soundwire: Add SoundWire bus type

This adds the base SoundWire bus type, bus and driver registration.
along with changes to module device table for new SoundWire
device type.

Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-By: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

3 files changed, 133 insertions, 0 deletions

diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h
index 48e188327c02..48fb2b43c35a 100644
--- a/include/linux/mod_devicetable.h
+++ b/include/linux/mod_devicetable.h
@@ -229,6 +229,12 @@ struct hda_device_id {
 	unsigned long driver_data;
 };
 
+struct sdw_device_id {
+	__u16 mfg_id;
+	__u16 part_id;
+	kernel_ulong_t driver_data;
+};
+
 /*
  * Struct used for matching a device
  */
diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h
new file mode 100644
index 000000000000..869d7041d9fc
--- /dev/null
+++ b/include/linux/soundwire/sdw.h
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2015-17 Intel Corporation.
+
+#ifndef __SOUNDWIRE_H
+#define __SOUNDWIRE_H
+
+struct sdw_bus;
+struct sdw_slave;
+
+#define SDW_MAX_DEVICES			11
+
+/**
+ * enum sdw_slave_status - Slave status
+ * @SDW_SLAVE_UNATTACHED: Slave is not attached with the bus.
+ * @SDW_SLAVE_ATTACHED: Slave is attached with bus.
+ * @SDW_SLAVE_ALERT: Some alert condition on the Slave
+ * @SDW_SLAVE_RESERVED: Reserved for future use
+ */
+enum sdw_slave_status {
+	SDW_SLAVE_UNATTACHED = 0,
+	SDW_SLAVE_ATTACHED = 1,
+	SDW_SLAVE_ALERT = 2,
+	SDW_SLAVE_RESERVED = 3,
+};
+
+/*
+ * SDW Slave Structures and APIs
+ */
+
+/**
+ * struct sdw_slave_id - Slave ID
+ * @mfg_id: MIPI Manufacturer ID
+ * @part_id: Device Part ID
+ * @class_id: MIPI Class ID, unused now.
+ * Currently a placeholder in MIPI SoundWire Spec
+ * @unique_id: Device unique ID
+ * @sdw_version: SDW version implemented
+ *
+ * The order of the IDs here does not follow the DisCo spec definitions
+ */
+struct sdw_slave_id {
+	__u16 mfg_id;
+	__u16 part_id;
+	__u8 class_id;
+	__u8 unique_id:4;
+	__u8 sdw_version:4;
+};
+
+/**
+ * struct sdw_slave - SoundWire Slave
+ * @id: MIPI device ID
+ * @dev: Linux device
+ * @status: Status reported by the Slave
+ * @bus: Bus handle
+ * @node: node for bus list
+ * @dev_num: Device Number assigned by Bus
+ */
+struct sdw_slave {
+	struct sdw_slave_id id;
+	struct device dev;
+	enum sdw_slave_status status;
+	struct sdw_bus *bus;
+	struct list_head node;
+	u16 dev_num;
+};
+
+#define dev_to_sdw_dev(_dev) container_of(_dev, struct sdw_slave, dev)
+
+struct sdw_driver {
+	const char *name;
+
+	int (*probe)(struct sdw_slave *sdw,
+			const struct sdw_device_id *id);
+	int (*remove)(struct sdw_slave *sdw);
+	void (*shutdown)(struct sdw_slave *sdw);
+
+	const struct sdw_device_id *id_table;
+	const struct sdw_slave_ops *ops;
+
+	struct device_driver driver;
+};
+
+#define SDW_SLAVE_ENTRY(_mfg_id, _part_id, _drv_data) \
+	{ .mfg_id = (_mfg_id), .part_id = (_part_id), \
+	  .driver_data = (unsigned long)(_drv_data) }
+
+/*
+ * SDW master structures and APIs
+ */
+
+/**
+ * struct sdw_bus - SoundWire bus
+ * @dev: Master linux device
+ * @link_id: Link id number, can be 0 to N, unique for each Master
+ * @slaves: list of Slaves on this bus
+ * @assigned: Bitmap for Slave device numbers.
+ * Bit set implies used number, bit clear implies unused number.
+ * @bus_lock: bus lock
+ */
+struct sdw_bus {
+	struct device *dev;
+	unsigned int link_id;
+	struct list_head slaves;
+	DECLARE_BITMAP(assigned, SDW_MAX_DEVICES);
+	struct mutex bus_lock;
+};
+
+#endif /* __SOUNDWIRE_H */
diff --git a/include/linux/soundwire/sdw_type.h b/include/linux/soundwire/sdw_type.h
new file mode 100644
index 000000000000..9fd553e553e9
--- /dev/null
+++ b/include/linux/soundwire/sdw_type.h
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright(c) 2015-17 Intel Corporation.
+
+#ifndef __SOUNDWIRE_TYPES_H
+#define __SOUNDWIRE_TYPES_H
+
+extern struct bus_type sdw_bus_type;
+
+#define drv_to_sdw_driver(_drv) container_of(_drv, struct sdw_driver, driver)
+
+#define sdw_register_driver(drv) \
+	__sdw_register_driver(drv, THIS_MODULE)
+
+int __sdw_register_driver(struct sdw_driver *drv, struct module *);
+void sdw_unregister_driver(struct sdw_driver *drv);
+
+int sdw_slave_modalias(const struct sdw_slave *slave, char *buf, size_t size);
+
+#endif /* __SOUNDWIRE_TYPES_H */