[PATCH 7/7] soundwire: intel: introduce helper for link synchronization

From: Pierre-Louis Bossart
Date: Wed Mar 11 2020 - 18:11:01 EST


After arming the synchronization, the SYNCGO field controls the
hardware-based synchronization between links.

Move the programming and wait for clear of SYNCGO to dedicated helper.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
---
drivers/soundwire/intel.c | 47 ++++++++++++++++++++++++++++++++-------
1 file changed, 39 insertions(+), 8 deletions(-)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index 93d157d04eb9..e2dac2f0b343 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -524,6 +524,44 @@ static void intel_shim_sync_arm(struct sdw_intel *sdw)
mutex_unlock(sdw->link_res->shim_lock);
}

+static int intel_shim_sync_go_unlocked(struct sdw_intel *sdw)
+{
+ void __iomem *shim = sdw->link_res->shim;
+ u32 sync_reg;
+ int ret;
+
+ /* Read SYNC register */
+ sync_reg = intel_readl(shim, SDW_SHIM_SYNC);
+
+ /*
+ * Set SyncGO bit to synchronously trigger a bank switch for
+ * all the masters. A write to SYNCGO bit clears CMDSYNC bit for all
+ * the Masters.
+ */
+ sync_reg |= SDW_SHIM_SYNC_SYNCGO;
+
+ ret = intel_clear_bit(shim, SDW_SHIM_SYNC, sync_reg,
+ SDW_SHIM_SYNC_SYNCGO);
+
+ if (ret < 0)
+ dev_err(sdw->cdns.dev, "SyncGO clear failed: %d\n", ret);
+
+ return ret;
+}
+
+static int intel_shim_sync_go(struct sdw_intel *sdw)
+{
+ int ret;
+
+ mutex_lock(sdw->link_res->shim_lock);
+
+ ret = intel_shim_sync_go_unlocked(sdw);
+
+ mutex_unlock(sdw->link_res->shim_lock);
+
+ return ret;
+}
+
/*
* PDI routines
*/
@@ -775,15 +813,8 @@ static int intel_post_bank_switch(struct sdw_bus *bus)
ret = 0;
goto unlock;
}
- /*
- * Set SyncGO bit to synchronously trigger a bank switch for
- * all the masters. A write to SYNCGO bit clears CMDSYNC bit for all
- * the Masters.
- */
- sync_reg |= SDW_SHIM_SYNC_SYNCGO;

- ret = intel_clear_bit(shim, SDW_SHIM_SYNC, sync_reg,
- SDW_SHIM_SYNC_SYNCGO);
+ ret = intel_shim_sync_go_unlocked(sdw);
unlock:
mutex_unlock(sdw->link_res->shim_lock);

--
2.20.1