1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Benq DC E300 subdriver
4 *
5 * Copyright (C) 2009 Jean-Francois Moine (http://moinejf.free.fr)
6 */
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#define MODULE_NAME "benq"
11
12#include "gspca.h"
13
14MODULE_AUTHOR("Jean-Francois Moine <http://moinejf.free.fr>");
15MODULE_DESCRIPTION("Benq DC E300 USB Camera Driver");
16MODULE_LICENSE("GPL");
17
18/* specific webcam descriptor */
19struct sd {
20	struct gspca_dev gspca_dev;	/* !! must be the first item */
21};
22
23static const struct v4l2_pix_format vga_mode[] = {
24	{320, 240, V4L2_PIX_FMT_JPEG, V4L2_FIELD_NONE,
25		.bytesperline = 320,
26		.sizeimage = 320 * 240 * 3 / 8 + 590,
27		.colorspace = V4L2_COLORSPACE_JPEG},
28};
29
30static void sd_isoc_irq(struct urb *urb);
31
32/* -- write a register -- */
33static void reg_w(struct gspca_dev *gspca_dev,
34			u16 value, u16 index)
35{
36	struct usb_device *dev = gspca_dev->dev;
37	int ret;
38
39	if (gspca_dev->usb_err < 0)
40		return;
41	ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
42			0x02,
43			USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
44			value,
45			index,
46			NULL,
47			0,
48			500);
49	if (ret < 0) {
50		pr_err("reg_w err %d\n", ret);
51		gspca_dev->usb_err = ret;
52	}
53}
54
55/* this function is called at probe time */
56static int sd_config(struct gspca_dev *gspca_dev,
57			const struct usb_device_id *id)
58{
59	gspca_dev->cam.cam_mode = vga_mode;
60	gspca_dev->cam.nmodes = ARRAY_SIZE(vga_mode);
61	gspca_dev->cam.no_urb_create = 1;
62	return 0;
63}
64
65/* this function is called at probe and resume time */
66static int sd_init(struct gspca_dev *gspca_dev)
67{
68	return 0;
69}
70
71/* -- start the camera -- */
72static int sd_start(struct gspca_dev *gspca_dev)
73{
74	struct urb *urb;
75	int i, n;
76
77	/* create 4 URBs - 2 on endpoint 0x83 and 2 on 0x082 */
78#if MAX_NURBS < 4
79#error "Not enough URBs in the gspca table"
80#endif
81#define SD_PKT_SZ 64
82#define SD_NPKT 32
83	for (n = 0; n < 4; n++) {
84		urb = usb_alloc_urb(SD_NPKT, GFP_KERNEL);
85		if (!urb)
86			return -ENOMEM;
87		gspca_dev->urb[n] = urb;
88		urb->transfer_buffer = usb_alloc_coherent(gspca_dev->dev,
89						SD_PKT_SZ * SD_NPKT,
90						GFP_KERNEL,
91						&urb->transfer_dma);
92
93		if (urb->transfer_buffer == NULL) {
94			pr_err("usb_alloc_coherent failed\n");
95			return -ENOMEM;
96		}
97		urb->dev = gspca_dev->dev;
98		urb->context = gspca_dev;
99		urb->transfer_buffer_length = SD_PKT_SZ * SD_NPKT;
100		urb->pipe = usb_rcvisocpipe(gspca_dev->dev,
101					n & 1 ? 0x82 : 0x83);
102		urb->transfer_flags = URB_ISO_ASAP
103					| URB_NO_TRANSFER_DMA_MAP;
104		urb->interval = 1;
105		urb->complete = sd_isoc_irq;
106		urb->number_of_packets = SD_NPKT;
107		for (i = 0; i < SD_NPKT; i++) {
108			urb->iso_frame_desc[i].length = SD_PKT_SZ;
109			urb->iso_frame_desc[i].offset = SD_PKT_SZ * i;
110		}
111	}
112
113	return gspca_dev->usb_err;
114}
115
116static void sd_stopN(struct gspca_dev *gspca_dev)
117{
118	struct usb_interface *intf;
119
120	reg_w(gspca_dev, 0x003c, 0x0003);
121	reg_w(gspca_dev, 0x003c, 0x0004);
122	reg_w(gspca_dev, 0x003c, 0x0005);
123	reg_w(gspca_dev, 0x003c, 0x0006);
124	reg_w(gspca_dev, 0x003c, 0x0007);
125
126	intf = usb_ifnum_to_if(gspca_dev->dev, gspca_dev->iface);
127	usb_set_interface(gspca_dev->dev, gspca_dev->iface,
128					intf->num_altsetting - 1);
129}
130
131static void sd_pkt_scan(struct gspca_dev *gspca_dev,
132			u8 *data,		/* isoc packet */
133			int len)		/* iso packet length */
134{
135	/* unused */
136}
137
138/* reception of an URB */
139static void sd_isoc_irq(struct urb *urb)
140{
141	struct gspca_dev *gspca_dev = (struct gspca_dev *) urb->context;
142	struct urb *urb0;
143	u8 *data;
144	int i, st;
145
146	gspca_dbg(gspca_dev, D_PACK, "sd isoc irq\n");
147	if (!gspca_dev->streaming)
148		return;
149	if (urb->status != 0) {
150		if (urb->status == -ESHUTDOWN)
151			return;		/* disconnection */
152#ifdef CONFIG_PM
153		if (gspca_dev->frozen)
154			return;
155#endif
156		pr_err("urb status: %d\n", urb->status);
157		return;
158	}
159
160	/* if this is a control URN (ep 0x83), wait */
161	if (urb == gspca_dev->urb[0] || urb == gspca_dev->urb[2])
162		return;
163
164	/* scan both received URBs */
165	if (urb == gspca_dev->urb[1])
166		urb0 = gspca_dev->urb[0];
167	else
168		urb0 = gspca_dev->urb[2];
169	for (i = 0; i < urb->number_of_packets; i++) {
170
171		/* check the packet status and length */
172		if (urb0->iso_frame_desc[i].actual_length != SD_PKT_SZ
173		    || urb->iso_frame_desc[i].actual_length != SD_PKT_SZ) {
174			gspca_err(gspca_dev, "ISOC bad lengths %d / %d\n",
175				  urb0->iso_frame_desc[i].actual_length,
176				  urb->iso_frame_desc[i].actual_length);
177			gspca_dev->last_packet_type = DISCARD_PACKET;
178			continue;
179		}
180		st = urb0->iso_frame_desc[i].status;
181		if (st == 0)
182			st = urb->iso_frame_desc[i].status;
183		if (st) {
184			pr_err("ISOC data error: [%d] status=%d\n",
185				i, st);
186			gspca_dev->last_packet_type = DISCARD_PACKET;
187			continue;
188		}
189
190		/*
191		 * The images are received in URBs of different endpoints
192		 * (0x83 and 0x82).
193		 * Image pieces in URBs of ep 0x83 are continuated in URBs of
194		 * ep 0x82 of the same index.
195		 * The packets in the URBs of endpoint 0x83 start with:
196		 *	- 80 ba/bb 00 00 = start of image followed by 'ff d8'
197		 *	- 04 ba/bb oo oo = image piece
198		 *		where 'oo oo' is the image offset
199						(not checked)
200		 *	- (other -> bad frame)
201		 * The images are JPEG encoded with full header and
202		 * normal ff escape.
203		 * The end of image ('ff d9') may occur in any URB.
204		 * (not checked)
205		 */
206		data = (u8 *) urb0->transfer_buffer
207					+ urb0->iso_frame_desc[i].offset;
208		if (data[0] == 0x80 && (data[1] & 0xfe) == 0xba) {
209
210			/* new image */
211			gspca_frame_add(gspca_dev, LAST_PACKET,
212					NULL, 0);
213			gspca_frame_add(gspca_dev, FIRST_PACKET,
214					data + 4, SD_PKT_SZ - 4);
215		} else if (data[0] == 0x04 && (data[1] & 0xfe) == 0xba) {
216			gspca_frame_add(gspca_dev, INTER_PACKET,
217					data + 4, SD_PKT_SZ - 4);
218		} else {
219			gspca_dev->last_packet_type = DISCARD_PACKET;
220			continue;
221		}
222		data = (u8 *) urb->transfer_buffer
223					+ urb->iso_frame_desc[i].offset;
224		gspca_frame_add(gspca_dev, INTER_PACKET,
225				data, SD_PKT_SZ);
226	}
227
228	/* resubmit the URBs */
229	st = usb_submit_urb(urb0, GFP_ATOMIC);
230	if (st < 0)
231		pr_err("usb_submit_urb(0) ret %d\n", st);
232	st = usb_submit_urb(urb, GFP_ATOMIC);
233	if (st < 0)
234		pr_err("usb_submit_urb() ret %d\n", st);
235}
236
237/* sub-driver description */
238static const struct sd_desc sd_desc = {
239	.name = MODULE_NAME,
240	.config = sd_config,
241	.init = sd_init,
242	.start = sd_start,
243	.stopN = sd_stopN,
244	.pkt_scan = sd_pkt_scan,
245};
246
247/* -- module initialisation -- */
248static const struct usb_device_id device_table[] = {
249	{USB_DEVICE(0x04a5, 0x3035)},
250	{}
251};
252MODULE_DEVICE_TABLE(usb, device_table);
253
254/* -- device connect -- */
255static int sd_probe(struct usb_interface *intf,
256			const struct usb_device_id *id)
257{
258	return gspca_dev_probe(intf, id, &sd_desc, sizeof(struct sd),
259				THIS_MODULE);
260}
261
262static struct usb_driver sd_driver = {
263	.name = MODULE_NAME,
264	.id_table = device_table,
265	.probe = sd_probe,
266	.disconnect = gspca_disconnect,
267#ifdef CONFIG_PM
268	.suspend = gspca_suspend,
269	.resume = gspca_resume,
270	.reset_resume = gspca_resume,
271#endif
272};
273
274module_usb_driver(sd_driver);
275