[PATCH v5 0/3] dmaengine: Initial debugfs support

[PATCH v5 0/3] dmaengine: Initial debugfs support

[Peter Ujfalusi]

Hi,

Changes sicne v4:
- Move the dmaengine_debugfs_init() from late_initcall to be called from
  dma_bus_init to avoid races due to probe orders of drivers.
- Separate patch to create DMA driver directories for debugfs

Changes since v3:
- Create a directory for dmaengine and name the initial file as summary
- Function to get the debugfs root for DMA drivers if they want to place files
- Custom dbg_summary_show implementation for k3-udma

Changes since v2:
- Use dma_chan_name() for printing the channel's name

Changes since v1:
- Use much more simplified fops for the debugfs file (via DEFINE_SHOW_ATTRIBUTE)
- do not allow modification to dma_device_list while the debugfs file is read
- rename the slave_name to dbg_client_name (it is only for debugging)
- print information about dma_router if it is used by the channel
- Formating of the output slightly changed

The basic debugfs file (/sys/kernel/debug/dmaengine/summary) can be used to
query basic information about the DMAengine usage (am654-evm):

# cat /sys/kernel/debug/dmaengine/summary
dma0 (285c0000.dma-controller): number of channels: 96

dma1 (31150000.dma-controller): number of channels: 267
 dma1chan0    | 2b00000.mcasp:tx
 dma1chan1    | 2b00000.mcasp:rx
 dma1chan2    | in-use
 dma1chan3    | in-use
 dma1chan4    | in-use
 dma1chan5    | in-use

Drivers can implement custom dbg_summary_show to add extended information via
the summary file, like with the second patch for k3-udma (j721e-evm):

# cat /sys/kernel/debug/dmaengine/summary
dma0 (285c0000.dma-controller): number of channels: 24

dma1 (31150000.dma-controller): number of channels: 84
 dma1chan0    | 2b00000.mcasp:tx (MEM_TO_DEV, tchan16 [0x1010 -> 0xc400], PDMA[ ACC32 BURST ], TR mode)
 dma1chan1    | 2b00000.mcasp:rx (DEV_TO_MEM, rchan16 [0x4400 -> 0x9010], PDMA[ ACC32 BURST ], TR mode)
 dma1chan2    | 2ba0000.mcasp:tx (MEM_TO_DEV, tchan17 [0x1011 -> 0xc507], PDMA[ ACC32 BURST ], TR mode)
 dma1chan3    | 2ba0000.mcasp:rx (DEV_TO_MEM, rchan17 [0x4507 -> 0x9011], PDMA[ ACC32 BURST ], TR mode)
 dma1chan4    | in-use (MEM_TO_MEM, chan0 pair [0x1000 -> 0x9000], PSI-L Native, TR mode)
 dma1chan5    | in-use (MEM_TO_MEM, chan1 pair [0x1001 -> 0x9001], PSI-L Native, TR mode)
 dma1chan6    | in-use (MEM_TO_MEM, chan4 pair [0x1004 -> 0x9004], PSI-L Native, TR mode)
 dma1chan7    | in-use (MEM_TO_MEM, chan5 pair [0x1005 -> 0x9005], PSI-L Native, TR mode)

With the last patch the debugfs looks like this:
# ls -al /sys/kernel/debug/dmaengine/
total 0
drwxr-xr-x  4 root root 0 Jan  1 02:00 .
drwx------ 29 root root 0 Jan  1 02:00 ..
drwxr-xr-x  2 root root 0 Jan  1 02:00 285c0000.dma-controller
drwxr-xr-x  2 root root 0 Jan  1 02:00 31150000.dma-controller
-r--r--r--  1 root root 0 Jan  1 02:00 summary


Regards,
Peter
---
Peter Ujfalusi (3):
  dmaengine: Add basic debugfs support
  dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs
  dmaengine: Create debug directories for DMA devices

 drivers/dma/dmaengine.c   | 102 +++++++++++++++++++++++++++++++++++++-
 drivers/dma/dmaengine.h   |  16 ++++++
 drivers/dma/ti/k3-udma.c  |  63 +++++++++++++++++++++++
 include/linux/dmaengine.h |  14 +++++-
 4 files changed, 193 insertions(+), 2 deletions(-)

-- 
Peter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

[PATCH v5 1/3] dmaengine: Add basic debugfs support

[Peter Ujfalusi]

Via the /sys/kernel/debug/dmaengine/summary users can get information
about the DMA devices and the used channels.

Example output on am654-evm with audio using two channels and after running
dmatest on 4 channels:

dma0 (285c0000.dma-controller): number of channels: 96

dma1 (31150000.dma-controller): number of channels: 267
 dma1chan0    | 2b00000.mcasp:tx
 dma1chan1    | 2b00000.mcasp:rx
 dma1chan2    | in-use
 dma1chan3    | in-use
 dma1chan4    | in-use
 dma1chan5    | in-use

For slave channels we can show the device and the channel name a given
channel is requested.
For non slave devices the only information we know is that the channel is
in use.

DMA drivers can implement the optional dbg_summary_show callback to
provide controller specific information instead of the generic one.

It is easy to extend the generic dmaengine_summary_show() to print
additional information about the used channels.

I have taken the idea from gpiolib and clk subsystems.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
 drivers/dma/dmaengine.c   | 76 ++++++++++++++++++++++++++++++++++++++-
 include/linux/dmaengine.h | 13 ++++++-
 2 files changed, 87 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index c3b1283b6d31..509abc8e8378 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -58,6 +58,65 @@ static DEFINE_IDA(dma_ida);
 static LIST_HEAD(dma_device_list);
 static long dmaengine_ref_count;
 
+/* --- debugfs implementation --- */
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+static void dmaengine_dbg_summary_show(struct seq_file *s,
+				       struct dma_device *dma_dev)
+{
+	struct dma_chan *chan;
+
+	list_for_each_entry(chan, &dma_dev->channels, device_node) {
+		if (chan->client_count) {
+			seq_printf(s, " %-13s| %s", dma_chan_name(chan),
+				   chan->dbg_client_name ?: "in-use");
+
+			if (chan->router)
+				seq_printf(s, " (via router: %s)\n",
+					dev_name(chan->router->dev));
+			else
+				seq_puts(s, "\n");
+		}
+	}
+}
+
+static int dmaengine_summary_show(struct seq_file *s, void *data)
+{
+	struct dma_device *dma_dev = NULL;
+
+	mutex_lock(&dma_list_mutex);
+	list_for_each_entry(dma_dev, &dma_device_list, global_node) {
+		seq_printf(s, "dma%d (%s): number of channels: %u\n",
+			   dma_dev->dev_id, dev_name(dma_dev->dev),
+			   dma_dev->chancnt);
+
+		if (dma_dev->dbg_summary_show)
+			dma_dev->dbg_summary_show(s, dma_dev);
+		else
+			dmaengine_dbg_summary_show(s, dma_dev);
+
+		if (!list_is_last(&dma_dev->global_node, &dma_device_list))
+			seq_puts(s, "\n");
+	}
+	mutex_unlock(&dma_list_mutex);
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dmaengine_summary);
+
+static void __init dmaengine_debugfs_init(void)
+{
+	struct dentry *rootdir = debugfs_create_dir("dmaengine", NULL);
+
+	/* /sys/kernel/debug/dmaengine/summary */
+	debugfs_create_file("summary", 0444, rootdir, NULL,
+			    &dmaengine_summary_fops);
+}
+#else
+static inline void dmaengine_debugfs_init(void) { }
+#endif	/* DEBUG_FS */
+
 /* --- sysfs implementation --- */
 
 #define DMA_SLAVE_NAME	"slave"
@@ -760,6 +819,11 @@ struct dma_chan *dma_request_chan(struct device *dev, const char *name)
 		return chan ? chan : ERR_PTR(-EPROBE_DEFER);
 
 found:
+#ifdef CONFIG_DEBUG_FS
+	chan->dbg_client_name = kasprintf(GFP_KERNEL, "%s:%s", dev_name(dev),
+					  name);
+#endif
+
 	chan->name = kasprintf(GFP_KERNEL, "dma:%s", name);
 	if (!chan->name)
 		return chan;
@@ -837,6 +901,11 @@ void dma_release_channel(struct dma_chan *chan)
 		chan->name = NULL;
 		chan->slave = NULL;
 	}
+
+#ifdef CONFIG_DEBUG_FS
+	kfree(chan->dbg_client_name);
+	chan->dbg_client_name = NULL;
+#endif
 	mutex_unlock(&dma_list_mutex);
 }
 EXPORT_SYMBOL_GPL(dma_release_channel);
@@ -1559,6 +1628,11 @@ static int __init dma_bus_init(void)
 
 	if (err)
 		return err;
-	return class_register(&dma_devclass);
+
+	err = class_register(&dma_devclass);
+	if (!err)
+		dmaengine_debugfs_init();
+
+	return err;
 }
 arch_initcall(dma_bus_init);
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index d3672f065a64..72920b5cf2d7 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -300,6 +300,8 @@ struct dma_router {
  * @chan_id: channel ID for sysfs
  * @dev: class device for sysfs
  * @name: backlink name for sysfs
+ * @dbg_client_name: slave name for debugfs in format:
+ *	dev_name(requester's dev):channel name, for example: "2b00000.mcasp:tx"
  * @device_node: used to add this to the device chan list
  * @local: per-cpu pointer to a struct dma_chan_percpu
  * @client_count: how many clients are using this channel
@@ -318,6 +320,9 @@ struct dma_chan {
 	int chan_id;
 	struct dma_chan_dev *dev;
 	const char *name;
+#ifdef CONFIG_DEBUG_FS
+	char *dbg_client_name;
+#endif
 
 	struct list_head device_node;
 	struct dma_chan_percpu __percpu *local;
@@ -806,7 +811,9 @@ struct dma_filter {
  *     called and there are no further references to this structure. This
  *     must be implemented to free resources however many existing drivers
  *     do not and are therefore not safe to unbind while in use.
- *
+ * @dbg_summary_show: optional routine to show contents in debugfs; default code
+ *     will be used when this is omitted, but custom code can show extra,
+ *     controller specific information.
  */
 struct dma_device {
 	struct kref ref;
@@ -892,6 +899,10 @@ struct dma_device {
 					    struct dma_tx_state *txstate);
 	void (*device_issue_pending)(struct dma_chan *chan);
 	void (*device_release)(struct dma_device *dev);
+	/* debugfs support */
+#ifdef CONFIG_DEBUG_FS
+	void (*dbg_summary_show)(struct seq_file *s, struct dma_device *dev);
+#endif
 };
 
 static inline int dmaengine_slave_config(struct dma_chan *chan,
-- 
Peter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

[PATCH v5 2/3] dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs

[Peter Ujfalusi]

With the custom dbg_summary_show the driver can show useful information
about the used channels.

dma0 (285c0000.dma-controller): number of channels: 24

dma1 (31150000.dma-controller): number of channels: 84
 dma1chan0    | 2b00000.mcasp:tx (MEM_TO_DEV, tchan16 [0x1010 -> 0xc400], PDMA[ ACC32 BURST ], TR mode)
 dma1chan1    | 2b00000.mcasp:rx (DEV_TO_MEM, rchan16 [0x4400 -> 0x9010], PDMA[ ACC32 BURST ], TR mode)
 dma1chan2    | 2ba0000.mcasp:tx (MEM_TO_DEV, tchan17 [0x1011 -> 0xc507], PDMA[ ACC32 BURST ], TR mode)
 dma1chan3    | 2ba0000.mcasp:rx (DEV_TO_MEM, rchan17 [0x4507 -> 0x9011], PDMA[ ACC32 BURST ], TR mode)
 dma1chan4    | in-use (MEM_TO_MEM, chan0 pair [0x1000 -> 0x9000], PSI-L Native, TR mode)
 dma1chan5    | in-use (MEM_TO_MEM, chan1 pair [0x1001 -> 0x9001], PSI-L Native, TR mode)
 dma1chan6    | in-use (MEM_TO_MEM, chan4 pair [0x1004 -> 0x9004], PSI-L Native, TR mode)
 dma1chan7    | in-use (MEM_TO_MEM, chan5 pair [0x1005 -> 0x9005], PSI-L Native, TR mode)

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
 drivers/dma/ti/k3-udma.c | 63 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index 5e076e5680f4..a9c0251adf1a 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -3501,6 +3501,66 @@ static int udma_setup_rx_flush(struct udma_dev *ud)
 	return 0;
 }
 
+#ifdef CONFIG_DEBUG_FS
+static void udma_dbg_summary_show_chan(struct seq_file *s,
+				       struct dma_chan *chan)
+{
+	struct udma_chan *uc = to_udma_chan(chan);
+	struct udma_chan_config *ucc = &uc->config;
+
+	seq_printf(s, " %-13s| %s", dma_chan_name(chan),
+		   chan->dbg_client_name ?: "in-use");
+	seq_printf(s, " (%s, ", dmaengine_get_direction_text(uc->config.dir));
+
+	switch (uc->config.dir) {
+	case DMA_MEM_TO_MEM:
+		seq_printf(s, "chan%d pair [0x%04x -> 0x%04x], ", uc->tchan->id,
+			   ucc->src_thread, ucc->dst_thread);
+		break;
+	case DMA_DEV_TO_MEM:
+		seq_printf(s, "rchan%d [0x%04x -> 0x%04x], ", uc->rchan->id,
+			   ucc->src_thread, ucc->dst_thread);
+		break;
+	case DMA_MEM_TO_DEV:
+		seq_printf(s, "tchan%d [0x%04x -> 0x%04x], ", uc->tchan->id,
+			   ucc->src_thread, ucc->dst_thread);
+		break;
+	default:
+		seq_printf(s, ")\n");
+		return;
+	}
+
+	if (ucc->ep_type == PSIL_EP_NATIVE) {
+		seq_printf(s, "PSI-L Native");
+		if (ucc->metadata_size) {
+			seq_printf(s, "[%s", ucc->needs_epib ? " EPIB" : "");
+			if (ucc->psd_size)
+				seq_printf(s, " PSDsize:%u", ucc->psd_size);
+			seq_printf(s, " ]");
+		}
+	} else {
+		seq_printf(s, "PDMA");
+		if (ucc->enable_acc32 || ucc->enable_burst)
+			seq_printf(s, "[%s%s ]",
+				   ucc->enable_acc32 ? " ACC32" : "",
+				   ucc->enable_burst ? " BURST" : "");
+	}
+
+	seq_printf(s, ", %s)\n", ucc->pkt_mode ? "Packet mode" : "TR mode");
+}
+
+static void udma_dbg_summary_show(struct seq_file *s,
+				  struct dma_device *dma_dev)
+{
+	struct dma_chan *chan;
+
+	list_for_each_entry(chan, &dma_dev->channels, device_node) {
+		if (chan->client_count)
+			udma_dbg_summary_show_chan(s, chan);
+	}
+}
+#endif /* CONFIG_DEBUG_FS */
+
 #define TI_UDMAC_BUSWIDTHS	(BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
 				 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
 				 BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
@@ -3587,6 +3647,9 @@ static int udma_probe(struct platform_device *pdev)
 	ud->ddev.device_resume = udma_resume;
 	ud->ddev.device_terminate_all = udma_terminate_all;
 	ud->ddev.device_synchronize = udma_synchronize;
+#ifdef CONFIG_DEBUG_FS
+	ud->ddev.dbg_summary_show = udma_dbg_summary_show;
+#endif
 
 	ud->ddev.device_free_chan_resources = udma_free_chan_resources;
 	ud->ddev.src_addr_widths = TI_UDMAC_BUSWIDTHS;
-- 
Peter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

[PATCH v5 3/3] dmaengine: Create debug directories for DMA devices

[Peter Ujfalusi]

Create a placeholder directory for each registered DMA device.

DMA drivers can use the dmaengine_get_debugfs_root() call to get their
debugfs root and can populate with custom files to aim debugging.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
 drivers/dma/dmaengine.c   | 28 +++++++++++++++++++++++++++-
 drivers/dma/dmaengine.h   | 16 ++++++++++++++++
 include/linux/dmaengine.h |  1 +
 3 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 509abc8e8378..5a442752e07d 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -62,6 +62,22 @@ static long dmaengine_ref_count;
 #ifdef CONFIG_DEBUG_FS
 #include <linux/debugfs.h>
 
+static struct dentry *rootdir;
+
+static void dmaengine_debug_register(struct dma_device *dma_dev)
+{
+	dma_dev->dbg_dev_root = debugfs_create_dir(dev_name(dma_dev->dev),
+						   rootdir);
+	if (IS_ERR(dma_dev->dbg_dev_root))
+		dma_dev->dbg_dev_root = NULL;
+}
+
+static void dmaengine_debug_unregister(struct dma_device *dma_dev)
+{
+	debugfs_remove_recursive(dma_dev->dbg_dev_root);
+	dma_dev->dbg_dev_root = NULL;
+}
+
 static void dmaengine_dbg_summary_show(struct seq_file *s,
 				       struct dma_device *dma_dev)
 {
@@ -107,7 +123,7 @@ DEFINE_SHOW_ATTRIBUTE(dmaengine_summary);
 
 static void __init dmaengine_debugfs_init(void)
 {
-	struct dentry *rootdir = debugfs_create_dir("dmaengine", NULL);
+	rootdir = debugfs_create_dir("dmaengine", NULL);
 
 	/* /sys/kernel/debug/dmaengine/summary */
 	debugfs_create_file("summary", 0444, rootdir, NULL,
@@ -115,6 +131,12 @@ static void __init dmaengine_debugfs_init(void)
 }
 #else
 static inline void dmaengine_debugfs_init(void) { }
+static inline int dmaengine_debug_register(struct dma_device *dma_dev)
+{
+	return 0;
+}
+
+static inline void dmaengine_debug_unregister(struct dma_device *dma_dev) { }
 #endif	/* DEBUG_FS */
 
 /* --- sysfs implementation --- */
@@ -1265,6 +1287,8 @@ int dma_async_device_register(struct dma_device *device)
 	dma_channel_rebalance();
 	mutex_unlock(&dma_list_mutex);
 
+	dmaengine_debug_register(device);
+
 	return 0;
 
 err_out:
@@ -1298,6 +1322,8 @@ void dma_async_device_unregister(struct dma_device *device)
 {
 	struct dma_chan *chan, *n;
 
+	dmaengine_debug_unregister(device);
+
 	list_for_each_entry_safe(chan, n, &device->channels, device_node)
 		__dma_async_device_channel_unregister(device, chan);
 
diff --git a/drivers/dma/dmaengine.h b/drivers/dma/dmaengine.h
index e8a320c9e57c..1bfbd64b1371 100644
--- a/drivers/dma/dmaengine.h
+++ b/drivers/dma/dmaengine.h
@@ -182,4 +182,20 @@ dmaengine_desc_callback_valid(struct dmaengine_desc_callback *cb)
 struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
 struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
 
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+static inline struct dentry *
+dmaengine_get_debugfs_root(struct dma_device *dma_dev) {
+	return dma_dev->dbg_dev_root;
+}
+#else
+struct dentry;
+static inline struct dentry *
+dmaengine_get_debugfs_root(struct dma_device *dma_dev)
+{
+	return NULL;
+}
+#endif /* CONFIG_DEBUG_FS */
+
 #endif
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 72920b5cf2d7..21065c04c4ac 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -902,6 +902,7 @@ struct dma_device {
 	/* debugfs support */
 #ifdef CONFIG_DEBUG_FS
 	void (*dbg_summary_show)(struct seq_file *s, struct dma_device *dev);
+	struct dentry *dbg_dev_root;
 #endif
 };
 
-- 
Peter

Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki

Re: [PATCH v5 0/3] dmaengine: Initial debugfs support

[Vinod Koul]

On 06-03-20, 16:28, Peter Ujfalusi wrote:
> Hi,
> 
> Changes sicne v4:
> - Move the dmaengine_debugfs_init() from late_initcall to be called from
>   dma_bus_init to avoid races due to probe orders of drivers.
> - Separate patch to create DMA driver directories for debugfs
> 
> Changes since v3:
> - Create a directory for dmaengine and name the initial file as summary
> - Function to get the debugfs root for DMA drivers if they want to place files
> - Custom dbg_summary_show implementation for k3-udma
> 
> Changes since v2:
> - Use dma_chan_name() for printing the channel's name
> 
> Changes since v1:
> - Use much more simplified fops for the debugfs file (via DEFINE_SHOW_ATTRIBUTE)
> - do not allow modification to dma_device_list while the debugfs file is read
> - rename the slave_name to dbg_client_name (it is only for debugging)
> - print information about dma_router if it is used by the channel
> - Formating of the output slightly changed
> 
> The basic debugfs file (/sys/kernel/debug/dmaengine/summary) can be used to
> query basic information about the DMAengine usage (am654-evm):
> 
> # cat /sys/kernel/debug/dmaengine/summary
> dma0 (285c0000.dma-controller): number of channels: 96
> 
> dma1 (31150000.dma-controller): number of channels: 267
>  dma1chan0    | 2b00000.mcasp:tx
>  dma1chan1    | 2b00000.mcasp:rx
>  dma1chan2    | in-use
>  dma1chan3    | in-use
>  dma1chan4    | in-use
>  dma1chan5    | in-use
> 
> Drivers can implement custom dbg_summary_show to add extended information via
> the summary file, like with the second patch for k3-udma (j721e-evm):
> 
> # cat /sys/kernel/debug/dmaengine/summary
> dma0 (285c0000.dma-controller): number of channels: 24
> 
> dma1 (31150000.dma-controller): number of channels: 84
>  dma1chan0    | 2b00000.mcasp:tx (MEM_TO_DEV, tchan16 [0x1010 -> 0xc400], PDMA[ ACC32 BURST ], TR mode)
>  dma1chan1    | 2b00000.mcasp:rx (DEV_TO_MEM, rchan16 [0x4400 -> 0x9010], PDMA[ ACC32 BURST ], TR mode)
>  dma1chan2    | 2ba0000.mcasp:tx (MEM_TO_DEV, tchan17 [0x1011 -> 0xc507], PDMA[ ACC32 BURST ], TR mode)
>  dma1chan3    | 2ba0000.mcasp:rx (DEV_TO_MEM, rchan17 [0x4507 -> 0x9011], PDMA[ ACC32 BURST ], TR mode)
>  dma1chan4    | in-use (MEM_TO_MEM, chan0 pair [0x1000 -> 0x9000], PSI-L Native, TR mode)
>  dma1chan5    | in-use (MEM_TO_MEM, chan1 pair [0x1001 -> 0x9001], PSI-L Native, TR mode)
>  dma1chan6    | in-use (MEM_TO_MEM, chan4 pair [0x1004 -> 0x9004], PSI-L Native, TR mode)
>  dma1chan7    | in-use (MEM_TO_MEM, chan5 pair [0x1005 -> 0x9005], PSI-L Native, TR mode)
> 
> With the last patch the debugfs looks like this:
> # ls -al /sys/kernel/debug/dmaengine/
> total 0
> drwxr-xr-x  4 root root 0 Jan  1 02:00 .
> drwx------ 29 root root 0 Jan  1 02:00 ..
> drwxr-xr-x  2 root root 0 Jan  1 02:00 285c0000.dma-controller
> drwxr-xr-x  2 root root 0 Jan  1 02:00 31150000.dma-controller
> -r--r--r--  1 root root 0 Jan  1 02:00 summary

Applied, thanks

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~Vinod