vdma: xilinx: Use of_dma framework in vdma test client

This patch does following things:
- Uses of_dma framework in vdma test client
- Document the device node for vdma test client
- Add the above node as an example to existing vdma
  device binding documentation

Signed-off-by: Srikanth Thokala <sthokal@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/Documentation/devicetree/bindings/dma/xilinx/axi-vdma.txt b/Documentation/devicetree/bindings/dma/xilinx/axi-vdma.txt
index 1aac22e2655fb16dae8d1998610a33dd6c1836d1..a17092825738c2dcc6813e74b888a996673ed32b 100644 (file)
--- a/Documentation/devicetree/bindings/dma/xilinx/axi-vdma.txt
+++ b/Documentation/devicetree/bindings/dma/xilinx/axi-vdma.txt
@@ -5,6 +5,7 @@ to receive from the video device.
 
 Required properties:
 - compatible: Should be "xlnx,axi-vdma"
+- #dma-cells: Should be <1>, see "dmas" property below
 - reg: Should contain VDMA registers location and length.
 - interrupts: Should contain per channel VDMA interrupts.
 - compatible (child node): It should be either "xlnx,axi-vdma-mm2s-channel" or
@@ -19,6 +20,7 @@ Example:
 
 axi_vdma_0: axivdma@40030000 {
        compatible = "xlnx,axi-vdma";
+       #dma_cells = <1>;
        reg = < 0x40030000 0x10000 >;
        dma-channel@40030000 {
                compatible = "xlnx,axi-vdma-mm2s-channel";
@@ -33,3 +35,22 @@ axi_vdma_0: axivdma@40030000 {
                xlnx,device-id = <0x0>;
        } ;
 } ;
+
+
+* Xilinx Video DMA client
+
+Required properties:
+- dmas: a list of <[Video DMA device phandle] [Channel ID]> pairs,
+       where Channel ID is '0' for write/tx and '1' for read/rx
+       channel.
+- dma-names: a list of DMA channel names, one per "dmas" entry
+
+VDMA Test Client Example:
++++++++++++++++++++++++++
+
+vdmatest_0: vdmatest@0 {
+       compatible ="xlnx,axi-vdma-test";
+       dmas = <&axi_vdma_0 0
+               &axi_vdma_0 1>;
+       dma-names = "vdma0", "vdma1";
+} ;

diff --git a/Documentation/devicetree/bindings/dma/xilinx/vdmatest.txt b/Documentation/devicetree/bindings/dma/xilinx/vdmatest.txt
new file mode 100644 (file)
index 0000000..56acce1
--- /dev/null
+++ b/Documentation/devicetree/bindings/dma/xilinx/vdmatest.txt
@@ -0,0 +1,32 @@
+* Xilinx Video DMA Test client
+
+Required properties:
+- compatible: Should be "xlnx,axi-vdma-test"
+- dmas: a list of <[Video DMA device phandle] [Channel ID]> pairs,
+       where Channel ID is '0' for write/tx and '1' for read/rx
+       channel.
+- dma-names: a list of DMA channel names, one per "dmas" entry
+
+Example:
+++++++++
+
+vdmatest_0: vdmatest@0 {
+       compatible ="xlnx,axi-vdma-test";
+       dmas = <&axi_vdma_0 0
+               &axi_vdma_0 1>;
+       dma-names = "vdma0", "vdma1";
+} ;
+
+
+Xilinx Video DMA Device Node Example
+++++++++++++++++++++++++++++++++++++
+axi_vdma_0: axivdma@44A40000 {
+       compatible = "xlnx,axi-vdma";
+       ...
+       dma-channel@44A40000 {
+               ...
+       } ;
+       dma-channel@44A40030 {
+               ...
+       } ;
+} ;

diff --git a/drivers/dma/xilinx/vdmatest.c b/drivers/dma/xilinx/vdmatest.c
index 9376ab3b65c4c5c564435f87c62244bb6cf52ac1..c504cc30063e914f083c6da054c819f26f7dea4f 100644 (file)
--- a/drivers/dma/xilinx/vdmatest.c
+++ b/drivers/dma/xilinx/vdmatest.c
@@ -10,10 +10,11 @@
  * published by the Free Software Foundation.
  */
 #include <linux/delay.h>
-#include <linux/dmaengine.h>
+#include <linux/of_dma.h>
 #include <linux/init.h>
 #include <linux/kthread.h>
 #include <linux/module.h>
+#include <linux/platform_device.h>
 #include <linux/random.h>
 #include <linux/slab.h>
 #include <linux/wait.h>
@@ -540,67 +541,40 @@ static int vdmatest_add_slave_channels(struct dma_chan *tx_chan,
        return 0;
 }
 
-static bool xdma_filter(struct dma_chan *chan, void *param)
+static int vdmatest_of_probe(struct platform_device *pdev)
 {
-       if (*((int *)chan->private) == *(int *)param)
-               return true;
+       struct dma_chan *chan, *rx_chan;
+       int err;
 
-       return false;
-}
+       chan = dma_request_slave_channel(&pdev->dev, "vdma0");
+       if (IS_ERR(chan)) {
+               pr_err("vdmatest: No Tx channel\n");
+               return PTR_ERR(chan);
+       }
 
-static int __init vdmatest_init(void)
-{
-       dma_cap_mask_t mask;
-       struct dma_chan *chan;
-       int err = 0;
+       rx_chan = dma_request_slave_channel(&pdev->dev, "vdma1");
+       if (IS_ERR(rx_chan)) {
+               err = PTR_ERR(rx_chan);
+               pr_err("vdmatest: No Rx channel\n");
+               goto free_tx;
+       }
 
-       enum dma_data_direction direction;
-       u32 match, device_id = 0;
-       struct dma_chan *rx_chan;
+       err = vdmatest_add_slave_channels(chan, rx_chan);
+       if (err) {
+               pr_err("vdmatest: Unable to add channels\n");
+               goto free_rx;
+       }
+       return 0;
 
-       dma_cap_zero(mask);
-       dma_cap_set(DMA_SLAVE | DMA_PRIVATE, mask);
-
-       for (;;) {
-               direction = DMA_MEM_TO_DEV;
-               match = (direction & 0xFF) | XILINX_DMA_IP_VDMA |
-                               device_id << XILINX_DMA_DEVICE_ID_SHIFT;
-               pr_debug("vdmatest: match is %x\n", match);
-
-               chan = dma_request_channel(mask, xdma_filter, (void *)&match);
-
-               if (chan)
-                       pr_debug("vdmatest: Found tx device\n");
-               else
-                       pr_debug("vdmatest: No more tx channels available\n");
-
-               direction = DMA_DEV_TO_MEM;
-               match = (direction & 0xFF) | XILINX_DMA_IP_VDMA |
-                               device_id << XILINX_DMA_DEVICE_ID_SHIFT;
-               rx_chan = dma_request_channel(mask, xdma_filter, &match);
-
-               if (rx_chan)
-                       pr_debug("vdmatest: Found rx device\n");
-               else
-                       pr_debug("vdmatest: No more rx channels available\n");
-
-               if (chan && rx_chan) {
-                       err = vdmatest_add_slave_channels(chan, rx_chan);
-                       if (err) {
-                               dma_release_channel(chan);
-                               dma_release_channel(rx_chan);
-                       }
-               } else
-                       break;
+free_rx:
+       dma_release_channel(rx_chan);
+free_tx:
+       dma_release_channel(chan);
 
-               device_id++;
-       }
        return err;
 }
-/* when compiled-in wait for drivers to load first */
-late_initcall(vdmatest_init);
 
-static void __exit vdmatest_exit(void)
+static int vdmatest_of_remove(struct platform_device *pdev)
 {
        struct vdmatest_chan *dtc, *_dtc;
        struct dma_chan *chan;
@@ -613,8 +587,25 @@ static void __exit vdmatest_exit(void)
                        dma_chan_name(chan));
                dma_release_channel(chan);
        }
+       return 0;
 }
-module_exit(vdmatest_exit);
+
+static const struct of_device_id vdmatest_of_ids[] = {
+       { .compatible = "xlnx,axi-vdma-test",},
+       {}
+};
+
+static struct platform_driver vdmatest_of_driver = {
+       .driver = {
+               .name = "vdmatest",
+               .owner = THIS_MODULE,
+               .of_match_table = vdmatest_of_ids,
+       },
+       .probe = vdmatest_of_probe,
+       .remove = vdmatest_of_remove,
+};
+
+module_platform_driver(vdmatest_of_driver);
 
 MODULE_AUTHOR("Xilinx, Inc.");
 MODULE_DESCRIPTION("Xilinx AXI VDMA Test Client");

diff --git a/drivers/dma/xilinx/xilinx_axivdma.c b/drivers/dma/xilinx/xilinx_axivdma.c
index 8f30734a0028eef558bf4ffb7b0911210c13c480..435fa4866b1d2f684523fa2bcd8f6aa8f2f47737 100644 (file)
--- a/drivers/dma/xilinx/xilinx_axivdma.c
+++ b/drivers/dma/xilinx/xilinx_axivdma.c
@@ -1272,8 +1272,8 @@ static int xilinx_vdma_chan_probe(struct xilinx_vdma_device *xdev,
        }
 
        /*
-        * Used by dmatest channel matching in slave transfers
-        * Can change it to be a structure to have more matching information
+        * Used by DMA clients who doesnt have a device node and can request
+        * the channel by passing this as a filter to 'dma_request_channel()'.
         */
        chan->private = (chan->direction & 0xff) |
                        XILINX_DMA_IP_VDMA |