[PATCH AUTOSEL 4.19 10/33] soundwire: intel: fix channel number reported by hardware

Sasha Levin
2019-09-29T17:40:18Z

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

[ Upstream commit 18046335643de6d21327f5ae034c8fb8463f6715 ]

On all released Intel controllers (CNL/CML/ICL), PDI2 reports an
invalid count, force the correct hardware-supported value

This may have to be revisited with platform-specific values if the
hardware changes, but for now this is good enough.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20190806005522.22642-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/soundwire/intel.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
index a6e2581ada703..29bc99c4a7b66 100644
--- a/drivers/soundwire/intel.c
+++ b/drivers/soundwire/intel.c
@@ -282,6 +282,16 @@ intel_pdi_get_ch_cap(struct sdw_intel *sdw, unsigned int pdi_num, bool pcm)

if (pcm) {
count = intel_readw(shim, SDW_SHIM_PCMSYCHC(link_id, pdi_num));
+
+ /*
+ * WORKAROUND: on all existing Intel controllers, pdi
+ * number 2 reports channel count as 1 even though it
+ * supports 8 channels. Performing hardcoding for pdi
+ * number 2.
+ */
+ if (pdi_num == 2)
+ count = 7;
+
} else {
count = intel_readw(shim, SDW_SHIM_PDMSCAP(link_id));
count = ((count & SDW_SHIM_PDMSCAP_CPSS) >>
--
2.20.1