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path: root/drivers/spi/spi-pl022.c
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2012-03-07spi: create a message queueing infrastructureLinus Walleij
This rips the message queue in the PL022 driver out and pushes it into (optional) common infrastructure. Drivers that want to use the message pumping thread will need to define the new per-messags transfer methods and leave the deprecated transfer() method as NULL. Most of the design is described in the documentation changes that are included in this patch. Since there is a queue that need to be stopped when the system is suspending/resuming, two new calls are implemented for the device drivers to call in their suspend()/resume() functions: spi_master_suspend() and spi_master_resume(). ChangeLog v1->v2: - Remove Kconfig entry and do not make the queue support optional at all, instead be more agressive and have it as part of the compulsory infrastructure. - If the .transfer() method is implemented, delete print a small deprecation notice and do not start the transfer pump. - Fix a bitrotted comment. ChangeLog v2->v3: - Fix up a problematic sequence courtesy of Chris Blair. - Stop rather than destroy the queue on suspend() courtesy of Chris Blair. Signed-off-by: Chris Blair <chris.blair@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Tested-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-02-22dmaengine: Pass dma_slave_config .device_fc = NULL for all existing usersViresh Kumar
.device_fc is added in struct dma_slave_config recently. All user drivers, which want DMA to be the flow controller must pass this field as false. As earlier driver don't look to use this feature, mark it false for now. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-02-13Fix section mismatch in spi-pl022.cRussell King
WARNING: drivers/spi/built-in.o(.devinit.text+0xdb8): Section mismatch in reference from the function pl022_probe() to the function .init.text:pl022_dma_probe() The function __devinit pl022_probe() references a function __init pl022_dma_probe(). If pl022_dma_probe is only used by pl022_probe then annotate pl022_dma_probe with a matching annotation. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-02-02spi/pl022: Add high priority message pump supportChris Blair
This switches the PL022 worker to a kthread in order to get hold of a mechanism to control the message pump priority. On low-latency systems elevating the message kthread to realtime priority give a real sleek response curve. This has been confirmed by measurements. Realtime priority elevation for a certain PL022 port can be requested from platform data. Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Chris Blair <chris.blair@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-01-17Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dmaLinus Torvalds
* 'next' of git://git.infradead.org/users/vkoul/slave-dma: (53 commits) ARM: mach-shmobile: specify CHCLR registers on SH7372 dma: shdma: fix runtime PM: clear channel buffers on reset dma/imx-sdma: save irq flags when use spin_lock in sdma_tx_submit dmaengine/ste_dma40: clear LNK on channel startup dmaengine: intel_mid_dma: remove legacy pm interface ASoC: mxs: correct 'direction' of device_prep_dma_cyclic dmaengine: intel_mid_dma: error path fix dmaengine: intel_mid_dma: locking and freeing fixes mtd: gpmi-nand: move to dma_transfer_direction mtd: fix compile error for gpmi-nand mmc: mxs-mmc: fix the dma_transfer_direction migration dmaengine: add DMA_TRANS_NONE to dma_transfer_direction dma: mxs-dma: Don't use CLKGATE bits in CTRL0 to disable DMA channels dma: mxs-dma: make mxs_dma_prep_slave_sg() multi user safe dma: mxs-dma: Always leave mxs_dma_init() with the clock disabled. dma: mxs-dma: fix a typo in comment DMA: PL330: Remove pm_runtime_xxx calls from pl330 probe/remove video i.MX IPU: Fix display connections i.MX IPU DMA: Fix wrong burstsize settings dmaengine/ste_dma40: allow fixed physical channel ... Fix up conflicts in drivers/dma/{Kconfig,mxs-dma.c,pl330.c} The conflicts looked pretty trivial, but I'll ask people to verify them.
2012-01-07Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6Linus Torvalds
Changes queued in gpio/next for the start of the 3.3 merge window * tag 'gpio-for-linus-20120104' of git://git.secretlab.ca/git/linux-2.6: gpio: Add decode of WM8994 GPIO configuration gpio: Convert GPIO drivers to module_platform_driver gpio: Fix typo in comment in Samsung driver gpio: Explicitly index samsung_gpio_cfgs gpio: Add Linus Walleij as gpio co-maintainer of: Add device tree selftests of: create of_phandle_args to simplify return of phandle parsing data gpio/powerpc: Eliminate duplication of of_get_named_gpio_flags() gpio/microblaze: Eliminate duplication of of_get_named_gpio_flags() gpiolib: output basic details and consolidate gpio device drivers pch_gpio: Change company name OKI SEMICONDUCTOR to LAPIS Semiconductor pch_gpio: Support new device LAPIS Semiconductor ML7831 IOH spi/pl022: make the chip deselect handling thread safe spi/pl022: add support for pm_runtime autosuspend spi/pl022: disable the PL022 block when unused spi/pl022: move device disable to workqueue thread spi/pl022: skip default configuration before suspending spi/pl022: fix build warnings spi/pl022: only enable RX interrupts when TX is complete
2012-01-06Merge branch 'amba-modalias' of ↵Linus Torvalds
git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm * 'amba-modalias' of git://ftp.arm.linux.org.uk/pub/linux/arm/kernel/git-cur/linux-2.6-arm: sound: aaci: Enable module alias autogeneration for AMBA drivers watchdog: sp805: Enable module alias autogeneration for AMBA drivers fbdev: amba: Enable module alias autogeneration for AMBA drivers serial: pl011: Enable module alias autogeneration for AMBA drivers serial: pl010: Enable module alias autogeneration for AMBA drivers spi: pl022: Enable module alias autogeneration for AMBA drivers rtc: pl031: Enable module alias autogeneration for AMBA drivers rtc: pl030: Enable module alias autogeneration for AMBA drivers mmc: mmci: Enable module alias autogeneration for AMBA drivers input: ambakmi: Enable module alias autogeneration for AMBA drivers gpio: pl061: Enable module alias autogeneration for AMBA drivers dmaengine: pl330: Enable module alias autogeneration for AMBA drivers dmaengine: pl08x: Enable module alias autogeneration for AMBA drivers hwrng: nomadik: Enable module alias autogeneration for AMBA drivers ARM: amba: Auto-generate AMBA driver module aliases during modpost ARM: amba: Move definition of struct amba_id to mod_devicetable.h
2011-12-01spi/pl022: make the chip deselect handling thread safeVirupax Sadashivpetimath
There is a possibility that the pump_message and giveback run in parallel on a SMP system. Both the pump_message and giveback threads work on the same SPI message queue. Results will be in correct if the pump_message gets to work on the queue first. when the pump_message works with the queue, it reads the head of the queue and removes it from the queue. pump_message activates the chip select depending on this message read. This leads to giveback working on the modified queue or a emptied queue. If the queue is empty or if the next message on the queue (which is not the actual next message, as the pump message has removed the next message from the queue) is not for the same SPI device as that Of the previous one, giveback will de-activate the chip select activated by pump_message(), which is wrong. To solve this problem pump_message is made not to run and access the queue until the giveback is done handling the queue. I.e. by making the cur_msg NULL after the giveback has read the queue. Also a state variable has been introduced to keep track of when the CS for next message is already activated and avoid to double-activate it. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-12-01spi/pl022: add support for pm_runtime autosuspendChris Blair
Adds support for configuring the spi bus to use autosuspend for runtime power management. This can reduce the latency in starting an spi transfer by not suspending the device immediately following completion of a transfer. If another transfer then takes place before the autosuspend timeout, the call to resume the device can return immediately rather than needing to risk sleeping in order to resume the device. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Chris Blair <chris.blair@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-12-01spi/pl022: disable the PL022 block when unusedVirupax Sadashivpetimath
Make sure we clear the enable bit when the block is not used. This will save some energy in certain hardware versions. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-12-01spi/pl022: move device disable to workqueue threadChris Blair
Moves the disabling of the device and clocks to the same thread in which the device and clocks are enabled. This avoids SMP issues where the device can be enabled for a transfer by one thread and then disabled by the completion of the previous transfer in another thread. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Chris Blair <chris.blair@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-12-01spi/pl022: skip default configuration before suspendingVirupax Sadashivpetimath
The loading of the default configuration before suspending has been in the driver since its inception, but it is not really needed. Especially so since we take to all the trouble of enabling and disabling power and clock just to do this. Let's scrap this now. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-12-01spi/pl022: fix build warningsJonas Aaberg
The driver build complains with newer compilers unless you initialize this struct properly. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-12-01spi/pl022: only enable RX interrupts when TX is completeChris Blair
For interrupt mode transfers, start with only TX interrupts enabled to reduce the overall number of interrupts received. Once TX is complete, enable RX interrupts to complete the transfer. Reviewed-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Chris Blair <chris.blair@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2011-11-22spi: pl022: Enable module alias autogeneration for AMBA driversDave Martin
Signed-off-by: Dave Martin <dave.martin@linaro.org> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Linus Walleij <linus.walleij@linaro.org>
2011-11-17Merge branch 'dma_slave_direction' into next_test_dirnVinod Koul
resolved conflicts: drivers/media/video/mx3_camera.c
2011-11-08ARM: 7149/1: spi/pl022: Enable clock in probeUlf Hansson
Make sure we enable the clock before leaving probe. Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com> Acked-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-10-31spi, serial: move to dma_transfer_directionVinod Koul
fixup usage of dma direction by introducing dma_transfer_direction, this patch moves spi, serial drivers to use new enum Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Alan Cox <alan@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@iki.fi>
2011-10-29Merge branch 'spi/next' of git://git.secretlab.ca/git/linux-2.6Linus Torvalds
* 'spi/next' of git://git.secretlab.ca/git/linux-2.6: drivercore: Add helper macro for platform_driver boilerplate spi: irq: Remove IRQF_DISABLED OMAP: SPI: Fix the trying to free nonexistent resource error spi/spi-ep93xx: add module.h include spi/tegra: fix compilation error in spi-tegra.c spi: spi-dw: fix all sparse warnings spi/spi-pl022: Call pl022_dma_remove(pl022) only if enable_dma is true spi/spi-pl022: calculate_effective_freq() must set rate <= requested rate spi/spi-pl022: Don't allocate more sg than required. spi/spi-pl022: Use GFP_ATOMIC for allocation from tasklet spi/spi-pl022: Resolve formatting issues
2011-09-27clk: spi-pl022: convert to clk_prepare()/clk_unprepare()Russell King
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-22ARM: 7079/1: spi: Fix builderror in spi-pl022.cPeter Hüwe
This patch fixes a build error, introduced by commit (67fc8b9f, "PM: add runtime PM support to core Primecell driver") which unfortunately was a little bit incomplete and did contain a typo (11 instead of 22). I'm not sure how this patch could have been tested back then, if it doesn't even compile ;) The build failure was: drivers/spi/spi-pl022.c:2292: error: 'adev' undeclared (first use in this function) drivers/spi/spi-pl022.c:2344: error: 'pl022_suspend' undeclared here (not in a function) The build failure appears e.g. for the u8500 and realview defconfig. Signed-off-by: Peter Huewe <peterhuewe@gmx.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-22PM: add runtime PM support to core Primecell driverRussell King
Add runtime PM support to the core Primecell driver, following the PCI model of how this is done. Rather than having every driver fiddle about with enabling runtime PM, that's dealt with in the core and instead, drivers just do a put() in their probe and a balancing get() in their remove function to activate runtime PM for the device. As we're dealing with enabling runtime PM in the core, fix up spi-pl022 as it must not enable and disable runtime PM itself anymore. Tested-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2011-09-21spi/spi-pl022: Call pl022_dma_remove(pl022) only if enable_dma is trueViresh Kumar
pl022_dma_remove() should be called only if enable_dma is true. There is no point calling it when pl022_dma_probe() is not called, which again depends on enable_dma. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Tested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-09-21spi/spi-pl022: calculate_effective_freq() must set rate <= requested rateViresh Kumar
There were few issues with calculate_effective_freq() routine: - It was returning first rate found >= requested rate. Now, if system have spi's rate as 83 MHz, with possible prescaled rates as 83, 41.5, 20.75, 13.83 (as we can prescale with multiples of 2). If user has given rate to be programmed as 22 MHz, then driver programmes it to 41.5 MHz. This looks to be incorrect, as user might have given the upper limit of the device, and we are programming it above it. - Driver finds the first satisfying rate and programmes it, but with other values of scr & cpsdvsr, it is possible to get more closer rate. This patch fixes these two issues, with some reformatting inside the code. This also creates a inline routine to calculate prescaled rate based on spi's rate, cpsdvsr and scr. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Tested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-09-21spi/spi-pl022: Don't allocate more sg than required.Viresh Kumar
In routine configure_dma(), if transfer->len = PAGE_SIZE, then pages is one more than required. While leads to one more sg getting allocated. This is wrong. Correct this to allocate correct number of sg. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Tested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-09-21spi/spi-pl022: Use GFP_ATOMIC for allocation from taskletViresh Kumar
tasklets don't allow invocation to sleeping routines. In configure_dma() routine, sg_alloc_table() was called with GFP_KERNEL flag and so this causes crash when called from tasklet. Replace GFP_KERNEL with GFP_ATOMIC to get this fixed. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Tested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-09-20spi/spi-pl022: Resolve formatting issuesViresh Kumar
There were few formatting related issues in code. This patch fixes them. Fixes include: - Remove extra blank lines - align code to 80 cols - combine several lines to one line - Replace multiple spaces with tabs - Remove spaces before labels Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Tested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-08-02spi/pl022: remove function cannot exitLinus Walleij
The remove function in the PL022 driver cannot abort the remove function any way, so restructure the code so as not to make that assumption. Remove will now proceed no matter whether it can stop the transfer queue or not. Reported-by: Russell King <linux@arm.linux.org.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-06-17Merge branch 'spi/merge' into spi/nextGrant Likely
2011-06-16spi/pl022: strengthen FIFO watermark level checksLinus Walleij
The platform configuration can select custom FIFO watermarks, but these may conflict the actual FIFO size of the PL022 variant if set too high. So strengthen the sanity checks to deny any conflicting settings. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-06-16spi/pl022: support runtime PMRabin Vincent
Insert notifiers for the runtime PM API. With this the runtime PM layer kicks in to action where used. Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com> Reviewed-by: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com> Reviewed-by: Jonas Aberg <jonas.aberg@stericsson.com> Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com> [Rebased to Linux 3.0-rc3, edit description] Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-06-16spi/pl022: initialize burstsize from FIFO trigger levelLinus Walleij
Configure the DMA burstsize from the FIFO trigger level supplied with the controller configuration data. This is based on a patch from Virupax, but I rewrote it differently. Reported-by: Virupax Sadashivpetimath <virupax.sadashivpetimath@stericsson.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-06-06spi: reorganize driversGrant Likely
Sort the SPI makefile and enforce the naming convention spi_*.c for spi drivers. This change also rolls the contents of atmel_spi.h into the .c file since there is only one user of that particular include file. v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be be the predominant pattern for subsystem prefixes. - Clean up filenames in Kconfig and header comment blocks Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org>