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path: root/drivers/i2c/busses/i2c-designware-core.h
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2015-12-12i2c: designware: fix IO timeout issue for AMD controllerXiangliang Yu
Because of some hardware limitation, AMD I2C controller can't trigger pending interrupt if interrupt status has been changed after clearing interrupt status bits. Then, I2C will lost interrupt and IO timeout. According to hardware design, this patch implements a workaround to disable i2c controller interrupt and re-enable i2c interrupt before exiting ISR. To reduce the performance impacts on other vendors, use unlikely function to check flag in ISR. Signed-off-by: Xiangliang Yu <Xiangliang.Yu@amd.com> Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2015-10-15i2c: designware: Move common probe code into i2c_dw_probe()Jarkko Nikula
There is some code duplication in i2c-designware-platdrv and i2c-designware-pcidrv probe functions. What is even worse that duplication requires i2c_dw_xfer(), i2c_dw_func() and i2c_dw_isr() i2c-designware-core functions to be exported. Therefore move common code into new i2c_dw_probe() and make functions above local to i2c-designware-core. While merging the code patch does following functional changes: - I2C Adapter name will be "Synopsys DesignWare I2C adapter". Previously it was used for platform and ACPI devices but PCI device used "i2c-designware-pci". - Using device name for interrupt name. Previous it was platform device name, ACPI device name or "i2c-designware-pci". - Error code from devm_request_irq() and i2c_add_numbered_adapter() will be printed in case of error. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-15i2c: designware: Make dw_readl() and dw_writel() staticJarkko Nikula
dw_readl() and dw_writel() are not used outside of i2c-designware-core and they are not exported so make them static and remove their forward declaration. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-15i2c: designware: Remove unused functionsJarkko Nikula
i2c_dw_is_enabled() became unused by the commit be58eda775c8 ("i2c: designware-pci: Cleanup driver power management") and i2c_dw_enable() by the commit 3a48d1c08fe0 ("i2c: prevent spurious interrupt on Designware controllers"). Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-10-15i2c: designware: Remove interrupt clearing from i2c_dw_pci_probe()Jarkko Nikula
There is no need to clear interrupts in i2c_dw_pci_probe() since only place where interrupts are unmasked is i2c_dw_xfer_init() and there interrupts are always cleared after commit 2a2d95e9d6d2 ("i2c: designware: always clear interrupts before enabling them"). This allows to cleanup the code and replace i2c_dw_clear_int() in i2c_dw_xfer_init() by direct register read as there are no other callers. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-26i2c: designware: Add Intel Baytrail PMIC I2C bus supportDavid Box
This patch implements an I2C bus sharing mechanism between the host and platform hardware on select Intel BayTrail SoC platforms using the X-Powers AXP288 PMIC. On these platforms access to the PMIC must be shared with platform hardware. The hardware unit assumes full control of the I2C bus and the host must request access through a special semaphore. Hardware control of the bus also makes it necessary to disable runtime pm to avoid interfering with hardware transactions. Signed-off-by: David E. Box <david.e.box@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-26i2c: designware: Add i2c bus locking supportDavid Box
Adds support for acquiring and releasing a hardware bus lock in the i2c designware core transfer function. This is needed for i2c bus controllers that are shared with but not controlled by the kernel. Signed-off-by: David E. Box <david.e.box@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2014-11-07i2c: remove FSF addressWolfram Sang
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>
2014-03-09i2c: designware: make SCL and SDA falling time configurableRomain Baeriswyl
This patch allows to set independantly SCL and SDA falling times. The tLOW period is computed by taking into account the SCL falling time. The tHIGH period is computed by taking into account the SDA falling time. For instance in case the margin on tLOW is considered too small, it can be increased by increasing the SCL falling time which is by default set at 300ns. The same applies for tHIGH period with the help of SDA falling time. Signed-off-by: Romain Baeriswyl <romainba@abilis.com> Reviewed-by: Christian Ruppert <christian.ruppert@abilis.com> Acked-by: Shinya Kuribayashi <skuribay@pobox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-08-28i2c: designware: make HCNT/LCNT values configurableMika Westerberg
The DesignWare I2C controller has high count (HCNT) and low count (LCNT) registers for each of the I2C speed modes (standard and fast). These registers are programmed based on the input clock speed in the driver. The current code calculates these values based on the input clock speed and tries hard to meet the I2C bus timing requirements. This could result non-optimal values with regarding to the bus speed. For example on Intel BayTrail we get bus speed of 315.41kHz which is ~20% slower than we would expect (400kHz) in fast mode (even though the timing requirements are met). This patch makes it possible for the platform code to pass more optimal HCNT/LCNT values to the core driver if they are known beforehand. If these are not set we use the calculated and more conservative values. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Shinya Kuribayashi <skuribay@pobox.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-06-26i2c-designware: make SDA hold time configurableChristian Ruppert
This patch makes the SDA hold time configurable through device tree. Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com> Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com> Acked-by: Vineet Gupta <vgupta@synopsys.com> for arch/arc bits Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2013-05-17i2c: designware: fix RX FIFO overrunJosef Ahmad
i2c_dw_xfer_msg() pushes a number of bytes to transmit/receive to/from the bus into the TX FIFO. For master-rx transactions, the maximum amount of data that can be received is calculated depending solely on TX and RX FIFO load. This is racy - TX FIFO may contain master-rx data yet to be processed, which will eventually land into the RX FIFO. This data is not taken into account and the function may request more data than the controller is actually capable of storing. This patch ensures the driver takes into account the outstanding master-rx data in TX FIFO to prevent RX FIFO overrun. Signed-off-by: Josef Ahmad <josef.ahmad@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
2012-05-12i2c: designware: Add support for 16bit register accessStefan Roese
The STM SPEAr platform can only access the i2c controller register via 16bit read/write functions. This patch adds support to automatically detect this 16bit access mode. Signed-off-by: Stefan Roese <sr@denx.de> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2011-10-29i2c-designware: Add runtime power management supportDirk Brandewie
Add runtime power management to the PCI driver. Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-10-29i2c-designware: Add support for Designware core behind PCI devices.Dirk Brandewie
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-10-29i2c-designware: Push all register reads/writes into the core code.Dirk Brandewie
Move all register manipulation code into the core, also move register offset definitions to i2c-designware-core.c since the bus specific portions of the driver no longer need/use them. Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-10-29i2c-designware: move controller config to bus specific portion of driverDirk Brandewie
With multiple I2C adapters possible in the system each running at (possibly) different speeds we need to move the controller configuration bit field to the adapter. Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-10-29i2c-designware: move i2c functionality bit field to be adapter specificDirk Brandewie
The functionality of the adapter depends on the configuration of the IP block at silicon compile time and is adapter specific. Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-10-29i2c-designware: Move retriveving the clock speed out of core code.Dirk Brandewie
The clock frequecy supplied to the IP core is specific to a single instance of the driver. This patch makes it possible to have multiple Designware I2C cores in the system possibly running at different core frequencies. Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-10-29i2c-designware: split of i2c-designware.c into core and bus specific partsDirk Brandewie
This patch splits i2c-designware.c into three pieces: i2c-designware-core.c, contains the code that interacts directly with the core. i2c-designware-platdrv.c, contains the code specific to the platform driver using the core. i2c-designware-core.h contains the definitions and declareations shared by i2c-designware-core.c and i2c-designware-platdrv.c. This patch is the first in a set to allow multiple instances of the designware I2C core in the system. Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>