[PATCH 11/17] soundwire: intel: read mclk_freq property from firmware

From: Pierre-Louis Bossart
Date: Mon Aug 05 2019 - 20:56:16 EST


The BIOS provides an Intel-specific property, let's use it to avoid
hard-coded clock dividers.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
---
drivers/soundwire/intel.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index fe3266bc1d12..3f876642cb7f 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -909,11 +909,37 @@ static int intel_register_dai(struct sdw_intel *sdw)
dais, num_dai);
}

+static int sdw_master_read_intel_prop(struct sdw_bus *bus)
+{
+ struct sdw_master_prop *prop = &bus->prop;
+ struct fwnode_handle *link;
+ char name[32];
+ int nval, i;
+
+ /* Find master handle */
+ snprintf(name, sizeof(name),
+ "mipi-sdw-link-%d-subproperties", bus->link_id);
+
+ link = device_get_named_child_node(bus->dev, name);
+ if (!link) {
+ dev_err(bus->dev, "Master node %s not found\n", name);
+ return -EIO;
+ }
+
+ fwnode_property_read_u32(link,
+ "intel-sdw-ip-clock",
+ &prop->mclk_freq);
+ return 0;
+}
+
static int intel_prop_read(struct sdw_bus *bus)
{
/* Initialize with default handler to read all DisCo properties */
sdw_master_read_prop(bus);

+ /* read Intel-specific properties */
+ sdw_master_read_intel_prop(bus);
+
return 0;
}

--
2.20.1