[PATCH v5 10/15] soundwire: Add sysfs for SoundWire DisCo properties

From: Vinod Koul
Date: Wed Dec 06 2017 - 10:47:05 EST


It helps to read the properties for understanding and debugging
systems, so add sysfs files for SoundWire DisCo properties.

TODO: Add ABI files for sysfs

Signed-off-by: Sanyog Kale <sanyog.r.kale@xxxxxxxxx>
Signed-off-by: Vinod Koul <vinod.koul@xxxxxxxxx>
---
drivers/soundwire/Makefile | 2 +-
drivers/soundwire/bus.c | 3 +
drivers/soundwire/bus.h | 2 +
drivers/soundwire/slave.c | 1 +
drivers/soundwire/sysfs.c | 343 ++++++++++++++++++++++++++++++++++++++++++
include/linux/soundwire/sdw.h | 13 ++
6 files changed, 363 insertions(+), 1 deletion(-)
create mode 100644 drivers/soundwire/sysfs.c

diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile
index bcde0d26524c..67dc7b546258 100644
--- a/drivers/soundwire/Makefile
+++ b/drivers/soundwire/Makefile
@@ -3,5 +3,5 @@
#

#Bus Objs
-soundwire-bus-objs := bus_type.o bus.o slave.o mipi_disco.o
+soundwire-bus-objs := bus_type.o bus.o slave.o mipi_disco.o sysfs.o
obj-$(CONFIG_SOUNDWIRE_BUS) += soundwire-bus.o
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index bf68faface75..94245d70c913 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -41,6 +41,8 @@ int sdw_add_bus_master(struct sdw_bus *bus)
}
}

+ sdw_sysfs_bus_init(bus);
+
/*
* Device numbers in SoundWire are 0 thru 15. Enumeration device
* number (0), Broadcast device number (15), Group numbers (12 and
@@ -105,6 +107,7 @@ static int sdw_delete_slave(struct device *dev, void *data)
*/
void sdw_delete_bus_master(struct sdw_bus *bus)
{
+ sdw_sysfs_bus_exit(bus);
device_for_each_child(bus->dev, NULL, sdw_delete_slave);
}
EXPORT_SYMBOL(sdw_delete_bus_master);
diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h
index 345c34d697e9..d9fbb9a991ae 100644
--- a/drivers/soundwire/bus.h
+++ b/drivers/soundwire/bus.h
@@ -16,6 +16,8 @@ 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);

+extern const struct attribute_group *sdw_slave_dev_attr_groups[];
+
enum {
SDW_MSG_FLAG_READ = 0,
SDW_MSG_FLAG_WRITE,
diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c
index 2b88396bec66..ce7aa5ec609e 100644
--- a/drivers/soundwire/slave.c
+++ b/drivers/soundwire/slave.c
@@ -34,6 +34,7 @@ static int sdw_slave_add(struct sdw_bus *bus,
id->class_id, id->unique_id);

slave->dev.release = sdw_slave_release;
+ slave->dev.groups = sdw_slave_dev_attr_groups;
slave->dev.bus = &sdw_bus_type;
slave->bus = bus;
slave->status = SDW_SLAVE_UNATTACHED;
diff --git a/drivers/soundwire/sysfs.c b/drivers/soundwire/sysfs.c
new file mode 100644
index 000000000000..9e9093c17dcf
--- /dev/null
+++ b/drivers/soundwire/sysfs.c
@@ -0,0 +1,343 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2015-17 Intel Corporation.
+
+#include <linux/device.h>
+#include <linux/mod_devicetable.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/soundwire/sdw.h>
+#include <linux/soundwire/sdw_type.h>
+#include "bus.h"
+
+/*
+ * The sysfs for properties reflects the MIPI description as given
+ * in the MIPI DisCo spec
+ *
+ * Base file is:
+ * properties
+ * |---- interface-revision
+ * |---- master-count
+ * |---- link-N
+ * |---- clock-stop-modes
+ * |---- max-clock-frequency
+ * |---- clock-frequencies
+ * |---- default-frame-rows
+ * |---- default-frame-cols
+ * |---- dynamic-frame-shape
+ * |---- command-error-threshold
+ */
+
+struct sdw_master_sysfs {
+ struct kobject kobj;
+ struct sdw_bus *bus;
+};
+
+struct sdw_prop_attribute {
+ struct attribute attr;
+ ssize_t (*show)(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf);
+};
+
+static ssize_t sdw_prop_attr_show(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ struct sdw_prop_attribute *prop_attr =
+ container_of(attr, struct sdw_prop_attribute, attr);
+ struct sdw_master_sysfs *master =
+ container_of(kobj, struct sdw_master_sysfs, kobj);
+
+ if (!prop_attr->show)
+ return -EIO;
+
+ return prop_attr->show(master->bus, prop_attr, buf);
+}
+
+static const struct sysfs_ops sdw_prop_sysfs_ops = {
+ .show = sdw_prop_attr_show,
+};
+
+static void prop_release(struct kobject *kobj)
+{
+ struct sdw_master_sysfs *master =
+ container_of(kobj, struct sdw_master_sysfs, kobj);
+
+ kfree(master);
+}
+
+static struct kobj_type sdw_master_prop_ktype = {
+ .release = prop_release,
+ .sysfs_ops = &sdw_prop_sysfs_ops,
+};
+
+
+#define MASTER_ATTR(_name) \
+ struct sdw_prop_attribute master_attr_##_name = __ATTR_RO(_name)
+
+static ssize_t revision_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", bus->prop.revision);
+}
+
+static ssize_t count_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", bus->prop.master_count);
+}
+
+static ssize_t clock_stop_modes_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", bus->prop.clk_stop_mode);
+}
+
+static ssize_t max_clock_frequency_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", bus->prop.max_freq);
+}
+
+static ssize_t clock_frequencies_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ ssize_t size = 0;
+ int i;
+
+ for (i = 0; i < bus->prop.num_freq; i++)
+ size += sprintf(buf + size, "%8d\n", bus->prop.freq[i]);
+
+ return size;
+}
+
+static ssize_t clock_gears_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ ssize_t size = 0;
+ int i;
+
+ for (i = 0; i < bus->prop.num_clk_gears; i++)
+ size += sprintf(buf + size, "%8d\n", bus->prop.clk_gears[i]);
+
+ return size;
+}
+
+static ssize_t default_frame_rows_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", bus->prop.default_row);
+}
+
+static ssize_t default_frame_cols_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", bus->prop.default_col);
+}
+
+static ssize_t dynamic_frame_shape_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", bus->prop.dynamic_frame);
+}
+
+static ssize_t command_error_threshold_show(struct sdw_bus *bus,
+ struct sdw_prop_attribute *attr, char *buf)
+{
+ return sprintf(buf, "0x%08x\n", bus->prop.err_threshold);
+}
+
+static MASTER_ATTR(revision);
+static MASTER_ATTR(count);
+static MASTER_ATTR(clock_stop_modes);
+static MASTER_ATTR(max_clock_frequency);
+static MASTER_ATTR(clock_frequencies);
+static MASTER_ATTR(clock_gears);
+static MASTER_ATTR(default_frame_rows);
+static MASTER_ATTR(default_frame_cols);
+static MASTER_ATTR(dynamic_frame_shape);
+static MASTER_ATTR(command_error_threshold);
+
+static struct attribute *master_node_attrs[] = {
+ &master_attr_revision.attr,
+ &master_attr_count.attr,
+ &master_attr_clock_stop_modes.attr,
+ &master_attr_max_clock_frequency.attr,
+ &master_attr_clock_frequencies.attr,
+ &master_attr_clock_gears.attr,
+ &master_attr_default_frame_rows.attr,
+ &master_attr_default_frame_cols.attr,
+ &master_attr_dynamic_frame_shape.attr,
+ &master_attr_command_error_threshold.attr,
+ NULL,
+};
+
+static const struct attribute_group sdw_master_node_group = {
+ .attrs = master_node_attrs,
+};
+
+int sdw_sysfs_bus_init(struct sdw_bus *bus)
+{
+ struct kset *sdw_bus_kset;
+ struct sdw_master_sysfs *master;
+ int err;
+
+ if (bus->sysfs) {
+ dev_err(bus->dev, "SDW sysfs is already initialized\n");
+ return -EIO;
+ }
+
+ sdw_bus_kset = bus_get_kset(&sdw_bus_type);
+
+ master = bus->sysfs = kzalloc(sizeof(*master), GFP_KERNEL);
+ if (!master)
+ return -ENOMEM;
+
+ err = kobject_init_and_add(&master->kobj,
+ &sdw_master_prop_ktype, &sdw_bus_kset->kobj,
+ "mipi-properties-link%d", bus->link_id);
+ if (err < 0)
+ return err;
+
+ master->bus = bus;
+
+ err = sysfs_create_group(&master->kobj, &sdw_master_node_group);
+ if (err < 0) {
+ kobject_put(&master->kobj);
+ return err;
+ }
+
+ kobject_uevent(&master->kobj, KOBJ_CHANGE);
+ return 0;
+}
+
+void sdw_sysfs_bus_exit(struct sdw_bus *bus)
+{
+ struct sdw_master_sysfs *master = bus->sysfs;
+
+ if (!master)
+ return;
+
+ kobject_put(&master->kobj);
+ bus->sysfs = NULL;
+}
+
+/*
+ * Slave sysfs
+ */
+
+/*
+ * The sysfs for Slave reflects the MIPI description as given
+ * in the MIPI DisCo spec
+ *
+ * Base file is device
+ * |---- mipi_revision
+ * |---- wake_capable
+ * |---- test_mode_capable
+ * |---- simple_clk_stop_capable
+ * |---- clk_stop_timeout
+ * |---- ch_prep_timeout
+ * |---- reset_behave
+ * |---- high_PHY_capable
+ * |---- paging_support
+ * |---- bank_delay_support
+ * |---- p15_behave
+ * |---- master_count
+ * |---- source_ports
+ * |---- sink_ports
+ * |---- dp0
+ * |---- max_word
+ * |---- min_word
+ * |---- words
+ * |---- flow_controlled
+ * |---- simple_ch_prep_sm
+ * |---- device_interrupts
+ * |---- dpN
+ * |---- max_word
+ * |---- min_word
+ * |---- words
+ * |---- type
+ * |---- max_grouping
+ * |---- simple_ch_prep_sm
+ * |---- ch_prep_timeout
+ * |---- device_interrupts
+ * |---- max_ch
+ * |---- min_ch
+ * |---- ch
+ * |---- ch_combinations
+ * |---- modes
+ * |---- max_async_buffer
+ * |---- block_pack_mode
+ * |---- port_encoding
+ * |---- bus_min_freq
+ * |---- bus_max_freq
+ * |---- bus_freq
+ * |---- max_freq
+ * |---- min_freq
+ * |---- freq
+ * |---- prep_ch_behave
+ * |---- glitchless
+ *
+ */
+struct sdw_slave_sysfs {
+ struct sdw_slave *slave;
+};
+
+#define SLAVE_ATTR(type) \
+static ssize_t type##_show(struct device *dev, \
+ struct device_attribute *attr, char *buf) \
+{ \
+ struct sdw_slave *slave = dev_to_sdw_dev(dev); \
+ return sprintf(buf, "0x%x\n", slave->prop.type); \
+} \
+static DEVICE_ATTR_RO(type)
+
+SLAVE_ATTR(mipi_revision);
+SLAVE_ATTR(wake_capable);
+SLAVE_ATTR(test_mode_capable);
+SLAVE_ATTR(clk_stop_mode1);
+SLAVE_ATTR(simple_clk_stop_capable);
+SLAVE_ATTR(clk_stop_timeout);
+SLAVE_ATTR(ch_prep_timeout);
+SLAVE_ATTR(reset_behave);
+SLAVE_ATTR(high_PHY_capable);
+SLAVE_ATTR(paging_support);
+SLAVE_ATTR(bank_delay_support);
+SLAVE_ATTR(p15_behave);
+SLAVE_ATTR(master_count);
+SLAVE_ATTR(source_ports);
+
+static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct sdw_slave *slave = dev_to_sdw_dev(dev);
+
+ return sdw_slave_modalias(slave, buf, 256);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static struct attribute *slave_dev_attrs[] = {
+ &dev_attr_mipi_revision.attr,
+ &dev_attr_wake_capable.attr,
+ &dev_attr_test_mode_capable.attr,
+ &dev_attr_clk_stop_mode1.attr,
+ &dev_attr_simple_clk_stop_capable.attr,
+ &dev_attr_clk_stop_timeout.attr,
+ &dev_attr_ch_prep_timeout.attr,
+ &dev_attr_reset_behave.attr,
+ &dev_attr_high_PHY_capable.attr,
+ &dev_attr_paging_support.attr,
+ &dev_attr_bank_delay_support.attr,
+ &dev_attr_p15_behave.attr,
+ &dev_attr_master_count.attr,
+ &dev_attr_source_ports.attr,
+ &dev_attr_modalias.attr,
+ NULL,
+};
+
+static struct attribute_group sdw_slave_dev_attr_group = {
+ .attrs = slave_dev_attrs,
+};
+
+const struct attribute_group *sdw_slave_dev_attr_groups[] = {
+ &sdw_slave_dev_attr_group,
+ NULL
+};
diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h
index e752db72a045..fce502d08fef 100644
--- a/include/linux/soundwire/sdw.h
+++ b/include/linux/soundwire/sdw.h
@@ -308,6 +308,15 @@ int sdw_master_read_prop(struct sdw_bus *bus);
int sdw_slave_read_prop(struct sdw_slave *slave);

/*
+ * SDW sysfs APIs
+ */
+struct sdw_slave_sysfs;
+struct sdw_master_sysfs;
+
+int sdw_sysfs_bus_init(struct sdw_bus *bus);
+void sdw_sysfs_bus_exit(struct sdw_bus *bus);
+
+/*
* SDW Slave Structures and APIs
*/

@@ -363,6 +372,7 @@ struct sdw_slave_ops {
* @bus: Bus handle
* @ops: Slave callback ops
* @prop: Slave properties
+ * @sysfs: Sysfs interface
* @node: node for bus list
* @port_ready: Port ready completion flag for each Slave port
* @dev_num: Device Number assigned by Bus
@@ -374,6 +384,7 @@ struct sdw_slave {
struct sdw_bus *bus;
const struct sdw_slave_ops *ops;
struct sdw_slave_prop prop;
+ struct sdw_slave_sysfs *sysfs;
struct list_head node;
struct completion *port_ready;
u16 dev_num;
@@ -453,6 +464,7 @@ struct sdw_master_ops {
* @msg_lock: message lock
* @ops: Master callback ops
* @prop: Master properties
+ * @sysfs: Bus sysfs
* @defer_msg: Defer message
* @clk_stop_timeout: Clock stop timeout computed
*/
@@ -465,6 +477,7 @@ struct sdw_bus {
struct mutex msg_lock;
const struct sdw_master_ops *ops;
struct sdw_master_prop prop;
+ struct sdw_master_sysfs *sysfs;
struct sdw_defer defer_msg;
unsigned int clk_stop_timeout;
};
--
2.7.4