1 /*
2  * ngene-dvb.c: nGene PCIe bridge driver - DVB functions
3  *
4  * Copyright (C) 2005-2007 Micronas
5  *
6  * Copyright (C) 2008-2009 Ralph Metzler <rjkm@metzlerbros.de>
7  *                         Modifications for new nGene firmware,
8  *                         support for EEPROM-copying,
9  *                         support for new dual DVB-S2 card prototype
10  *
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License
14  * version 2 only, as published by the Free Software Foundation.
15  *
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * To obtain the license, point your browser to
23  * http://www.gnu.org/copyleft/gpl.html
24  */
25 
26 #include <linux/module.h>
27 #include <linux/init.h>
28 #include <linux/delay.h>
29 #include <linux/slab.h>
30 #include <linux/poll.h>
31 #include <linux/io.h>
32 #include <asm/div64.h>
33 #include <linux/pci.h>
34 #include <linux/timer.h>
35 #include <linux/byteorder/generic.h>
36 #include <linux/firmware.h>
37 #include <linux/vmalloc.h>
38 
39 #include "ngene.h"
40 
41 static int ci_tsfix = 1;
42 module_param(ci_tsfix, int, 0444);
43 MODULE_PARM_DESC(ci_tsfix, "Detect and fix TS buffer offset shifts in conjunction with CI expansions (default: 1/enabled)");
44 
45 /****************************************************************************/
46 /* COMMAND API interface ****************************************************/
47 /****************************************************************************/
48 
49 static ssize_t ts_write(struct file *file, const char __user *buf,
50 			size_t count, loff_t *ppos)
51 {
52 	struct dvb_device *dvbdev = file->private_data;
53 	struct ngene_channel *chan = dvbdev->priv;
54 	struct ngene *dev = chan->dev;
55 
56 	if (wait_event_interruptible(dev->tsout_rbuf.queue,
57 				     dvb_ringbuffer_free
58 				     (&dev->tsout_rbuf) >= count) < 0)
59 		return 0;
60 
61 	dvb_ringbuffer_write_user(&dev->tsout_rbuf, buf, count);
62 
63 	return count;
64 }
65 
66 static ssize_t ts_read(struct file *file, char __user *buf,
67 		       size_t count, loff_t *ppos)
68 {
69 	struct dvb_device *dvbdev = file->private_data;
70 	struct ngene_channel *chan = dvbdev->priv;
71 	struct ngene *dev = chan->dev;
72 	int left, avail;
73 
74 	left = count;
75 	while (left) {
76 		if (wait_event_interruptible(
77 			    dev->tsin_rbuf.queue,
78 			    dvb_ringbuffer_avail(&dev->tsin_rbuf) > 0) < 0)
79 			return -EAGAIN;
80 		avail = dvb_ringbuffer_avail(&dev->tsin_rbuf);
81 		if (avail > left)
82 			avail = left;
83 		dvb_ringbuffer_read_user(&dev->tsin_rbuf, buf, avail);
84 		left -= avail;
85 		buf += avail;
86 	}
87 	return count;
88 }
89 
90 static __poll_t ts_poll(struct file *file, poll_table *wait)
91 {
92 	struct dvb_device *dvbdev = file->private_data;
93 	struct ngene_channel *chan = dvbdev->priv;
94 	struct ngene *dev = chan->dev;
95 	struct dvb_ringbuffer *rbuf = &dev->tsin_rbuf;
96 	struct dvb_ringbuffer *wbuf = &dev->tsout_rbuf;
97 	__poll_t mask = 0;
98 
99 	poll_wait(file, &rbuf->queue, wait);
100 	poll_wait(file, &wbuf->queue, wait);
101 
102 	if (!dvb_ringbuffer_empty(rbuf))
103 		mask |= EPOLLIN | EPOLLRDNORM;
104 	if (dvb_ringbuffer_free(wbuf) >= 188)
105 		mask |= EPOLLOUT | EPOLLWRNORM;
106 
107 	return mask;
108 }
109 
110 static const struct file_operations ci_fops = {
111 	.owner   = THIS_MODULE,
112 	.read    = ts_read,
113 	.write   = ts_write,
114 	.open    = dvb_generic_open,
115 	.release = dvb_generic_release,
116 	.poll    = ts_poll,
117 	.mmap    = NULL,
118 };
119 
120 struct dvb_device ngene_dvbdev_ci = {
121 	.priv    = NULL,
122 	.readers = 1,
123 	.writers = 1,
124 	.users   = 2,
125 	.fops    = &ci_fops,
126 };
127 
128 
129 /****************************************************************************/
130 /* DVB functions and API interface ******************************************/
131 /****************************************************************************/
132 
133 static void swap_buffer(u32 *p, u32 len)
134 {
135 	while (len) {
136 		*p = swab32(*p);
137 		p++;
138 		len -= 4;
139 	}
140 }
141 
142 /* start of filler packet */
143 static u8 fill_ts[] = { 0x47, 0x1f, 0xff, 0x10, TS_FILLER };
144 
145 static int tsin_find_offset(void *buf, u32 len)
146 {
147 	int i, l;
148 
149 	l = len - sizeof(fill_ts);
150 	if (l <= 0)
151 		return -1;
152 
153 	for (i = 0; i < l; i++) {
154 		if (((char *)buf)[i] == 0x47) {
155 			if (!memcmp(buf + i, fill_ts, sizeof(fill_ts)))
156 				return i % 188;
157 		}
158 	}
159 
160 	return -1;
161 }
162 
163 static inline void tsin_copy_stripped(struct ngene *dev, void *buf)
164 {
165 	if (memcmp(buf, fill_ts, sizeof(fill_ts)) != 0) {
166 		if (dvb_ringbuffer_free(&dev->tsin_rbuf) >= 188) {
167 			dvb_ringbuffer_write(&dev->tsin_rbuf, buf, 188);
168 			wake_up(&dev->tsin_rbuf.queue);
169 		}
170 	}
171 }
172 
173 void *tsin_exchange(void *priv, void *buf, u32 len, u32 clock, u32 flags)
174 {
175 	struct ngene_channel *chan = priv;
176 	struct ngene *dev = chan->dev;
177 	int tsoff;
178 
179 	if (flags & DF_SWAP32)
180 		swap_buffer(buf, len);
181 
182 	if (dev->ci.en && chan->number == 2) {
183 		/* blindly copy buffers if ci_tsfix is disabled */
184 		if (!ci_tsfix) {
185 			while (len >= 188) {
186 				tsin_copy_stripped(dev, buf);
187 
188 				buf += 188;
189 				len -= 188;
190 			}
191 			return NULL;
192 		}
193 
194 		/* ci_tsfix = 1 */
195 
196 		/*
197 		 * since the remainder of the TS packet which got cut off
198 		 * in the previous tsin_exchange() run is at the beginning
199 		 * of the new TS buffer, append this to the temp buffer and
200 		 * send it to the DVB ringbuffer afterwards.
201 		 */
202 		if (chan->tsin_offset) {
203 			memcpy(&chan->tsin_buffer[(188 - chan->tsin_offset)],
204 			       buf, chan->tsin_offset);
205 			tsin_copy_stripped(dev, &chan->tsin_buffer);
206 
207 			buf += chan->tsin_offset;
208 			len -= chan->tsin_offset;
209 		}
210 
211 		/*
212 		 * copy TS packets to the DVB ringbuffer and detect new offset
213 		 * shifts by checking for a valid TS SYNC byte
214 		 */
215 		while (len >= 188) {
216 			if (*((char *)buf) != 0x47) {
217 				/*
218 				 * no SYNC header, find new offset shift
219 				 * (max. 188 bytes, tsoff will be mod 188)
220 				 */
221 				tsoff = tsin_find_offset(buf, len);
222 				if (tsoff > 0) {
223 					chan->tsin_offset += tsoff;
224 					chan->tsin_offset %= 188;
225 
226 					buf += tsoff;
227 					len -= tsoff;
228 
229 					dev_info(&dev->pci_dev->dev,
230 						 "%s(): tsin_offset shift by %d on channel %d\n",
231 						 __func__, tsoff,
232 						 chan->number);
233 
234 					/*
235 					 * offset corrected. re-check remaining
236 					 * len for a full TS frame, break and
237 					 * skip to fragment handling if < 188.
238 					 */
239 					if (len < 188)
240 						break;
241 				}
242 			}
243 
244 			tsin_copy_stripped(dev, buf);
245 
246 			buf += 188;
247 			len -= 188;
248 		}
249 
250 		/*
251 		 * if a fragment is left, copy to temp buffer. The remainder
252 		 * will be appended in the next tsin_exchange() iteration.
253 		 */
254 		if (len > 0 && len < 188)
255 			memcpy(&chan->tsin_buffer, buf, len);
256 
257 		return NULL;
258 	}
259 
260 	if (chan->users > 0)
261 		dvb_dmx_swfilter(&chan->demux, buf, len);
262 
263 	return NULL;
264 }
265 
266 void *tsout_exchange(void *priv, void *buf, u32 len, u32 clock, u32 flags)
267 {
268 	struct ngene_channel *chan = priv;
269 	struct ngene *dev = chan->dev;
270 	u32 alen;
271 
272 	alen = dvb_ringbuffer_avail(&dev->tsout_rbuf);
273 	alen -= alen % 188;
274 
275 	if (alen < len)
276 		FillTSBuffer(buf + alen, len - alen, flags);
277 	else
278 		alen = len;
279 	dvb_ringbuffer_read(&dev->tsout_rbuf, buf, alen);
280 	if (flags & DF_SWAP32)
281 		swap_buffer((u32 *)buf, alen);
282 	wake_up_interruptible(&dev->tsout_rbuf.queue);
283 	return buf;
284 }
285 
286 
287 
288 int ngene_start_feed(struct dvb_demux_feed *dvbdmxfeed)
289 {
290 	struct dvb_demux *dvbdmx = dvbdmxfeed->demux;
291 	struct ngene_channel *chan = dvbdmx->priv;
292 
293 	if (chan->users == 0) {
294 		if (!chan->dev->cmd_timeout_workaround || !chan->running)
295 			set_transfer(chan, 1);
296 	}
297 
298 	return ++chan->users;
299 }
300 
301 int ngene_stop_feed(struct dvb_demux_feed *dvbdmxfeed)
302 {
303 	struct dvb_demux *dvbdmx = dvbdmxfeed->demux;
304 	struct ngene_channel *chan = dvbdmx->priv;
305 
306 	if (--chan->users)
307 		return chan->users;
308 
309 	if (!chan->dev->cmd_timeout_workaround)
310 		set_transfer(chan, 0);
311 
312 	return 0;
313 }
314 
315 int my_dvb_dmx_ts_card_init(struct dvb_demux *dvbdemux, char *id,
316 			    int (*start_feed)(struct dvb_demux_feed *),
317 			    int (*stop_feed)(struct dvb_demux_feed *),
318 			    void *priv)
319 {
320 	dvbdemux->priv = priv;
321 
322 	dvbdemux->filternum = 256;
323 	dvbdemux->feednum = 256;
324 	dvbdemux->start_feed = start_feed;
325 	dvbdemux->stop_feed = stop_feed;
326 	dvbdemux->write_to_decoder = NULL;
327 	dvbdemux->dmx.capabilities = (DMX_TS_FILTERING |
328 				      DMX_SECTION_FILTERING |
329 				      DMX_MEMORY_BASED_FILTERING);
330 	return dvb_dmx_init(dvbdemux);
331 }
332 
333 int my_dvb_dmxdev_ts_card_init(struct dmxdev *dmxdev,
334 			       struct dvb_demux *dvbdemux,
335 			       struct dmx_frontend *hw_frontend,
336 			       struct dmx_frontend *mem_frontend,
337 			       struct dvb_adapter *dvb_adapter)
338 {
339 	int ret;
340 
341 	dmxdev->filternum = 256;
342 	dmxdev->demux = &dvbdemux->dmx;
343 	dmxdev->capabilities = 0;
344 	ret = dvb_dmxdev_init(dmxdev, dvb_adapter);
345 	if (ret < 0)
346 		return ret;
347 
348 	hw_frontend->source = DMX_FRONTEND_0;
349 	dvbdemux->dmx.add_frontend(&dvbdemux->dmx, hw_frontend);
350 	mem_frontend->source = DMX_MEMORY_FE;
351 	dvbdemux->dmx.add_frontend(&dvbdemux->dmx, mem_frontend);
352 	return dvbdemux->dmx.connect_frontend(&dvbdemux->dmx, hw_frontend);
353 }
354