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authorLinus Torvalds <torvalds@linux-foundation.org>2020-04-02 16:04:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-04-02 16:04:42 -0700
commite964f1e04a1ce562f0d748b29326244d3cb35ba4 (patch)
tree9f0afaef4b7e6a627595f27a1c5dc92c10e79103 /drivers/dma/dmaengine.c
parent5c8db3eb381745c010ba746373a279e92502bdc8 (diff)
parentcea582b5ee5645839650b6667335cfb40ec71c19 (diff)
Merge tag 'dmaengine-5.7-rc1' of git://git.infradead.org/users/vkoul/slave-dma
Pull dmaengine updates from Vinod Koul: "Core: - Some code cleanup and optimization in core by Andy - Debugfs support for displaying dmaengine channels by Peter Drivers: - New driver for uniphier-xdmac controller - Updates to stm32 dma, mdma and dmamux drivers and PM support - More updates to idxd drivers - Bunch of changes in tegra-apb driver and cleaning up of pm functions - Bunch of spelling fixes and Replace zero-length array patches - Shutdown hook for fsl-dpaa2-qdma driver - Support for interleaved transfers for ti-edma and virtualization support for k3-dma driver - Support for reset and updates in xilinx_dma driver - Improvements and locking updates in at_hdma driver" * tag 'dmaengine-5.7-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (89 commits) dt-bindings: dma: renesas,usb-dmac: add r8a77961 support dmaengine: uniphier-xdmac: Remove redandant error log for platform_get_irq dmaengine: tegra-apb: Improve DMA synchronization dmaengine: tegra-apb: Don't save/restore IRQ flags in interrupt handler dmaengine: tegra-apb: mark PM functions as __maybe_unused dmaengine: fix spelling mistake "exceds" -> "exceeds" dmaengine: sprd: Set request pending flag when DMA controller is active dmaengine: ppc4xx: Use scnprintf() for avoiding potential buffer overflow dmaengine: idxd: remove global token limit check dmaengine: idxd: reflect shadow copy of traffic class programming dmaengine: idxd: Merge definition of dsa_batch_desc into dsa_hw_desc dmaengine: Create debug directories for DMA devices dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs dmaengine: Add basic debugfs support dmaengine: fsl-dpaa2-qdma: remove set but not used variable 'dpaa2_qdma' dmaengine: ti: edma: fix null dereference because of a typo in pointer name dmaengine: fsl-dpaa2-qdma: Adding shutdown hook dmaengine: uniphier-xdmac: Add UniPhier external DMA controller driver dt-bindings: dmaengine: Add UniPhier external DMA controller bindings dmaengine: ti: k3-udma: Implement support for atype (for virtualization) ...
Diffstat (limited to 'drivers/dma/dmaengine.c')
-rw-r--r--drivers/dma/dmaengine.c102
1 files changed, 101 insertions, 1 deletions
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 17909fd1820f..4830ba658ce1 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -58,6 +58,87 @@ 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 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)
+{
+ 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)
+{
+ 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) { }
+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 --- */
#define DMA_SLAVE_NAME "slave"
@@ -760,6 +841,11 @@ 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 +923,11 @@ 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);
@@ -1196,6 +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:
@@ -1229,6 +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);
@@ -1559,6 +1654,11 @@ 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);