On Thu, Jul 25, 2019 at 06:40:01PM -0500, Pierre-Louis Bossart wrote:
Per the hardware documentation, all changes to MCP_CONFIG, MCP_CONTROL, MCP_CMDCTRL and MCP_PHYCTRL need to be validated with a self-clearing write to MCP_CONFIG_UPDATE.
For some reason, the existing code only does this write to CONFIG_UPDATE when enabling interrupts. Add a helper and do the update when the CONFIG is changed.
the sequence of intel_probe is as follows: 1. intel_link_power_up 2. intel_shim_init 3. sdw_cdns_init 4. sdw_cdns_enable_interrupt
Since we do self-clearing write to MCP_CONFIG_UPDATE in sdw_cdns_enable_interrupt once for all the config changes, we dont perform it as part of sdw_cdns_init.
It does make sense to seperate it out from sdw_cdns_enable_interrupt so that we can use when clockstop is enabled where we dont need to enable interrupts.
Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
drivers/soundwire/cadence_master.c | 29 +++++++++++++++++++++-------- 1 file changed, 21 insertions(+), 8 deletions(-)
diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index 9f611a1fff0a..eb46cf651d62 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -224,6 +224,22 @@ static int cdns_clear_bit(struct sdw_cdns *cdns, int offset, u32 value) return -EAGAIN; }
+/*
- all changes to the MCP_CONFIG, MCP_CONTROL, MCP_CMDCTRL and MCP_PHYCTRL
- need to be confirmed with a write to MCP_CONFIG_UPDATE
- */
+static int cdns_update_config(struct sdw_cdns *cdns) +{
- int ret;
- ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE,
CDNS_MCP_CONFIG_UPDATE_BIT);- if (ret < 0)
dev_err(cdns->dev, "Config update timedout\n");- return ret;
+}
/*
- debugfs
*/ @@ -758,15 +774,9 @@ static int _cdns_enable_interrupt(struct sdw_cdns *cdns) */ int sdw_cdns_enable_interrupt(struct sdw_cdns *cdns) {
int ret;
_cdns_enable_interrupt(cdns);
ret = cdns_clear_bit(cdns, CDNS_MCP_CONFIG_UPDATE,
CDNS_MCP_CONFIG_UPDATE_BIT);if (ret < 0)
dev_err(cdns->dev, "Config update timedout\n");return ret;
- return 0;
} EXPORT_SYMBOL(sdw_cdns_enable_interrupt);
@@ -943,7 +953,10 @@ int sdw_cdns_init(struct sdw_cdns *cdns)
cdns_writel(cdns, CDNS_MCP_CONFIG, val);
- return 0;
- /* commit changes */
- ret = cdns_update_config(cdns);
- return ret;
} EXPORT_SYMBOL(sdw_cdns_init);
-- 2.20.1
--