[alsa-devel] [PATCH 1/3] soundwire: add debugfs support
Pierre-Louis Bossart
pierre-louis.bossart at linux.intel.com
Sat Aug 10 00:43:39 CEST 2019
Add base debugfs mechanism for SoundWire bus by creating soundwire
root and master-N and slave-x hierarchy.
Also add SDW Slave SCP, DP0 and DP-N register debug file.
Registers not implemented will print as "XX"
Credits: this patch is based on an earlier internal contribution by
Vinod Koul, Sanyog Kale, Shreyas Nc and Hardik Shah.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
---
drivers/soundwire/Makefile | 5 ++
drivers/soundwire/bus.c | 6 ++
drivers/soundwire/bus.h | 24 ++++++
drivers/soundwire/bus_type.c | 3 +
drivers/soundwire/debugfs.c | 151 ++++++++++++++++++++++++++++++++++
drivers/soundwire/slave.c | 1 +
include/linux/soundwire/sdw.h | 4 +
7 files changed, 194 insertions(+)
create mode 100644 drivers/soundwire/debugfs.c
diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile
index fd99a831b92a..05d4cb9ef7d6 100644
--- a/drivers/soundwire/Makefile
+++ b/drivers/soundwire/Makefile
@@ -5,6 +5,11 @@
#Bus Objs
soundwire-bus-objs := bus_type.o bus.o slave.o mipi_disco.o stream.o
+
+ifdef CONFIG_DEBUG_FS
+soundwire-bus-objs += debugfs.o
+endif
+
obj-$(CONFIG_SOUNDWIRE_BUS) += soundwire-bus.o
#Cadence Objs
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index 49f64b2115b9..89d5f1537d9b 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -49,6 +49,8 @@ int sdw_add_bus_master(struct sdw_bus *bus)
}
}
+ bus->debugfs = sdw_bus_debugfs_init(bus);
+
/*
* Device numbers in SoundWire are 0 through 15. Enumeration device
* number (0), Broadcast device number (15), Group numbers (12 and
@@ -109,6 +111,8 @@ static int sdw_delete_slave(struct device *dev, void *data)
struct sdw_slave *slave = dev_to_sdw_dev(dev);
struct sdw_bus *bus = slave->bus;
+ sdw_slave_debugfs_exit(slave->debugfs);
+
mutex_lock(&bus->bus_lock);
if (slave->dev_num) /* clear dev_num if assigned */
@@ -130,6 +134,8 @@ static int sdw_delete_slave(struct device *dev, void *data)
void sdw_delete_bus_master(struct sdw_bus *bus)
{
device_for_each_child(bus->dev, NULL, sdw_delete_slave);
+
+ sdw_bus_debugfs_exit(bus->debugfs);
}
EXPORT_SYMBOL(sdw_delete_bus_master);
diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h
index 3048ca153f22..648436a995a3 100644
--- a/drivers/soundwire/bus.h
+++ b/drivers/soundwire/bus.h
@@ -18,6 +18,30 @@ static inline int sdw_acpi_find_slaves(struct sdw_bus *bus)
void sdw_extract_slave_id(struct sdw_bus *bus,
u64 addr, struct sdw_slave_id *id);
+#ifdef CONFIG_DEBUG_FS
+struct dentry *sdw_bus_debugfs_init(struct sdw_bus *bus);
+void sdw_bus_debugfs_exit(struct dentry *d);
+struct dentry *sdw_slave_debugfs_init(struct sdw_slave *slave);
+void sdw_slave_debugfs_exit(struct dentry *d);
+void sdw_debugfs_init(void);
+void sdw_debugfs_exit(void);
+#else
+static inline struct dentry *sdw_bus_debugfs_init(struct sdw_bus *bus)
+{ return NULL; }
+
+static inline void sdw_bus_debugfs_exit(struct dentry *d) {}
+
+static inline struct dentry *sdw_slave_debugfs_init(struct sdw_slave *slave)
+{ return NULL; }
+
+static inline void sdw_slave_debugfs_exit(struct dentry *d) {}
+
+static inline void sdw_debugfs_init(void) {}
+
+static inline void sdw_debugfs_exit(void) {}
+
+#endif
+
enum {
SDW_MSG_FLAG_READ = 0,
SDW_MSG_FLAG_WRITE,
diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c
index 2655602f0cfb..4a465f55039f 100644
--- a/drivers/soundwire/bus_type.c
+++ b/drivers/soundwire/bus_type.c
@@ -6,6 +6,7 @@
#include <linux/pm_domain.h>
#include <linux/soundwire/sdw.h>
#include <linux/soundwire/sdw_type.h>
+#include "bus.h"
/**
* sdw_get_device_id - find the matching SoundWire device id
@@ -177,11 +178,13 @@ EXPORT_SYMBOL_GPL(sdw_unregister_driver);
static int __init sdw_bus_init(void)
{
+ sdw_debugfs_init();
return bus_register(&sdw_bus_type);
}
static void __exit sdw_bus_exit(void)
{
+ sdw_debugfs_exit();
bus_unregister(&sdw_bus_type);
}
diff --git a/drivers/soundwire/debugfs.c b/drivers/soundwire/debugfs.c
new file mode 100644
index 000000000000..200eb98ec99b
--- /dev/null
+++ b/drivers/soundwire/debugfs.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright(c) 2017-2019 Intel Corporation.
+
+#include <linux/device.h>
+#include <linux/debugfs.h>
+#include <linux/mod_devicetable.h>
+#include <linux/slab.h>
+#include <linux/soundwire/sdw.h>
+#include <linux/soundwire/sdw_registers.h>
+#include "bus.h"
+
+static struct dentry *sdw_debugfs_root;
+
+struct dentry *sdw_bus_debugfs_init(struct sdw_bus *bus)
+{
+ char name[16];
+
+ if (!sdw_debugfs_root)
+ return NULL;
+
+ /* create the debugfs master-N */
+ snprintf(name, sizeof(name), "master-%d", bus->link_id);
+ return debugfs_create_dir(name, sdw_debugfs_root);
+}
+
+void sdw_bus_debugfs_exit(struct dentry *d)
+{
+ debugfs_remove_recursive(d);
+}
+
+#define RD_BUF (3 * PAGE_SIZE)
+
+static ssize_t sdw_sprintf(struct sdw_slave *slave,
+ char *buf, size_t pos, unsigned int reg)
+{
+ int value;
+
+ value = sdw_read(slave, reg);
+
+ if (value < 0)
+ return scnprintf(buf + pos, RD_BUF - pos, "%3x\tXX\n", reg);
+ else
+ return scnprintf(buf + pos, RD_BUF - pos,
+ "%3x\t%2x\n", reg, value);
+}
+
+static int sdw_slave_reg_show(struct seq_file *s_file, void *data)
+{
+ struct sdw_slave *slave = s_file->private;
+ char *buf;
+ ssize_t ret;
+ int i, j;
+
+ buf = kzalloc(RD_BUF, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ ret = scnprintf(buf, RD_BUF, "Register Value\n");
+
+ /* DP0 non-banked registers */
+ ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP0\n");
+ for (i = SDW_DP0_INT; i <= SDW_DP0_PREPARECTRL; i++)
+ ret += sdw_sprintf(slave, buf, ret, i);
+
+ /* DP0 Bank 0 registers */
+ ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n");
+ ret += sdw_sprintf(slave, buf, ret, SDW_DP0_CHANNELEN);
+ for (i = SDW_DP0_SAMPLECTRL1; i <= SDW_DP0_LANECTRL; i++)
+ ret += sdw_sprintf(slave, buf, ret, i);
+
+ /* DP0 Bank 1 registers */
+ ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n");
+ ret += sdw_sprintf(slave, buf, ret,
+ SDW_DP0_CHANNELEN + SDW_BANK1_OFFSET);
+ for (i = SDW_DP0_SAMPLECTRL1 + SDW_BANK1_OFFSET;
+ i <= SDW_DP0_LANECTRL + SDW_BANK1_OFFSET; i++)
+ ret += sdw_sprintf(slave, buf, ret, i);
+
+ /* SCP registers */
+ ret += scnprintf(buf + ret, RD_BUF - ret, "\nSCP\n");
+ for (i = SDW_SCP_INT1; i <= SDW_SCP_BANKDELAY; i++)
+ ret += sdw_sprintf(slave, buf, ret, i);
+ for (i = SDW_SCP_DEVID_0; i <= SDW_SCP_DEVID_5; i++)
+ ret += sdw_sprintf(slave, buf, ret, i);
+
+ /*
+ * SCP Bank 0/1 registers are read-only and cannot be
+ * retrieved from the Slave. The Master typically keeps track
+ * of the current frame size so the information can be found
+ * in other places
+ */
+
+ /* DP1..14 registers */
+ for (i = 1; SDW_VALID_PORT_RANGE(i); i++) {
+
+ /* DPi registers */
+ ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP%d\n", i);
+ for (j = SDW_DPN_INT(i); j <= SDW_DPN_PREPARECTRL(i); j++)
+ ret += sdw_sprintf(slave, buf, ret, j);
+
+ /* DPi Bank0 registers */
+ ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n");
+ for (j = SDW_DPN_CHANNELEN_B0(i);
+ j <= SDW_DPN_LANECTRL_B0(i); j++)
+ ret += sdw_sprintf(slave, buf, ret, j);
+
+ /* DPi Bank1 registers */
+ ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n");
+ for (j = SDW_DPN_CHANNELEN_B1(i);
+ j <= SDW_DPN_LANECTRL_B1(i); j++)
+ ret += sdw_sprintf(slave, buf, ret, j);
+ }
+
+ seq_printf(s_file, "%s", buf);
+ kfree(buf);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(sdw_slave_reg);
+
+struct dentry *sdw_slave_debugfs_init(struct sdw_slave *slave)
+{
+ struct dentry *master;
+ struct dentry *d;
+ char name[32];
+
+ master = slave->bus->debugfs;
+
+ /* create the debugfs slave-name */
+ snprintf(name, sizeof(name), "%s", dev_name(&slave->dev));
+ d = debugfs_create_dir(name, master);
+
+ debugfs_create_file("registers", 0400, d, slave, &sdw_slave_reg_fops);
+
+ return d;
+}
+
+void sdw_slave_debugfs_exit(struct dentry *d)
+{
+ debugfs_remove_recursive(d);
+}
+
+void sdw_debugfs_init(void)
+{
+ sdw_debugfs_root = debugfs_create_dir("soundwire", NULL);
+}
+
+void sdw_debugfs_exit(void)
+{
+ debugfs_remove_recursive(sdw_debugfs_root);
+}
diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c
index f39a5815e25d..34d8bb995f45 100644
--- a/drivers/soundwire/slave.c
+++ b/drivers/soundwire/slave.c
@@ -56,6 +56,7 @@ static int sdw_slave_add(struct sdw_bus *bus,
mutex_unlock(&bus->bus_lock);
put_device(&slave->dev);
}
+ slave->debugfs = sdw_slave_debugfs_init(slave);
return ret;
}
diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h
index 3b231472464a..a49028e9d666 100644
--- a/include/linux/soundwire/sdw.h
+++ b/include/linux/soundwire/sdw.h
@@ -544,6 +544,7 @@ struct sdw_slave_ops {
* @bus: Bus handle
* @ops: Slave callback ops
* @prop: Slave properties
+ * @debugfs: Slave debugfs
* @node: node for bus list
* @port_ready: Port ready completion flag for each Slave port
* @dev_num: Device Number assigned by Bus
@@ -555,6 +556,7 @@ struct sdw_slave {
struct sdw_bus *bus;
const struct sdw_slave_ops *ops;
struct sdw_slave_prop prop;
+ struct dentry *debugfs;
struct list_head node;
struct completion *port_ready;
u16 dev_num;
@@ -731,6 +733,7 @@ struct sdw_master_ops {
* @m_rt_list: List of Master instance of all stream(s) running on Bus. This
* is used to compute and program bus bandwidth, clock, frame shape,
* transport and port parameters
+ * @debugfs: Bus debugfs
* @defer_msg: Defer message
* @clk_stop_timeout: Clock stop timeout computed
* @bank_switch_timeout: Bank switch timeout computed
@@ -750,6 +753,7 @@ struct sdw_bus {
struct sdw_bus_params params;
struct sdw_master_prop prop;
struct list_head m_rt_list;
+ struct dentry *debugfs;
struct sdw_defer defer_msg;
unsigned int clk_stop_timeout;
u32 bank_switch_timeout;
--
2.20.1
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