From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
In the existing SoundWire code, Master Devices are not explicitly represented - only SoundWire Slave Devices are exposed (the use of capital letters follows the SoundWire specification conventions).
With the existing code, the bus is handled without using a proper device, and bus->dev typically points to a platform device. The right thing to do as discussed in multiple reviews is use a device for each bus.
The sdw_master_device addition is done with minimal internal plumbing and not exposed externally. The existing API based on sdw_bus_master_add() and sdw_bus_master_delete() will deal with the sdw_master_device life cycle, which minimizes changes to existing drivers.
Note that the Intel code will be modified in follow-up patches (no impact on any platform since the connection with ASoC is not supported upstream so far).
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/Makefile | 2 +- drivers/soundwire/bus.c | 14 ++++-- drivers/soundwire/bus.h | 3 ++ drivers/soundwire/intel.c | 1 - drivers/soundwire/master.c | 81 +++++++++++++++++++++++++++++++++++ drivers/soundwire/qcom.c | 1 - include/linux/soundwire/sdw.h | 17 +++++++- 7 files changed, 112 insertions(+), 7 deletions(-) create mode 100644 drivers/soundwire/master.c
diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile index e2cdff990e9f..7319918e0aec 100644 --- a/drivers/soundwire/Makefile +++ b/drivers/soundwire/Makefile @@ -4,7 +4,7 @@ #
#Bus Objs -soundwire-bus-objs := bus_type.o bus.o slave.o mipi_disco.o stream.o +soundwire-bus-objs := bus_type.o bus.o master.o slave.o mipi_disco.o stream.o obj-$(CONFIG_SOUNDWIRE) += soundwire-bus.o
ifdef CONFIG_DEBUG_FS diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 2d24f183061d..c31a1c2788a9 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -37,14 +37,21 @@ int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent, struct sdw_master_prop *prop = NULL; int ret;
- if (!bus->dev) { - pr_err("SoundWire bus has no device\n"); + if (!parent) { + pr_err("SoundWire parent device is not set\n"); return -ENODEV; }
ret = sdw_get_id(bus); if (ret) { - dev_err(bus->dev, "Failed to get bus id\n"); + dev_err(parent, "Failed to get bus id\n"); + return ret; + } + + ret = sdw_master_device_add(bus, parent, fwnode); + if (ret) { + dev_err(parent, "Failed to add master device at link %d\n", + bus->link_id); return ret; }
@@ -161,6 +168,7 @@ static int sdw_delete_slave(struct device *dev, void *data) void sdw_bus_master_delete(struct sdw_bus *bus) { device_for_each_child(bus->dev, NULL, sdw_delete_slave); + sdw_master_device_del(bus);
sdw_bus_debugfs_exit(bus); ida_free(&sdw_ida, bus->id); diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h index 204204a26db8..93ab0234a491 100644 --- a/drivers/soundwire/bus.h +++ b/drivers/soundwire/bus.h @@ -19,6 +19,9 @@ static inline int sdw_acpi_find_slaves(struct sdw_bus *bus) int sdw_of_find_slaves(struct sdw_bus *bus); void sdw_extract_slave_id(struct sdw_bus *bus, u64 addr, struct sdw_slave_id *id); +int sdw_master_device_add(struct sdw_bus *bus, struct device *parent, + struct fwnode_handle *fwnode); +int sdw_master_device_del(struct sdw_bus *bus);
#ifdef CONFIG_DEBUG_FS void sdw_bus_debugfs_init(struct sdw_bus *bus); diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 210459390046..3562f2106e30 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1099,7 +1099,6 @@ static int intel_probe(struct platform_device *pdev) sdw->cdns.registers = sdw->link_res->registers; sdw->cdns.instance = sdw->instance; sdw->cdns.msg_count = 0; - sdw->cdns.bus.dev = &pdev->dev; sdw->cdns.bus.link_id = pdev->id;
sdw_cdns_probe(&sdw->cdns); diff --git a/drivers/soundwire/master.c b/drivers/soundwire/master.c new file mode 100644 index 000000000000..6be0a027def7 --- /dev/null +++ b/drivers/soundwire/master.c @@ -0,0 +1,81 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright(c) 2019-2020 Intel Corporation. + +#include <linux/device.h> +#include <linux/acpi.h> +#include <linux/soundwire/sdw.h> +#include <linux/soundwire/sdw_type.h> +#include "bus.h" + +static void sdw_master_device_release(struct device *dev) +{ + struct sdw_master_device *md = dev_to_sdw_master_device(dev); + + kfree(md); +} + +struct device_type sdw_master_type = { + .name = "soundwire_master", + .release = sdw_master_device_release, +}; + +/** + * sdw_master_device_add() - create a Linux Master Device representation. + * @bus: SDW bus instance + * @parent: parent device + * @fwnode: firmware node handle + */ +int sdw_master_device_add(struct sdw_bus *bus, struct device *parent, + struct fwnode_handle *fwnode) +{ + struct sdw_master_device *md; + int ret; + + if (!parent) + return -EINVAL; + + md = kzalloc(sizeof(*md), GFP_KERNEL); + if (!md) + return -ENOMEM; + + md->dev.bus = &sdw_bus_type; + md->dev.type = &sdw_master_type; + md->dev.parent = parent; + md->dev.of_node = parent->of_node; + md->dev.fwnode = fwnode; + md->dev.dma_mask = parent->dma_mask; + + dev_set_name(&md->dev, "sdw-master-%d", bus->id); + + ret = device_register(&md->dev); + if (ret) { + dev_err(parent, "Failed to add master: ret %d\n", ret); + /* + * On err, don't free but drop ref as this will be freed + * when release method is invoked. + */ + put_device(&md->dev); + goto device_register_err; + } + + /* add shortcuts to improve code readability/compactness */ + md->bus = bus; + bus->dev = &md->dev; + bus->md = md; + +device_register_err: + return ret; +} + +/** + * sdw_master_device_del() - delete a Linux Master Device representation. + * @bus: bus handle + * + * This function is the dual of sdw_master_device_add() + */ +int sdw_master_device_del(struct sdw_bus *bus) +{ + device_unregister(bus->dev); + + return 0; +} diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c index 401811d6627e..1c335ab1cd3f 100644 --- a/drivers/soundwire/qcom.c +++ b/drivers/soundwire/qcom.c @@ -784,7 +784,6 @@ static int qcom_swrm_probe(struct platform_device *pdev) mutex_init(&ctrl->port_lock); INIT_WORK(&ctrl->slave_work, qcom_swrm_slave_wq);
- ctrl->bus.dev = dev; ctrl->bus.ops = &qcom_swrm_ops; ctrl->bus.port_ops = &qcom_swrm_port_ops; ctrl->bus.compute_params = &qcom_swrm_compute_params; diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index a32cb26f1815..7658d9698dd5 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -632,6 +632,19 @@ struct sdw_slave {
#define dev_to_sdw_dev(_dev) container_of(_dev, struct sdw_slave, dev)
+/** + * struct sdw_master_device - SoundWire 'Master Device' representation + * @dev: Linux device for this Master + * @bus: Bus handle shortcut + */ +struct sdw_master_device { + struct device dev; + struct sdw_bus *bus; +}; + +#define dev_to_sdw_master_device(d) \ + container_of(d, struct sdw_master_device, dev) + struct sdw_driver { const char *name;
@@ -787,7 +800,8 @@ struct sdw_master_ops {
/** * struct sdw_bus - SoundWire bus - * @dev: Master linux device + * @dev: Shortcut to &bus->md->dev to avoid changing the entire code. + * @md: Master device * @link_id: Link id number, can be 0 to N, unique for each Master * @id: bus system-wide unique id * @slaves: list of Slaves on this bus @@ -813,6 +827,7 @@ struct sdw_master_ops { */ struct sdw_bus { struct device *dev; + struct sdw_master_device *md; unsigned int link_id; int id; struct list_head slaves;