1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ngene-dvb.c: nGene PCIe bridge driver - DVB functions
4 *
5 * Copyright (C) 2005-2007 Micronas
6 *
7 * Copyright (C) 2008-2009 Ralph Metzler <rjkm@metzlerbros.de>
8 *                         Modifications for new nGene firmware,
9 *                         support for EEPROM-copying,
10 *                         support for new dual DVB-S2 card prototype
11 */
12
13#include <linux/module.h>
14#include <linux/init.h>
15#include <linux/delay.h>
16#include <linux/slab.h>
17#include <linux/poll.h>
18#include <linux/io.h>
19#include <asm/div64.h>
20#include <linux/pci.h>
21#include <linux/timer.h>
22#include <linux/byteorder/generic.h>
23#include <linux/firmware.h>
24#include <linux/vmalloc.h>
25
26#include "ngene.h"
27
28static int ci_tsfix = 1;
29module_param(ci_tsfix, int, 0444);
30MODULE_PARM_DESC(ci_tsfix, "Detect and fix TS buffer offset shifts in conjunction with CI expansions (default: 1/enabled)");
31
32/****************************************************************************/
33/* COMMAND API interface ****************************************************/
34/****************************************************************************/
35
36static ssize_t ts_write(struct file *file, const char __user *buf,
37			size_t count, loff_t *ppos)
38{
39	struct dvb_device *dvbdev = file->private_data;
40	struct ngene_channel *chan = dvbdev->priv;
41	struct ngene *dev = chan->dev;
42
43	if (wait_event_interruptible(dev->tsout_rbuf.queue,
44				     dvb_ringbuffer_free
45				     (&dev->tsout_rbuf) >= count) < 0)
46		return 0;
47
48	dvb_ringbuffer_write_user(&dev->tsout_rbuf, buf, count);
49
50	return count;
51}
52
53static ssize_t ts_read(struct file *file, char __user *buf,
54		       size_t count, loff_t *ppos)
55{
56	struct dvb_device *dvbdev = file->private_data;
57	struct ngene_channel *chan = dvbdev->priv;
58	struct ngene *dev = chan->dev;
59	int left, avail;
60
61	left = count;
62	while (left) {
63		if (wait_event_interruptible(
64			    dev->tsin_rbuf.queue,
65			    dvb_ringbuffer_avail(&dev->tsin_rbuf) > 0) < 0)
66			return -EAGAIN;
67		avail = dvb_ringbuffer_avail(&dev->tsin_rbuf);
68		if (avail > left)
69			avail = left;
70		dvb_ringbuffer_read_user(&dev->tsin_rbuf, buf, avail);
71		left -= avail;
72		buf += avail;
73	}
74	return count;
75}
76
77static __poll_t ts_poll(struct file *file, poll_table *wait)
78{
79	struct dvb_device *dvbdev = file->private_data;
80	struct ngene_channel *chan = dvbdev->priv;
81	struct ngene *dev = chan->dev;
82	struct dvb_ringbuffer *rbuf = &dev->tsin_rbuf;
83	struct dvb_ringbuffer *wbuf = &dev->tsout_rbuf;
84	__poll_t mask = 0;
85
86	poll_wait(file, &rbuf->queue, wait);
87	poll_wait(file, &wbuf->queue, wait);
88
89	if (!dvb_ringbuffer_empty(rbuf))
90		mask |= EPOLLIN | EPOLLRDNORM;
91	if (dvb_ringbuffer_free(wbuf) >= 188)
92		mask |= EPOLLOUT | EPOLLWRNORM;
93
94	return mask;
95}
96
97static const struct file_operations ci_fops = {
98	.owner   = THIS_MODULE,
99	.read    = ts_read,
100	.write   = ts_write,
101	.open    = dvb_generic_open,
102	.release = dvb_generic_release,
103	.poll    = ts_poll,
104	.mmap    = NULL,
105};
106
107struct dvb_device ngene_dvbdev_ci = {
108	.priv    = NULL,
109	.readers = 1,
110	.writers = 1,
111	.users   = 2,
112	.fops    = &ci_fops,
113};
114
115
116/****************************************************************************/
117/* DVB functions and API interface ******************************************/
118/****************************************************************************/
119
120static void swap_buffer(u32 *p, u32 len)
121{
122	while (len) {
123		*p = swab32(*p);
124		p++;
125		len -= 4;
126	}
127}
128
129/* start of filler packet */
130static u8 fill_ts[] = { 0x47, 0x1f, 0xff, 0x10, TS_FILLER };
131
132static int tsin_find_offset(void *buf, u32 len)
133{
134	int i, l;
135
136	l = len - sizeof(fill_ts);
137	if (l <= 0)
138		return -1;
139
140	for (i = 0; i < l; i++) {
141		if (((char *)buf)[i] == 0x47) {
142			if (!memcmp(buf + i, fill_ts, sizeof(fill_ts)))
143				return i % 188;
144		}
145	}
146
147	return -1;
148}
149
150static inline void tsin_copy_stripped(struct ngene *dev, void *buf)
151{
152	if (memcmp(buf, fill_ts, sizeof(fill_ts)) != 0) {
153		if (dvb_ringbuffer_free(&dev->tsin_rbuf) >= 188) {
154			dvb_ringbuffer_write(&dev->tsin_rbuf, buf, 188);
155			wake_up(&dev->tsin_rbuf.queue);
156		}
157	}
158}
159
160void *tsin_exchange(void *priv, void *buf, u32 len, u32 clock, u32 flags)
161{
162	struct ngene_channel *chan = priv;
163	struct ngene *dev = chan->dev;
164	int tsoff;
165
166	if (flags & DF_SWAP32)
167		swap_buffer(buf, len);
168
169	if (dev->ci.en && chan->number == 2) {
170		/* blindly copy buffers if ci_tsfix is disabled */
171		if (!ci_tsfix) {
172			while (len >= 188) {
173				tsin_copy_stripped(dev, buf);
174
175				buf += 188;
176				len -= 188;
177			}
178			return NULL;
179		}
180
181		/* ci_tsfix = 1 */
182
183		/*
184		 * since the remainder of the TS packet which got cut off
185		 * in the previous tsin_exchange() run is at the beginning
186		 * of the new TS buffer, append this to the temp buffer and
187		 * send it to the DVB ringbuffer afterwards.
188		 */
189		if (chan->tsin_offset) {
190			memcpy(&chan->tsin_buffer[(188 - chan->tsin_offset)],
191			       buf, chan->tsin_offset);
192			tsin_copy_stripped(dev, &chan->tsin_buffer);
193
194			buf += chan->tsin_offset;
195			len -= chan->tsin_offset;
196		}
197
198		/*
199		 * copy TS packets to the DVB ringbuffer and detect new offset
200		 * shifts by checking for a valid TS SYNC byte
201		 */
202		while (len >= 188) {
203			if (*((char *)buf) != 0x47) {
204				/*
205				 * no SYNC header, find new offset shift
206				 * (max. 188 bytes, tsoff will be mod 188)
207				 */
208				tsoff = tsin_find_offset(buf, len);
209				if (tsoff > 0) {
210					chan->tsin_offset += tsoff;
211					chan->tsin_offset %= 188;
212
213					buf += tsoff;
214					len -= tsoff;
215
216					dev_info(&dev->pci_dev->dev,
217						 "%s(): tsin_offset shift by %d on channel %d\n",
218						 __func__, tsoff,
219						 chan->number);
220
221					/*
222					 * offset corrected. re-check remaining
223					 * len for a full TS frame, break and
224					 * skip to fragment handling if < 188.
225					 */
226					if (len < 188)
227						break;
228				}
229			}
230
231			tsin_copy_stripped(dev, buf);
232
233			buf += 188;
234			len -= 188;
235		}
236
237		/*
238		 * if a fragment is left, copy to temp buffer. The remainder
239		 * will be appended in the next tsin_exchange() iteration.
240		 */
241		if (len > 0 && len < 188)
242			memcpy(&chan->tsin_buffer, buf, len);
243
244		return NULL;
245	}
246
247	if (chan->users > 0)
248		dvb_dmx_swfilter(&chan->demux, buf, len);
249
250	return NULL;
251}
252
253void *tsout_exchange(void *priv, void *buf, u32 len, u32 clock, u32 flags)
254{
255	struct ngene_channel *chan = priv;
256	struct ngene *dev = chan->dev;
257	u32 alen;
258
259	alen = dvb_ringbuffer_avail(&dev->tsout_rbuf);
260	alen -= alen % 188;
261
262	if (alen < len)
263		FillTSBuffer(buf + alen, len - alen, flags);
264	else
265		alen = len;
266	dvb_ringbuffer_read(&dev->tsout_rbuf, buf, alen);
267	if (flags & DF_SWAP32)
268		swap_buffer((u32 *)buf, alen);
269	wake_up_interruptible(&dev->tsout_rbuf.queue);
270	return buf;
271}
272
273
274
275int ngene_start_feed(struct dvb_demux_feed *dvbdmxfeed)
276{
277	struct dvb_demux *dvbdmx = dvbdmxfeed->demux;
278	struct ngene_channel *chan = dvbdmx->priv;
279
280	if (chan->users == 0) {
281		if (!chan->dev->cmd_timeout_workaround || !chan->running)
282			set_transfer(chan, 1);
283	}
284
285	return ++chan->users;
286}
287
288int ngene_stop_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)
294		return chan->users;
295
296	if (!chan->dev->cmd_timeout_workaround)
297		set_transfer(chan, 0);
298
299	return 0;
300}
301
302int my_dvb_dmx_ts_card_init(struct dvb_demux *dvbdemux, char *id,
303			    int (*start_feed)(struct dvb_demux_feed *),
304			    int (*stop_feed)(struct dvb_demux_feed *),
305			    void *priv)
306{
307	dvbdemux->priv = priv;
308
309	dvbdemux->filternum = 256;
310	dvbdemux->feednum = 256;
311	dvbdemux->start_feed = start_feed;
312	dvbdemux->stop_feed = stop_feed;
313	dvbdemux->write_to_decoder = NULL;
314	dvbdemux->dmx.capabilities = (DMX_TS_FILTERING |
315				      DMX_SECTION_FILTERING |
316				      DMX_MEMORY_BASED_FILTERING);
317	return dvb_dmx_init(dvbdemux);
318}
319
320int my_dvb_dmxdev_ts_card_init(struct dmxdev *dmxdev,
321			       struct dvb_demux *dvbdemux,
322			       struct dmx_frontend *hw_frontend,
323			       struct dmx_frontend *mem_frontend,
324			       struct dvb_adapter *dvb_adapter)
325{
326	int ret;
327
328	dmxdev->filternum = 256;
329	dmxdev->demux = &dvbdemux->dmx;
330	dmxdev->capabilities = 0;
331	ret = dvb_dmxdev_init(dmxdev, dvb_adapter);
332	if (ret < 0)
333		return ret;
334
335	hw_frontend->source = DMX_FRONTEND_0;
336	dvbdemux->dmx.add_frontend(&dvbdemux->dmx, hw_frontend);
337	mem_frontend->source = DMX_MEMORY_FE;
338	dvbdemux->dmx.add_frontend(&dvbdemux->dmx, mem_frontend);
339	return dvbdemux->dmx.connect_frontend(&dvbdemux->dmx, hw_frontend);
340}
341