Soundwire: intel_init: save Slave(s) _ADR info in sdw_intel_ctx

Save ACPI information in context so that we can match machine driver
with sdw _ADR matching tables.

Suggested-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200716150947.22119-10-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/intel_init.c

@@ -188,7 +188,11 @@ static struct sdw_intel_ctx
 	struct sdw_intel_link_res *link;
 	struct sdw_intel_ctx *ctx;
 	struct acpi_device *adev;
+	struct sdw_slave *slave;
+	struct list_head *node;
+	struct sdw_bus *bus;
 	u32 link_mask;
+	int num_slaves = 0;
 	int count;
 	int i;
 
@@ -265,6 +269,26 @@ static struct sdw_intel_ctx
 		link->cdns = platform_get_drvdata(pdev);
 
 		list_add_tail(&link->list, &ctx->link_list);
+		bus = &link->cdns->bus;
+		/* Calculate number of slaves */
+		list_for_each(node, &bus->slaves)
+			num_slaves++;
+	}
+
+	ctx->ids = devm_kcalloc(&adev->dev, num_slaves,
+				sizeof(*ctx->ids), GFP_KERNEL);
+	if (!ctx->ids)
+		goto err;
+
+	ctx->num_slaves = num_slaves;
+	i = 0;
+	list_for_each_entry(link, &ctx->link_list, list) {
+		bus = &link->cdns->bus;
+		list_for_each_entry(slave, &bus->slaves, node) {
+			ctx->ids[i].id = slave->id;
+			ctx->ids[i].link_id = bus->link_id;
+			i++;
+		}
 	}
 
 	return ctx;