[ALSA] Control API - more robust TLV implementation

- added callback option
- added READ/WRITE/COMMAND flags to access member
- added WRITE/COMMAND ioctls
- added SNDRV_CTL_EVENT_MASK_TLV for TLV change notifications
- added TLV support to ELEM_ADD ioctl

Signed-off-by: Jaroslav Kysela <perex@suse.cz>

include/sound/asound.h

@@ -727,10 +727,15 @@ typedef int __bitwise snd_ctl_elem_iface_t;
 #define SNDRV_CTL_ELEM_ACCESS_WRITE		(1<<1)
 #define SNDRV_CTL_ELEM_ACCESS_READWRITE		(SNDRV_CTL_ELEM_ACCESS_READ|SNDRV_CTL_ELEM_ACCESS_WRITE)
 #define SNDRV_CTL_ELEM_ACCESS_VOLATILE		(1<<2)	/* control value may be changed without a notification */
-#define SNDRV_CTL_ELEM_ACCESS_TIMESTAMP		(1<<2)	/* when was control changed */
+#define SNDRV_CTL_ELEM_ACCESS_TIMESTAMP		(1<<3)	/* when was control changed */
+#define SNDRV_CTL_ELEM_ACCESS_TLV_READ		(1<<4)	/* TLV read is possible */
+#define SNDRV_CTL_ELEM_ACCESS_TLV_WRITE		(1<<5)	/* TLV write is possible */
+#define SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE	(SNDRV_CTL_ELEM_ACCESS_TLV_READ|SNDRV_CTL_ELEM_ACCESS_TLV_WRITE)
+#define SNDRV_CTL_ELEM_ACCESS_TLV_COMMAND	(1<<6)	/* TLV command is possible */
 #define SNDRV_CTL_ELEM_ACCESS_INACTIVE		(1<<8)	/* control does actually nothing, but may be updated */
 #define SNDRV_CTL_ELEM_ACCESS_LOCK		(1<<9)	/* write lock */
 #define SNDRV_CTL_ELEM_ACCESS_OWNER		(1<<10)	/* write lock owner */
+#define SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK	(1<<28)	/* kernel use a TLV callback */ 
 #define SNDRV_CTL_ELEM_ACCESS_USER		(1<<29) /* user space element */
 #define SNDRV_CTL_ELEM_ACCESS_DINDIRECT		(1<<30)	/* indirect access for matrix dimensions in the info structure */
 #define SNDRV_CTL_ELEM_ACCESS_INDIRECT		(1<<31)	/* indirect access for element value in the value structure */
@@ -838,6 +843,8 @@ enum {
 	SNDRV_CTL_IOCTL_ELEM_REPLACE = _IOWR('U', 0x18, struct snd_ctl_elem_info),
 	SNDRV_CTL_IOCTL_ELEM_REMOVE = _IOWR('U', 0x19, struct snd_ctl_elem_id),
 	SNDRV_CTL_IOCTL_TLV_READ = _IOWR('U', 0x1a, struct snd_ctl_tlv),
+	SNDRV_CTL_IOCTL_TLV_WRITE = _IOWR('U', 0x1b, struct snd_ctl_tlv),
+	SNDRV_CTL_IOCTL_TLV_COMMAND = _IOWR('U', 0x1c, struct snd_ctl_tlv),
 	SNDRV_CTL_IOCTL_HWDEP_NEXT_DEVICE = _IOWR('U', 0x20, int),
 	SNDRV_CTL_IOCTL_HWDEP_INFO = _IOR('U', 0x21, struct snd_hwdep_info),
 	SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE = _IOR('U', 0x30, int),
@@ -862,6 +869,7 @@ enum sndrv_ctl_event_type {
 #define SNDRV_CTL_EVENT_MASK_VALUE	(1<<0)	/* element value was changed */
 #define SNDRV_CTL_EVENT_MASK_INFO	(1<<1)	/* element info was changed */
 #define SNDRV_CTL_EVENT_MASK_ADD	(1<<2)	/* element was added */
+#define SNDRV_CTL_EVENT_MASK_TLV	(1<<3)	/* element TLV tree was changed */
 #define SNDRV_CTL_EVENT_MASK_REMOVE	(~0U)	/* element was removed */
 
 struct snd_ctl_event {

include/sound/control.h

@@ -30,6 +30,11 @@ struct snd_kcontrol;
 typedef int (snd_kcontrol_info_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_info * uinfo);
 typedef int (snd_kcontrol_get_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
 typedef int (snd_kcontrol_put_t) (struct snd_kcontrol * kcontrol, struct snd_ctl_elem_value * ucontrol);
+typedef int (snd_kcontrol_tlv_rw_t)(struct snd_kcontrol *kcontrol,
+				    int op_flag, /* 0=read,1=write,-1=command */
+				    unsigned int size,
+				    unsigned int __user *tlv);
+
 
 struct snd_kcontrol_new {
 	snd_ctl_elem_iface_t iface;	/* interface identifier */
@@ -42,7 +47,10 @@ struct snd_kcontrol_new {
 	snd_kcontrol_info_t *info;
 	snd_kcontrol_get_t *get;
 	snd_kcontrol_put_t *put;
-	unsigned int *tlv;
+	union {
+		snd_kcontrol_tlv_rw_t *c;
+		unsigned int *p;
+	} tlv;
 	unsigned long private_value;
 };
 
@@ -59,7 +67,11 @@ struct snd_kcontrol {
 	snd_kcontrol_info_t *info;
 	snd_kcontrol_get_t *get;
 	snd_kcontrol_put_t *put;
-	unsigned int *tlv;
+	snd_kcontrol_tlv_rw_t *tlv_rw;
+	union {
+		snd_kcontrol_tlv_rw_t *c;
+		unsigned int *p;
+	} tlv;
 	unsigned long private_value;
 	void *private_data;
 	void (*private_free)(struct snd_kcontrol *kcontrol);