1/*
2 * SQ905 subdriver
3 *
4 * Copyright (C) 2008, 2009 Adam Baker and Theodore Kilgore
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21/*
22 * History and Acknowledgments
23 *
24 * The original Linux driver for SQ905 based cameras was written by
25 * Marcell Lengyel and furter developed by many other contributors
26 * and is available from http://sourceforge.net/projects/sqcam/
27 *
28 * This driver takes advantage of the reverse engineering work done for
29 * that driver and for libgphoto2 but shares no code with them.
30 *
31 * This driver has used as a base the finepix driver and other gspca
32 * based drivers and may still contain code fragments taken from those
33 * drivers.
34 */
35
36#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
37
38#define MODULE_NAME "sq905"
39
40#include <linux/workqueue.h>
41#include <linux/slab.h>
42#include "gspca.h"
43
44MODULE_AUTHOR("Adam Baker <linux@baker-net.org.uk>, "
45		"Theodore Kilgore <kilgota@auburn.edu>");
46MODULE_DESCRIPTION("GSPCA/SQ905 USB Camera Driver");
47MODULE_LICENSE("GPL");
48
49/* Default timeouts, in ms */
50#define SQ905_CMD_TIMEOUT 500
51#define SQ905_DATA_TIMEOUT 1000
52
53/* Maximum transfer size to use. */
54#define SQ905_MAX_TRANSFER 0x8000
55#define FRAME_HEADER_LEN 64
56
57/* The known modes, or registers. These go in the "value" slot. */
58
59/* 00 is "none" obviously */
60
61#define SQ905_BULK_READ	0x03	/* precedes any bulk read */
62#define SQ905_COMMAND	0x06	/* precedes the command codes below */
63#define SQ905_PING	0x07	/* when reading an "idling" command */
64#define SQ905_READ_DONE 0xc0    /* ack bulk read completed */
65
66/* Any non-zero value in the bottom 2 bits of the 2nd byte of
67 * the ID appears to indicate the camera can do 640*480. If the
68 * LSB of that byte is set the image is just upside down, otherwise
69 * it is rotated 180 degrees. */
70#define SQ905_HIRES_MASK	0x00000300
71#define SQ905_ORIENTATION_MASK	0x00000100
72
73/* Some command codes. These go in the "index" slot. */
74
75#define SQ905_ID      0xf0	/* asks for model string */
76#define SQ905_CONFIG  0x20	/* gets photo alloc. table, not used here */
77#define SQ905_DATA    0x30	/* accesses photo data, not used here */
78#define SQ905_CLEAR   0xa0	/* clear everything */
79#define SQ905_CAPTURE_LOW  0x60	/* Starts capture at 160x120 */
80#define SQ905_CAPTURE_MED  0x61	/* Starts capture at 320x240 */
81#define SQ905_CAPTURE_HIGH 0x62	/* Starts capture at 640x480 (some cams only) */
82/* note that the capture command also controls the output dimensions */
83
84/* Structure to hold all of our device specific stuff */
85struct sd {
86	struct gspca_dev gspca_dev;	/* !! must be the first item */
87
88	/*
89	 * Driver stuff
90	 */
91	struct work_struct work_struct;
92	struct workqueue_struct *work_thread;
93};
94
95static struct v4l2_pix_format sq905_mode[] = {
96	{ 160, 120, V4L2_PIX_FMT_SBGGR8, V4L2_FIELD_NONE,
97		.bytesperline = 160,
98		.sizeimage = 160 * 120,
99		.colorspace = V4L2_COLORSPACE_SRGB,
100		.priv = 0},
101	{ 320, 240, V4L2_PIX_FMT_SBGGR8, V4L2_FIELD_NONE,
102		.bytesperline = 320,
103		.sizeimage = 320 * 240,
104		.colorspace = V4L2_COLORSPACE_SRGB,
105		.priv = 0},
106	{ 640, 480, V4L2_PIX_FMT_SBGGR8, V4L2_FIELD_NONE,
107		.bytesperline = 640,
108		.sizeimage = 640 * 480,
109		.colorspace = V4L2_COLORSPACE_SRGB,
110		.priv = 0}
111};
112
113/*
114 * Send a command to the camera.
115 */
116static int sq905_command(struct gspca_dev *gspca_dev, u16 index)
117{
118	int ret;
119
120	gspca_dev->usb_buf[0] = '\0';
121	ret = usb_control_msg(gspca_dev->dev,
122			      usb_sndctrlpipe(gspca_dev->dev, 0),
123			      USB_REQ_SYNCH_FRAME,                /* request */
124			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
125			      SQ905_COMMAND, index, gspca_dev->usb_buf, 1,
126			      SQ905_CMD_TIMEOUT);
127	if (ret < 0) {
128		pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
129		return ret;
130	}
131
132	ret = usb_control_msg(gspca_dev->dev,
133			      usb_sndctrlpipe(gspca_dev->dev, 0),
134			      USB_REQ_SYNCH_FRAME,                /* request */
135			      USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
136			      SQ905_PING, 0, gspca_dev->usb_buf, 1,
137			      SQ905_CMD_TIMEOUT);
138	if (ret < 0) {
139		pr_err("%s: usb_control_msg failed 2 (%d)\n", __func__, ret);
140		return ret;
141	}
142
143	return 0;
144}
145
146/*
147 * Acknowledge the end of a frame - see warning on sq905_command.
148 */
149static int sq905_ack_frame(struct gspca_dev *gspca_dev)
150{
151	int ret;
152
153	gspca_dev->usb_buf[0] = '\0';
154	ret = usb_control_msg(gspca_dev->dev,
155			      usb_sndctrlpipe(gspca_dev->dev, 0),
156			      USB_REQ_SYNCH_FRAME,                /* request */
157			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
158			      SQ905_READ_DONE, 0, gspca_dev->usb_buf, 1,
159			      SQ905_CMD_TIMEOUT);
160	if (ret < 0) {
161		pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
162		return ret;
163	}
164
165	return 0;
166}
167
168/*
169 *  request and read a block of data - see warning on sq905_command.
170 */
171static int
172sq905_read_data(struct gspca_dev *gspca_dev, u8 *data, int size, int need_lock)
173{
174	int ret;
175	int act_len;
176
177	gspca_dev->usb_buf[0] = '\0';
178	if (need_lock)
179		mutex_lock(&gspca_dev->usb_lock);
180	ret = usb_control_msg(gspca_dev->dev,
181			      usb_sndctrlpipe(gspca_dev->dev, 0),
182			      USB_REQ_SYNCH_FRAME,                /* request */
183			      USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
184			      SQ905_BULK_READ, size, gspca_dev->usb_buf,
185			      1, SQ905_CMD_TIMEOUT);
186	if (need_lock)
187		mutex_unlock(&gspca_dev->usb_lock);
188	if (ret < 0) {
189		pr_err("%s: usb_control_msg failed (%d)\n", __func__, ret);
190		return ret;
191	}
192	ret = usb_bulk_msg(gspca_dev->dev,
193			   usb_rcvbulkpipe(gspca_dev->dev, 0x81),
194			   data, size, &act_len, SQ905_DATA_TIMEOUT);
195
196	/* successful, it returns 0, otherwise  negative */
197	if (ret < 0 || act_len != size) {
198		pr_err("bulk read fail (%d) len %d/%d\n", ret, act_len, size);
199		return -EIO;
200	}
201	return 0;
202}
203
204/* This function is called as a workqueue function and runs whenever the camera
205 * is streaming data. Because it is a workqueue function it is allowed to sleep
206 * so we can use synchronous USB calls. To avoid possible collisions with other
207 * threads attempting to use the camera's USB interface we take the gspca
208 * usb_lock when performing USB operations. In practice the only thing we need
209 * to protect against is the usb_set_interface call that gspca makes during
210 * stream_off as the camera doesn't provide any controls that the user could try
211 * to change.
212 */
213static void sq905_dostream(struct work_struct *work)
214{
215	struct sd *dev = container_of(work, struct sd, work_struct);
216	struct gspca_dev *gspca_dev = &dev->gspca_dev;
217	int bytes_left; /* bytes remaining in current frame. */
218	int data_len;   /* size to use for the next read. */
219	int header_read; /* true if we have already read the frame header. */
220	int packet_type;
221	int frame_sz;
222	int ret;
223	u8 *data;
224	u8 *buffer;
225
226	buffer = kmalloc(SQ905_MAX_TRANSFER, GFP_KERNEL | GFP_DMA);
227	if (!buffer) {
228		pr_err("Couldn't allocate USB buffer\n");
229		goto quit_stream;
230	}
231
232	frame_sz = gspca_dev->cam.cam_mode[gspca_dev->curr_mode].sizeimage
233			+ FRAME_HEADER_LEN;
234
235	while (gspca_dev->present && gspca_dev->streaming) {
236		/* request some data and then read it until we have
237		 * a complete frame. */
238		bytes_left = frame_sz;
239		header_read = 0;
240
241		/* Note we do not check for gspca_dev->streaming here, as
242		   we must finish reading an entire frame, otherwise the
243		   next time we stream we start reading in the middle of a
244		   frame. */
245		while (bytes_left > 0 && gspca_dev->present) {
246			data_len = bytes_left > SQ905_MAX_TRANSFER ?
247				SQ905_MAX_TRANSFER : bytes_left;
248			ret = sq905_read_data(gspca_dev, buffer, data_len, 1);
249			if (ret < 0)
250				goto quit_stream;
251			PDEBUG(D_PACK,
252				"Got %d bytes out of %d for frame",
253				data_len, bytes_left);
254			bytes_left -= data_len;
255			data = buffer;
256			if (!header_read) {
257				packet_type = FIRST_PACKET;
258				/* The first 64 bytes of each frame are
259				 * a header full of FF 00 bytes */
260				data += FRAME_HEADER_LEN;
261				data_len -= FRAME_HEADER_LEN;
262				header_read = 1;
263			} else if (bytes_left == 0) {
264				packet_type = LAST_PACKET;
265			} else {
266				packet_type = INTER_PACKET;
267			}
268			gspca_frame_add(gspca_dev, packet_type,
269					data, data_len);
270			/* If entire frame fits in one packet we still
271			   need to add a LAST_PACKET */
272			if (packet_type == FIRST_PACKET &&
273			    bytes_left == 0)
274				gspca_frame_add(gspca_dev, LAST_PACKET,
275						NULL, 0);
276		}
277		if (gspca_dev->present) {
278			/* acknowledge the frame */
279			mutex_lock(&gspca_dev->usb_lock);
280			ret = sq905_ack_frame(gspca_dev);
281			mutex_unlock(&gspca_dev->usb_lock);
282			if (ret < 0)
283				goto quit_stream;
284		}
285	}
286quit_stream:
287	if (gspca_dev->present) {
288		mutex_lock(&gspca_dev->usb_lock);
289		sq905_command(gspca_dev, SQ905_CLEAR);
290		mutex_unlock(&gspca_dev->usb_lock);
291	}
292	kfree(buffer);
293}
294
295/* This function is called at probe time just before sd_init */
296static int sd_config(struct gspca_dev *gspca_dev,
297		const struct usb_device_id *id)
298{
299	struct cam *cam = &gspca_dev->cam;
300	struct sd *dev = (struct sd *) gspca_dev;
301
302	/* We don't use the buffer gspca allocates so make it small. */
303	cam->bulk = 1;
304	cam->bulk_size = 64;
305
306	INIT_WORK(&dev->work_struct, sq905_dostream);
307
308	return 0;
309}
310
311/* called on streamoff with alt==0 and on disconnect */
312/* the usb_lock is held at entry - restore on exit */
313static void sd_stop0(struct gspca_dev *gspca_dev)
314{
315	struct sd *dev = (struct sd *) gspca_dev;
316
317	/* wait for the work queue to terminate */
318	mutex_unlock(&gspca_dev->usb_lock);
319	/* This waits for sq905_dostream to finish */
320	destroy_workqueue(dev->work_thread);
321	dev->work_thread = NULL;
322	mutex_lock(&gspca_dev->usb_lock);
323}
324
325/* this function is called at probe and resume time */
326static int sd_init(struct gspca_dev *gspca_dev)
327{
328	u32 ident;
329	int ret;
330
331	/* connect to the camera and read
332	 * the model ID and process that and put it away.
333	 */
334	ret = sq905_command(gspca_dev, SQ905_CLEAR);
335	if (ret < 0)
336		return ret;
337	ret = sq905_command(gspca_dev, SQ905_ID);
338	if (ret < 0)
339		return ret;
340	ret = sq905_read_data(gspca_dev, gspca_dev->usb_buf, 4, 0);
341	if (ret < 0)
342		return ret;
343	/* usb_buf is allocated with kmalloc so is aligned.
344	 * Camera model number is the right way round if we assume this
345	 * reverse engineered ID is supposed to be big endian. */
346	ident = be32_to_cpup((__be32 *)gspca_dev->usb_buf);
347	ret = sq905_command(gspca_dev, SQ905_CLEAR);
348	if (ret < 0)
349		return ret;
350	PDEBUG(D_CONF, "SQ905 camera ID %08x detected", ident);
351	gspca_dev->cam.cam_mode = sq905_mode;
352	gspca_dev->cam.nmodes = ARRAY_SIZE(sq905_mode);
353	if (!(ident & SQ905_HIRES_MASK))
354		gspca_dev->cam.nmodes--;
355
356	if (ident & SQ905_ORIENTATION_MASK)
357		gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP;
358	else
359		gspca_dev->cam.input_flags = V4L2_IN_ST_VFLIP |
360					     V4L2_IN_ST_HFLIP;
361	return 0;
362}
363
364/* Set up for getting frames. */
365static int sd_start(struct gspca_dev *gspca_dev)
366{
367	struct sd *dev = (struct sd *) gspca_dev;
368	int ret;
369
370	/* "Open the shutter" and set size, to start capture */
371	switch (gspca_dev->curr_mode) {
372	default:
373/*	case 2: */
374		PDEBUG(D_STREAM, "Start streaming at high resolution");
375		ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_HIGH);
376		break;
377	case 1:
378		PDEBUG(D_STREAM, "Start streaming at medium resolution");
379		ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_MED);
380		break;
381	case 0:
382		PDEBUG(D_STREAM, "Start streaming at low resolution");
383		ret = sq905_command(&dev->gspca_dev, SQ905_CAPTURE_LOW);
384	}
385
386	if (ret < 0) {
387		PDEBUG(D_ERR, "Start streaming command failed");
388		return ret;
389	}
390	/* Start the workqueue function to do the streaming */
391	dev->work_thread = create_singlethread_workqueue(MODULE_NAME);
392	queue_work(dev->work_thread, &dev->work_struct);
393
394	return 0;
395}
396
397/* Table of supported USB devices */
398static const struct usb_device_id device_table[] = {
399	{USB_DEVICE(0x2770, 0x9120)},
400	{}
401};
402
403MODULE_DEVICE_TABLE(usb, device_table);
404
405/* sub-driver description */
406static const struct sd_desc sd_desc = {
407	.name   = MODULE_NAME,
408	.config = sd_config,
409	.init   = sd_init,
410	.start  = sd_start,
411	.stop0  = sd_stop0,
412};
413
414/* -- device connect -- */
415static int sd_probe(struct usb_interface *intf,
416		const struct usb_device_id *id)
417{
418	return gspca_dev_probe(intf, id,
419			&sd_desc,
420			sizeof(struct sd),
421			THIS_MODULE);
422}
423
424static struct usb_driver sd_driver = {
425	.name       = MODULE_NAME,
426	.id_table   = device_table,
427	.probe      = sd_probe,
428	.disconnect = gspca_disconnect,
429#ifdef CONFIG_PM
430	.suspend = gspca_suspend,
431	.resume  = gspca_resume,
432#endif
433};
434
435module_usb_driver(sd_driver);
436