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2013-02-28dmaengine: dw_dmac: move to generic DMA bindingArnd Bergmann
The original device tree binding for this driver, from Viresh Kumar unfortunately conflicted with the generic DMA binding, and did not allow to completely seperate slave device configuration from the controller. This is an attempt to replace it with an implementation of the generic binding, but it is currently completely untested, because I do not have any hardware with this particular controller. The patch applies on top of the slave-dma tree, which contains both the base support for the generic DMA binding, as well as the earlier attempt from Viresh. Both of these are currently not merged upstream however. This version incorporates feedback from Viresh Kumar, Andy Shevchenko and Russell King. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Vinod Koul <vinod.koul@linux.intel.com> Cc: devicetree-discuss@lists.ozlabs.org Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-02-14ARM: dts: pl330: Add #dma-cells for generic dma binding supportPadmavathi Venna
This patch adds #dma-cells property to PL330 DMA controller nodes for supporting generic dma dt bindings on samsung exynos5250 platform. Signed-off-by: Padmavathi Venna <padma.v@samsung.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-01-07dmaengine: dw_dmac: Enhance device tree supportViresh Kumar
dw_dmac driver already supports device tree but it used to have its platform data passed the non-DT way. This patch does following changes: - pass platform data via DT, non-DT way still takes precedence if both are used. - create generic filter routine - Earlier slave information was made available by slave specific filter routines in chan->private field. Now, this information would be passed from within dmac DT node. Slave drivers would now be required to pass bus_id (a string) as parameter to this generic filter(), which would be compared against the slave data passed from DT, by the generic filter routine. - Update binding document Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [Fixed __devinit usage] Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2013-01-06of: dma: fix typos in generic dma binding definitionMatt Porter
Some semicolons were left out in the examples. The #dma-channels and #dma-requests properties have a prefix that is, by convention, reserved for cell size properties. Rename those properties to dma-channels and dma-requests. Signed-off-by: Matt Porter <mporter@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Jon Hunter <jon-hunter@ti.com> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2013-01-06of: Add generic device tree DMA helpersJon Hunter
This is based upon the work by Benoit Cousson [1] and Nicolas Ferre [2] to add some basic helpers to retrieve a DMA controller device_node and the DMA request/channel information. Aim of DMA helpers - The purpose of device-tree is to describe the capabilites of the hardware. Thinking about DMA controllers purely from the context of the hardware to begin with, we can describe a device in terms of a DMA controller as follows ... 1. Number of DMA controllers 2. Number of channels (maybe physical or logical) 3. Mapping of DMA requests signals to DMA controller 4. Number of DMA interrupts 5. Mapping of DMA interrupts to channels - With the above in mind the aim of the DT DMA helper functions is to extract the above information from the DT and provide to the appropriate driver. However, due to the vast number of DMA controllers and not all are using a common driver (such as DMA Engine) it has been seen that this is not a trivial task. In previous discussions on this topic the following concerns have been raised ... 1. How does the binding support devices with multiple DMA controllers? 2. How to support both legacy DMA controllers not using DMA Engine as well as those that support DMA Engine. 3. When using with DMA Engine how do we support the various implementations where the opaque filter function parameter differs between implementations? 4. How do we handle DMA channels that are identified with a string versus a integer? - Hence the design of the DMA helpers has to accomodate the above or align on an agreement what can be or should be supported. Design of DMA helpers 1. Registering DMA controllers In the case of DMA controllers that are using DMA Engine, requesting a channel is performed by calling the following function. struct dma_chan *dma_request_channel(dma_cap_mask_t mask, dma_filter_fn filter_fn, void *filter_param); The mask variable is used to match a type of the device controller in a list of controllers. The filter_fn and filter_param are used to identify the required dma channel and return a handle to the dma channel of type dma_chan. From the examples I have seen, the mask and filter_fn are constant for a given DMA controller and therefore, we can specify these as controller specific data when registering the DMA controller with the device-tree DMA helpers. The filter_param variable is of an unknown type and is typically specific to the DMA engine implementation for a given DMA controller. To allow some flexibility in the type and formating of this filter_param we employ an xlate to translate the device-tree binding information into the appropriate format. The xlate function used for a DMA controller can also be specified when registering the DMA controller with the device-tree DMA helpers. Based upon the above, a function for registering the DMA controller with the DMA helpers now looks like the below. The data variable is used to pass a pointer to DMA controller specific data used by the xlate function. int of_dma_controller_register(struct device_node *np, struct dma_chan *(*of_dma_xlate) (struct of_phandle_args *, struct of_dma *), void *data) For example, in the case where DMA engine is used, we define the following structure (that stores the DMA engine capability mask and filter function) and pass this to the data variable in the above function. struct of_dma_filter_info { dma_cap_mask_t dma_cap; dma_filter_fn filter_fn; }; 2. Representing and requesting channel information Please see the dma binding documentation included in this patch for a description of how DMA controllers and client information should be represented with device-tree. For more information on how this binding came about please see [3]. In addition to this, feedback received from the Linux kernel summit showed a consensus (among those who attended) to use a name to identify DMA client information [4]. A DMA channel can be requested by calling the following function, where name is a required parameter used for identifying a DMA channel. This function has been designed to return a structure of type dma_chan to work with the DMA engine driver. Note that if DMA engine is used then drivers should be using the DMA engine API dma_request_slave_channel() (implemented in part 2 of this series, "dmaengine: add helper function to request a slave DMA channel") which will in turn call the below function if device-tree is present. The aim being to have a common DMA engine interface regardless of whether device tree is being used. struct dma_chan *of_dma_request_slave_channel(struct device_node *np, char *name) 3. Supporting legacy devices not using DMA Engine These devices present a problem, as there may not be a uniform way to easily support them with regard to device tree. Ideally, these should be migrated to DMA engine. However, if this is not possible, then they should still be able to use this binding, the only constaint imposed by this implementation is that when requesting a DMA channel via of_dma_request_slave_channel(), it will return a type of dma_chan. This implementation has been tested on OMAP4430 using the kernel v3.6-rc5. I have validated that MMC is working on the PANDA board with this implementation. My development branch for testing on OMAP can be found here [5]. v6: - minor corrections in DMA binding documentation v5: - minor update to binding documentation - added loop to exhaustively search for a slave channel in the case where there could be alternative channels available v4: - revert the removal of xlate function from v3 - update the proposed binding format and APIs based upon discussions [3] v3: - avoid passing an xlate function and instead pass DMA engine parameters - define number of dma channels and requests in dma-controller node v2: - remove of_dma_to_resource API - make property #dma-cells required (no fallback anymore) - another check in of_dma_xlate_onenumbercell() function [1] http://article.gmane.org/gmane.linux.drivers.devicetree/12022 [2] http://article.gmane.org/gmane.linux.ports.arm.omap/73622 [3] http://marc.info/?l=linux-omap&m=133582085008539&w=2 [4] http://pad.linaro.org/arm-mini-summit-2012 [5] https://github.com/jonhunter/linux/tree/dev-dt-dma Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Benoit Cousson <b-cousson@ti.com> Cc: Stephen Warren <swarren@nvidia.com> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Russell King <linux@arm.linux.org.uk> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Dan Williams <djbw@fb.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Jon Hunter <jon-hunter@ti.com> Reviewed-by: Stephen Warren <swarren@wwwdotorg.org> Acked-by: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-11-20dma: mv_xor: add Device Tree bindingThomas Petazzoni
This patch finally adds a Device Tree binding to the mv_xor driver. Thanks to the previous cleanup patches, the Device Tree binding is relatively simply: one DT node per XOR engine, with sub-nodes for each XOR channel of the XOR engine. The binding obviously comes with the necessary documentation. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Cc: devicetree-discuss@lists.ozlabs.org
2012-10-02Merge branch 'for-v3.7' of ↵Linus Torvalds
git://git.linaro.org/people/mszyprowski/linux-dma-mapping Pull CMA and DMA-mapping updates from Marek Szyprowski: "This time the pull request is rather small, because the further redesign patches were not ready on time. This pull request consists of the patches which extend ARM DMA-mapping subsystem with support for CPU coherent (ACP) DMA busses. The first client of the new version is HighBank SATA driver. The second part of the pull request includes various cleanup for both CMA common code and ARM DMA-mapping subsystem." Fix up trivial add-add conflict due to the "dma-coherent" DT property being added next to the "calxeda,port-phys" property for the Calxeda AHCI controller. * 'for-v3.7' of git://git.linaro.org/people/mszyprowski/linux-dma-mapping: ARM: dma-mapping: Remove unsed var at arm_coherent_iommu_unmap_page ARM: highbank: add coherent DMA setup ARM: kill off arch_is_coherent ARM: add coherent iommu dma ops ARM: add coherent dma ops ARM: dma-mapping: Refrain noisy console message ARM: dma-mapping: Small logical clean up drivers: dma-contiguous: refactor dma_alloc_from_contiguous()
2012-10-02ARM: highbank: add coherent DMA setupRob Herring
Some highbank DMA masters can support coherent (ACP) or non-coherent DMA. This sets up dma_map_ops for masters which are configured for coherent DMA. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
2012-09-21ARM: dt: mmp-dma: add binding fileZhangfei Gao
Signed-off-by: Zhangfei Gao <zhangfei.gao@marvell.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
2012-05-26Merge tag 'dt2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-socLinus Torvalds
Pull arm-soc device tree conversions (part 2) from Olof Johansson: "These continue the device tree work from part 1, this set is for the tegra, mxs and imx platforms, all of which have dependencies on clock or pinctrl changes submitted earlier." Fix up trivial conflicts due to nearby changes in drivers/{gpio/gpio,i2c/busses/i2c}-mxs.c * tag 'dt2' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (73 commits) ARM: dt: tegra: invert status=disable vs status=okay ARM: dt: tegra: consistent basic property ordering ARM: dt: tegra: sort nodes based on bus order ARM: dt: tegra: remove duplicate device_type property ARM: dt: tegra: consistenly use lower-case for hex constants ARM: dt: tegra: format regs properties consistently ARM: dt: tegra: gpio comment cleanup ARM: dt: tegra: remove unnecessary unit addresses ARM: dt: tegra: whitespace cleanup ARM: dt: tegra cardhu: fix typo in SDHCI node name ARM: dt: tegra: cardhu: register core regulator tps62361 ARM: dt: tegra30.dtsi: Add SMMU node ARM: dt: tegra20.dtsi: Add GART node ARM: dt: tegra30.dtsi: Add Memory Controller(MC) nodes ARM: dt: tegra20.dtsi: Add Memory Controller(MC) nodes ARM: dt: tegra: Add device tree support for AHB ARM: dts: enable audio support for imx28-evk ARM: dts: enable i2c device for imx28-evk i2c: mxs: add device tree probe support ARM: dts: enable mmc for imx28-evk ...
2012-05-12dma: mxs-dma: add device tree probe supportDong Aisheng
Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Rob Herring <rob.herring@calxeda.com> Cc: Rob Landley <rob@landley.net> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Huang Shijie <b32955@freescale.com> Signed-off-by: Dong Aisheng <dong.aisheng@linaro.org> Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Marek Vasut <marex@denx.de> Acked-by: Vinod Koul <vinod.koul@intel.com>
2012-05-11dmaengine: dw_dma: add Device Tree probing capabilityViresh Kumar
SPEAr platforms now support DT and so must convert all drivers to support DT. This patch adds DT probing support for Synopsys DMA controller and updates its documentation too. Signed-off-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2012-02-06ARM: dt: tegra: Add Tegra APB DMA device tree bindingStephen Warren
Document binding, and add the node to tegra*.dtsi. The driver isn't actually instantiated from this node yet, but the I2S binding will rely on being able to refer to the APB DMA node using a phandle. Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Olof Johansson <olof@lixom.net>
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.
2011-12-23DMA: PL330: Add device tree supportThomas Abraham
For PL330 dma controllers instantiated from device tree, the channel lookup is based on phandle of the dma controller and dma request id specified by the client node. During probe, the private data of each channel of the controller is set to point to the device node of the dma controller. The 'chan_id' of the each channel is used as the dma request id. Client driver requesting dma channels specify the phandle of the dma controller and the request id. The pl330 filter function converts the phandle to the device node pointer and matches that with channel's private data. If a match is found, the request id from the client node and the 'chan_id' of the channel is matched. A channel is found if both the values match. Acked-by: Jassi Brar <jassisinghbrar@gmail.com> Acked-by: Boojin Kim <boojin.kim@samsung.com> Signed-off-by: Thomas Abraham <thomas.abraham@linaro.org> Reviewed-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2011-11-10dmaengine: at_hdmac: add device tree supportNicolas Ferre
Add device tree probe support for atmel at_hdmac DMA driver. Bindings are added to specify DMA controller configuration. Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-07-27dmaengine: imx-sdma: add device tree probe supportShawn Guo
It adds device tree probe support for imx-sdma driver. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Cc: Grant Likely <grant.likely@secretlab.ca> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Acked-by: Vinod Koul <vinod.koul@intel.com>