xref: /linux/drivers/media/usb/uvc/uvc_status.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
1 /*
2  *      uvc_status.c  --  USB Video Class driver - Status endpoint
3  *
4  *      Copyright (C) 2005-2009
5  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
6  *
7  *      This program is free software; you can redistribute it and/or modify
8  *      it under the terms of the GNU General Public License as published by
9  *      the Free Software Foundation; either version 2 of the License, or
10  *      (at your option) any later version.
11  *
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/input.h>
16 #include <linux/slab.h>
17 #include <linux/usb.h>
18 #include <linux/usb/input.h>
19 
20 #include "uvcvideo.h"
21 
22 /* --------------------------------------------------------------------------
23  * Input device
24  */
25 #ifdef CONFIG_USB_VIDEO_CLASS_INPUT_EVDEV
26 static int uvc_input_init(struct uvc_device *dev)
27 {
28 	struct input_dev *input;
29 	int ret;
30 
31 	input = input_allocate_device();
32 	if (input == NULL)
33 		return -ENOMEM;
34 
35 	usb_make_path(dev->udev, dev->input_phys, sizeof(dev->input_phys));
36 	strlcat(dev->input_phys, "/button", sizeof(dev->input_phys));
37 
38 	input->name = dev->name;
39 	input->phys = dev->input_phys;
40 	usb_to_input_id(dev->udev, &input->id);
41 	input->dev.parent = &dev->intf->dev;
42 
43 	__set_bit(EV_KEY, input->evbit);
44 	__set_bit(KEY_CAMERA, input->keybit);
45 
46 	if ((ret = input_register_device(input)) < 0)
47 		goto error;
48 
49 	dev->input = input;
50 	return 0;
51 
52 error:
53 	input_free_device(input);
54 	return ret;
55 }
56 
57 static void uvc_input_cleanup(struct uvc_device *dev)
58 {
59 	if (dev->input)
60 		input_unregister_device(dev->input);
61 }
62 
63 static void uvc_input_report_key(struct uvc_device *dev, unsigned int code,
64 	int value)
65 {
66 	if (dev->input) {
67 		input_report_key(dev->input, code, value);
68 		input_sync(dev->input);
69 	}
70 }
71 
72 #else
73 #define uvc_input_init(dev)
74 #define uvc_input_cleanup(dev)
75 #define uvc_input_report_key(dev, code, value)
76 #endif /* CONFIG_USB_VIDEO_CLASS_INPUT_EVDEV */
77 
78 /* --------------------------------------------------------------------------
79  * Status interrupt endpoint
80  */
81 static void uvc_event_streaming(struct uvc_device *dev, __u8 *data, int len)
82 {
83 	if (len < 3) {
84 		uvc_trace(UVC_TRACE_STATUS, "Invalid streaming status event "
85 				"received.\n");
86 		return;
87 	}
88 
89 	if (data[2] == 0) {
90 		if (len < 4)
91 			return;
92 		uvc_trace(UVC_TRACE_STATUS, "Button (intf %u) %s len %d\n",
93 			data[1], data[3] ? "pressed" : "released", len);
94 		uvc_input_report_key(dev, KEY_CAMERA, data[3]);
95 	} else {
96 		uvc_trace(UVC_TRACE_STATUS, "Stream %u error event %02x %02x "
97 			"len %d.\n", data[1], data[2], data[3], len);
98 	}
99 }
100 
101 static void uvc_event_control(struct uvc_device *dev, __u8 *data, int len)
102 {
103 	char *attrs[3] = { "value", "info", "failure" };
104 
105 	if (len < 6 || data[2] != 0 || data[4] > 2) {
106 		uvc_trace(UVC_TRACE_STATUS, "Invalid control status event "
107 				"received.\n");
108 		return;
109 	}
110 
111 	uvc_trace(UVC_TRACE_STATUS, "Control %u/%u %s change len %d.\n",
112 		data[1], data[3], attrs[data[4]], len);
113 }
114 
115 static void uvc_status_complete(struct urb *urb)
116 {
117 	struct uvc_device *dev = urb->context;
118 	int len, ret;
119 
120 	switch (urb->status) {
121 	case 0:
122 		break;
123 
124 	case -ENOENT:		/* usb_kill_urb() called. */
125 	case -ECONNRESET:	/* usb_unlink_urb() called. */
126 	case -ESHUTDOWN:	/* The endpoint is being disabled. */
127 	case -EPROTO:		/* Device is disconnected (reported by some
128 				 * host controller). */
129 		return;
130 
131 	default:
132 		uvc_printk(KERN_WARNING, "Non-zero status (%d) in status "
133 			"completion handler.\n", urb->status);
134 		return;
135 	}
136 
137 	len = urb->actual_length;
138 	if (len > 0) {
139 		switch (dev->status[0] & 0x0f) {
140 		case UVC_STATUS_TYPE_CONTROL:
141 			uvc_event_control(dev, dev->status, len);
142 			break;
143 
144 		case UVC_STATUS_TYPE_STREAMING:
145 			uvc_event_streaming(dev, dev->status, len);
146 			break;
147 
148 		default:
149 			uvc_trace(UVC_TRACE_STATUS, "Unknown status event "
150 				"type %u.\n", dev->status[0]);
151 			break;
152 		}
153 	}
154 
155 	/* Resubmit the URB. */
156 	urb->interval = dev->int_ep->desc.bInterval;
157 	if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
158 		uvc_printk(KERN_ERR, "Failed to resubmit status URB (%d).\n",
159 			ret);
160 	}
161 }
162 
163 int uvc_status_init(struct uvc_device *dev)
164 {
165 	struct usb_host_endpoint *ep = dev->int_ep;
166 	unsigned int pipe;
167 	int interval;
168 
169 	if (ep == NULL)
170 		return 0;
171 
172 	uvc_input_init(dev);
173 
174 	dev->status = kzalloc(UVC_MAX_STATUS_SIZE, GFP_KERNEL);
175 	if (dev->status == NULL)
176 		return -ENOMEM;
177 
178 	dev->int_urb = usb_alloc_urb(0, GFP_KERNEL);
179 	if (dev->int_urb == NULL) {
180 		kfree(dev->status);
181 		return -ENOMEM;
182 	}
183 
184 	pipe = usb_rcvintpipe(dev->udev, ep->desc.bEndpointAddress);
185 
186 	/* For high-speed interrupt endpoints, the bInterval value is used as
187 	 * an exponent of two. Some developers forgot about it.
188 	 */
189 	interval = ep->desc.bInterval;
190 	if (interval > 16 && dev->udev->speed == USB_SPEED_HIGH &&
191 	    (dev->quirks & UVC_QUIRK_STATUS_INTERVAL))
192 		interval = fls(interval) - 1;
193 
194 	usb_fill_int_urb(dev->int_urb, dev->udev, pipe,
195 		dev->status, UVC_MAX_STATUS_SIZE, uvc_status_complete,
196 		dev, interval);
197 
198 	return 0;
199 }
200 
201 void uvc_status_cleanup(struct uvc_device *dev)
202 {
203 	usb_kill_urb(dev->int_urb);
204 	usb_free_urb(dev->int_urb);
205 	kfree(dev->status);
206 	uvc_input_cleanup(dev);
207 }
208 
209 int uvc_status_start(struct uvc_device *dev, gfp_t flags)
210 {
211 	if (dev->int_urb == NULL)
212 		return 0;
213 
214 	return usb_submit_urb(dev->int_urb, flags);
215 }
216 
217 void uvc_status_stop(struct uvc_device *dev)
218 {
219 	usb_kill_urb(dev->int_urb);
220 }
221