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2010-03-01Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (100 commits) ARM: Eliminate decompressor -Dstatic= PIC hack ARM: 5958/1: ARM: U300: fix inverted clk round rate ARM: 5956/1: misplaced parentheses ARM: 5955/1: ep93xx: move timer defines into core.c and document ARM: 5954/1: ep93xx: move gpio interrupt support to gpio.c ARM: 5953/1: ep93xx: fix broken build of clock.c ARM: 5952/1: ARM: MM: Add ARM_L1_CACHE_SHIFT_6 for handle inside each ARCH Kconfig ARM: 5949/1: NUC900 add gpio virtual memory map ARM: 5948/1: Enable timer0 to time4 clock support for nuc910 ARM: 5940/2: ARM: MMCI: remove custom DBG macro and printk ARM: make_coherent(): fix problems with highpte, part 2 MM: Pass a PTE pointer to update_mmu_cache() rather than the PTE itself ARM: 5945/1: ep93xx: include correct irq.h in core.c ARM: 5933/1: amba-pl011: support hardware flow control ARM: 5930/1: Add PKMAP area description to memory.txt. ARM: 5929/1: Add checks to detect overlap of memory regions. ARM: 5928/1: Change type of VMALLOC_END to unsigned long. ARM: 5927/1: Make delimiters of DMA area globally visibly. ARM: 5926/1: Add "Virtual kernel memory..." printout. ARM: 5920/1: OMAP4: Enable L2 Cache ... Fix up trivial conflict in arch/arm/mach-mx25/clock.c
2010-02-27MIPS: I2C: Add driver for Cavium OCTEON I2C ports.Rade Bozic
Signed-off-by: Rade Bozic <rade.bozic.ext@nsn.com> Signed-off-by: David Daney <ddaney@caviumnetworks.com> Cc: Michael Lawnick <michael.lawnick.ext@nsn.com> To: linux-mips@linux-mips.org To: linux-i2c@vger.kernel.org To: ben-linux@fluff.org To: khali@linux-fr.org Cc: rade.bozic.ext@nsn.com Cc: Michael Lawnick <michael.lawnick.ext@nsn.com> Patchwork: http://patchwork.linux-mips.org/patch/890/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-02-12ARM: PNX4008: use msecs_to_jiffies() rather than open-coding itRussell King
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: i2c-pnx makes no use of asm/uaccess.h nor asm/irq.hRussell King
Remove unnecessary includes Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: i2c-pnx: don't split messages across several linesRussell King
It makes them harder to grep for. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: Use i2c driver data for passing between internal functionsRussell King
Since the drivers data now contains the i2c adapter structure, we can pass around the drivers data between internal functions (which is what they want) rather than using the i2c adapter structure and having an additional pointer dereference each time. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: move i2c_adapter structure inside the drivers private dataRussell King
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: kzalloc i2c drivers internal dataRussell King
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: Make ioaddr 'void __iomem *' rather than 'u32'Russell King
This avoids unnecessary casting. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: get i2c clock rate from clk APIRussell King
Acked-by: Vitaly Wool <vitalywool@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: convert i2c-pnx to use clk API enable/disable callsRussell King
clk_set_rate() is not supposed to be used to turn clocks on and off. That's what clk_enable/clk_disable is for. Acked-by: Vitaly Wool <vitalywool@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: move i2c clock start/stop into driverRussell King
Acked-by: Vitaly Wool <vitalywool@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-12ARM: PNX4008: move i2c suspend/resume callbacks into driverRussell King
Acked-by: Vitaly Wool <vitalywool@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-02-05i2c-tiny-usb: Fix on big-endian systemsJean Delvare
The functionality bit vector is always returned as a little-endian 32-bit number by the device, so it must be byte-swapped to the host endianness. On the other hand, the delay value is handled by the USB stack, so no byte swapping is needed on our side. This fixes bug #15105: http://bugzilla.kernel.org/show_bug.cgi?id=15105 Reported-by: Jens Richter <jens@richter-stutensee.de> Signed-off-by: Jean Delvare <khali@linux-fr.org> Tested-by: Jens Richter <jens@richter-stutensee.de> Cc: Till Harbaum <till@harbaum.org> Cc: stable@kernel.org
2010-01-24i2c: imx: call ioremap only after request_mem_regionUwe Kleine-König
accordingly adapt order of release_mem_region and release_mem_region on remove. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Ben Dooks <ben-linux@fluff.org> Cc: Wolfram Sang <w.sang@pengutronix.de> Cc: Richard Zhao <linuxzsc@gmail.com> Cc: Darius Augulis <augulis.darius@gmail.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: linux-i2c@vger.kernel.org Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-01-24i2c: mxc: let time to generate stop bitValentin Longchamp
After generating the stop bit by changing MSTA from 1 to 0, the i2c_imx->stopped was immediatly set to 1. The second test on i2c_imx->stopped then is correct and the controller never waits if the bus is busy. This patch corrects this. On mx31moboard, stop bit was not generated on single write transfers. This was kept unnoticed as other transfers are made afterwards that help the write recipient to resynchronize. Thanks to Philippe and Michael for the debugging. Signed-off-by: Valentin Longchamp <valentin.longchamp@epfl.ch> Signed-off by: Philippe Rétornaz <philippe.retornaz@epfl.ch> Reported-by: Michael Bonani <michael.bonani@epfl.ch> Acked-by; Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2010-01-16i2c: Do not use device name after device_unregisterThadeu Lima de Souza Cascardo
dev_dbg outputs dev_name, which is released with device_unregister. This bug resulted in output like this: i2c Xy2�0: adapter [SMBus I801 adapter at 1880] unregistered The right output would be: i2c i2c-0: adapter [SMBus I801 adapter at 1880] unregistered Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-01-16i2c/pca: Don't use *_interruptibleWolfram Sang
Unexpected signals can disturb the bus-handling and lock it up. Don't use interruptible in 'wait_event_*' and 'wake_*' as in commits dc1972d02747d2170fb1d78d114801f5ecb27506 (for cpm), 1ab082d7cbd0f34e39a5396cc6340c00bc5d66ef (for mpc), b7af349b175af45f9d87b3bf3f0a221e1831ed39 (for omap). Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-01-16i2c-ali1563: Remove sparse warningsMárton Németh
Remove the following sparse warnings (see "make C=1"): * drivers/i2c/busses/i2c-ali1563.c:91:3: warning: do-while statement is not a compound statement * drivers/i2c/busses/i2c-ali1563.c:161:3: warning: do-while statement is not a compound statement Signed-off-by: Márton Németh <nm127@freemail.hu> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-01-16i2c: Test off by one in {piix4,vt596}_transaction()Roel Kluin
With `while (timeout++ < MAX_TIMEOUT)' timeout reaches MAX_TIMEOUT + 1 after the loop. This is probably unlikely to produce a problem. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2010-01-16i2c-core: Storage class should be before const qualifierTobias Klauser
The C99 specification states in section 6.11.5: The placement of a storage-class specifier other than at the beginning of the declaration specifiers in a declaration is an obsolescent feature. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-12-24i2c-omap: OMAP3: Fix I2C lockup during timeout/error casesManjunatha GK
Current OMAP3 I2C driver code does not follow the correct sequence for soft reset. Due to this, lock up issues are reported during timeout/error cases. This patch fixes above issue by disabling I2C controller as per OMAP3430 TRM for soft reset. As per TRM, I2C controller needs to be disabled as a first step during soft reset. Here is correct soft reset sequence: a. Ensure that the module is disabled (clear the I2Ci.I2C_CON[15] I2C_EN bit to 0). b. Set the I2Ci.I2C_SYSC[1] SRST bit to 1. c. Enable the module by setting I2Ci.I2C_CON[15] I2C_EN bit to 1. d. Check the I2Ci.I2C_SYSS[0] RDONE bit until it is set to 1 to indicate the software reset is complete. Tested on Zoom2, Zoom3, 3430SDP and 3630SDP Signed-off-by: Manjunatha GK <manjugk@ti.com> Signed-off-by: George, Harith<harith@ti.com> Acked-by: Varadarajan, Charu Latha<charu@ti.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-24i2c-omap: Don't write IE state in unidle if 0Cory Maccarrone
Commit ef871432... (i2c-omap: OMAP3: PM: (re)init for every transfer to support off-mode) introduced a change which make the dev->iestate contents be written to the OMAP_I2C_IE_REG every time omap_i2c_unidle is called. Previously, the state was only written if it wasn't equal to zero. In omap_i2c_probe, omap_i2c_unidle() is called prior to omap_i2c_init(), in which case dev->iestate has not yet been initialized and will be set to zero. Having this value written to the registers causes deadlock while booting. As such, this change restores the original functionality. Signed-off-by: Cory Maccarrone <darkstar6262@gmail.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-24i2c-bfin-twi: fix CLKDIV calculationSonic Zhang
Calculation of the CLKDIV speed setting should be done using base 10 math rather than base 2. We also avoid exceeding the spec due to integer truncation and a 50% duty cycle. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-15const: constify remaining dev_pm_opsAlexey Dobriyan
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-14i2c-core: i2c bus should support PM entries in struct dev_pm_opssonic zhang
Struct dev_pm_ops is not configured in current i2c bus type. i2c drivers only depends on suspend/resume entries in struct dev_pm_ops are not informed of PM suspend and resume events by i2c framework. Signed-off-by: Sonic Zhang <sonic.zhang@analog.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2009-12-14i2c: Get rid of struct i2c_client_address_dataJean Delvare
Struct i2c_client_address_data only contains one field at this point, which makes its usefulness questionable. Get rid of it and pass simple address lists around instead. Signed-off-by: Jean Delvare <khali@linux-fr.org> Tested-by: Wolfram Sang <w.sang@pengutronix.de>
2009-12-14i2c: Drop the kind parameter from detect callbacksJean Delvare
The "kind" parameter always has value -1, and nobody is using it any longer, so we can remove it. Signed-off-by: Jean Delvare <khali@linux-fr.org> Tested-by: Wolfram Sang <w.sang@pengutronix.de>
2009-12-09Merge branch 'acpica' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 * 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: ACPICA: Update version to 20091112. ACPICA: Add additional module-level code support ACPICA: Deploy new create integer interface where appropriate ACPICA: New internal utility function to create Integer objects ACPICA: Add repair for predefined methods that must return sorted lists ACPICA: Fix possible fault if return Package objects contain NULL elements ACPICA: Add post-order callback to acpi_walk_namespace ACPICA: Change package length error message to an info message ACPICA: Reduce severity of predefined repair messages, Warning to Info ACPICA: Update version to 20091013 ACPICA: Fix possible memory leak for Scope ASL operator ACPICA: Remove possibility of executing _REG methods twice ACPICA: Add repair for bad _MAT buffers ACPICA: Add repair for bad _BIF/_BIX packages
2009-12-09i2c-pnx: Map I2C adapter number to platform ID numberKevin Wells
Map I2C adapter number to platform ID number Signed-off-by: Kevin Wells <kevin.wells@nxp.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-omap: OMAP3: PM: (re)init for every transfer to support off-modeRajendra Nayak
Because of OMAP off-mode, powerdomain can go off when I2C is idle. Save enough state, and do a re-init for each transfer. Additional save/restore state added by Jagadeesh Bhaskar Pakaravoor (SYSC_REG) and Aaro Koskinen (wakeup sources.) Also, The OMAP3430 TRM states: "During active mode (I2Ci.I2C_CON[15] I2C_EN bit is set to 1), make no changes to the I2Ci.I2C_SCLL and I2Ci.I2C_SCLH registers. Changes may result in unpredictable behavior." Hence, the I2C_EN bit should be clearer when modifying these registers. Please note that clearing the entire I2C_CON register to disable the I2C module is safe, because the I2C_CON register is re-configured for each transfer. Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com> Signed-off-by: Rajendra Nayak <rnayak@ti.com> Cc: Jagadeesh Bhaskar Pakaravoor <j-pakaravoor@ti.com> Cc: Aaro Koskinen <aaro.koskinen@nokia.com> Cc: Jon Hunter <jon-hunter@ti.com> Cc: Hu Tao <taohu@motorola.com> Cc: Xiaolong Chen <A21785@motorola.com> Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: i2c_dw_handle_tx_abort: Use dev_dbg() for NOACK casesShinya Kuribayashi
In the case of no-ACKs, we don't want to see dev_err() messages in the console, because some utilities like i2c-tools are capable of printing decorated console output. This patch will ease such situations. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Cosmetic cleanupsShinya Kuribayashi
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Tx abort cleanupsShinya Kuribayashi
* ABRT_MASTER_DIS: Fix a typo. * i2c_dw_handle_tx_abort: Return an appropriate error number depending on abort_source. * i2c_dw_xfer: Add a missing abort_source initialization. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Skip RX_FULL and TX_EMPTY bits on tx abort errorsShinya Kuribayashi
Suppose TX_ABRT occurs in the middle of processing i2c_msg msgs[], and a STOP condition has already been generated on the bus. In this case, subsequent i2c_dw_xfer_msg() might initiate a new and unnecessary I2C transaction, which we'd have to avoid. Furthermore, anytime TX_ABRT is set, the contents of tx/rx buffers are flushed, so we don't have to process RX_FULL and TX_EMPTY. Disable interrupts, and skip them. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: i2c_dw_xfer_msg: Fix error handling proceduresShinya Kuribayashi
Current error handling procedures are not good in two respects: * Forgot to mark dev->cmd_complete as "completed" on errors Once an I2C transaction is initiated, wait_for_completion_ interruptible_timeout() waits for dev->cmd_complete to be completed. We have to take care of it whenever an error is detected, otherwise we will have a needless HZ timeout. * Forgot to disable interrupts In the previous patch, interrupt mask operations have been changed. We don't disable interrupts at the end of the interrupt handler any more, and try to keep RX_FULL (and TX_EMPTY if required) enabled during the transaction so that we can send longer data than the size of Tx/Rx FIFO. If an error is detected, we need to disable interrupts before quitting current transaction. We can work around above points using dev->msg_err effectively. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Disable TX_EMPTY when all i2c_msg msgs has been processedShinya Kuribayashi
Currently we disable TX_EMPTY interrupt when buf_len is zero, but this is wrong. (buf_len == 0) means that all transmit data in the current i2c_msg message has been sent out, but that doesn't necessarily mean all i2c_msg messages have been processed. TX_EMPTY interrupt is used as the driving force of DW I2C transactions, so we need to keep it enabled as long as i2c_msg messages are available. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Process all i2c_msg messages in the interrupt handlerShinya Kuribayashi
Currently we process the first i2c_dw_xfer_msg() in i2c_dw_xfer(), but in this case there is a possibility to be interrupted by certain interrupts. As described before in this patchset, we need to keep providing new transmit data within a given time period, otherwise Tx FIFO underrun takes place and STOP condition will be generated on the bus, even if we have more bytes to be written. In order to exclude all such possibilities, change TX_EMPTY interrupt usage as below: * DW_IC_INTR_DEFAULT_MASK: Define a default interrupt mask set, and put TX_EMPTY there. * i2c_dw_xfer_init: Enable DW_IC_INTR_DEFAULT_MASK prior to initiating a new I2C transaction. The first TX_EMPTY will be triggered shortly. With the help of it, we can make the first call to i2c_dw_xfer_msg() in the interrupt handler. * i2c_dw_xfer_msg: Fixup intr_mask operation accordingly. Make sure that TX_EMPTY operations need to be reversed. * request_irq: Set IRQF_DISABLED so that we could load transmit data into Tx FIFO without being distracted by other interrupts. * Remove i2c_dw_xfer_msg() in i2c_dw_xfer(). Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: i2c_dw_read: Remove redundant target address checkerShinya Kuribayashi
I2c_dw_xfer_msg() also has the same target address inconsistency check, and furthermore it checks across all i2c_msg messages, while i2c_dw_read() walks through i2c_msg messages only with_ I2C_M_RD flag. That is, target address check in i2c_dw_read() is redundant and useless. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: i2c_dw_func: Set I2C_FUNC_SMBUS_foo bitsShinya Kuribayashi
Set proper I2C_FUNC_SMBUS_* bits so that the driver could be used with some utilities requiring SMBus functionalities, such as i2c-tools. Note that DW I2C core doesn't support I2C_FUNC_SMBUS_QUICK, as it's not capable of zero-length data transactions. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Initialize byte count variables just prior to being usedShinya Kuribayashi
As the driver and hardware always process the given data in parallel, then it would be better to initialize tx_limit, rx_limit and rx_valid variables just prior to being used. This will help us to send / receive as much data as possible. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: i2c_dw_xfer_msg: Introduce a local "buf" pointerShinya Kuribayashi
While we have a local variable "buf_len" for dev->tx_buf_len, we don't have such local variable for dev->tx_buf pointer. While "buf_len" is restored at first then updated when we start processing a new i2c_msg (determined by STATUS_WRITE_IN_PROGRESS flag), ->tx_buf is different. Such inconsistency makes the code slightly hard to follow. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Divide i2c_dw_xfer_msg into two functionsShinya Kuribayashi
We have some steps at the top of i2c_dw_xfer_msg() to set up a slave address and enable DW I2C core. And it's executed only when we don't have STATUS_WRITE_IN_PROGRESS. But we need to make sure that STATUS_WRITE_IN_PROGRESS only indicates that we have a pending i2c_msg to process. In other words, even if STATUS_WRITE_IN_PROGRESS is not set, that doesn't mean we're at initial state in the I2C transaction. Since i2c_dw_xfer_msg() will be invoked again and again during a transaction, those init steps have a possibility to be re-processed needlessly. For example, this issue easily takes place when processing a combined transaction with a certain condition (the number of tx bytes in the first i2c_msg, equals to the Tx FIFO depth). Consequently we should not use STATUS_WRITE_IN_PROGRESS to determine where we're at in an I2C transaction. It would be better to separate those initialization steps from i2c_dw_xfer_msg(). Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Enable RX_FULL interruptShinya Kuribayashi
Enable RX_FULL interrupt mask by default, and hook it in the interrupt handler. If requested amount of rx data (defined by IC_RX_TL) is not available, we don't have to process i2c_dw_read(). Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Set Tx/Rx FIFO threshold levelsShinya Kuribayashi
As a hardware feature, DW I2C core generates a STOP condition whenever the Tx FIFO becomes empty (strictly speaking, whenever the last byte in the Tx FIFO is sent out), even if we have more bytes to be written. In other words, we must never make "Tx FIFO underrun" happen during a transaction, except for the last byte. For the safety's sake, we'd make TX_EMPTY interrupt get triggered every time one byte is processed. The Rx FIFO threshold needs to be set as well. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Process i2c_msg messages in the interrupt handlerShinya Kuribayashi
Symptom: -------- When we're going to send/receive the longer size of data than the Tx FIFO length, the I2C transaction will be divided into several separated transactions, limited by the Tx FIFO length. Details: -------- As a hardware feature, DW I2C core generates a STOP condition whenever the Tx FIFO becomes empty (strictly speaking, whenever the last byte in the Tx FIFO is sent out), even if we have more bytes to be written. Then, once a new transmit data is written to the Tx FIFO, DW I2C core will initiate a new transaction, which leads to another START condition. This explains how the transaction in question goes, and implies that current tasklet-based dw_i2c_pump_msg() strategy couldn't meet the timing constraint required for avoiding Tx FIFO underrun. To avoid this scenario, we must keep providing new transmit data within a given time period. In case of Fast-mode + 32-byte Tx FIFO, for instance, it takes about 22.5[us] to process single byte, and 720[us] in total. This patch removes the existing tasklet-based "pump" system, and move its jobs into the interrupt handler. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: i2c_dw_xfer_msg: Fix i2c_msg search bugShinya Kuribayashi
In case a work-in-progress i2c_msg has more bytes to be written, we need to set STATUS_WRITE_IN_PROGRESS and exit from the msg_write_idx- searching loop. Otherwise, we will overtake the current msg_write_idx without waiting for its transmission to be processed. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Improved _HCNT/_LCNT calculationShinya Kuribayashi
* Calculate with accurate conditional expressions from DW manuals. * Round ic_clk by adding 0.5 as it's important at high ic_clk rate. * Take into account "tHD;STA" issue for _HCNT calculation. * Take into account "tf" for _LCNT calculation. * Add "cond" and "offset" fot further correction requirements. For _HCNT calculation, there's one issue needs to be carefully considered; DesignWare I2C core doesn't seem to have solid strategy to meet the tHD;STA timing spec. If you configure _HCNT based on the tHIGH timing spec, it easily results in violation of the tHD;STA spec. After many trials, we came to the conclusion that the tHD;STA period is proportional to (_HCNT + 3). For the safety's sake, this should be selected by default. As for _LCNT calculation, DW I2C core has one characteristic behavior; he starts counting the SCL CNTs for the LOW period of the SCL clock (tLOW) as soon as it pulls the SCL line. At that time, he doesn't take into account the fall time of SCL signal (tf), IOW, he starts counting CNTs without confirming the SCL input voltage has dropped to below VIL. This characteristics becomes a problem on some platforms where tf is considerably long, and results in violation of the tLOW timing spec. To make the driver configurable as much as possible for various cases, we'd have separated arguments "tf" and "offset", and for safety default values should be 0.3 us and 0, respectively. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: Remove an useless local variable "num"Shinya Kuribayashi
We couldn't know the original intent for this variable, but at this point it's useless. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2009-12-09i2c-designware: i2c_dw_xfer_msg: Use "struct dw_i2c_dev" pointerShinya Kuribayashi
We don't have to use "struct i2c_adapter" pointer here. Let's use a local "struct dw_i2c_dev" pointer, instead. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Acked-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
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