IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
[linux-2.6.git] / drivers / isdn / hisax / st5481_b.c
1 /*
2  * Driver for ST5481 USB ISDN modem
3  *
4  * Author       Frode Isaksen
5  * Copyright    2001 by Frode Isaksen      <fisaksen@bewan.com>
6  *              2001 by Kai Germaschewski  <kai.germaschewski@gmx.de>
7  * 
8  * This software may be used and distributed according to the terms
9  * of the GNU General Public License, incorporated herein by reference.
10  *
11  */
12
13 #include <linux/init.h>
14 #include <linux/usb.h>
15 #include <linux/slab.h>
16 #include <linux/netdevice.h>
17 #include "st5481.h"
18
19 static inline void B_L1L2(struct st5481_bcs *bcs, int pr, void *arg)
20 {
21         struct hisax_if *ifc = (struct hisax_if *) &bcs->b_if;
22
23         ifc->l1l2(ifc, pr, arg);
24 }
25
26 /*
27  * Encode and transmit next frame.
28  */
29 static void usb_b_out(struct st5481_bcs *bcs,int buf_nr)
30 {
31         struct st5481_b_out *b_out = &bcs->b_out;
32         struct st5481_adapter *adapter = bcs->adapter;
33         struct urb *urb;
34         unsigned int packet_size,offset;
35         int len,buf_size,bytes_sent;
36         int i;
37         struct sk_buff *skb;
38         
39         if (test_and_set_bit(buf_nr, &b_out->busy)) {
40                 DBG(4,"ep %d urb %d busy",(bcs->channel+1)*2,buf_nr);
41                 return;
42         }
43         urb = b_out->urb[buf_nr];
44
45         // Adjust isoc buffer size according to flow state
46         if(b_out->flow_event & (OUT_DOWN | OUT_UNDERRUN)) {
47                 buf_size = NUM_ISO_PACKETS_B*SIZE_ISO_PACKETS_B_OUT + B_FLOW_ADJUST;
48                 packet_size = SIZE_ISO_PACKETS_B_OUT + B_FLOW_ADJUST;
49                 DBG(4,"B%d,adjust flow,add %d bytes",bcs->channel+1,B_FLOW_ADJUST);
50         } else if(b_out->flow_event & OUT_UP){
51                 buf_size = NUM_ISO_PACKETS_B*SIZE_ISO_PACKETS_B_OUT - B_FLOW_ADJUST;
52                 packet_size = SIZE_ISO_PACKETS_B_OUT - B_FLOW_ADJUST;
53                 DBG(4,"B%d,adjust flow,remove %d bytes",bcs->channel+1,B_FLOW_ADJUST);
54         } else {
55                 buf_size = NUM_ISO_PACKETS_B*SIZE_ISO_PACKETS_B_OUT;
56                 packet_size = 8;
57         }
58         b_out->flow_event = 0;
59
60         len = 0;
61         while (len < buf_size) {
62                 if ((skb = b_out->tx_skb)) {
63                         DBG_SKB(0x100, skb);
64                         DBG(4,"B%d,len=%d",bcs->channel+1,skb->len);
65                         
66                         if (bcs->mode == L1_MODE_TRANS) {       
67                                 bytes_sent = buf_size - len;
68                                 if (skb->len < bytes_sent)
69                                         bytes_sent = skb->len;
70                                 {       /* swap tx bytes to get hearable audio data */
71                                         register unsigned char *src  = skb->data;
72                                         register unsigned char *dest = urb->transfer_buffer+len;
73                                         register unsigned int count;
74                                         for (count = 0; count < bytes_sent; count++)
75                                                 *dest++ = isdnhdlc_bit_rev_tab[*src++];
76                                 }
77                                 len += bytes_sent;
78                         } else {
79                                 len += isdnhdlc_encode(&b_out->hdlc_state,
80                                                        skb->data, skb->len, &bytes_sent,
81                                                        urb->transfer_buffer+len, buf_size-len);
82                         }
83
84                         skb_pull(skb, bytes_sent);
85
86                         if (!skb->len) {
87                                 // Frame sent
88                                 b_out->tx_skb = NULL;
89                                 B_L1L2(bcs, PH_DATA | CONFIRM, (void *)(unsigned long) skb->truesize);
90                                 dev_kfree_skb_any(skb);
91
92 /*                              if (!(bcs->tx_skb = skb_dequeue(&bcs->sq))) { */
93 /*                                      st5481B_sched_event(bcs, B_XMTBUFREADY); */
94 /*                              } */
95                         }
96                 } else {
97                         if (bcs->mode == L1_MODE_TRANS) {
98                                 memset(urb->transfer_buffer+len, 0xff, buf_size-len);
99                                 len = buf_size;
100                         } else {
101                                 // Send flags
102                                 len += isdnhdlc_encode(&b_out->hdlc_state,
103                                                        NULL, 0, &bytes_sent,
104                                                        urb->transfer_buffer+len, buf_size-len);
105                         }
106                 }       
107         }
108
109         // Prepare the URB
110         for (i = 0, offset = 0; offset < len; i++) {
111                 urb->iso_frame_desc[i].offset = offset;
112                 urb->iso_frame_desc[i].length = packet_size;
113                 offset += packet_size;
114                 packet_size = SIZE_ISO_PACKETS_B_OUT;
115         }
116         urb->transfer_buffer_length = len;
117         urb->number_of_packets = i;
118         urb->dev = adapter->usb_dev;
119
120         DBG_ISO_PACKET(0x200,urb);
121
122         SUBMIT_URB(urb, GFP_NOIO);
123 }
124
125 /*
126  * Start transfering (flags or data) on the B channel, since
127  * FIFO counters has been set to a non-zero value.
128  */
129 static void st5481B_start_xfer(void *context)
130 {
131         struct st5481_bcs *bcs = context;
132
133         DBG(4,"B%d",bcs->channel+1);
134
135         // Start transmitting (flags or data) on B channel
136
137         usb_b_out(bcs,0);
138         usb_b_out(bcs,1);
139 }
140
141 /*
142  * If the adapter has only 2 LEDs, the green
143  * LED will blink with a rate depending
144  * on the number of channels opened.
145  */
146 static void led_blink(struct st5481_adapter *adapter)
147 {
148         u_char leds = adapter->leds;
149
150         // 50 frames/sec for each channel
151         if (++adapter->led_counter % 50) {
152                 return;
153         }
154
155         if (adapter->led_counter % 100) {
156                 leds |= GREEN_LED;
157         } else {
158                 leds &= ~GREEN_LED;
159         }
160         
161         st5481_usb_device_ctrl_msg(adapter, GPIO_OUT, leds, NULL, NULL);
162 }
163
164 static void usb_b_out_complete(struct urb *urb)
165 {
166         struct st5481_bcs *bcs = urb->context;
167         struct st5481_b_out *b_out = &bcs->b_out;
168         struct st5481_adapter *adapter = bcs->adapter;
169         int buf_nr;
170         
171         buf_nr = get_buf_nr(b_out->urb, urb);
172         test_and_clear_bit(buf_nr, &b_out->busy);
173
174         if (unlikely(urb->status < 0)) {
175                 switch (urb->status) {
176                         case -ENOENT:
177                         case -ESHUTDOWN:
178                         case -ECONNRESET:
179                                 DBG(4,"urb killed status %d", urb->status);
180                                 return; // Give up
181                         default: 
182                                 WARN("urb status %d",urb->status);
183                                 if (b_out->busy == 0) {
184                                         st5481_usb_pipe_reset(adapter, (bcs->channel+1)*2 | USB_DIR_OUT, NULL, NULL);
185                                 }
186                                 break;
187                 }
188         }
189
190         usb_b_out(bcs,buf_nr);
191
192         if (adapter->number_of_leds == 2)
193                 led_blink(adapter);
194 }
195
196 /*
197  * Start or stop the transfer on the B channel.
198  */
199 static void st5481B_mode(struct st5481_bcs *bcs, int mode)
200 {
201         struct st5481_b_out *b_out = &bcs->b_out;
202         struct st5481_adapter *adapter = bcs->adapter;
203
204         DBG(4,"B%d,mode=%d", bcs->channel + 1, mode);
205
206         if (bcs->mode == mode)
207                 return;
208
209         bcs->mode = mode;
210
211         // Cancel all USB transfers on this B channel
212         usb_unlink_urb(b_out->urb[0]);
213         usb_unlink_urb(b_out->urb[1]);
214         b_out->busy = 0;
215
216         st5481_in_mode(&bcs->b_in, mode);
217         if (bcs->mode != L1_MODE_NULL) {
218                 // Open the B channel
219                 if (bcs->mode != L1_MODE_TRANS) {
220                         isdnhdlc_out_init(&b_out->hdlc_state, 0, bcs->mode == L1_MODE_HDLC_56K);
221                 }
222                 st5481_usb_pipe_reset(adapter, (bcs->channel+1)*2, NULL, NULL);
223         
224                 // Enable B channel interrupts
225                 st5481_usb_device_ctrl_msg(adapter, FFMSK_B1+(bcs->channel*2), 
226                                     OUT_UP+OUT_DOWN+OUT_UNDERRUN, NULL, NULL);
227
228                 // Enable B channel FIFOs
229                 st5481_usb_device_ctrl_msg(adapter, OUT_B1_COUNTER+(bcs->channel*2), 32, st5481B_start_xfer, bcs);
230                 if (adapter->number_of_leds == 4) {
231                         if (bcs->channel == 0) {
232                                 adapter->leds |= B1_LED;
233                         } else {
234                                 adapter->leds |= B2_LED;
235                         }
236                 }
237         } else {
238                 // Disble B channel interrupts
239                 st5481_usb_device_ctrl_msg(adapter, FFMSK_B1+(bcs->channel*2), 0, NULL, NULL);
240
241                 // Disable B channel FIFOs
242                 st5481_usb_device_ctrl_msg(adapter, OUT_B1_COUNTER+(bcs->channel*2), 0, NULL, NULL);
243
244                 if (adapter->number_of_leds == 4) {
245                         if (bcs->channel == 0) {
246                                 adapter->leds &= ~B1_LED;
247                         } else {
248                                 adapter->leds &= ~B2_LED;
249                         }
250                 } else {
251                         st5481_usb_device_ctrl_msg(adapter, GPIO_OUT, adapter->leds, NULL, NULL);
252                 }
253                 if (b_out->tx_skb) {
254                         dev_kfree_skb_any(b_out->tx_skb);
255                         b_out->tx_skb = NULL;
256                 }
257                 
258         }
259 }
260
261 static int st5481_setup_b_out(struct st5481_bcs *bcs)
262 {
263         struct usb_device *dev = bcs->adapter->usb_dev;
264         struct usb_interface *intf;
265         struct usb_host_interface *altsetting = NULL;
266         struct usb_host_endpoint *endpoint;
267         struct st5481_b_out *b_out = &bcs->b_out;
268
269         DBG(4,"");
270
271         intf = usb_ifnum_to_if(dev, 0);
272         if (intf)
273                 altsetting = usb_altnum_to_altsetting(intf, 3);
274         if (!altsetting)
275                 return -ENXIO;
276
277         // Allocate URBs and buffers for the B channel out
278         endpoint = &altsetting->endpoint[EP_B1_OUT - 1 + bcs->channel * 2];
279
280         DBG(4,"endpoint address=%02x,packet size=%d",
281             endpoint->desc.bEndpointAddress, le16_to_cpu(endpoint->desc.wMaxPacketSize));
282
283         // Allocate memory for 8000bytes/sec + extra bytes if underrun
284         return st5481_setup_isocpipes(b_out->urb, dev, 
285                                       usb_sndisocpipe(dev, endpoint->desc.bEndpointAddress),
286                                       NUM_ISO_PACKETS_B, SIZE_ISO_PACKETS_B_OUT,
287                                       NUM_ISO_PACKETS_B * SIZE_ISO_PACKETS_B_OUT + B_FLOW_ADJUST,
288                                       usb_b_out_complete, bcs);
289 }
290
291 static void st5481_release_b_out(struct st5481_bcs *bcs)
292 {
293         struct st5481_b_out *b_out = &bcs->b_out;
294
295         DBG(4,"");
296
297         st5481_release_isocpipes(b_out->urb);
298 }
299
300 int st5481_setup_b(struct st5481_bcs *bcs)
301 {
302         int retval;
303
304         DBG(4,"");
305
306         retval = st5481_setup_b_out(bcs);
307         if (retval)
308                 goto err;
309         bcs->b_in.bufsize = HSCX_BUFMAX;
310         bcs->b_in.num_packets = NUM_ISO_PACKETS_B;
311         bcs->b_in.packet_size = SIZE_ISO_PACKETS_B_IN;
312         bcs->b_in.ep = (bcs->channel ? EP_B2_IN : EP_B1_IN) | USB_DIR_IN;
313         bcs->b_in.counter = bcs->channel ? IN_B2_COUNTER : IN_B1_COUNTER;
314         bcs->b_in.adapter = bcs->adapter;
315         bcs->b_in.hisax_if = &bcs->b_if.ifc;
316         retval = st5481_setup_in(&bcs->b_in);
317         if (retval)
318                 goto err_b_out;
319
320
321         return 0;
322
323  err_b_out:
324         st5481_release_b_out(bcs);
325  err:
326         return retval;
327 }
328
329 /*
330  * Release buffers and URBs for the B channels
331  */
332 void st5481_release_b(struct st5481_bcs *bcs)
333 {
334         DBG(4,"");
335
336         st5481_release_in(&bcs->b_in);
337         st5481_release_b_out(bcs);
338 }
339
340 /*
341  * st5481_b_l2l1 is the entry point for upper layer routines that want to
342  * transmit on the B channel.  PH_DATA | REQUEST is a normal packet that
343  * we either start transmitting (if idle) or queue (if busy).
344  * PH_PULL | REQUEST can be called to request a callback message
345  * (PH_PULL | CONFIRM)
346  * once the link is idle.  After a "pull" callback, the upper layer
347  * routines can use PH_PULL | INDICATION to send data.
348  */
349 void st5481_b_l2l1(struct hisax_if *ifc, int pr, void *arg)
350 {
351         struct st5481_bcs *bcs = ifc->priv;
352         struct sk_buff *skb = arg;
353         long mode;
354
355         DBG(4, "");
356
357         switch (pr) {
358         case PH_DATA | REQUEST:
359                 BUG_ON(bcs->b_out.tx_skb);
360                 bcs->b_out.tx_skb = skb;
361                 break;
362         case PH_ACTIVATE | REQUEST:
363                 mode = (long) arg;
364                 DBG(4,"B%d,PH_ACTIVATE_REQUEST %ld", bcs->channel + 1, mode);
365                 st5481B_mode(bcs, mode);
366                 B_L1L2(bcs, PH_ACTIVATE | INDICATION, NULL);
367                 break;
368         case PH_DEACTIVATE | REQUEST:
369                 DBG(4,"B%d,PH_DEACTIVATE_REQUEST", bcs->channel + 1);
370                 st5481B_mode(bcs, L1_MODE_NULL);
371                 B_L1L2(bcs, PH_DEACTIVATE | INDICATION, NULL);
372                 break;
373         default:
374                 WARN("pr %#x\n", pr);
375         }
376 }