* [PATCH RFC v13 3/5] dma: of: add common xlate function for matching by channel id
[not found] ` <1400163335-29853-1-git-send-email-a13xp0p0v88-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
@ 2014-05-15 14:15 ` Alexander Popov
2014-05-15 14:15 ` [PATCH RFC v13 4/5] dma: mpc512x: add device tree binding document Alexander Popov
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Alexander Popov @ 2014-05-15 14:15 UTC (permalink / raw)
To: Gerhard Sittig, Dan Williams, Vinod Koul, Lars-Peter Clausen,
Arnd Bergmann, Anatolij Gustschin, Andy Shevchenko,
Alexander Popov, linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ,
dmaengine-u79uwXL29TY76Z2rM5mHXA
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA
This patch adds a new common OF dma xlate callback function which will match a
channel by it's id. The binding expects one integer argument which it will use to
lookup the channel by the id.
Unlike of_dma_simple_xlate this function is able to handle a system with
multiple DMA controllers. When registering the of dma provider with
of_dma_controller_register a pointer to the dma_device struct which is
associated with the dt node needs to passed as the data parameter.
New function will use this pointer to match only channels which belong to the
specified DMA controller.
Signed-off-by: Alexander Popov <a13xp0p0v88-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
drivers/dma/of-dma.c | 35 +++++++++++++++++++++++++++++++++++
include/linux/of_dma.h | 4 ++++
2 files changed, 39 insertions(+)
diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index e8fe9dc..d5fbeaa 100644
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -218,3 +218,38 @@ struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
&dma_spec->args[0]);
}
EXPORT_SYMBOL_GPL(of_dma_simple_xlate);
+
+/**
+ * of_dma_xlate_by_chan_id - Translate dt property to DMA channel by channel id
+ * @dma_spec: pointer to DMA specifier as found in the device tree
+ * @of_dma: pointer to DMA controller data
+ *
+ * This function can be used as the of xlate callback for DMA driver which wants
+ * to match the channel based on the channel id. When using this xlate function
+ * the #dma-cells propety of the DMA controller dt node needs to be set to 1.
+ * The data parameter of of_dma_controller_register must be a pointer to the
+ * dma_device struct the function should match upon.
+ *
+ * Returns pointer to appropriate dma channel on success or NULL on error.
+ */
+struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma)
+{
+ struct dma_device *dev = ofdma->of_dma_data;
+ struct dma_chan *chan, *candidate = NULL;
+
+ if (!dev || dma_spec->args_count != 1)
+ return NULL;
+
+ list_for_each_entry(chan, &dev->channels, device_node)
+ if (chan->chan_id == dma_spec->args[0]) {
+ candidate = chan;
+ break;
+ }
+
+ if (!candidate)
+ return NULL;
+
+ return dma_get_slave_channel(candidate);
+}
+EXPORT_SYMBOL_GPL(of_dma_xlate_by_chan_id);
diff --git a/include/linux/of_dma.h b/include/linux/of_dma.h
index ae36298..56bc026 100644
--- a/include/linux/of_dma.h
+++ b/include/linux/of_dma.h
@@ -41,6 +41,8 @@ extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
const char *name);
extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
struct of_dma *ofdma);
+extern struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec,
+ struct of_dma *ofdma);
#else
static inline int of_dma_controller_register(struct device_node *np,
struct dma_chan *(*of_dma_xlate)
@@ -66,6 +68,8 @@ static inline struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_s
return NULL;
}
+#define of_dma_xlate_by_chan_id NULL
+
#endif
#endif /* __LINUX_OF_DMA_H */
--
1.8.4.2
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH RFC v13 4/5] dma: mpc512x: add device tree binding document
[not found] ` <1400163335-29853-1-git-send-email-a13xp0p0v88-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2014-05-15 14:15 ` [PATCH RFC v13 3/5] dma: of: add common xlate function for matching by channel id Alexander Popov
@ 2014-05-15 14:15 ` Alexander Popov
2014-05-15 14:15 ` [PATCH RFC v13 5/5] dma: mpc512x: register for device tree channel lookup Alexander Popov
2014-05-22 5:10 ` [PATCH RFC v13 0/5] MPC512x DMA slave s/g support, OF DMA lookup Vinod Koul
3 siblings, 0 replies; 6+ messages in thread
From: Alexander Popov @ 2014-05-15 14:15 UTC (permalink / raw)
To: Gerhard Sittig, Dan Williams, Vinod Koul, Lars-Peter Clausen,
Arnd Bergmann, Anatolij Gustschin, Andy Shevchenko,
Alexander Popov, linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ,
dmaengine-u79uwXL29TY76Z2rM5mHXA
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA
Introduce a device tree binding document for the MPC512x DMA controller
Signed-off-by: Alexander Popov <a13xp0p0v88-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
.../devicetree/bindings/dma/mpc512x-dma.txt | 40 ++++++++++++++++++++++
1 file changed, 40 insertions(+)
create mode 100644 Documentation/devicetree/bindings/dma/mpc512x-dma.txt
diff --git a/Documentation/devicetree/bindings/dma/mpc512x-dma.txt b/Documentation/devicetree/bindings/dma/mpc512x-dma.txt
new file mode 100644
index 0000000..b1cbc3f
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/mpc512x-dma.txt
@@ -0,0 +1,40 @@
+* Freescale MPC512x and MPC8308 DMA Controller
+
+The DMA controller in Freescale MPC512x and MPC8308 SoCs can move
+blocks of memory contents between memory and peripherals or
+from memory to memory.
+
+Refer to "Generic DMA Controller and DMA request bindings" in
+the dma/dma.txt file for a more detailed description of binding.
+
+Required properties:
+- compatible: Should be "fsl,mpc5121-dma" or "fsl,mpc8308-dma"
+- reg: Address and size of the DMA controller's register set
+- Interrupt for the DMA controller. Syntax of interrupt client node
+ is described in interrupt-controller/interrupts.txt
+
+Optional properties:
+- #dma-cells: The length of the DMA specifier, must be <1>.
+ Each channel of this DMA controller has a peripheral request line,
+ this assignment is fixed in hardware. The cell in dmas property
+ of a client device represents the channel number
+
+Example:
+
+ dma0: dma@14000 {
+ compatible = "fsl,mpc5121-dma";
+ reg = <0x14000 0x1800>;
+ interrupts = <65 0x8>;
+ #dma-cells = <1>;
+ };
+
+DMA clients must use the format described in dma/dma.txt
+
+Example:
+
+ sdhc@1500 {
+ compatible = "fsl,mpc5121-sdhc";
+ /* ... */
+ dmas = <&dma0 30>;
+ dma-names = "rx-tx";
+ };
--
1.8.4.2
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH RFC v13 5/5] dma: mpc512x: register for device tree channel lookup
[not found] ` <1400163335-29853-1-git-send-email-a13xp0p0v88-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2014-05-15 14:15 ` [PATCH RFC v13 3/5] dma: of: add common xlate function for matching by channel id Alexander Popov
2014-05-15 14:15 ` [PATCH RFC v13 4/5] dma: mpc512x: add device tree binding document Alexander Popov
@ 2014-05-15 14:15 ` Alexander Popov
2014-05-22 5:10 ` [PATCH RFC v13 0/5] MPC512x DMA slave s/g support, OF DMA lookup Vinod Koul
3 siblings, 0 replies; 6+ messages in thread
From: Alexander Popov @ 2014-05-15 14:15 UTC (permalink / raw)
To: Gerhard Sittig, Dan Williams, Vinod Koul, Lars-Peter Clausen,
Arnd Bergmann, Anatolij Gustschin, Andy Shevchenko,
Alexander Popov, linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ,
dmaengine-u79uwXL29TY76Z2rM5mHXA
Cc: devicetree-u79uwXL29TY76Z2rM5mHXA
Register the controller for device tree based lookup of DMA channels
(non-fatal for backwards compatibility with older device trees) and
provide the '#dma-cells' property in the shared mpc5121.dtsi file
Signed-off-by: Alexander Popov <a13xp0p0v88-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
arch/powerpc/boot/dts/mpc5121.dtsi | 1 +
drivers/dma/mpc512x_dma.c | 13 ++++++++++++-
2 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/boot/dts/mpc5121.dtsi b/arch/powerpc/boot/dts/mpc5121.dtsi
index 2c0e155..7f9d14f 100644
--- a/arch/powerpc/boot/dts/mpc5121.dtsi
+++ b/arch/powerpc/boot/dts/mpc5121.dtsi
@@ -498,6 +498,7 @@
compatible = "fsl,mpc5121-dma";
reg = <0x14000 0x1800>;
interrupts = <65 0x8>;
+ #dma-cells = <1>;
};
};
diff --git a/drivers/dma/mpc512x_dma.c b/drivers/dma/mpc512x_dma.c
index 2ad4373..881db2b 100644
--- a/drivers/dma/mpc512x_dma.c
+++ b/drivers/dma/mpc512x_dma.c
@@ -53,6 +53,7 @@
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
+#include <linux/of_dma.h>
#include <linux/of_platform.h>
#include <linux/random.h>
@@ -1036,7 +1037,15 @@ static int mpc_dma_probe(struct platform_device *op)
if (retval)
goto err_free2;
- return retval;
+ /* Register with OF helpers for DMA lookups (nonfatal) */
+ if (dev->of_node) {
+ retval = of_dma_controller_register(dev->of_node,
+ of_dma_xlate_by_chan_id, mdma);
+ if (retval)
+ dev_warn(dev, "Could not register for OF lookup\n");
+ }
+
+ return 0;
err_free2:
if (mdma->is_mpc8308)
@@ -1057,6 +1066,8 @@ static int mpc_dma_remove(struct platform_device *op)
struct device *dev = &op->dev;
struct mpc_dma *mdma = dev_get_drvdata(dev);
+ if (dev->of_node)
+ of_dma_controller_free(dev->of_node);
dma_async_device_unregister(&mdma->dma);
if (mdma->is_mpc8308) {
free_irq(mdma->irq2, mdma);
--
1.8.4.2
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH RFC v13 0/5] MPC512x DMA slave s/g support, OF DMA lookup
[not found] ` <1400163335-29853-1-git-send-email-a13xp0p0v88-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
` (2 preceding siblings ...)
2014-05-15 14:15 ` [PATCH RFC v13 5/5] dma: mpc512x: register for device tree channel lookup Alexander Popov
@ 2014-05-22 5:10 ` Vinod Koul
[not found] ` <20140522051023.GV21128-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
3 siblings, 1 reply; 6+ messages in thread
From: Vinod Koul @ 2014-05-22 5:10 UTC (permalink / raw)
To: Alexander Popov
Cc: Gerhard Sittig, Dan Williams, Lars-Peter Clausen, Arnd Bergmann,
Anatolij Gustschin, Andy Shevchenko,
linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ,
dmaengine-u79uwXL29TY76Z2rM5mHXA,
devicetree-u79uwXL29TY76Z2rM5mHXA
On Thu, May 15, 2014 at 06:15:30PM +0400, Alexander Popov wrote:
> 2013/7/14 Gerhard Sittig <gsi-ynQEQJNshbs@public.gmane.org>:
> > this series
> > - introduces slave s/g support (that's support for DMA transfers which
> > involve peripherals in contrast to mem-to-mem transfers)
> > - adds device tree based lookup support for DMA channels
> > - combines floating patches and related feedback which already covered
> > several aspects of what the suggested LPB driver needs, to demonstrate
> > how integration might be done
>
> ...
>
> Changes in v12:
> A new patch (part 2/7) is added to this series.
> Part 6/7:
> - change the description of 'compatible' property according part 2/7;
> - improve the document according Gerhard's feedback;
>
> Parts 1/7, 2/7 and 4/7 have been applied by Vinod Koul and
> are excluded from v13.
>
> Changes in v13:
> A new patch (part 1/5) is added to this series.
> Part 2/5:
> - fix style issue;
> - improve comments;
You need to cc DT- list for 3 to 5 patches. Need ack before we can apply.
I suspect 4/5 should come first out of these 3.
Also in future pls use right subsystem name "dmaengine". Also why are these
tagged as RFC still?
--
~Vinod
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
^ permalink raw reply [flat|nested] 6+ messages in thread