[PATCH 3/3] soundwire: add helper macros for devID fields

[Pierre-Louis Bossart]

Move bit extractors to macros, so that the definitions can be used by
other drivers parsing the MIPI definitions extracted from firmware
tables (ACPI or DT).

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
---
 drivers/soundwire/bus.c       | 21 +++++----------------
 include/linux/soundwire/sdw.h | 23 +++++++++++++++++++++++
 2 files changed, 28 insertions(+), 16 deletions(-)

diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c
index b8a7a84aca1c..01be7220d117 100644
--- a/drivers/soundwire/bus.c
+++ b/drivers/soundwire/bus.c
@@ -589,22 +589,11 @@ void sdw_extract_slave_id(struct sdw_bus *bus,
 {
 	dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
 
-	/*
-	 * Spec definition
-	 *   Register		Bit	Contents
-	 *   DevId_0 [7:4]	47:44	sdw_version
-	 *   DevId_0 [3:0]	43:40	unique_id
-	 *   DevId_1		39:32	mfg_id [15:8]
-	 *   DevId_2		31:24	mfg_id [7:0]
-	 *   DevId_3		23:16	part_id [15:8]
-	 *   DevId_4		15:08	part_id [7:0]
-	 *   DevId_5		07:00	class_id
-	 */
-	id->sdw_version = (addr >> 44) & GENMASK(3, 0);
-	id->unique_id = (addr >> 40) & GENMASK(3, 0);
-	id->mfg_id = (addr >> 24) & GENMASK(15, 0);
-	id->part_id = (addr >> 8) & GENMASK(15, 0);
-	id->class_id = addr & GENMASK(7, 0);
+	id->sdw_version = SDW_VERSION(addr);
+	id->unique_id = SDW_UNIQUE_ID(addr);
+	id->mfg_id = SDW_MFG_ID(addr);
+	id->part_id = SDW_PART_ID(addr);
+	id->class_id = SDW_CLASS_ID(addr);
 
 	dev_dbg(bus->dev,
 		"SDW Slave class_id %x, part_id %x, mfg_id %x, unique_id %x, version %x\n",
diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h
index b8427df034ce..ee349a4c5349 100644
--- a/include/linux/soundwire/sdw.h
+++ b/include/linux/soundwire/sdw.h
@@ -439,6 +439,29 @@ struct sdw_slave_id {
 	__u8 sdw_version:4;
 };
 
+/*
+ * Helper macros to extract the MIPI-defined IDs
+ *
+ * Spec definition
+ *   Register		Bit	Contents
+ *   DevId_0 [7:4]	47:44	sdw_version
+ *   DevId_0 [3:0]	43:40	unique_id
+ *   DevId_1		39:32	mfg_id [15:8]
+ *   DevId_2		31:24	mfg_id [7:0]
+ *   DevId_3		23:16	part_id [15:8]
+ *   DevId_4		15:08	part_id [7:0]
+ *   DevId_5		07:00	class_id
+ *
+ * The MIPI DisCo for SoundWire defines in addition the link_id as bits 51:48
+ */
+
+#define SDW_DISCO_LINK_ID(adr)	(((adr) >> 48) & GENMASK(3, 0))
+#define SDW_VERSION(adr)	(((adr) >> 44) & GENMASK(3, 0))
+#define SDW_UNIQUE_ID(adr)	(((adr) >> 40) & GENMASK(3, 0))
+#define SDW_MFG_ID(adr)		(((adr) >> 24) & GENMASK(15, 0))
+#define SDW_PART_ID(adr)	(((adr) >> 8) & GENMASK(15, 0))
+#define SDW_CLASS_ID(adr)	((adr) & GENMASK(7, 0))
+
 /**
  * struct sdw_slave_intr_status - Slave interrupt status
  * @control_port: control port status
-- 
2.20.1