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authorPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>2019-05-22 14:47:31 -0500
committerVinod Koul <vkoul@kernel.org>2019-05-27 10:53:00 +0530
commit432732b801c82b139f8ca72e3b284fb999ac40d2 (patch)
tree5f3f8fdf396bb9fdfaeead11617a3f472fc71506 /drivers/soundwire
parent27f14331a7d434ff860b3d23c2379cf1fb814a3c (diff)
soundwire: intel_init: add checks on link numbers
Add mask to correctly read the SoundWire SHIM LCAP register. Only bits 2..0 are meaningful, the rest is about link synchronization and stream channel mapping. Without this mask, the hardware information would always be larger than whatever the BIOS would report. Also trap the case with zero links. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/soundwire')
-rw-r--r--drivers/soundwire/intel_init.c4
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/soundwire/intel_init.c b/drivers/soundwire/intel_init.c
index 771a53a5c033..70637a0383d2 100644
--- a/drivers/soundwire/intel_init.c
+++ b/drivers/soundwire/intel_init.c
@@ -81,6 +81,7 @@ static struct sdw_intel_ctx
/* Check SNDWLCAP.LCOUNT */
caps = ioread32(res->mmio_base + SDW_SHIM_BASE + SDW_SHIM_LCAP);
+ caps &= GENMASK(2, 0);
/* Check HW supported vs property value and use min of two */
count = min_t(u8, caps, count);
@@ -90,6 +91,9 @@ static struct sdw_intel_ctx
dev_err(&adev->dev, "Link count %d exceeds max %d\n",
count, SDW_MAX_LINKS);
return NULL;
+ } else if (!count) {
+ dev_warn(&adev->dev, "No SoundWire links detected\n");
+ return NULL;
}
dev_dbg(&adev->dev, "Creating %d SDW Link devices\n", count);