1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2012 Red Hat
4 *
5 * based in parts on udlfb.c:
6 * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it>
7 * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com>
8 * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com>
9 */
10
11 #include <drm/drm.h>
12 #include <drm/drm_print.h>
13 #include <drm/drm_probe_helper.h>
14
15 #include "udl_drv.h"
16
17 /* -BULK_SIZE as per usb-skeleton. Can we get full page and avoid overhead? */
18 #define BULK_SIZE 512
19
20 #define NR_USB_REQUEST_CHANNEL 0x12
21
22 #define MAX_TRANSFER (PAGE_SIZE*16 - BULK_SIZE)
23 #define WRITES_IN_FLIGHT (20)
24 #define MAX_VENDOR_DESCRIPTOR_SIZE 256
25
26 static struct urb *udl_get_urb_locked(struct udl_device *udl, long timeout);
27
udl_parse_vendor_descriptor(struct udl_device * udl)28 static int udl_parse_vendor_descriptor(struct udl_device *udl)
29 {
30 struct usb_device *udev = udl_to_usb_device(udl);
31 char *desc;
32 char *buf;
33 char *desc_end;
34
35 u8 total_len = 0;
36
37 buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL);
38 if (!buf)
39 return false;
40 desc = buf;
41
42 total_len = usb_get_descriptor(udev, 0x5f, /* vendor specific */
43 0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
44 if (total_len > 5) {
45 DRM_INFO("vendor descriptor length:%x data:%11ph\n",
46 total_len, desc);
47
48 if ((desc[0] != total_len) || /* descriptor length */
49 (desc[1] != 0x5f) || /* vendor descriptor type */
50 (desc[2] != 0x01) || /* version (2 bytes) */
51 (desc[3] != 0x00) ||
52 (desc[4] != total_len - 2)) /* length after type */
53 goto unrecognized;
54
55 desc_end = desc + total_len;
56 desc += 5; /* the fixed header we've already parsed */
57
58 while (desc < desc_end) {
59 u8 length;
60 u16 key;
61
62 key = le16_to_cpu(*((u16 *) desc));
63 desc += sizeof(u16);
64 length = *desc;
65 desc++;
66
67 switch (key) {
68 case 0x0200: { /* max_area */
69 u32 max_area;
70 max_area = le32_to_cpu(*((u32 *)desc));
71 DRM_DEBUG("DL chip limited to %d pixel modes\n",
72 max_area);
73 udl->sku_pixel_limit = max_area;
74 break;
75 }
76 default:
77 break;
78 }
79 desc += length;
80 }
81 }
82
83 goto success;
84
85 unrecognized:
86 /* allow udlfb to load for now even if firmware unrecognized */
87 DRM_ERROR("Unrecognized vendor firmware descriptor\n");
88
89 success:
90 kfree(buf);
91 return true;
92 }
93
94 /*
95 * Need to ensure a channel is selected before submitting URBs
96 */
udl_select_std_channel(struct udl_device * udl)97 int udl_select_std_channel(struct udl_device *udl)
98 {
99 static const u8 set_def_chn[] = {0x57, 0xCD, 0xDC, 0xA7,
100 0x1C, 0x88, 0x5E, 0x15,
101 0x60, 0xFE, 0xC6, 0x97,
102 0x16, 0x3D, 0x47, 0xF2};
103
104 void *sendbuf;
105 int ret;
106 struct usb_device *udev = udl_to_usb_device(udl);
107
108 sendbuf = kmemdup(set_def_chn, sizeof(set_def_chn), GFP_KERNEL);
109 if (!sendbuf)
110 return -ENOMEM;
111
112 ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
113 NR_USB_REQUEST_CHANNEL,
114 (USB_DIR_OUT | USB_TYPE_VENDOR), 0, 0,
115 sendbuf, sizeof(set_def_chn),
116 USB_CTRL_SET_TIMEOUT);
117 kfree(sendbuf);
118 return ret < 0 ? ret : 0;
119 }
120
udl_urb_completion(struct urb * urb)121 void udl_urb_completion(struct urb *urb)
122 {
123 struct urb_node *unode = urb->context;
124 struct udl_device *udl = unode->dev;
125 unsigned long flags;
126
127 /* sync/async unlink faults aren't errors */
128 if (urb->status) {
129 if (!(urb->status == -ENOENT ||
130 urb->status == -ECONNRESET ||
131 urb->status == -EPROTO ||
132 urb->status == -ESHUTDOWN)) {
133 DRM_ERROR("%s - nonzero write bulk status received: %d\n",
134 __func__, urb->status);
135 }
136 }
137
138 urb->transfer_buffer_length = udl->urbs.size; /* reset to actual */
139
140 spin_lock_irqsave(&udl->urbs.lock, flags);
141 list_add_tail(&unode->entry, &udl->urbs.list);
142 udl->urbs.available++;
143 spin_unlock_irqrestore(&udl->urbs.lock, flags);
144
145 wake_up(&udl->urbs.sleep);
146 }
147
udl_free_urb_list(struct drm_device * dev)148 static void udl_free_urb_list(struct drm_device *dev)
149 {
150 struct udl_device *udl = to_udl(dev);
151 struct urb_node *unode;
152 struct urb *urb;
153
154 DRM_DEBUG("Waiting for completes and freeing all render urbs\n");
155
156 /* keep waiting and freeing, until we've got 'em all */
157 while (udl->urbs.count) {
158 spin_lock_irq(&udl->urbs.lock);
159 urb = udl_get_urb_locked(udl, MAX_SCHEDULE_TIMEOUT);
160 udl->urbs.count--;
161 spin_unlock_irq(&udl->urbs.lock);
162 if (WARN_ON(!urb))
163 break;
164 unode = urb->context;
165 /* Free each separately allocated piece */
166 usb_free_coherent(urb->dev, udl->urbs.size,
167 urb->transfer_buffer, urb->transfer_dma);
168 usb_free_urb(urb);
169 kfree(unode);
170 }
171
172 wake_up_all(&udl->urbs.sleep);
173 }
174
udl_alloc_urb_list(struct drm_device * dev,int count,size_t size)175 static int udl_alloc_urb_list(struct drm_device *dev, int count, size_t size)
176 {
177 struct udl_device *udl = to_udl(dev);
178 struct urb *urb;
179 struct urb_node *unode;
180 char *buf;
181 size_t wanted_size = count * size;
182 struct usb_device *udev = udl_to_usb_device(udl);
183
184 spin_lock_init(&udl->urbs.lock);
185 INIT_LIST_HEAD(&udl->urbs.list);
186 init_waitqueue_head(&udl->urbs.sleep);
187 udl->urbs.count = 0;
188 udl->urbs.available = 0;
189
190 retry:
191 udl->urbs.size = size;
192
193 while (udl->urbs.count * size < wanted_size) {
194 unode = kzalloc(sizeof(struct urb_node), GFP_KERNEL);
195 if (!unode)
196 break;
197 unode->dev = udl;
198
199 urb = usb_alloc_urb(0, GFP_KERNEL);
200 if (!urb) {
201 kfree(unode);
202 break;
203 }
204 unode->urb = urb;
205
206 buf = usb_alloc_coherent(udev, size, GFP_KERNEL,
207 &urb->transfer_dma);
208 if (!buf) {
209 kfree(unode);
210 usb_free_urb(urb);
211 if (size > PAGE_SIZE) {
212 size /= 2;
213 udl_free_urb_list(dev);
214 goto retry;
215 }
216 break;
217 }
218
219 /* urb->transfer_buffer_length set to actual before submit */
220 usb_fill_bulk_urb(urb, udev, usb_sndbulkpipe(udev, 1),
221 buf, size, udl_urb_completion, unode);
222 urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
223
224 list_add_tail(&unode->entry, &udl->urbs.list);
225
226 udl->urbs.count++;
227 udl->urbs.available++;
228 }
229
230 DRM_DEBUG("allocated %d %d byte urbs\n", udl->urbs.count, (int) size);
231
232 return udl->urbs.count;
233 }
234
udl_get_urb_locked(struct udl_device * udl,long timeout)235 static struct urb *udl_get_urb_locked(struct udl_device *udl, long timeout)
236 {
237 struct urb_node *unode;
238
239 assert_spin_locked(&udl->urbs.lock);
240
241 /* Wait for an in-flight buffer to complete and get re-queued */
242 if (!wait_event_lock_irq_timeout(udl->urbs.sleep,
243 !udl->urbs.count ||
244 !list_empty(&udl->urbs.list),
245 udl->urbs.lock, timeout)) {
246 DRM_INFO("wait for urb interrupted: available: %d\n",
247 udl->urbs.available);
248 return NULL;
249 }
250
251 if (!udl->urbs.count)
252 return NULL;
253
254 unode = list_first_entry(&udl->urbs.list, struct urb_node, entry);
255 list_del_init(&unode->entry);
256 udl->urbs.available--;
257
258 return unode->urb;
259 }
260
261 #define GET_URB_TIMEOUT HZ
udl_get_urb(struct drm_device * dev)262 struct urb *udl_get_urb(struct drm_device *dev)
263 {
264 struct udl_device *udl = to_udl(dev);
265 struct urb *urb;
266
267 spin_lock_irq(&udl->urbs.lock);
268 urb = udl_get_urb_locked(udl, GET_URB_TIMEOUT);
269 spin_unlock_irq(&udl->urbs.lock);
270 return urb;
271 }
272
udl_submit_urb(struct drm_device * dev,struct urb * urb,size_t len)273 int udl_submit_urb(struct drm_device *dev, struct urb *urb, size_t len)
274 {
275 struct udl_device *udl = to_udl(dev);
276 int ret;
277
278 if (WARN_ON(len > udl->urbs.size)) {
279 ret = -EINVAL;
280 goto error;
281 }
282 urb->transfer_buffer_length = len; /* set to actual payload len */
283 ret = usb_submit_urb(urb, GFP_ATOMIC);
284 error:
285 if (ret) {
286 udl_urb_completion(urb); /* because no one else will */
287 DRM_ERROR("usb_submit_urb error %x\n", ret);
288 }
289 return ret;
290 }
291
292 /* wait until all pending URBs have been processed */
udl_sync_pending_urbs(struct drm_device * dev)293 void udl_sync_pending_urbs(struct drm_device *dev)
294 {
295 struct udl_device *udl = to_udl(dev);
296
297 spin_lock_irq(&udl->urbs.lock);
298 /* 2 seconds as a sane timeout */
299 if (!wait_event_lock_irq_timeout(udl->urbs.sleep,
300 udl->urbs.available == udl->urbs.count,
301 udl->urbs.lock,
302 msecs_to_jiffies(2000)))
303 drm_err(dev, "Timeout for syncing pending URBs\n");
304 spin_unlock_irq(&udl->urbs.lock);
305 }
306
udl_init(struct udl_device * udl)307 int udl_init(struct udl_device *udl)
308 {
309 struct drm_device *dev = &udl->drm;
310 int ret = -ENOMEM;
311
312 DRM_DEBUG("\n");
313
314 udl->dmadev = usb_intf_get_dma_device(to_usb_interface(dev->dev));
315 if (!udl->dmadev)
316 drm_warn(dev, "buffer sharing not supported"); /* not an error */
317
318 mutex_init(&udl->gem_lock);
319
320 if (!udl_parse_vendor_descriptor(udl)) {
321 ret = -ENODEV;
322 DRM_ERROR("firmware not recognized. Assume incompatible device\n");
323 goto err;
324 }
325
326 if (udl_select_std_channel(udl))
327 DRM_ERROR("Selecting channel failed\n");
328
329 if (!udl_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
330 DRM_ERROR("udl_alloc_urb_list failed\n");
331 goto err;
332 }
333
334 DRM_DEBUG("\n");
335 ret = udl_modeset_init(dev);
336 if (ret)
337 goto err;
338
339 drm_kms_helper_poll_init(dev);
340
341 return 0;
342
343 err:
344 if (udl->urbs.count)
345 udl_free_urb_list(dev);
346 put_device(udl->dmadev);
347 DRM_ERROR("%d\n", ret);
348 return ret;
349 }
350
udl_drop_usb(struct drm_device * dev)351 int udl_drop_usb(struct drm_device *dev)
352 {
353 struct udl_device *udl = to_udl(dev);
354
355 udl_free_urb_list(dev);
356 put_device(udl->dmadev);
357 udl->dmadev = NULL;
358
359 return 0;
360 }
361