[alsa-devel] [PATCH 1/2] ASoC: core: Add API to use DMI name in sound card long name

[mengdong.lin at linux.intel.com]

From: Liam Girdwood <liam.r.girdwood at linux.intel.com>

Intel DSP platform drivers are used by many different devices but are
difficult for userspace to differentiate. This patch adds an API to allow
the DMI name to be used in the sound card long name, thereby helping
userspace load the correct UCM configuration. Usually machine drivers
uses their own name as the sound card name (short name), and leave the
long name and driver name blank. This API will append the DMI info
like vendor, product and board info, to the card name to make up the card
long name. If the machine driver has already explicitly set the long name,
this API will do nothing.

This patch also allows for further differentiation as many devices that
share the same DMI name i.e. Minnowboards, UP boards may be configured
with different codecs or firmwares. The API supports flavoring the DMI
name into the card longname to provide the extra differentiation required
for these devices.

Signed-off-by: Liam Girdwood <liam.r.girdwood at linux.intel.com>
Signed-off-by: Mengdong Lin <mengdong.lin at linux.intel.com>

diff --git a/include/sound/soc.h b/include/sound/soc.h
index 795e6c4..e4f1844 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -497,6 +497,8 @@ void snd_soc_runtime_deactivate(struct snd_soc_pcm_runtime *rtd, int stream);
 int snd_soc_runtime_set_dai_fmt(struct snd_soc_pcm_runtime *rtd,
 	unsigned int dai_fmt);
 
+int snd_soc_set_dmi_name(struct snd_soc_card *card, const char *flavour);
+
 /* Utility functions to get clock rates from various things */
 int snd_soc_calc_frame_size(int sample_size, int channels, int tdm_slots);
 int snd_soc_params_to_frame_size(struct snd_pcm_hw_params *params);
@@ -1094,6 +1096,8 @@ struct snd_soc_card {
 	const char *name;
 	const char *long_name;
 	const char *driver_name;
+	char dmi_longname[80];
+
 	struct device *dev;
 	struct snd_card *snd_card;
 	struct module *owner;
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index aaab26a..8bcf241 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>
@@ -1886,6 +1887,86 @@ int snd_soc_runtime_set_dai_fmt(struct snd_soc_pcm_runtime *rtd,
 }
 EXPORT_SYMBOL_GPL(snd_soc_runtime_set_dai_fmt);
 
+/**
+ * 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.
+ *
+ * Intel DSP platform drivers are used by many different devices but are
+ * difficult for userspace to differentiate, since machine drivers ususally
+ * use their own name as the card name (short name) and leave the card long
+ * name blank. This function will allow DMI info to be used in the sound
+ * card long name, thereby helping userspace load the correct UCM (Use Case
+ * Manager) configuration.
+ * Possible card long names may be:
+ * broadwell-rt286-Dell Inc.-XPS 13 9343-0310JH
+ * broadwell-rt286-Intel Corp.-Broadwell Client platform-Wilson Beach SDS
+ * bytcr-rt5640-ASUSTeK COMPUTER INC.-T100TA-T100TA
+ * bytcr-rt5651-Circuitco-Minnowboard Max D0 PLATFORM-MinnowBoard MAX
+ *
+ * This function also supports flavoring the card longname to provide
+ * the extra differentiation.
+ *
+ * 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, *board;
+
+	if (card->long_name)
+		return 0; /* long name already set by driver or from DMI */
+
+	vendor = dmi_get_system_info(DMI_BOARD_VENDOR);
+	if (!vendor) {
+		dev_warn(card->dev, "ASoC: no DMI vendor name!\n");
+		return 0;
+	}
+
+	product = dmi_get_system_info(DMI_PRODUCT_NAME);
+	board = dmi_get_system_info(DMI_BOARD_NAME);
+	if (!board && !product) {
+		/* fall back to using legacy name */
+		dev_warn(card->dev, "ASoC: no DMI board/product name!\n");
+		return 0;
+	}
+
+	/* make up dmi long name as:
+	 * card name (usually machine driver name) -vendor -product -board
+	 */
+	snprintf(card->dmi_longname, sizeof(card->snd_card->longname),
+			"%s-%s", card->name, vendor);
+
+	if (product) {
+		strncat(card->dmi_longname, "-",
+			sizeof(card->snd_card->longname));
+		strncat(card->dmi_longname, product,
+			sizeof(card->snd_card->longname));
+	}
+
+	if (board) {
+		strncat(card->dmi_longname, "-",
+			sizeof(card->snd_card->longname));
+		strncat(card->dmi_longname, board,
+			sizeof(card->snd_card->longname));
+	}
+
+
+	/* Add flavour to dmi long name */
+	if (flavour) {
+		strncat(card->dmi_longname, "-",
+			sizeof(card->snd_card->longname));
+		strncat(card->dmi_longname, flavour,
+			sizeof(card->snd_card->longname));
+	}
+
+	/* set 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;
-- 
2.5.0