Re: [PATCH v2 1/5] soundwire: Add compute_params callback

From: Pierre-Louis Bossart
Date: Tue Aug 13 2019 - 10:53:11 EST


On 8/13/19 3:35 AM, Srinivas Kandagatla wrote:
From: Vinod Koul <vkoul@xxxxxxxxxx>

This callback allows masters to compute the bus parameters required.

This looks like a partial use of the patch ('soundwire: Add Intel resource management algorithm')? see comments below


Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
drivers/soundwire/stream.c | 10 ++++++++++
include/linux/soundwire/sdw.h | 2 ++
2 files changed, 12 insertions(+)

diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c
index a0476755a459..60bc2fe42928 100644
--- a/drivers/soundwire/stream.c
+++ b/drivers/soundwire/stream.c
@@ -1483,6 +1483,16 @@ static int _sdw_prepare_stream(struct sdw_stream_runtime *stream)
bus->params.bandwidth += m_rt->stream->params.rate *
m_rt->ch_count * m_rt->stream->params.bps;
+ /* Compute params */
+ if (bus->compute_params) {
+ ret = bus->compute_params(bus);
+ if (ret < 0) {
+ dev_err(bus->dev, "Compute params failed: %d",
+ ret);
+ return ret;
+ }
+ }
+

This would need to be duplicated for deprepare (as was done in the Intel patch).

/* Program params */
ret = sdw_program_params(bus);
if (ret < 0) {
diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h
index bea46bd8b6ce..aac68e879fae 100644
--- a/include/linux/soundwire/sdw.h
+++ b/include/linux/soundwire/sdw.h
@@ -718,6 +718,7 @@ struct sdw_master_ops {
* Bit set implies used number, bit clear implies unused number.
* @bus_lock: bus lock
* @msg_lock: message lock
+ * @compute_params: points to Bus resource management implementation
* @ops: Master callback ops
* @port_ops: Master port callback ops
* @params: Current bus parameters
@@ -739,6 +740,7 @@ struct sdw_bus {
DECLARE_BITMAP(assigned, SDW_MAX_DEVICES);
struct mutex bus_lock;
struct mutex msg_lock;
+ int (*compute_params)(struct sdw_bus *bus);

not sure I understand how it's set? We have a default in the Intel patch.

const struct sdw_master_ops *ops;
const struct sdw_master_port_ops *port_ops;
struct sdw_bus_params params;