[PATCH 08/11] soundwire: stream: enable hw_sync as needed by hardware

[Bard Liao]

From: Pierre-Louis Bossart <pierre-louis.boss...@linux.intel.com>

Use platform-specific information to decide when to use hw_sync, not
only a number of links > 1.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.boss...@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.l...@linux.intel.com>
---
 drivers/soundwire/stream.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c
index 37290a799023..e4cf484f5905 100644
--- a/drivers/soundwire/stream.c
+++ b/drivers/soundwire/stream.c
@@ -689,9 +689,9 @@ static int sdw_bank_switch(struct sdw_bus *bus, int 
m_rt_count)
 
        /*
         * Set the multi_link flag only when both the hardware supports
-        * and there is a stream handled by multiple masters
+        * and hardware-based sync is required
         */
-       multi_link = bus->multi_link && (m_rt_count > 1);
+       multi_link = bus->multi_link && (m_rt_count >= bus->hw_sync_min_links);
 
        if (multi_link)
                ret = sdw_transfer_defer(bus, wr_msg, &bus->defer_msg);
@@ -760,13 +760,16 @@ static int do_bank_switch(struct sdw_stream_runtime 
*stream)
        const struct sdw_master_ops *ops;
        struct sdw_bus *bus;
        bool multi_link = false;
+       int m_rt_count;
        int ret = 0;
 
+       m_rt_count = stream->m_rt_count;
+
        list_for_each_entry(m_rt, &stream->master_list, stream_node) {
                bus = m_rt->bus;
                ops = bus->ops;
 
-               if (bus->multi_link) {
+               if (bus->multi_link && m_rt_count >= bus->hw_sync_min_links) {
                        multi_link = true;
                        mutex_lock(&bus->msg_lock);
                }
@@ -787,7 +790,7 @@ static int do_bank_switch(struct sdw_stream_runtime *stream)
                 * synchronized across all Masters and happens later as a
                 * part of post_bank_switch ops.
                 */
-               ret = sdw_bank_switch(bus, stream->m_rt_count);
+               ret = sdw_bank_switch(bus, m_rt_count);
                if (ret < 0) {
                        dev_err(bus->dev, "Bank switch failed: %d\n", ret);
                        goto error;
@@ -813,7 +816,7 @@ static int do_bank_switch(struct sdw_stream_runtime *stream)
                                        ret);
                                goto error;
                        }
-               } else if (bus->multi_link && stream->m_rt_count > 1) {
+               } else if (multi_link) {
                        dev_err(bus->dev,
                                "Post bank switch ops not implemented\n");
                        goto error;
@@ -831,7 +834,7 @@ static int do_bank_switch(struct sdw_stream_runtime *stream)
                        goto error;
                }
 
-               if (bus->multi_link)
+               if (multi_link)
                        mutex_unlock(&bus->msg_lock);
        }
 
-- 
2.17.1