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path: root/drivers/i2c/busses/i2c-designware-core.c
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* i2c: designware: always clear interrupts before enabling themMika Westerberg2013-05-17
| | | | | | | | | | | | | | | If the I2C bus is put to a low power state by an ACPI method it might pull the SDA line low (as its power is removed). Once the bus is put to full power state again, the SDA line is pulled back to high. This transition looks like a STOP condition from the controller point-of-view which sets STOP detected bit in its status register causing the driver to fail subsequent transfers. Fix this by always clearing all interrupts before we start a transfer. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org
* i2c: designware: fix RX FIFO overrunJosef Ahmad2013-05-17
| | | | | | | | | | | | | | | | | | | | 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
* i2c-designware: switch to use runtime PM autosuspendMika Westerberg2013-04-15
| | | | | | | | | | Using autosuspend helps to reduce the resume latency in situations where another I2C message is going to be started soon. For example with HID over I2C touch panels we get several messages in a short period of time while the touch panel is in use. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c-designware: use usleep_range() in the busy-loopMika Westerberg2013-04-15
| | | | | | | | This is not an atomic context so there is no need to use mdelay() but instead use usleep_range(). Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c-designware: enable/disable the controller properlyMika Westerberg2013-04-15
| | | | | | | | | | | | The correct way to disable or enable the controller is to wait until the DW_IC_ENABLE_STATUS register bit matches the bit we program into DW_IC_ENABLE register. This procedure is described in the DesignWare I2C databook. By doing this we can be sure that the controller is in correct state once the function returns. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c-designware: always set the STOP bit after last byteMika Westerberg2013-01-27
| | | | | | | | | | | | | | | | If IC_EMPTYFIFO_HOLD_MASTER_EN is set to one, the DesignWare I2C controller doesn't generate STOP on the bus when the FIFO is empty. This violates the rules of Linux I2C stack as it requires that the STOP is issued once the i2c_transfer() is finished. However, there is no way to detect this from the hardware registers, so we must make sure that the STOP bit is always set once the last byte of the last message is transferred. This patch is based on the work of Dirk Brandewie. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c-designware: add missing MODULE_LICENSEMika Westerberg2013-01-22
| | | | | | | | The driver can also be built as a module so add MODULE_LICENSE for it. In addition add MODULE_DESCRIPTION as well. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
* i2c-designware: i2c_dw_xfer_msg can be staticJean Delvare2012-10-05
| | | | | | | | | i2c_dw_xfer_msg is only called internally so it can be static. It original was, before the driver split. No idea why it was changed at that time. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Dirk Brandewie <dirk.brandewie@gmail.com>
* i2c-designware: Fix build error if CONFIG_I2C_DESIGNWARE_PLATFORM=y && ↵Axel Lin2012-09-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | CONFIG_I2C_DESIGNWARE_PCI=y This patch adds config I2C_DESIGNWARE_CORE in Kconfig, and let I2C_DESIGNWARE_PLATFORM and I2C_DESIGNWARE_PCI select I2C_DESIGNWARE_CORE. Because both I2C_DESIGNWARE_PLATFORM and I2C_DESIGNWARE_PCI can be built as built-in or module, we also need to export the functions in i2c-designware-core. This fixes below build error when CONFIG_I2C_DESIGNWARE_PLATFORM=y && CONFIG_I2C_DESIGNWARE_PCI=y: LD drivers/i2c/busses/built-in.o drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_clear_int': i2c-designware-core.c:(.text+0xa10): multiple definition of `i2c_dw_clear_int' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x928): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_init': i2c-designware-core.c:(.text+0x178): multiple definition of `i2c_dw_init' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x90): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `dw_readl': i2c-designware-core.c:(.text+0xe8): multiple definition of `dw_readl' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x0): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_isr': i2c-designware-core.c:(.text+0x724): multiple definition of `i2c_dw_isr' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x63c): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_xfer': i2c-designware-core.c:(.text+0x4b0): multiple definition of `i2c_dw_xfer' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x3c8): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_is_enabled': i2c-designware-core.c:(.text+0x9d4): multiple definition of `i2c_dw_is_enabled' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x8ec): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `dw_writel': i2c-designware-core.c:(.text+0x124): multiple definition of `dw_writel' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x3c): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_xfer_msg': i2c-designware-core.c:(.text+0x2e8): multiple definition of `i2c_dw_xfer_msg' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x200): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_enable': i2c-designware-core.c:(.text+0x9c8): multiple definition of `i2c_dw_enable' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x8e0): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_read_comp_param': i2c-designware-core.c:(.text+0xa24): multiple definition of `i2c_dw_read_comp_param' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x93c): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_disable': i2c-designware-core.c:(.text+0x9dc): multiple definition of `i2c_dw_disable' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x8f4): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_func': i2c-designware-core.c:(.text+0x710): multiple definition of `i2c_dw_func' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x628): first defined here drivers/i2c/busses/i2c-designware-pci.o: In function `i2c_dw_disable_int': i2c-designware-core.c:(.text+0xa18): multiple definition of `i2c_dw_disable_int' drivers/i2c/busses/i2c-designware-platform.o:i2c-designware-platdrv.c:(.text+0x930): first defined here make[3]: *** [drivers/i2c/busses/built-in.o] Error 1 make[2]: *** [drivers/i2c/busses] Error 2 make[1]: *** [drivers/i2c] Error 2 make: *** [drivers] Error 2 Signed-off-by: Axel Lin <axel.lin@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org> Tested-by: Jiri Slaby <jslaby@suse.cz> Cc: stable@vger.kernel.org [3.2+]
* i2c: designware: Add support for 16bit register accessStefan Roese2012-05-12
| | | | | | | | | 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>
* i2c-designware: Add runtime power management supportDirk Brandewie2011-10-29
| | | | | | | 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>
* i2c-designware: Push all register reads/writes into the core code.Dirk Brandewie2011-10-29
| | | | | | | | | 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>
* i2c-designware: Support multiple cores using same ISRDirk Brandewie2011-10-29
| | | | | | | | | | Add check to make sure that the core is enabled and has outstanding interrupts. The activity bit is masked due to the fact that it will stay active even after the controller has been disabled until the contoller internal state machines have settled. Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-designware: move controller config to bus specific portion of driverDirk Brandewie2011-10-29
| | | | | | | | | 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>
* i2c-designware: move i2c functionality bit field to be adapter specificDirk Brandewie2011-10-29
| | | | | | | | 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>
* i2c-designware: Move retriveving the clock speed out of core code.Dirk Brandewie2011-10-29
| | | | | | | | | | 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>
* i2c-designware: split of i2c-designware.c into core and bus specific partsDirk Brandewie2011-10-29
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>
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