Find codec driver by SoundWire address instead of guessing the name

drivers/soundwire/bus.c

@@ -794,22 +794,23 @@ static int sdw_assign_device_num(struct sdw_slave *slave)
 	return 0;
 }
 
-void sdw_extract_slave_id(struct sdw_bus *bus,
-			  u64 addr, struct sdw_slave_id *id)
+void sdw_extract_slave_id(u64 addr, struct sdw_slave_id *id)
 {
-	dev_dbg(bus->dev, "SDW Slave Addr: %llx\n", addr);
-
 	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);
+}
+EXPORT_SYMBOL(sdw_extract_slave_id);
 
-	dev_dbg(bus->dev,
+void sdw_debug_log_slave_id(struct device *dev, const struct sdw_slave_id *id)
+{
+	dev_dbg(dev,
 		"SDW Slave class_id 0x%02x, mfg_id 0x%04x, part_id 0x%04x, unique_id 0x%x, version 0x%x\n",
 		id->class_id, id->mfg_id, id->part_id, id->unique_id, id->sdw_version);
 }
-EXPORT_SYMBOL(sdw_extract_slave_id);
+EXPORT_SYMBOL(sdw_debug_log_slave_id);
 
 bool is_clock_scaling_supported_by_slave(struct sdw_slave *slave)
 {
@@ -862,7 +863,8 @@ static int sdw_program_device_num(struct sdw_bus *bus, bool *programmed)
 			((u64)buf[2] << 24) | ((u64)buf[1] << 32) |
 			((u64)buf[0] << 40);
 
-		sdw_extract_slave_id(bus, addr, &id);
+		sdw_extract_slave_id(addr, &id);
+		sdw_debug_log_slave_id(bus->dev, &id);
 
 		found = false;
 		/* Now compare with entries */

drivers/soundwire/bus.h

@@ -19,8 +19,6 @@ static inline int sdw_acpi_find_slaves(struct sdw_bus *bus)
 #endif
 
 int sdw_of_find_slaves(struct sdw_bus *bus);
-void sdw_extract_slave_id(struct sdw_bus *bus,
-			  u64 addr, struct sdw_slave_id *id);
 int sdw_slave_add(struct sdw_bus *bus, struct sdw_slave_id *id,
 		  struct fwnode_handle *fwnode);
 int sdw_master_device_add(struct sdw_bus *bus, struct device *parent,

drivers/soundwire/qcom.c

@@ -662,7 +662,8 @@ static int qcom_swrm_enumerate(struct sdw_bus *bus)
 			((u64)buf1[2] << 24) | ((u64)buf1[1] << 32) |
 			((u64)buf1[0] << 40);
 
-		sdw_extract_slave_id(bus, addr, &id);
+		sdw_extract_slave_id(addr, &id);
+		sdw_debug_log_slave_id(bus->dev, &id);
 		found = false;
 		ctrl->clock_stop_not_supported = false;
 		/* Now compare with entries */

drivers/soundwire/slave.c

@@ -135,7 +135,8 @@ static bool find_slave(struct sdw_bus *bus,
 	if (link_id != bus->link_id)
 		return false;
 
-	sdw_extract_slave_id(bus, addr, id);
+	sdw_extract_slave_id(addr, id);
+	sdw_debug_log_slave_id(bus->dev, id);
 
 	return true;
 }

include/linux/soundwire/sdw.h

@@ -1089,13 +1089,15 @@ int sdw_bus_clk_stop(struct sdw_bus *bus);
 int sdw_bus_exit_clk_stop(struct sdw_bus *bus);
 
 int sdw_compare_devid(struct sdw_slave *slave, struct sdw_slave_id id);
-void sdw_extract_slave_id(struct sdw_bus *bus, u64 addr, struct sdw_slave_id *id);
+void sdw_extract_slave_id(u64 addr, struct sdw_slave_id *id);
 bool is_clock_scaling_supported_by_slave(struct sdw_slave *slave);
 
 int sdw_bpt_send_async(struct sdw_bus *bus, struct sdw_slave *slave, struct sdw_bpt_msg *msg);
 int sdw_bpt_wait(struct sdw_bus *bus, struct sdw_slave *slave, struct sdw_bpt_msg *msg);
 int sdw_bpt_send_sync(struct sdw_bus *bus, struct sdw_slave *slave, struct sdw_bpt_msg *msg);
 
+void sdw_debug_log_slave_id(struct device *dev, const struct sdw_slave_id *id);
+
 #if IS_ENABLED(CONFIG_SOUNDWIRE)
 
 int sdw_stream_add_slave(struct sdw_slave *slave,
@@ -1216,6 +1218,14 @@ static inline int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u
 	return -EINVAL;
 }
 
+static inline void sdw_extract_slave_id(u64 addr, struct sdw_slave_id *id)
+{
+}
+
+static inline void sdw_debug_log_slave_id(struct device *dev, const struct sdw_slave_id *id)
+{
+}
+
 #endif /* CONFIG_SOUNDWIRE */
 
 /**

include/sound/soc.h

@@ -469,6 +469,10 @@ struct snd_soc_component *snd_soc_lookup_component(struct device *dev,
 						   const char *driver_name);
 struct snd_soc_component *snd_soc_lookup_component_by_name(const char *component_name);
 
+typedef int (*snd_soc_component_walk_fn)(struct snd_soc_component *component, void *context);
+struct snd_soc_component *snd_soc_lookup_component_walk(snd_soc_component_walk_fn cb,
+							void *context);
+
 int soc_new_pcm(struct snd_soc_pcm_runtime *rtd);
 #ifdef CONFIG_SND_SOC_COMPRESS
 int snd_soc_new_compress(struct snd_soc_pcm_runtime *rtd);

include/sound/soc_sdw_utils.h

@@ -140,6 +140,9 @@ int asoc_sdw_hw_params(struct snd_pcm_substream *substream,
 int asoc_sdw_hw_free(struct snd_pcm_substream *substream);
 void asoc_sdw_shutdown(struct snd_pcm_substream *substream);
 
+struct snd_soc_component *asoc_sdw_find_component(const struct asoc_sdw_dai_info *dai_info,
+						  const struct snd_soc_acpi_link_adr *adr_link,
+						  int adr_index);
 const char *asoc_sdw_get_codec_name(struct device *dev,
 				    const struct asoc_sdw_dai_info *dai_info,
 				    const struct snd_soc_acpi_link_adr *adr_link,

sound/soc/sdw_utils/soc_sdw_utils.c

@@ -1635,6 +1635,50 @@ static bool asoc_sdw_is_unique_device(const struct snd_soc_acpi_link_adr *adr_li
 	return true;
 }
 
+struct asoc_sdw_find_info {
+	const char *subname;
+	struct sdw_slave_id id;
+};
+
+static int asoc_sdw_find_component_cb(struct snd_soc_component *component, void *context)
+{
+	const struct asoc_sdw_find_info *info = context;
+	struct device *dev = component->dev;
+
+	if (!is_sdw_slave(dev)) {
+		dev = component->dev->parent;
+		if (!dev || !is_sdw_slave(dev))
+			return 0;
+	}
+
+	if (sdw_compare_devid(dev_to_sdw_dev(dev), info->id) != 0)
+		return 0;
+
+	if (info->subname && !strstr(component->name, info->subname))
+		return 0;
+
+	return 1;
+}
+
+struct snd_soc_component *asoc_sdw_find_component(const struct asoc_sdw_dai_info *dai_info,
+						  const struct snd_soc_acpi_link_adr *adr_link,
+						  int adr_index)
+{
+	u64 adr = adr_link->adr_d[adr_index].adr;
+	struct asoc_sdw_find_info info;
+	struct snd_soc_component *component;
+
+	sdw_extract_slave_id(adr, &info.id);
+	info.subname = dai_info->codec_name;
+
+	component = snd_soc_lookup_component_walk(asoc_sdw_find_component_cb, &info);
+	if (IS_ERR(component))
+		return NULL;
+
+	return component;
+}
+EXPORT_SYMBOL_NS(asoc_sdw_find_component, "SND_SOC_SDW_UTILS");
+
 static const char *_asoc_sdw_get_codec_name(struct device *dev,
 					    const struct snd_soc_acpi_link_adr *adr_link,
 					    int adr_index)
@@ -1661,22 +1705,23 @@ const char *asoc_sdw_get_codec_name(struct device *dev,
 				    const struct snd_soc_acpi_link_adr *adr_link,
 				    int adr_index)
 {
-	if (dai_info->codec_name) {
-		struct snd_soc_component *component;
-
-		component = snd_soc_lookup_component_by_name(dai_info->codec_name);
-		if (component) {
-			dev_dbg(dev, "%s found component %s for codec_name %s\n",
-				__func__, component->name, dai_info->codec_name);
-			return devm_kstrdup(dev, component->name, GFP_KERNEL);
-		} else {
-			dev_dbg(dev, "%s component %s is not registered yet\n",
-				__func__, dai_info->codec_name);
-			return ERR_PTR(-EPROBE_DEFER);
-		}
+	struct snd_soc_component *component;
+
+	component = asoc_sdw_find_component(dai_info, adr_link, adr_index);
+	if (!component) {
+		dev_dbg(dev, "%s component for addr %013llx subname '%s' is not registered yet\n",
+			__func__,
+			adr_link->adr_d[adr_index].adr,
+			dai_info->codec_name);
+		return ERR_PTR(-EPROBE_DEFER);
 	}
 
-	return _asoc_sdw_get_codec_name(dev, adr_link, adr_index);
+	dev_dbg(dev, "%s found component %s for adr %013llx subname '%s'\n",
+		__func__, component->name,
+		adr_link->adr_d[adr_index].adr,
+		dai_info->codec_name);
+
+	return devm_kstrdup(dev, component->name, GFP_KERNEL);
 }
 EXPORT_SYMBOL_NS(asoc_sdw_get_codec_name, "SND_SOC_SDW_UTILS");
 

sound/soc/soc-core.c

@@ -406,6 +406,39 @@ struct snd_soc_component *snd_soc_lookup_component_by_name(const char *component
 }
 EXPORT_SYMBOL_GPL(snd_soc_lookup_component_by_name);
 
+/**
+ * snd_soc_lookup_component_walk - component lookup using callback.
+ * @cb: function to call for each component.
+ * @context: caller-defined value to be passed to callback function. Can
+ *           be NULL.
+ *
+ * Iterate over snd_soc_component items, calling @cb for each, until @cb
+ * returns a non-zero value. The @context pointer is a value defined by the
+ * caller and is passed to @cb.
+ *
+ * Return: struct snd_soc_component* if @cb returned >0.
+ *	   ERR_PTR(-ENOENT) if @cb returned 0 on every call.
+ * 	   ERR_PTR of value returned by @cb if @cb returned <0.
+ */
+struct snd_soc_component *snd_soc_lookup_component_walk(snd_soc_component_walk_fn cb,
+							void *context)
+{
+	struct snd_soc_component *component;
+	int ret;
+
+	guard(mutex)(&client_mutex);
+	for_each_component(component) {
+		ret = (cb)(component, context);
+		if (ret > 0)
+			return component;
+		if (ret < 0)
+			return ERR_PTR(ret);
+	}
+
+	return ERR_PTR(-ENOENT);
+}
+EXPORT_SYMBOL_GPL(snd_soc_lookup_component_walk);
+
 struct snd_soc_pcm_runtime
 *snd_soc_get_pcm_runtime(struct snd_soc_card *card,
 			 struct snd_soc_dai_link *dai_link)