/* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include <linux/init.h> #include <linux/slab.h> #include <linux/usb.h> #include "usbaudio.h" #include "helper.h" #include "quirks.h" /* * combine bytes and get an integer value */ unsigned int snd_usb_combine_bytes(unsigned char *bytes, int size) { switch (size) { case 1: return *bytes; case 2: return combine_word(bytes); case 3: return combine_triple(bytes); case 4: return combine_quad(bytes); default: return 0; } } /* * parse descriptor buffer and return the pointer starting the given * descriptor type. */ void *snd_usb_find_desc(void *descstart, int desclen, void *after, u8 dtype) { u8 *p, *end, *next; p = descstart; end = p + desclen; for (; p < end;) { if (p[0] < 2) return NULL; next = p + p[0]; if (next > end) return NULL; if (p[1] == dtype && (!after || (void *)p > after)) { return p; } p = next; } return NULL; } /* * find a class-specified interface descriptor with the given subtype. */ void *snd_usb_find_csint_desc(void *buffer, int buflen, void *after, u8 dsubtype) { unsigned char *p = after; while ((p = snd_usb_find_desc(buffer, buflen, p, USB_DT_CS_INTERFACE)) != NULL) { if (p[0] >= 3 && p[2] == dsubtype) return p; } return NULL; } /* * Wrapper for usb_control_msg(). * Allocates a temp buffer to prevent dmaing from/to the stack. */ int snd_usb_ctl_msg(struct usb_device *dev, unsigned int pipe, __u8 request, __u8 requesttype, __u16 value, __u16 index, void *data, __u16 size) { int err; void *buf = NULL; int timeout; if (size > 0) { buf = kmemdup(data, size, GFP_KERNEL); if (!buf) return -ENOMEM; } if (requesttype & USB_DIR_IN) timeout = USB_CTRL_GET_TIMEOUT; else timeout = USB_CTRL_SET_TIMEOUT; err = usb_control_msg(dev, pipe, request, requesttype, value, index, buf, size, timeout); if (size > 0) { memcpy(data, buf, size); kfree(buf); } snd_usb_ctl_msg_quirk(dev, pipe, request, requesttype, value, index, data, size); return err; } unsigned char snd_usb_parse_datainterval(struct snd_usb_audio *chip, struct usb_host_interface *alts) { switch (snd_usb_get_speed(chip->dev)) { case USB_SPEED_HIGH: case USB_SPEED_WIRELESS: case USB_SPEED_SUPER: case USB_SPEED_SUPER_PLUS: if (get_endpoint(alts, 0)->bInterval >= 1 && get_endpoint(alts, 0)->bInterval <= 4) return get_endpoint(alts, 0)->bInterval - 1; break; default: break; } return 0; }