1 files changed, 134 insertions, 0 deletions

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 4f6f682df046..78fa42589fdf 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -34,6 +34,7 @@
 #include <linux/ctype.h>
 #include <linux/slab.h>
 #include <linux/of.h>
+#include <linux/dmi.h>
 #include <sound/core.h>
 #include <sound/jack.h>
 #include <sound/pcm.h>
@@ -1888,6 +1889,139 @@ int snd_soc_runtime_set_dai_fmt(struct snd_soc_pcm_runtime *rtd,
 }
 EXPORT_SYMBOL_GPL(snd_soc_runtime_set_dai_fmt);
 
+
+/* Trim special characters, and replace '-' with '_' since '-' is used to
+ * separate different DMI fields in the card long name. Only number and
+ * alphabet characters and a few separator characters are kept.
+ */
+static void cleanup_dmi_name(char *name)
+{
+	int i, j = 0;
+
+	for (i = 0; name[i]; i++) {
+		if (isalnum(name[i]) || (name[i] == '.')
+		    || (name[i] == '_'))
+			name[j++] = name[i];
+		else if (name[i] == '-')
+			name[j++] = '_';
+	}
+
+	name[j] = '\0';
+}
+
+/**
+ * snd_soc_set_dmi_name() - Register DMI names to card
+ * @card: The card to register DMI names
+ * @flavour: The flavour "differentiator" for the card amongst its peers.
+ *
+ * An Intel machine driver may be used by many different devices but are
+ * difficult for userspace to differentiate, since machine drivers ususally
+ * use their own name as the card short name and leave the card long name
+ * blank. To differentiate such devices and fix bugs due to lack of
+ * device-specific configurations, this function allows DMI info to be used
+ * as the sound card long name, in the format of
+ * "vendor-product-version-board"
+ * (Character '-' is used to separate different DMI fields here).
+ * This will help the user space to load the device-specific Use Case Manager
+ * (UCM) configurations for the card.
+ *
+ * Possible card long names may be:
+ * DellInc.-XPS139343-01-0310JH
+ * ASUSTeKCOMPUTERINC.-T100TA-1.0-T100TA
+ * Circuitco-MinnowboardMaxD0PLATFORM-D0-MinnowBoardMAX
+ *
+ * This function also supports flavoring the card longname to provide
+ * the extra differentiation, like "vendor-product-version-board-flavor".
+ *
+ * We only keep number and alphabet characters and a few separator characters
+ * in the card long name since UCM in the user space uses the card long names
+ * as card configuration directory names and AudoConf cannot support special
+ * charactors like SPACE.
+ *
+ * Returns 0 on success, otherwise a negative error code.
+ */
+int snd_soc_set_dmi_name(struct snd_soc_card *card, const char *flavour)
+{
+	const char *vendor, *product, *product_version, *board;
+	size_t longname_buf_size = sizeof(card->snd_card->longname);
+	size_t len;
+
+	if (card->long_name)
+		return 0; /* long name already set by driver or from DMI */
+
+	/* make up dmi long name as: vendor.product.version.board */
+	vendor = dmi_get_system_info(DMI_BOARD_VENDOR);
+	if (!vendor) {
+		dev_warn(card->dev, "ASoC: no DMI vendor name!\n");
+		return 0;
+	}
+
+	snprintf(card->dmi_longname, sizeof(card->snd_card->longname),
+			 "%s", vendor);
+	cleanup_dmi_name(card->dmi_longname);
+
+	product = dmi_get_system_info(DMI_PRODUCT_NAME);
+	if (product) {
+		len = strlen(card->dmi_longname);
+		snprintf(card->dmi_longname + len,
+			 longname_buf_size - len,
+			 "-%s", product);
+
+		len++;	/* skip the separator "-" */
+		if (len < longname_buf_size)
+			cleanup_dmi_name(card->dmi_longname + len);
+
+		/* some vendors like Lenovo may only put a self-explanatory
+		 * name in the product version field
+		 */
+		product_version = dmi_get_system_info(DMI_PRODUCT_VERSION);
+		if (product_version) {
+			len = strlen(card->dmi_longname);
+			snprintf(card->dmi_longname + len,
+				 longname_buf_size - len,
+				 "-%s", product_version);
+
+			len++;
+			if (len < longname_buf_size)
+				cleanup_dmi_name(card->dmi_longname + len);
+		}
+	}
+
+	board = dmi_get_system_info(DMI_BOARD_NAME);
+	if (board) {
+		len = strlen(card->dmi_longname);
+		snprintf(card->dmi_longname + len,
+			 longname_buf_size - len,
+			 "-%s", board);
+
+		len++;
+		if (len < longname_buf_size)
+			cleanup_dmi_name(card->dmi_longname + len);
+	} else if (!product) {
+		/* fall back to using legacy name */
+		dev_warn(card->dev, "ASoC: no DMI board/product name!\n");
+		return 0;
+	}
+
+	/* Add flavour to dmi long name */
+	if (flavour) {
+		len = strlen(card->dmi_longname);
+		snprintf(card->dmi_longname + len,
+			 longname_buf_size - len,
+			 "-%s", flavour);
+
+		len++;
+		if (len < longname_buf_size)
+			cleanup_dmi_name(card->dmi_longname + len);
+	}
+
+	/* set the card long name */
+	card->long_name = card->dmi_longname;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(snd_soc_set_dmi_name);
+
 static int snd_soc_instantiate_card(struct snd_soc_card *card)
 {
 	struct snd_soc_codec *codec;