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>
/* 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);
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);