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* Fix common misspellingsLucas De Marchi2011-03-311-1/+1
| | | | | | Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* bitops: rename for_each_bit() to for_each_set_bit()Akinobu Mita2010-03-061-2/+2
| | | | | | | | | | | | | | | | | | | | Rename for_each_bit to for_each_set_bit in the kernel source tree. To permit for_each_clear_bit(), should that ever be added. The patch includes a macro to map the old for_each_bit() onto the new for_each_set_bit(). This is a (very) temporary thing to ease the migration. [akpm@linux-foundation.org: add temporary for_each_bit()] Suggested-by: Alexey Dobriyan <adobriyan@gmail.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Russell King <rmk@arm.linux.org.uk> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Artem Bityutskiy <dedekind@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* i2c-designware: i2c_dw_handle_tx_abort: Use dev_dbg() for NOACK casesShinya Kuribayashi2009-12-091-2/+7
| | | | | | | | | 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>
* i2c-designware: Cosmetic cleanupsShinya Kuribayashi2009-12-091-13/+14
| | | | | Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-designware: Tx abort cleanupsShinya Kuribayashi2009-12-091-7/+40
| | | | | | | | | | | | * 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>
* i2c-designware: Skip RX_FULL and TX_EMPTY bits on tx abort errorsShinya Kuribayashi2009-12-091-0/+8
| | | | | | | | | | | | | | | 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>
* i2c-designware: i2c_dw_xfer_msg: Fix error handling proceduresShinya Kuribayashi2009-12-091-4/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* i2c-designware: Disable TX_EMPTY when all i2c_msg msgs has been processedShinya Kuribayashi2009-12-091-3/+8
| | | | | | | | | | | | | 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>
* i2c-designware: Process all i2c_msg messages in the interrupt handlerShinya Kuribayashi2009-12-091-9/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* i2c-designware: i2c_dw_read: Remove redundant target address checkerShinya Kuribayashi2009-12-091-5/+0
| | | | | | | | | | 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>
* i2c-designware: i2c_dw_func: Set I2C_FUNC_SMBUS_foo bitsShinya Kuribayashi2009-12-091-1/+6
| | | | | | | | | | | 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>
* i2c-designware: Initialize byte count variables just prior to being usedShinya Kuribayashi2009-12-091-3/+7
| | | | | | | | | | | | 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>
* i2c-designware: i2c_dw_xfer_msg: Introduce a local "buf" pointerShinya Kuribayashi2009-12-091-3/+4
| | | | | | | | | | | | | 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>
* i2c-designware: Divide i2c_dw_xfer_msg into two functionsShinya Kuribayashi2009-12-091-20/+25
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* i2c-designware: Enable RX_FULL interruptShinya Kuribayashi2009-12-091-3/+4
| | | | | | | | | | 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>
* i2c-designware: Set Tx/Rx FIFO threshold levelsShinya Kuribayashi2009-12-091-0/+6
| | | | | | | | | | | | | | | | 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>
* i2c-designware: Process i2c_msg messages in the interrupt handlerShinya Kuribayashi2009-12-091-25/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* i2c-designware: i2c_dw_xfer_msg: Fix i2c_msg search bugShinya Kuribayashi2009-12-091-8/+12
| | | | | | | | | | 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>
* i2c-designware: Improved _HCNT/_LCNT calculationShinya Kuribayashi2009-12-091-9/+84
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 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>
* i2c-designware: Remove an useless local variable "num"Shinya Kuribayashi2009-12-091-4/+2
| | | | | | | | | 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>
* i2c-designware: i2c_dw_xfer_msg: Use "struct dw_i2c_dev" pointerShinya Kuribayashi2009-12-091-4/+3
| | | | | | | | | 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>
* i2c-designware: i2c_dw_read: Use "struct dw_i2c_dev" pointerShinya Kuribayashi2009-12-091-4/+3
| | | | | | | | | 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>
* i2c-designware: Use platform_get_irq helperShinya Kuribayashi2009-12-091-6/+6
| | | | | | 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>
* i2c-designware: Don't use the IC_CLR_INTR register to clear interruptsShinya Kuribayashi2009-12-091-5/+79
| | | | | | | | | | | | | | | | | | | We're strongly discouraged from using the IC_CLR_INTR register because it clears all software-clearable interrupts asserted at the moment. stat = readl(IC_INTR_STAT); : : <=== Interrupts asserted during this period will be lost : readl(IC_CLR_INTR); Instead, use the separately-prepared IC_CLR_* registers. At the same time, this patch adds all remaining interrupt definitions available in the DesignWare I2C hardware. Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
* i2c-designware: Consolidate to use 32-bit word accessesShinya Kuribayashi2009-12-091-38/+38
| | | | | | | | | | | | This driver looks originally meant for armel machines where readw()/ writew() works perfectly fine with this hardware. But that doens't work for big-endian systems. This patch converts all 8/16-bit-aware usages to 32-bit variants. 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>
* i2c: driver for the Synopsys DesignWare I2C controllerBaruch Siach2009-06-241-0/+624
The i2c Linux driver for the DesignWare i2c block of Synopsys, which is meant for AMBA Peripheral Bus. This i2c block is used on SoC chips like the ARM9 based PVG610. Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Ben Dooks <ben-linux@fluff.org>