Since we want an explicit support for the SoundWire Master device, add the definitions, following the Greybus example of a 'Host Device'.
A parent (such as the Intel audio controller) would use sdw_md_add() to create the device, passing a driver as a parameter. The sdw_md_release() would be called when put_device() is invoked by the parent. We use the shortcut 'md' for 'master device' to avoid very long function names.
The 'Master Device' driver exposes interfaces for probe/startup/shutdown/remove and a placeholder for autonomous clock stop support (when the bus control is handed over to a lower-power solution, typically in D0ix modes).
Module namespace support is added in a separate patch.
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com --- drivers/soundwire/Makefile | 2 +- drivers/soundwire/bus_type.c | 5 ++- drivers/soundwire/master.c | 63 ++++++++++++++++++++++++++++++ include/linux/soundwire/sdw.h | 38 ++++++++++++++++++ include/linux/soundwire/sdw_type.h | 9 +++++ 5 files changed, 115 insertions(+), 2 deletions(-) create mode 100644 drivers/soundwire/master.c
diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile index 563894e5ecaf..89b29819dd3a 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_type.c b/drivers/soundwire/bus_type.c index 605bc7ae57a8..2e4e8c2e629f 100644 --- a/drivers/soundwire/bus_type.c +++ b/drivers/soundwire/bus_type.c @@ -66,7 +66,10 @@ int sdw_uevent(struct device *dev, struct kobj_uevent_env *env) * callback is set to use this function for a * different device type (e.g. Master or Monitor) */ - dev_err(dev, "uevent for unknown Soundwire type\n"); + if (is_sdw_master_device(dev)) + dev_err(dev, "uevent for SoundWire Master type\n"); + else + dev_err(dev, "uevent for unknown Soundwire type\n"); return -EINVAL; }
diff --git a/drivers/soundwire/master.c b/drivers/soundwire/master.c new file mode 100644 index 000000000000..b018c561708e --- /dev/null +++ b/drivers/soundwire/master.c @@ -0,0 +1,63 @@ +// SPDX-License-Identifier: (GPL-2.0) +// Copyright(c) 2019 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_md_release(struct device *dev) +{ + struct sdw_master_device *md = to_sdw_master_device(dev); + + kfree(md); +} + +struct device_type sdw_md_type = { + .name = "soundwire_master", + .release = sdw_md_release, +}; + +struct sdw_master_device *sdw_md_add(struct sdw_md_driver *driver, + struct device *parent, + struct fwnode_handle *fwnode, + int link_id) +{ + struct sdw_master_device *md; + int ret; + + if (!driver->probe) { + dev_err(parent, "mandatory probe callback missing\n"); + return ERR_PTR(-EINVAL); + } + + md = kzalloc(sizeof(*md), GFP_KERNEL); + if (!md) + return ERR_PTR(-ENOMEM); + + md->link_id = link_id; + + md->driver = driver; + + md->dev.parent = parent; + md->dev.fwnode = fwnode; + md->dev.bus = &sdw_bus_type; + md->dev.type = &sdw_md_type; + md->dev.dma_mask = md->dev.parent->dma_mask; + dev_set_name(&md->dev, "sdw-master-%d", md->link_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); + return ERR_PTR(-ENOMEM); + } + + return md; +} +EXPORT_SYMBOL_GPL(sdw_md_add); diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index 5b1180f1e6b5..f73c355de5e5 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -585,6 +585,16 @@ struct sdw_slave { #define to_sdw_slave_device(d) \ container_of(d, struct sdw_slave, dev)
+struct sdw_master_device { + struct device dev; + int link_id; + struct sdw_md_driver *driver; + void *pdata; +}; + +#define to_sdw_master_device(d) \ + container_of(d, struct sdw_master_device, dev) + struct sdw_driver { const char *name;
@@ -599,6 +609,29 @@ struct sdw_driver { struct device_driver driver; };
+/** + * struct sdw_md_driver - SoundWire 'Master Device' driver + * + * @probe: initializations and allocation (hardware may not be enabled yet) + * @startup: initialization handled after the hardware is enabled, all + * clock/power dependencies are available + * @shutdown: cleanups before hardware is disabled (optional) + * @free: free all remaining resources + * @autonomous_clock_stop_enable: enable/disable driver control while + * in clock-stop mode, typically in always-on/D0ix modes. When the driver + * yields control, another entity in the system (typically firmware + * running on an always-on microprocessor) is responsible to tracking + * Slave-initiated wakes + */ +struct sdw_md_driver { + int (*probe)(struct sdw_master_device *md, void *link_ctx); + int (*startup)(struct sdw_master_device *md); + int (*shutdown)(struct sdw_master_device *md); + int (*remove)(struct sdw_master_device *md); + int (*autonomous_clock_stop_enable)(struct sdw_master_device *md, + bool state); +}; + #define SDW_SLAVE_ENTRY(_mfg_id, _part_id, _drv_data) \ { .mfg_id = (_mfg_id), .part_id = (_part_id), \ .driver_data = (unsigned long)(_drv_data) } @@ -788,6 +821,11 @@ struct sdw_bus { int sdw_add_bus_master(struct sdw_bus *bus); void sdw_delete_bus_master(struct sdw_bus *bus);
+struct sdw_master_device *sdw_md_add(struct sdw_md_driver *driver, + struct device *parent, + struct fwnode_handle *fwnode, + int link_id); + /** * sdw_port_config: Master or Slave Port configuration * diff --git a/include/linux/soundwire/sdw_type.h b/include/linux/soundwire/sdw_type.h index c681b3426478..a2a5ea7843a6 100644 --- a/include/linux/soundwire/sdw_type.h +++ b/include/linux/soundwire/sdw_type.h @@ -6,15 +6,24 @@
extern struct bus_type sdw_bus_type; extern struct device_type sdw_slave_type; +extern struct device_type sdw_md_type;
static inline int is_sdw_slave(const struct device *dev) { return dev->type == &sdw_slave_type; }
+static inline int is_sdw_master_device(const struct device *dev) +{ + return dev->type == &sdw_md_type; +} + #define to_sdw_slave_driver(_drv) \ container_of(_drv, struct sdw_driver, driver)
+#define to_sdw_md_driver(_drv) \ + container_of(_drv, struct sdw_md_driver, driver) + #define sdw_register_slave_driver(drv) \ __sdw_register_slave_driver(drv, THIS_MODULE)