[RFC PATCH 1/2] soundwire: add support for static port mapping

From: Srinivas Kandagatla
Date: Wed Jan 20 2021 - 13:04:56 EST


Some of the soundwire controllers can have static functions assigned
to each port, like some ports can only do PCM or PDM. This is the situation
with some of the Qualcomm Controllers.

In such cases its not correct to assign/map any free port on master
during streaming.

So, this patch provides a way to pass mapped port number along
with the port config, so that master can assign correct ports based
on the provided static mapping.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
drivers/soundwire/bus.h | 4 ++++
drivers/soundwire/stream.c | 4 ++++
include/linux/soundwire/sdw.h | 4 ++++
3 files changed, 12 insertions(+)

diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h
index 2e049d39c6e5..e812557c3293 100644
--- a/drivers/soundwire/bus.h
+++ b/drivers/soundwire/bus.h
@@ -85,6 +85,8 @@ int sdw_find_col_index(int col);
* @num: Port number. For audio streams, valid port number ranges from
* [1,14]
* @ch_mask: Channel mask
+ * @mapped_port_num: Port number to map on Master or Slave in Static Configuration
+ * @is_static_map: true for static port mapping
* @transport_params: Transport parameters
* @port_params: Port parameters
* @port_node: List node for Master or Slave port_list
@@ -95,6 +97,8 @@ int sdw_find_col_index(int col);
struct sdw_port_runtime {
int num;
int ch_mask;
+ unsigned int mapped_port_num;
+ bool is_static_map;
struct sdw_transport_params transport_params;
struct sdw_port_params port_params;
struct list_head port_node;
diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c
index 1099b5d1262b..eab3bc0c95ed 100644
--- a/drivers/soundwire/stream.c
+++ b/drivers/soundwire/stream.c
@@ -1202,6 +1202,10 @@ static struct sdw_port_runtime

p_rt->ch_mask = port_config[port_index].ch_mask;
p_rt->num = port_config[port_index].num;
+ p_rt->is_static_map = port_config[port_index].is_static_map;
+
+ if (p_rt->is_static_map)
+ p_rt->mapped_port_num = port_config[port_index].mapped_port_num;

return p_rt;
}
diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h
index f0b01b728640..a523f062993d 100644
--- a/include/linux/soundwire/sdw.h
+++ b/include/linux/soundwire/sdw.h
@@ -894,10 +894,14 @@ void sdw_bus_master_delete(struct sdw_bus *bus);
*
* @num: Port number
* @ch_mask: channels mask for port
+ * @mapped_port_num: Port number to map on Master or Slave in Static Configuration
+ * @is_static_map: true for static port mapping
*/
struct sdw_port_config {
unsigned int num;
unsigned int ch_mask;
+ unsigned int mapped_port_num;
+ bool is_static_map;
};

/**
--
2.21.0