sound/usb/6fire/comm.c

   1 /*
   2  * Linux driver for TerraTec DMX 6Fire USB
   3  *
   4  * Device communications
   5  *
   6  * Author:      Torsten Schenk <torsten.schenk@zoho.com>
   7  * Created:     Jan 01, 2011
   8  * Version:     0.3.0
   9  * Copyright:   (C) Torsten Schenk
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  */
  16
  17 #include "comm.h"
  18 #include "chip.h"
  19 #include "midi.h"
  20
  21 enum {
  22         COMM_EP = 1,
  23         COMM_FPGA_EP = 2
  24 };
  25
  26 static void usb6fire_comm_init_urb(struct comm_runtime *rt, struct urb *urb,
  27                 u8 *buffer, void *context, void(*handler)(struct urb *urb))
  28 {
  29         usb_init_urb(urb);
  30         urb->transfer_buffer = buffer;
  31         urb->pipe = usb_sndintpipe(rt->chip->dev, COMM_EP);
  32         urb->complete = handler;
  33         urb->context = context;
  34         urb->interval = 1;
  35         urb->dev = rt->chip->dev;
  36 }
  37
  38 static void usb6fire_comm_receiver_handler(struct urb *urb)
  39 {
  40         struct comm_runtime *rt = urb->context;
  41         struct midi_runtime *midi_rt = rt->chip->midi;
  42
  43         if (!urb->status) {
  44                 if (rt->receiver_buffer[0] == 0x10) /* midi in event */
  45                         if (midi_rt)
  46                                 midi_rt->in_received(midi_rt,
  47                                                 rt->receiver_buffer + 2,
  48                                                 rt->receiver_buffer[1]);
  49         }
  50
  51         if (!rt->chip->shutdown) {
  52                 urb->status = 0;
  53                 urb->actual_length = 0;
  54                 if (usb_submit_urb(urb, GFP_ATOMIC) < 0)
  55                         snd_printk(KERN_WARNING PREFIX
  56                                         "comm data receiver aborted.\n");
  57         }
  58 }
  59
  60 static void usb6fire_comm_init_buffer(u8 *buffer, u8 id, u8 request,
  61                 u8 reg, u8 vl, u8 vh)
  62 {
  63         buffer[0] = 0x01;
  64         buffer[2] = request;
  65         buffer[3] = id;
  66         switch (request) {
  67         case 0x02:
  68                 buffer[1] = 0x05; /* length (starting at buffer[2]) */
  69                 buffer[4] = reg;
  70                 buffer[5] = vl;
  71                 buffer[6] = vh;
  72                 break;
  73
  74         case 0x12:
  75                 buffer[1] = 0x0b; /* length (starting at buffer[2]) */
  76                 buffer[4] = 0x00;
  77                 buffer[5] = 0x18;
  78                 buffer[6] = 0x05;
  79                 buffer[7] = 0x00;
  80                 buffer[8] = 0x01;
  81                 buffer[9] = 0x00;
  82                 buffer[10] = 0x9e;
  83                 buffer[11] = reg;
  84                 buffer[12] = vl;
  85                 break;
  86
  87         case 0x20:
  88         case 0x21:
  89         case 0x22:
  90                 buffer[1] = 0x04;
  91                 buffer[4] = reg;
  92                 buffer[5] = vl;
  93                 break;
  94         }
  95 }
  96
  97 static int usb6fire_comm_send_buffer(u8 *buffer, struct usb_device *dev)
  98 {
  99         int ret;
 100         int actual_len;
 101
 102         ret = usb_interrupt_msg(dev, usb_sndintpipe(dev, COMM_EP),
 103                         buffer, buffer[1] + 2, &actual_len, HZ);
 104         if (ret < 0)
 105                 return ret;
 106         else if (actual_len != buffer[1] + 2)
 107                 return -EIO;
 108         return 0;
 109 }
 110
 111 static int usb6fire_comm_write8(struct comm_runtime *rt, u8 request,
 112                 u8 reg, u8 value)
 113 {
 114         u8 buffer[13]; /* 13: maximum length of message */
 115
 116         usb6fire_comm_init_buffer(buffer, 0x00, request, reg, value, 0x00);
 117         return usb6fire_comm_send_buffer(buffer, rt->chip->dev);
 118 }
 119
 120 static int usb6fire_comm_write16(struct comm_runtime *rt, u8 request,
 121                 u8 reg, u8 vl, u8 vh)
 122 {
 123         u8 buffer[13]; /* 13: maximum length of message */
 124
 125         usb6fire_comm_init_buffer(buffer, 0x00, request, reg, vl, vh);
 126         return usb6fire_comm_send_buffer(buffer, rt->chip->dev);
 127 }
 128
 129 int __devinit usb6fire_comm_init(struct sfire_chip *chip)
 130 {
 131         struct comm_runtime *rt = kzalloc(sizeof(struct comm_runtime),
 132                         GFP_KERNEL);
 133         struct urb *urb = &rt->receiver;
 134         int ret;
 135
 136         if (!rt)
 137                 return -ENOMEM;
 138
 139         rt->serial = 1;
 140         rt->chip = chip;
 141         usb_init_urb(urb);
 142         rt->init_urb = usb6fire_comm_init_urb;
 143         rt->write8 = usb6fire_comm_write8;
 144         rt->write16 = usb6fire_comm_write16;
 145
 146         /* submit an urb that receives communication data from device */
 147         urb->transfer_buffer = rt->receiver_buffer;
 148         urb->transfer_buffer_length = COMM_RECEIVER_BUFSIZE;
 149         urb->pipe = usb_rcvintpipe(chip->dev, COMM_EP);
 150         urb->dev = chip->dev;
 151         urb->complete = usb6fire_comm_receiver_handler;
 152         urb->context = rt;
 153         urb->interval = 1;
 154         ret = usb_submit_urb(urb, GFP_KERNEL);
 155         if (ret < 0) {
 156                 kfree(rt);
 157                 snd_printk(KERN_ERR PREFIX "cannot create comm data receiver.");
 158                 return ret;
 159         }
 160         chip->comm = rt;
 161         return 0;
 162 }
 163
 164 void usb6fire_comm_abort(struct sfire_chip *chip)
 165 {
 166         struct comm_runtime *rt = chip->comm;
 167
 168         if (rt)
 169                 usb_poison_urb(&rt->receiver);
 170 }
 171
 172 void usb6fire_comm_destroy(struct sfire_chip *chip)
 173 {
 174         kfree(chip->comm);
 175         chip->comm = NULL;
 176 }