From 6639b6c2367f884ca172b78d69f7da17bfab2e5e Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Fri, 29 Apr 2005 16:26:14 +0200 Subject: [ALSA] usb-audio - add mixer control notifications USB generic driver Add support for the optional status interrupt endpoint in audio control interfaces, and translate USB status notifications into ALSA mixer control notifications. Signed-off-by: Clemens Ladisch --- sound/usb/usbmixer.c | 101 +++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 98 insertions(+), 3 deletions(-) (limited to 'sound/usb/usbmixer.c') diff --git a/sound/usb/usbmixer.c b/sound/usb/usbmixer.c index 7bbccebd76c..dd045ea6fb0 100644 --- a/sound/usb/usbmixer.c +++ b/sound/usb/usbmixer.c @@ -55,6 +55,8 @@ struct usb_mixer_interface { unsigned int ctrlif; struct list_head list; unsigned int ignore_ctl_error; + struct urb *urb; + usb_mixer_elem_info_t **id_elems; /* array[256], indexed by unit id */ }; @@ -83,13 +85,15 @@ struct usb_mixer_build { struct usb_mixer_elem_info { struct usb_mixer_interface *mixer; + usb_mixer_elem_info_t *next_id_elem; /* list of controls with same id */ + snd_ctl_elem_id_t *elem_id; unsigned int id; unsigned int control; /* CS or ICN (high byte) */ unsigned int cmask; /* channel mask bitmap: 0 = master */ int channels; int val_type; int min, max, res; - unsigned int initialized: 1; + u8 initialized; }; @@ -414,6 +418,7 @@ static int check_matrix_bitmap(unsigned char *bmap, int ich, int och, int num_ou static int add_control_to_empty(mixer_build_t *state, snd_kcontrol_t *kctl) { + usb_mixer_elem_info_t *cval = kctl->private_data; int err; while (snd_ctl_find_id(state->chip->card, &kctl->id)) @@ -421,8 +426,12 @@ static int add_control_to_empty(mixer_build_t *state, snd_kcontrol_t *kctl) if ((err = snd_ctl_add(state->chip->card, kctl)) < 0) { snd_printd(KERN_ERR "cannot add control (err = %d)\n", err); snd_ctl_free_one(kctl); + return err; } - return err; + cval->elem_id = &kctl->id; + cval->next_id_elem = state->mixer->id_elems[cval->id]; + state->mixer->id_elems[cval->id] = cval; + return 0; } @@ -1522,6 +1531,11 @@ static int parse_audio_unit(mixer_build_t *state, int unitid) static void snd_usb_mixer_free(struct usb_mixer_interface *mixer) { + kfree(mixer->id_elems); + if (mixer->urb) { + kfree(mixer->urb->transfer_buffer); + usb_free_urb(mixer->urb); + } kfree(mixer); } @@ -1580,6 +1594,76 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer) return 0; } +static void snd_usb_mixer_notify_id(struct usb_mixer_interface *mixer, + int unitid) +{ + usb_mixer_elem_info_t *info; + + for (info = mixer->id_elems[unitid]; info; info = info->next_id_elem) + snd_ctl_notify(mixer->chip->card, SNDRV_CTL_EVENT_MASK_VALUE, + info->elem_id); +} + +static void snd_usb_mixer_status_complete(struct urb *urb, struct pt_regs *regs) +{ + struct usb_mixer_interface *mixer = urb->context; + + if (urb->status == 0) { + u8 *buf = urb->transfer_buffer; + int i; + + for (i = urb->actual_length; i >= 2; buf += 2, i -= 2) { + snd_printd(KERN_DEBUG "status interrupt: %02x %02x\n", + buf[0], buf[1]); + /* ignore any notifications not from the control interface */ + if ((buf[0] & 0x0f) != 0) + continue; + if (!(buf[0] & 0x40)) + snd_usb_mixer_notify_id(mixer, buf[1]); + } + } + if (urb->status != -ENOENT && urb->status != -ECONNRESET) { + urb->dev = mixer->chip->dev; + usb_submit_urb(urb, GFP_ATOMIC); + } +} + +/* create the handler for the optional status interrupt endpoint */ +static int snd_usb_mixer_status_create(struct usb_mixer_interface *mixer) +{ + struct usb_host_interface *hostif; + struct usb_endpoint_descriptor *ep; + void *transfer_buffer; + int buffer_length; + unsigned int epnum; + + hostif = &usb_ifnum_to_if(mixer->chip->dev, mixer->ctrlif)->altsetting[0]; + /* we need one interrupt input endpoint */ + if (get_iface_desc(hostif)->bNumEndpoints < 1) + return 0; + ep = get_endpoint(hostif, 0); + if ((ep->bEndpointAddress & USB_ENDPOINT_DIR_MASK) != USB_DIR_IN || + (ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) != USB_ENDPOINT_XFER_INT) + return 0; + + epnum = ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK; + buffer_length = le16_to_cpu(ep->wMaxPacketSize); + transfer_buffer = kmalloc(buffer_length, GFP_KERNEL); + if (!transfer_buffer) + return -ENOMEM; + mixer->urb = usb_alloc_urb(0, GFP_KERNEL); + if (!mixer->urb) { + kfree(transfer_buffer); + return -ENOMEM; + } + usb_fill_int_urb(mixer->urb, mixer->chip->dev, + usb_rcvintpipe(mixer->chip->dev, epnum), + transfer_buffer, buffer_length, + snd_usb_mixer_status_complete, mixer, ep->bInterval); + usb_submit_urb(mixer->urb, GFP_KERNEL); + return 0; +} + int snd_usb_create_mixer(snd_usb_audio_t *chip, int ctrlif) { static snd_device_ops_t dev_ops = { @@ -1598,8 +1682,14 @@ int snd_usb_create_mixer(snd_usb_audio_t *chip, int ctrlif) #ifdef IGNORE_CTL_ERROR mixer->ignore_ctl_error = 1; #endif + mixer->id_elems = kcalloc(256, sizeof(*mixer->id_elems), GFP_KERNEL); + if (!mixer->id_elems) { + kfree(mixer); + return -ENOMEM; + } - if ((err = snd_usb_mixer_controls(mixer)) < 0) { + if ((err = snd_usb_mixer_controls(mixer)) < 0 || + (err = snd_usb_mixer_status_create(mixer)) < 0) { snd_usb_mixer_free(mixer); return err; } @@ -1615,4 +1705,9 @@ int snd_usb_create_mixer(snd_usb_audio_t *chip, int ctrlif) void snd_usb_mixer_disconnect(struct list_head *p) { + struct usb_mixer_interface *mixer; + + mixer = list_entry(p, struct usb_mixer_interface, list); + if (mixer->urb) + usb_kill_urb(mixer->urb); } -- cgit v1.2.3