soundwire: core: add device tree support for slave devices

This patch adds support to parsing device tree based
SoundWire slave devices.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20190829163514.11221-3-srinivas.kandagatla@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
This commit is contained in:
Srinivas Kandagatla 2019-08-29 17:35:12 +01:00 committed by Vinod Koul
parent dd4689e2b6
commit a2e484585a
3 changed files with 55 additions and 0 deletions

View File

@ -79,6 +79,8 @@ 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 */

View File

@ -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);

View File

@ -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;
@ -113,3 +115,53 @@ 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 Link and Instance ID\n");
continue;
}
link_id = be32_to_cpup(addr++);
id.unique_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;
}