This patch adds support to parsing device tree based SoundWire slave devices.
Signed-off-by: Srinivas Kandagatla srinivas.kandagatla@linaro.org --- drivers/soundwire/bus.c | 2 ++ drivers/soundwire/bus.h | 1 + drivers/soundwire/slave.c | 52 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 55 insertions(+)
diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 49f64b2115b9..c2eaeb5c38ed 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -77,6 +77,8 @@ int sdw_add_bus_master(struct sdw_bus *bus) */ if (IS_ENABLED(CONFIG_ACPI) && ACPI_HANDLE(bus->dev)) ret = sdw_acpi_find_slaves(bus); + else if (IS_ENABLED(CONFIG_OF) && bus->dev->of_node) + ret = sdw_of_find_slaves(bus); else ret = -ENOTSUPP; /* No ACPI/DT so error out */
diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h index 3048ca153f22..ee46befedbd1 100644 --- a/drivers/soundwire/bus.h +++ b/drivers/soundwire/bus.h @@ -15,6 +15,7 @@ static inline int sdw_acpi_find_slaves(struct sdw_bus *bus) } #endif
+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);
diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c index f39a5815e25d..3ef265d2ee89 100644 --- a/drivers/soundwire/slave.c +++ b/drivers/soundwire/slave.c @@ -2,6 +2,7 @@ // Copyright(c) 2015-17 Intel Corporation.
#include <linux/acpi.h> +#include <linux/of.h> #include <linux/soundwire/sdw.h> #include <linux/soundwire/sdw_type.h> #include "bus.h" @@ -35,6 +36,7 @@ static int sdw_slave_add(struct sdw_bus *bus,
slave->dev.release = sdw_slave_release; slave->dev.bus = &sdw_bus_type; + slave->dev.of_node = of_node_get(to_of_node(fwnode)); slave->bus = bus; slave->status = SDW_SLAVE_UNATTACHED; slave->dev_num = 0; @@ -112,3 +114,53 @@ int sdw_acpi_find_slaves(struct sdw_bus *bus) }
#endif + +/* + * sdw_of_find_slaves() - Find Slave devices in master device tree node + * @bus: SDW bus instance + * + * Scans Master DT node for SDW child Slave devices and registers it. + */ +int sdw_of_find_slaves(struct sdw_bus *bus) +{ + struct device *dev = bus->dev; + struct device_node *node; + + for_each_child_of_node(bus->dev->of_node, node) { + int link_id, sdw_version, ret, len; + const char *compat = NULL; + struct sdw_slave_id id; + const __be32 *addr; + + compat = of_get_property(node, "compatible", NULL); + if (!compat) + continue; + + ret = sscanf(compat, "sdw%01x%04hx%04hx%02hhx", &sdw_version, + &id.mfg_id, &id.part_id, &id.class_id); + + if (ret != 4) { + dev_err(dev, "Invalid compatible string found %s\n", + compat); + continue; + } + + addr = of_get_property(node, "reg", &len); + if (!addr || (len < 2 * sizeof(u32))) { + dev_err(dev, "Invalid Instance and Link ID\n"); + continue; + } + + id.unique_id = be32_to_cpup(addr++); + link_id = be32_to_cpup(addr); + id.sdw_version = sdw_version; + + /* Check for link_id match */ + if (link_id != bus->link_id) + continue; + + sdw_slave_add(bus, &id, of_fwnode_handle(node)); + } + + return 0; +}