power partition to the DPAUX devices that own the pins. Hence, it is desirable to place the pins in the 'idle' state and allow the DPAUX power partition to switch off, when these I2C devices is not in use. Therefore, add calls to place the I2C pins in the 'default' and 'idle' states when the I2C device is runtime resumed and suspended, respectively. Please note that the pinctrl functions that set the state of the pins check to see if the devices has pins associated and will return zero if they do not. Therefore, it is safe to call these pinctrl functions even for I2C devices that do not have any pins associated. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Add runtime power-management supportJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update the Tegra I2C driver to use runtime PM and move the code in the tegra_i2c_clock_enable/disable() functions to the PM runtime resume and suspend callbacks, respectively. Note that given that CONFIG_PM is not mandatory for Tegra, if CONFIG_PM is not enabled and so runtime PM is not enabled, ensure that the I2C clocks are turned on during probe and kept on by calling the resume callback directly. In the function tegra_i2c_init(), the variable 'err' does not need to be initialised to zero in tegra_i2c_init() because it is initialised when pm_runtime_get_sync() is called. Furthermore, to ensure we only return 0 from tegra_i2c_init(), it is necessary to re-initialise 'err' to 0 after a successful call to pm_runtime_get_sync() because it can return a positive value on success. However, alternatively re-initialise 'err' by using the return value of the function tegra_i2c_flush_fifos() because it can only be 0 or -ETIMEDOUT. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Simplify I2C resumeJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The I2C adapter is unlocked regardless of whether the tegra_i2c_init() called during the resume is successful or not. However, if the tegra_i2c_init() is not successful, then ->is_suspended is not set to false. Simplify the resume code by only setting ->is_suspended to false if tegra_i2c_init() is successful and return the error code from tegra_i2c_init(). Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Use device name for adapter nameJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All Tegra I2C devices have the name "Tegra I2C adapter" which is not very useful when viewing the I2C adapter names via the sysfs. Therefore, use the device name, which is unique for each I2C device, instead. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Remove non device-tree supportJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | Tegra has only supported device-tree for platform/board configuration for quite some time now and so simplify the Tegra I2C driver by dropping code for non device-tree platforms/boards. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Add missing new line charactersJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | Add missing new line characters for the various error messages. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Acked-by: Laxman Dewangan <ldewangan@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Fix missing blank lines after declarationsJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Checkpatch warns about missing blank lines after declarations in the Tegra I2C driver and so fix these. Note that the initialisation of 'val' to zero in tegra_dvc_init() is unnecessary and so remove this. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Use BIT macroJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | Checkpatch warns about spacing around the '<<' operator in the Tegra I2C driver and so fix these by converting the bit definitions that are using this operator to use the BIT macro. Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | i2c: tegra: Fix lines over 80 charactersJon Hunter2016-08-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Checkpatch warns about some lines over 80 characters in the Tegra I2C driver and so fix these. While we are at it, prefix the second instance of "STOP condition" in the comment with a "the". Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | Merge branch 'i2c-mux-dt-3' of https://github.com/peda-r/i2c-mux into ↵Wolfram Sang2016-08-25
| |\ \ | | | | | | | | | | | | | | | | | | | | i2c/for-4.9 Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| | * | i2c: pca954x: add device tree bindingPeter Rosin2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No longer rely on the implicit matching with the i2c device name, use an explicit compatible string instead. Keep a direct pointer to the chip description instead of an index into the chip description array. Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Peter Rosin <peda@axentia.se>
| | * | i2c: pca9541: add device tree bindingPeter Rosin2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | No longer rely on the implicit matching with the i2c device name, use an explicit compatible string instead. Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Peter Rosin <peda@axentia.se>
| | * | i2c: mux: inform the i2c mux core about how it is usedPeter Rosin2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The i2c mux core can then take appropriate action depending on if it is used for an actual i2c mux, for a gate or for an arbitrator (the last is the case for these drivers). This adds support for the new clearer and more compact devicetree bindings that was added recently. Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Peter Rosin <peda@axentia.se>
| | * | i2c: mux: add support for 'i2c-mux', 'i2c-arb' and 'i2c-gate' DT subnodesPeter Rosin2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Backwards compatibility is preserved; the subnodes are in practice optional. However, the mux core needs to know what subnode it should examine, so add a couple of new flags for i2c_mux_alloc for this purpose. The rule is that if the mux core finds a 'reg' property in the appropriate subnode, e.g. if 'reg' exists in the 'i2c-mux' subnode, then the mux core will assume that this is an old style entry and not an i2c-mux subnode (correspondingly for arbitrators and gates with 'i2c-arb' and 'i2c-gate'). Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Peter Rosin <peda@axentia.se>
| * | | i2c: designware: do not disable adapter after transferLucas De Marchi2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Disabling the adapter after each transfer adds additional delays for each I2C transfer. Even if we don't wait for it to be disabled anymore, on next transfer we will need to if we have several transfers in a row. Now during the transfer init we check if IC_TAR can be changed dynamically, the status register for no activity and TX buffer being empty. In this case we don't need to disable it When a transfer fails the adapter will still be disabled - this is a conservative approach. When transfers succeed, the adapter is left enabled and it's configured so to disable interrupts. Alternating register reads on 2 slaves: perf stat -r4 chrt -f 10 ./i2c-test /dev/i2c-1 25000 0x40 0x6 0x1e 0x00 Before: 8.638705161 seconds time elapsed ( +- 5.90% ) After: 7.516821591 seconds time elapsed ( +- 0.11% ) Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Signed-off-by: José Roberto de Souza <jose.souza@intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Christian Ruppert <christian.ruppert@alitech.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | | i2c: designware: detect when dynamic tar update is possibleLucas De Marchi2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adapter can be synthesized with dynamic tar update enabled or disabled. When enabled it is not necessary to disable the adapter to change the slave address in some situations, which saves some time per transaction. There is no direct register to know if this feature is enabled but we can do it indirectly by writing to the 10BIT_ADDR field in IC_CON: this field is read only when dynamic tar update is enabled. Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Signed-off-by: José Roberto de Souza <jose.souza@intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Christian Ruppert <christian.ruppert@alitech.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | | i2c: designware: add common functions for lockingLucas De Marchi2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These are used in 2 places and will be needed in more. Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Christian Ruppert <christian.ruppert@alitech.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | | i2c: designware: wait for disable/enable only if necessaryJosé Roberto de Souza2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we aren't going to continue using the controller we can just disable it instead of waiting for it to complete. The biggest improvement here is when a I2C transaction is completed and it doesn't block until the adapter is disabled. When a new transfer is needed we will disable and wait for its completion. This way the adapter will continue changing its state in parallel to the execution of the thread that requested the I2C transaction saving most of the time 25~250 usec per I2C transaction. A simple program doing a register read (1 byte write, 1 byte read) alternating on 2 different slaves repeated 25k times for each and measurements taken 4 times we get: perf stat -r4 chrt -f 10 ./i2c-test /dev/i2c-1 25000 0x40 0x6 0x1e 0x00 Before: 30.879317977 seconds time elapsed ( +- 14.83% ) After: 8.638705161 seconds time elapsed ( +- 5.90% ) Signed-off-by: José Roberto de Souza <jose.souza@intel.com> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Tested-by: Christian Ruppert <christian.ruppert@alitech.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | | i2c: designware: Find bus speed from ACPIJarkko Nikula2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fast mode is the default speed of i2c-designware which can be overridden by platform data or by "clock-frequency" device property. Even though the ACPI 5.1 can pass device properties via _DSD method, shipping systems define the connection speed between I2C host and each slave in their I2cSerialBus resources. Which means speed is not defined per bus but per slave. As there is now support in i2c-core to find the bus speed from ACPI use that to set up the bus speed prior registering the I2C adapter. Signed-off-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>
| * | | i2c: core: Add function for finding the bus speed from ACPI, take 2Jarkko Nikula2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ACPI 5 specification doesn't have property for the I2C bus speed but I2cSerialBus resource descriptor which define each controller-slave connection define the maximum speed supported by that connection. Thus finding the maximum safe speed for the bus is to walk through all I2cSerialBus resources that are associated to I2C controller and use the speed of slowest connection. Add function i2c_acpi_find_bus_speed() to the i2c-core that adapter drivers can call prior registering itself to core. This implies two-step walk through the I2cSerialBus resources: call to i2c_acpi_find_bus_speed() does the first scan and finds the safe bus speed that adapter drivers can set up. Adapter driver registration does the second scan when i2c-core creates the I2C slaves by calling the i2c_acpi_register_devices(). In that way the bus speed is set in case slave device probe gets called during registration and does communication. Previous version commit 55d38d060e99 ("i2c: core: Add function for finding the bus speed from ACPI") got reverted due merge conflicts from commit 525e6fabeae2 ("i2c / ACPI: add support for ACPI reconfigure notifications"). This version is a bit bigger than previous version but is still sharing the lowest and complicated part of I2cSerialBus lookup routines with the existing code. Signed-off-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>
| * | | i2c: core: Cleanup I2C ACPI namespace, take 2Jarkko Nikula2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I2C ACPI enumeration was originally implemented in another module under drivers/acpi/ but was later moved into i2c-core with added support for I2C ACPI operation region. Rename these acpi_i2c_ prefixed functions, structures and defines in i2c-core to i2c_acpi_ in order to have more consistent name space. This is updated version from commit a7003b65801e ("i2c: core: Cleanup I2C ACPI namespace") that got reverted due merge conflicts from commit 525e6fabeae2 ("i2c / ACPI: add support for ACPI reconfigure notifications"). Signed-off-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>
| * | | i2c: designware: Enable high speed modeWeifeng Voon2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch enabled high speed mode. High speed mode can be turn on by setting the clk_freq to 3400000. High speed HCNT and LCNT are needed as there is no default value provided. Signed-off-by: Weifeng Voon <weifeng.voon@intel.com> Signed-off-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>
| * | | i2c: designware: set the common config before the if elseWeifeng Voon2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | DW_IC_CON_MASTER, DW_IC_CON_SLAVE_DISABLE and DW_IC_CON_RESTART_EN are common config that need to be set for i2c designware master. So, configure it first without having to repeat inside the if else. Signed-off-by: Weifeng Voon <weifeng.voon@intel.com> Signed-off-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>
| * | | i2c: designware: Enable fast mode plusWeifeng Voon2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch enabled fast mode plus. The fast mode plus and fast speed share the same HCNT and LCNT register. So, the fast mode plus will only run when the HCNT and LCNT value is provided. Else, it will run at fast speed as default. Signed-off-by: Weifeng Voon <weifeng.voon@intel.com> Signed-off-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>
| * | | i2c: designware: get fast plus and high speed *CNT configurationWeifeng Voon2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I2C designware controller can run at fast mode plus and high speed. This patch adds the capability to get the HCNT, LCNT configuration via FPCN (fast plus) and HSCN (high speed) ACPI method. Signed-off-by: Weifeng Voon <weifeng.voon@intel.com> Signed-off-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>
| * | | i2c: designware: Move clk_freq into struct dw_i2c_devWeifeng Voon2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I2c designware controller operate speed is configured in the register IC_CON. Previously the operate speed is determined by a local variable clk_freq. This patch will move the local variable clk_freq into struct dw_i2c_dev. This change will ease the set and get of the clk_freq. Signed-off-by: Weifeng Voon <weifeng.voon@intel.com> Signed-off-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>
| * | | i2c: octeon: Use booleon values for booleon variablesJan Glauber2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Initialize booleon values with true instead of 1. Signed-off-by: Jan Glauber <jglauber@cavium.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | | i2c: octeon: Sort include files alphabeticallyJan Glauber2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sort include files alphabetically to reduce probability of merge conflicts. Signed-off-by: Jan Glauber <jglauber@cavium.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | | i2c: octeon,thunderx: Move register offsets to structJan Glauber2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The register offsets are different between Octeon and ThunderX so move them into the algorithm struct and get rid of the define. Signed-off-by: Jan Glauber <jglauber@cavium.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
| * | | i2c: thunderx: Add SMBUS alert supportJan Glauber2016-08-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add SMBUS alert interrupt support. For now only device tree is supported for specifying the alert. In case of ACPI an error is returned. Signed-off-by: Jan Glauber <jglauber@cavium.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
generated by cgit v1.2.2 (git 2.25.0) at 2025-08-04 13:29:07 -0400