kernel/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  * Copyright:   (C) Torsten Schenk
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  */
  15
  16 #include "comm.h"
  17 #include "chip.h"
  18 #include "midi.h"
  19
  20 enum {
  21         COMM_EP = 1,
  22         COMM_FPGA_EP = 2
  23 };
  24
  25 static void usb6fire_comm_init_urb(struct comm_runtime *rt, struct urb *urb,
  26                 u8 *buffer, void *context, void(*handler)(struct urb *urb))
  27 {
  28         usb_init_urb(urb);
  29         urb->transfer_buffer = buffer;
  30         urb->pipe = usb_sndintpipe(rt->chip->dev, COMM_EP);
  31         urb->complete = handler;
  32         urb->context = context;
  33         urb->interval = 1;
  34         urb->dev = rt->chip->dev;
  35 }
  36
  37 static void usb6fire_comm_receiver_handler(struct urb *urb)
  38 {
  39         struct comm_runtime *rt = urb->context;
  40         struct midi_runtime *midi_rt = rt->chip->midi;
  41
  42         if (!urb->status) {
  43                 if (rt->receiver_buffer[0] == 0x10) /* midi in event */
  44                         if (midi_rt)
  45                                 midi_rt->in_received(midi_rt,
  46                                                 rt->receiver_buffer + 2,
  47                                                 rt->receiver_buffer[1]);
  48         }
  49
  50         if (!rt->chip->shutdown) {
  51                 urb->status = 0;
  52                 urb->actual_length = 0;
  53                 if (usb_submit_urb(urb, GFP_ATOMIC) < 0)
  54                         dev_warn(&urb->dev->dev,
  55                                         "comm data receiver aborted.\n");
  56         }
  57 }
  58
  59 static void usb6fire_comm_init_buffer(u8 *buffer, u8 id, u8 request,
  60                 u8 reg, u8 vl, u8 vh)
  61 {
  62         buffer[0] = 0x01;
  63         buffer[2] = request;
  64         buffer[3] = id;
  65         switch (request) {
  66         case 0x02:
  67                 buffer[1] = 0x05; /* length (starting at buffer[2]) */
  68                 buffer[4] = reg;
  69                 buffer[5] = vl;
  70                 buffer[6] = vh;
  71                 break;
  72
  73         case 0x12:
  74                 buffer[1] = 0x0b; /* length (starting at buffer[2]) */
  75                 buffer[4] = 0x00;
  76                 buffer[5] = 0x18;
  77                 buffer[6] = 0x05;
  78                 buffer[7] = 0x00;
  79                 buffer[8] = 0x01;
  80                 buffer[9] = 0x00;
  81                 buffer[10] = 0x9e;
  82                 buffer[11] = reg;
  83                 buffer[12] = vl;
  84                 break;
  85
  86         case 0x20:
  87         case 0x21:
  88         case 0x22:
  89                 buffer[1] = 0x04;
  90                 buffer[4] = reg;
  91                 buffer[5] = vl;
  92                 break;
  93         }
  94 }
  95
  96 static int usb6fire_comm_send_buffer(u8 *buffer, struct usb_device *dev)
  97 {
  98         int ret;
  99         int actual_len;
 100
 101         ret = usb_interrupt_msg(dev, usb_sndintpipe(dev, COMM_EP),
 102                         buffer, buffer[1] + 2, &actual_len, HZ);
 103         if (ret < 0)
 104                 return ret;
 105         else if (actual_len != buffer[1] + 2)
 106                 return -EIO;
 107         return 0;
 108 }
 109
 110 static int usb6fire_comm_write8(struct comm_runtime *rt, u8 request,
 111                 u8 reg, u8 value)
 112 {
 113         u8 *buffer;
 114         int ret;
 115
 116         /* 13: maximum length of message */
 117         buffer = kmalloc(13, GFP_KERNEL);
 118         if (!buffer)
 119                 return -ENOMEM;
 120
 121         usb6fire_comm_init_buffer(buffer, 0x00, request, reg, value, 0x00);
 122         ret = usb6fire_comm_send_buffer(buffer, rt->chip->dev);
 123
 124         kfree(buffer);
 125         return ret;
 126 }
 127
 128 static int usb6fire_comm_write16(struct comm_runtime *rt, u8 request,
 129                 u8 reg, u8 vl, u8 vh)
 130 {
 131         u8 *buffer;
 132         int ret;
 133
 134         /* 13: maximum length of message */
 135         buffer = kmalloc(13, GFP_KERNEL);
 136         if (!buffer)
 137                 return -ENOMEM;
 138
 139         usb6fire_comm_init_buffer(buffer, 0x00, request, reg, vl, vh);
 140         ret = usb6fire_comm_send_buffer(buffer, rt->chip->dev);
 141
 142         kfree(buffer);
 143         return ret;
 144 }
 145
 146 int usb6fire_comm_init(struct sfire_chip *chip)
 147 {
 148         struct comm_runtime *rt = kzalloc(sizeof(struct comm_runtime),
 149                         GFP_KERNEL);
 150         struct urb *urb;
 151         int ret;
 152
 153         if (!rt)
 154                 return -ENOMEM;
 155
 156         rt->receiver_buffer = kzalloc(COMM_RECEIVER_BUFSIZE, GFP_KERNEL);
 157         if (!rt->receiver_buffer) {
 158                 kfree(rt);
 159                 return -ENOMEM;
 160         }
 161
 162         urb = &rt->receiver;
 163         rt->serial = 1;
 164         rt->chip = chip;
 165         usb_init_urb(urb);
 166         rt->init_urb = usb6fire_comm_init_urb;
 167         rt->write8 = usb6fire_comm_write8;
 168         rt->write16 = usb6fire_comm_write16;
 169
 170         /* submit an urb that receives communication data from device */
 171         urb->transfer_buffer = rt->receiver_buffer;
 172         urb->transfer_buffer_length = COMM_RECEIVER_BUFSIZE;
 173         urb->pipe = usb_rcvintpipe(chip->dev, COMM_EP);
 174         urb->dev = chip->dev;
 175         urb->complete = usb6fire_comm_receiver_handler;
 176         urb->context = rt;
 177         urb->interval = 1;
 178         ret = usb_submit_urb(urb, GFP_KERNEL);
 179         if (ret < 0) {
 180                 kfree(rt->receiver_buffer);
 181                 kfree(rt);
 182                 dev_err(&chip->dev->dev, "cannot create comm data receiver.");
 183                 return ret;
 184         }
 185         chip->comm = rt;
 186         return 0;
 187 }
 188
 189 void usb6fire_comm_abort(struct sfire_chip *chip)
 190 {
 191         struct comm_runtime *rt = chip->comm;
 192
 193         if (rt)
 194                 usb_poison_urb(&rt->receiver);
 195 }
 196
 197 void usb6fire_comm_destroy(struct sfire_chip *chip)
 198 {
 199         struct comm_runtime *rt = chip->comm;
 200
 201         kfree(rt->receiver_buffer);
 202         kfree(rt);
 203         chip->comm = NULL;
 204 }