In cases of multiple master in a stream, synchronization between multiple master(s) is achieved by performing bank switch together and using master methods.
Add sdw_ml_bank_switch() to wait for completion of bank switch.
Signed-off-by: Sanyog Kale sanyog.r.kale@intel.com Signed-off-by: Vinod Koul vkoul@kernel.org Signed-off-by: Shreyas NC shreyas.nc@intel.com --- drivers/soundwire/bus.h | 2 + drivers/soundwire/stream.c | 102 ++++++++++++++++++++++++++++++++++++++---- include/linux/soundwire/sdw.h | 2 + 3 files changed, 97 insertions(+), 9 deletions(-)
diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h index b6cfbdf..c77de05 100644 --- a/drivers/soundwire/bus.h +++ b/drivers/soundwire/bus.h @@ -4,6 +4,8 @@ #ifndef __SDW_BUS_H #define __SDW_BUS_H
+#define DEFAULT_BANK_SWITCH_TIMEOUT 3000 + #if IS_ENABLED(CONFIG_ACPI) int sdw_acpi_find_slaves(struct sdw_bus *bus); #else diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c index 36506a7..103840c 100644 --- a/drivers/soundwire/stream.c +++ b/drivers/soundwire/stream.c @@ -638,6 +638,8 @@ static int sdw_bank_switch(struct sdw_bus *bus) if (!wr_msg) return -ENOMEM;
+ bus->defer_msg.msg = wr_msg; + wbuf = kzalloc(sizeof(*wbuf), GFP_KERNEL); if (!wbuf) { ret = -ENOMEM; @@ -658,17 +660,23 @@ static int sdw_bank_switch(struct sdw_bus *bus) SDW_MSG_FLAG_WRITE, wbuf); wr_msg->ssp_sync = true;
- ret = sdw_transfer(bus, wr_msg); + if (bus->multi_link) + ret = sdw_transfer_defer(bus, wr_msg, &bus->defer_msg); + else + ret = sdw_transfer(bus, wr_msg); + if (ret < 0) { dev_err(bus->dev, "Slave frame_ctrl reg write failed"); goto error; }
- kfree(wr_msg); - kfree(wbuf); - bus->defer_msg.msg = NULL; - bus->params.curr_bank = !bus->params.curr_bank; - bus->params.next_bank = !bus->params.next_bank; + if (!bus->multi_link) { + kfree(wr_msg); + kfree(wbuf); + bus->defer_msg.msg = NULL; + bus->params.curr_bank = !bus->params.curr_bank; + bus->params.next_bank = !bus->params.next_bank; + }
return 0;
@@ -679,25 +687,65 @@ static int sdw_bank_switch(struct sdw_bus *bus) return ret; }
+/** + * sdw_ml_sync_bank_switch: Multilink register bank switch + * + * @bus: SDW bus instance + * + * Caller function should free the buffers on error + */ +static int sdw_ml_sync_bank_switch(struct sdw_bus *bus) +{ + unsigned long time_left; + int ret = 0; + + if (!bus->multi_link) + return ret; + + /* Wait for completion of transfer */ + time_left = wait_for_completion_timeout(&bus->defer_msg.complete, + bus->bank_switch_timeout); + + if (!time_left) { + dev_err(bus->dev, "Controller Timed out on bank switch"); + return -ETIMEDOUT; + } + + bus->params.curr_bank = !bus->params.curr_bank; + bus->params.next_bank = !bus->params.next_bank; + + if (bus->defer_msg.msg) { + kfree(bus->defer_msg.msg->buf); + kfree(bus->defer_msg.msg); + } + + return ret; +} + static int do_bank_switch(struct sdw_stream_runtime *stream) { struct sdw_master_runtime *m_rt = NULL; const struct sdw_master_ops *ops; struct sdw_bus *bus = NULL; + bool multi_link = false; int ret = 0;
- list_for_each_entry(m_rt, &stream->master_list, stream_node) { bus = m_rt->bus; ops = bus->ops;
+ if (bus->multi_link) { + multi_link = true; + mutex_lock(&bus->msg_lock); + } + /* Pre-bank switch */ if (ops->pre_bank_switch) { ret = ops->pre_bank_switch(bus); if (ret < 0) { dev_err(bus->dev, "Pre bank switch op failed: %d", ret); - return ret; + goto msg_unlock; } }
@@ -705,7 +753,8 @@ static int do_bank_switch(struct sdw_stream_runtime *stream) ret = sdw_bank_switch(bus); if (ret < 0) { dev_err(bus->dev, "Bank switch failed: %d", ret); - return ret; + goto error; + } }
@@ -718,8 +767,43 @@ static int do_bank_switch(struct sdw_stream_runtime *stream) if (ret < 0) { dev_err(bus->dev, "Post bank switch op failed: %d", ret); + goto error; } } + + /* Set the bank switch timeout to default, if not set */ + if (!bus->bank_switch_timeout) + bus->bank_switch_timeout = DEFAULT_BANK_SWITCH_TIMEOUT; + + ret = sdw_ml_sync_bank_switch(bus); + if (ret < 0) { + dev_err(bus->dev, + "Post bank switch op failed: %d", ret); + goto error; + } + + mutex_unlock(&bus->msg_lock); + } + + return ret; + +error: + list_for_each_entry(m_rt, &stream->master_list, stream_node) { + + bus = m_rt->bus; + + kfree(bus->defer_msg.msg->buf); + kfree(bus->defer_msg.msg); + } + +msg_unlock: + + if (multi_link) { + list_for_each_entry(m_rt, &stream->master_list, stream_node) { + bus = m_rt->bus; + if (mutex_is_locked(&bus->msg_lock)) + mutex_unlock(&bus->msg_lock); + } }
return ret; diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index 03df709..f006029 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -673,6 +673,7 @@ struct sdw_master_ops { * @params: Current bus parameters * @prop: Master properties * @m_rt_list: List of Master instance of all stream(s) running on Bus. This + * @multi_link: if multi links are supported * is used to compute and program bus bandwidth, clock, frame shape, * transport and port parameters * @defer_msg: Defer message @@ -691,6 +692,7 @@ struct sdw_bus { struct sdw_bus_params params; struct sdw_master_prop prop; struct list_head m_rt_list; + bool multi_link; struct sdw_defer defer_msg; unsigned int clk_stop_timeout; u32 bank_switch_timeout;