xref: /linux/drivers/gpu/drm/gud/gud_drv.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright 2020 Noralf Trønnes
4  */
5 
6 #include <linux/dma-buf.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/lz4.h>
9 #include <linux/module.h>
10 #include <linux/platform_device.h>
11 #include <linux/string_helpers.h>
12 #include <linux/usb.h>
13 #include <linux/vmalloc.h>
14 #include <linux/workqueue.h>
15 
16 #include <drm/drm_atomic_helper.h>
17 #include <drm/drm_blend.h>
18 #include <drm/drm_client_setup.h>
19 #include <drm/drm_damage_helper.h>
20 #include <drm/drm_debugfs.h>
21 #include <drm/drm_drv.h>
22 #include <drm/drm_fbdev_shmem.h>
23 #include <drm/drm_fourcc.h>
24 #include <drm/drm_gem_atomic_helper.h>
25 #include <drm/drm_gem_framebuffer_helper.h>
26 #include <drm/drm_gem_shmem_helper.h>
27 #include <drm/drm_managed.h>
28 #include <drm/drm_print.h>
29 #include <drm/drm_probe_helper.h>
30 #include <drm/drm_simple_kms_helper.h>
31 #include <drm/gud.h>
32 
33 #include "gud_internal.h"
34 
35 /* Only used internally */
36 static const struct drm_format_info gud_drm_format_r1 = {
37 	.format = GUD_DRM_FORMAT_R1,
38 	.num_planes = 1,
39 	.char_per_block = { 1, 0, 0 },
40 	.block_w = { 8, 0, 0 },
41 	.block_h = { 1, 0, 0 },
42 	.hsub = 1,
43 	.vsub = 1,
44 };
45 
46 static const struct drm_format_info gud_drm_format_xrgb1111 = {
47 	.format = GUD_DRM_FORMAT_XRGB1111,
48 	.num_planes = 1,
49 	.char_per_block = { 1, 0, 0 },
50 	.block_w = { 2, 0, 0 },
51 	.block_h = { 1, 0, 0 },
52 	.hsub = 1,
53 	.vsub = 1,
54 };
55 
56 static int gud_usb_control_msg(struct usb_interface *intf, bool in,
57 			       u8 request, u16 value, void *buf, size_t len)
58 {
59 	u8 requesttype = USB_TYPE_VENDOR | USB_RECIP_INTERFACE;
60 	u8 ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
61 	struct usb_device *usb = interface_to_usbdev(intf);
62 	unsigned int pipe;
63 
64 	if (len && !buf)
65 		return -EINVAL;
66 
67 	if (in) {
68 		pipe = usb_rcvctrlpipe(usb, 0);
69 		requesttype |= USB_DIR_IN;
70 	} else {
71 		pipe = usb_sndctrlpipe(usb, 0);
72 		requesttype |= USB_DIR_OUT;
73 	}
74 
75 	return usb_control_msg(usb, pipe, request, requesttype, value,
76 			       ifnum, buf, len, USB_CTRL_GET_TIMEOUT);
77 }
78 
79 static int gud_get_display_descriptor(struct usb_interface *intf,
80 				      struct gud_display_descriptor_req *desc)
81 {
82 	void *buf;
83 	int ret;
84 
85 	buf = kmalloc(sizeof(*desc), GFP_KERNEL);
86 	if (!buf)
87 		return -ENOMEM;
88 
89 	ret = gud_usb_control_msg(intf, true, GUD_REQ_GET_DESCRIPTOR, 0, buf, sizeof(*desc));
90 	memcpy(desc, buf, sizeof(*desc));
91 	kfree(buf);
92 	if (ret < 0)
93 		return ret;
94 	if (ret != sizeof(*desc))
95 		return -EIO;
96 
97 	if (desc->magic != le32_to_cpu(GUD_DISPLAY_MAGIC))
98 		return -ENODATA;
99 
100 	DRM_DEV_DEBUG_DRIVER(&intf->dev,
101 			     "version=%u flags=0x%x compression=0x%x max_buffer_size=%u\n",
102 			     desc->version, le32_to_cpu(desc->flags), desc->compression,
103 			     le32_to_cpu(desc->max_buffer_size));
104 
105 	if (!desc->version || !desc->max_width || !desc->max_height ||
106 	    le32_to_cpu(desc->min_width) > le32_to_cpu(desc->max_width) ||
107 	    le32_to_cpu(desc->min_height) > le32_to_cpu(desc->max_height))
108 		return -EINVAL;
109 
110 	return 0;
111 }
112 
113 static int gud_status_to_errno(u8 status)
114 {
115 	switch (status) {
116 	case GUD_STATUS_OK:
117 		return 0;
118 	case GUD_STATUS_BUSY:
119 		return -EBUSY;
120 	case GUD_STATUS_REQUEST_NOT_SUPPORTED:
121 		return -EOPNOTSUPP;
122 	case GUD_STATUS_PROTOCOL_ERROR:
123 		return -EPROTO;
124 	case GUD_STATUS_INVALID_PARAMETER:
125 		return -EINVAL;
126 	case GUD_STATUS_ERROR:
127 		return -EREMOTEIO;
128 	default:
129 		return -EREMOTEIO;
130 	}
131 }
132 
133 static int gud_usb_get_status(struct usb_interface *intf)
134 {
135 	int ret, status = -EIO;
136 	u8 *buf;
137 
138 	buf = kmalloc(sizeof(*buf), GFP_KERNEL);
139 	if (!buf)
140 		return -ENOMEM;
141 
142 	ret = gud_usb_control_msg(intf, true, GUD_REQ_GET_STATUS, 0, buf, sizeof(*buf));
143 	if (ret == sizeof(*buf))
144 		status = gud_status_to_errno(*buf);
145 	kfree(buf);
146 
147 	if (ret < 0)
148 		return ret;
149 
150 	return status;
151 }
152 
153 static int gud_usb_transfer(struct gud_device *gdrm, bool in, u8 request, u16 index,
154 			    void *buf, size_t len)
155 {
156 	struct usb_interface *intf = to_usb_interface(gdrm->drm.dev);
157 	int idx, ret;
158 
159 	drm_dbg(&gdrm->drm, "%s: request=0x%x index=%u len=%zu\n",
160 		in ? "get" : "set", request, index, len);
161 
162 	if (!drm_dev_enter(&gdrm->drm, &idx))
163 		return -ENODEV;
164 
165 	mutex_lock(&gdrm->ctrl_lock);
166 
167 	ret = gud_usb_control_msg(intf, in, request, index, buf, len);
168 	if (ret == -EPIPE || ((gdrm->flags & GUD_DISPLAY_FLAG_STATUS_ON_SET) && !in && ret >= 0)) {
169 		int status;
170 
171 		status = gud_usb_get_status(intf);
172 		if (status < 0) {
173 			ret = status;
174 		} else if (ret < 0) {
175 			dev_err_once(gdrm->drm.dev,
176 				     "Unexpected status OK for failed transfer\n");
177 			ret = -EPIPE;
178 		}
179 	}
180 
181 	if (ret < 0) {
182 		drm_dbg(&gdrm->drm, "ret=%d\n", ret);
183 		gdrm->stats_num_errors++;
184 	}
185 
186 	mutex_unlock(&gdrm->ctrl_lock);
187 	drm_dev_exit(idx);
188 
189 	return ret;
190 }
191 
192 /*
193  * @buf cannot be allocated on the stack.
194  * Returns number of bytes received or negative error code on failure.
195  */
196 int gud_usb_get(struct gud_device *gdrm, u8 request, u16 index, void *buf, size_t max_len)
197 {
198 	return gud_usb_transfer(gdrm, true, request, index, buf, max_len);
199 }
200 
201 /*
202  * @buf can be allocated on the stack or NULL.
203  * Returns zero on success or negative error code on failure.
204  */
205 int gud_usb_set(struct gud_device *gdrm, u8 request, u16 index, void *buf, size_t len)
206 {
207 	void *trbuf = NULL;
208 	int ret;
209 
210 	if (buf && len) {
211 		trbuf = kmemdup(buf, len, GFP_KERNEL);
212 		if (!trbuf)
213 			return -ENOMEM;
214 	}
215 
216 	ret = gud_usb_transfer(gdrm, false, request, index, trbuf, len);
217 	kfree(trbuf);
218 	if (ret < 0)
219 		return ret;
220 
221 	return ret != len ? -EIO : 0;
222 }
223 
224 /*
225  * @val can be allocated on the stack.
226  * Returns zero on success or negative error code on failure.
227  */
228 int gud_usb_get_u8(struct gud_device *gdrm, u8 request, u16 index, u8 *val)
229 {
230 	u8 *buf;
231 	int ret;
232 
233 	buf = kmalloc(sizeof(*val), GFP_KERNEL);
234 	if (!buf)
235 		return -ENOMEM;
236 
237 	ret = gud_usb_get(gdrm, request, index, buf, sizeof(*val));
238 	*val = *buf;
239 	kfree(buf);
240 	if (ret < 0)
241 		return ret;
242 
243 	return ret != sizeof(*val) ? -EIO : 0;
244 }
245 
246 /* Returns zero on success or negative error code on failure. */
247 int gud_usb_set_u8(struct gud_device *gdrm, u8 request, u8 val)
248 {
249 	return gud_usb_set(gdrm, request, 0, &val, sizeof(val));
250 }
251 
252 static int gud_get_properties(struct gud_device *gdrm)
253 {
254 	struct gud_property_req *properties;
255 	unsigned int i, num_properties;
256 	int ret;
257 
258 	properties = kcalloc(GUD_PROPERTIES_MAX_NUM, sizeof(*properties), GFP_KERNEL);
259 	if (!properties)
260 		return -ENOMEM;
261 
262 	ret = gud_usb_get(gdrm, GUD_REQ_GET_PROPERTIES, 0,
263 			  properties, GUD_PROPERTIES_MAX_NUM * sizeof(*properties));
264 	if (ret <= 0)
265 		goto out;
266 	if (ret % sizeof(*properties)) {
267 		ret = -EIO;
268 		goto out;
269 	}
270 
271 	num_properties = ret / sizeof(*properties);
272 	ret = 0;
273 
274 	gdrm->properties = drmm_kcalloc(&gdrm->drm, num_properties, sizeof(*gdrm->properties),
275 					GFP_KERNEL);
276 	if (!gdrm->properties) {
277 		ret = -ENOMEM;
278 		goto out;
279 	}
280 
281 	for (i = 0; i < num_properties; i++) {
282 		u16 prop = le16_to_cpu(properties[i].prop);
283 		u64 val = le64_to_cpu(properties[i].val);
284 
285 		switch (prop) {
286 		case GUD_PROPERTY_ROTATION:
287 			/*
288 			 * DRM UAPI matches the protocol so use the value directly,
289 			 * but mask out any additions on future devices.
290 			 */
291 			val &= GUD_ROTATION_MASK;
292 			ret = drm_plane_create_rotation_property(&gdrm->pipe.plane,
293 								 DRM_MODE_ROTATE_0, val);
294 			break;
295 		default:
296 			/* New ones might show up in future devices, skip those we don't know. */
297 			drm_dbg(&gdrm->drm, "Ignoring unknown property: %u\n", prop);
298 			continue;
299 		}
300 
301 		if (ret)
302 			goto out;
303 
304 		gdrm->properties[gdrm->num_properties++] = prop;
305 	}
306 out:
307 	kfree(properties);
308 
309 	return ret;
310 }
311 
312 /*
313  * FIXME: Dma-buf sharing requires DMA support by the importing device.
314  *        This function is a workaround to make USB devices work as well.
315  *        See todo.rst for how to fix the issue in the dma-buf framework.
316  */
317 static struct drm_gem_object *gud_gem_prime_import(struct drm_device *drm, struct dma_buf *dma_buf)
318 {
319 	struct gud_device *gdrm = to_gud_device(drm);
320 
321 	if (!gdrm->dmadev)
322 		return ERR_PTR(-ENODEV);
323 
324 	return drm_gem_prime_import_dev(drm, dma_buf, gdrm->dmadev);
325 }
326 
327 static int gud_stats_debugfs(struct seq_file *m, void *data)
328 {
329 	struct drm_debugfs_entry *entry = m->private;
330 	struct gud_device *gdrm = to_gud_device(entry->dev);
331 	char buf[10];
332 
333 	string_get_size(gdrm->bulk_len, 1, STRING_UNITS_2, buf, sizeof(buf));
334 	seq_printf(m, "Max buffer size: %s\n", buf);
335 	seq_printf(m, "Number of errors:  %u\n", gdrm->stats_num_errors);
336 
337 	seq_puts(m, "Compression:      ");
338 	if (gdrm->compression & GUD_COMPRESSION_LZ4)
339 		seq_puts(m, " lz4");
340 	if (!gdrm->compression)
341 		seq_puts(m, " none");
342 	seq_puts(m, "\n");
343 
344 	if (gdrm->compression) {
345 		u64 remainder;
346 		u64 ratio = div64_u64_rem(gdrm->stats_length, gdrm->stats_actual_length,
347 					  &remainder);
348 		u64 ratio_frac = div64_u64(remainder * 10, gdrm->stats_actual_length);
349 
350 		seq_printf(m, "Compression ratio: %llu.%llu\n", ratio, ratio_frac);
351 	}
352 
353 	return 0;
354 }
355 
356 static const struct drm_simple_display_pipe_funcs gud_pipe_funcs = {
357 	.check      = gud_pipe_check,
358 	.update	    = gud_pipe_update,
359 	DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS
360 };
361 
362 static const struct drm_mode_config_funcs gud_mode_config_funcs = {
363 	.fb_create = drm_gem_fb_create_with_dirty,
364 	.atomic_check = drm_atomic_helper_check,
365 	.atomic_commit = drm_atomic_helper_commit,
366 };
367 
368 static const u64 gud_pipe_modifiers[] = {
369 	DRM_FORMAT_MOD_LINEAR,
370 	DRM_FORMAT_MOD_INVALID
371 };
372 
373 DEFINE_DRM_GEM_FOPS(gud_fops);
374 
375 static const struct drm_driver gud_drm_driver = {
376 	.driver_features	= DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC,
377 	.fops			= &gud_fops,
378 	DRM_GEM_SHMEM_DRIVER_OPS,
379 	.gem_prime_import	= gud_gem_prime_import,
380 	DRM_FBDEV_SHMEM_DRIVER_OPS,
381 
382 	.name			= "gud",
383 	.desc			= "Generic USB Display",
384 	.date			= "20200422",
385 	.major			= 1,
386 	.minor			= 0,
387 };
388 
389 static int gud_alloc_bulk_buffer(struct gud_device *gdrm)
390 {
391 	unsigned int i, num_pages;
392 	struct page **pages;
393 	void *ptr;
394 	int ret;
395 
396 	gdrm->bulk_buf = vmalloc_32(gdrm->bulk_len);
397 	if (!gdrm->bulk_buf)
398 		return -ENOMEM;
399 
400 	num_pages = DIV_ROUND_UP(gdrm->bulk_len, PAGE_SIZE);
401 	pages = kmalloc_array(num_pages, sizeof(struct page *), GFP_KERNEL);
402 	if (!pages)
403 		return -ENOMEM;
404 
405 	for (i = 0, ptr = gdrm->bulk_buf; i < num_pages; i++, ptr += PAGE_SIZE)
406 		pages[i] = vmalloc_to_page(ptr);
407 
408 	ret = sg_alloc_table_from_pages(&gdrm->bulk_sgt, pages, num_pages,
409 					0, gdrm->bulk_len, GFP_KERNEL);
410 	kfree(pages);
411 
412 	return ret;
413 }
414 
415 static void gud_free_buffers_and_mutex(void *data)
416 {
417 	struct gud_device *gdrm = data;
418 
419 	vfree(gdrm->compress_buf);
420 	gdrm->compress_buf = NULL;
421 	sg_free_table(&gdrm->bulk_sgt);
422 	vfree(gdrm->bulk_buf);
423 	gdrm->bulk_buf = NULL;
424 	mutex_destroy(&gdrm->ctrl_lock);
425 }
426 
427 static int gud_probe(struct usb_interface *intf, const struct usb_device_id *id)
428 {
429 	const struct drm_format_info *xrgb8888_emulation_format = NULL;
430 	bool rgb565_supported = false, xrgb8888_supported = false;
431 	unsigned int num_formats_dev, num_formats = 0;
432 	struct usb_endpoint_descriptor *bulk_out;
433 	struct gud_display_descriptor_req desc;
434 	struct device *dev = &intf->dev;
435 	size_t max_buffer_size = 0;
436 	struct gud_device *gdrm;
437 	struct drm_device *drm;
438 	u8 *formats_dev;
439 	u32 *formats;
440 	int ret, i;
441 
442 	ret = usb_find_bulk_out_endpoint(intf->cur_altsetting, &bulk_out);
443 	if (ret)
444 		return ret;
445 
446 	ret = gud_get_display_descriptor(intf, &desc);
447 	if (ret) {
448 		DRM_DEV_DEBUG_DRIVER(dev, "Not a display interface: ret=%d\n", ret);
449 		return -ENODEV;
450 	}
451 
452 	if (desc.version > 1) {
453 		dev_err(dev, "Protocol version %u is not supported\n", desc.version);
454 		return -ENODEV;
455 	}
456 
457 	gdrm = devm_drm_dev_alloc(dev, &gud_drm_driver, struct gud_device, drm);
458 	if (IS_ERR(gdrm))
459 		return PTR_ERR(gdrm);
460 
461 	drm = &gdrm->drm;
462 	drm->mode_config.funcs = &gud_mode_config_funcs;
463 	ret = drmm_mode_config_init(drm);
464 	if (ret)
465 		return ret;
466 
467 	gdrm->flags = le32_to_cpu(desc.flags);
468 	gdrm->compression = desc.compression & GUD_COMPRESSION_LZ4;
469 
470 	if (gdrm->flags & GUD_DISPLAY_FLAG_FULL_UPDATE && gdrm->compression)
471 		return -EINVAL;
472 
473 	mutex_init(&gdrm->ctrl_lock);
474 	mutex_init(&gdrm->damage_lock);
475 	INIT_WORK(&gdrm->work, gud_flush_work);
476 	gud_clear_damage(gdrm);
477 
478 	ret = devm_add_action(dev, gud_free_buffers_and_mutex, gdrm);
479 	if (ret)
480 		return ret;
481 
482 	drm->mode_config.min_width = le32_to_cpu(desc.min_width);
483 	drm->mode_config.max_width = le32_to_cpu(desc.max_width);
484 	drm->mode_config.min_height = le32_to_cpu(desc.min_height);
485 	drm->mode_config.max_height = le32_to_cpu(desc.max_height);
486 
487 	formats_dev = devm_kmalloc(dev, GUD_FORMATS_MAX_NUM, GFP_KERNEL);
488 	/* Add room for emulated XRGB8888 */
489 	formats = devm_kmalloc_array(dev, GUD_FORMATS_MAX_NUM + 1, sizeof(*formats), GFP_KERNEL);
490 	if (!formats_dev || !formats)
491 		return -ENOMEM;
492 
493 	ret = gud_usb_get(gdrm, GUD_REQ_GET_FORMATS, 0, formats_dev, GUD_FORMATS_MAX_NUM);
494 	if (ret < 0)
495 		return ret;
496 
497 	num_formats_dev = ret;
498 	for (i = 0; i < num_formats_dev; i++) {
499 		const struct drm_format_info *info;
500 		size_t fmt_buf_size;
501 		u32 format;
502 
503 		format = gud_to_fourcc(formats_dev[i]);
504 		if (!format) {
505 			drm_dbg(drm, "Unsupported format: 0x%02x\n", formats_dev[i]);
506 			continue;
507 		}
508 
509 		if (format == GUD_DRM_FORMAT_R1)
510 			info = &gud_drm_format_r1;
511 		else if (format == GUD_DRM_FORMAT_XRGB1111)
512 			info = &gud_drm_format_xrgb1111;
513 		else
514 			info = drm_format_info(format);
515 
516 		switch (format) {
517 		case GUD_DRM_FORMAT_R1:
518 			fallthrough;
519 		case DRM_FORMAT_R8:
520 			fallthrough;
521 		case GUD_DRM_FORMAT_XRGB1111:
522 			fallthrough;
523 		case DRM_FORMAT_RGB332:
524 			fallthrough;
525 		case DRM_FORMAT_RGB888:
526 			if (!xrgb8888_emulation_format)
527 				xrgb8888_emulation_format = info;
528 			break;
529 		case DRM_FORMAT_RGB565:
530 			rgb565_supported = true;
531 			if (!xrgb8888_emulation_format)
532 				xrgb8888_emulation_format = info;
533 			break;
534 		case DRM_FORMAT_XRGB8888:
535 			xrgb8888_supported = true;
536 			break;
537 		}
538 
539 		fmt_buf_size = drm_format_info_min_pitch(info, 0, drm->mode_config.max_width) *
540 			       drm->mode_config.max_height;
541 		max_buffer_size = max(max_buffer_size, fmt_buf_size);
542 
543 		if (format == GUD_DRM_FORMAT_R1 || format == GUD_DRM_FORMAT_XRGB1111)
544 			continue; /* Internal not for userspace */
545 
546 		formats[num_formats++] = format;
547 	}
548 
549 	if (!num_formats && !xrgb8888_emulation_format) {
550 		dev_err(dev, "No supported pixel formats found\n");
551 		return -EINVAL;
552 	}
553 
554 	/* Prefer speed over color depth */
555 	if (rgb565_supported)
556 		drm->mode_config.preferred_depth = 16;
557 
558 	if (!xrgb8888_supported && xrgb8888_emulation_format) {
559 		gdrm->xrgb8888_emulation_format = xrgb8888_emulation_format;
560 		formats[num_formats++] = DRM_FORMAT_XRGB8888;
561 	}
562 
563 	if (desc.max_buffer_size)
564 		max_buffer_size = le32_to_cpu(desc.max_buffer_size);
565 	/* Prevent a misbehaving device from allocating loads of RAM. 4096x4096@XRGB8888 = 64 MB */
566 	if (max_buffer_size > SZ_64M)
567 		max_buffer_size = SZ_64M;
568 
569 	gdrm->bulk_pipe = usb_sndbulkpipe(interface_to_usbdev(intf), usb_endpoint_num(bulk_out));
570 	gdrm->bulk_len = max_buffer_size;
571 
572 	ret = gud_alloc_bulk_buffer(gdrm);
573 	if (ret)
574 		return ret;
575 
576 	if (gdrm->compression & GUD_COMPRESSION_LZ4) {
577 		gdrm->lz4_comp_mem = devm_kmalloc(dev, LZ4_MEM_COMPRESS, GFP_KERNEL);
578 		if (!gdrm->lz4_comp_mem)
579 			return -ENOMEM;
580 
581 		gdrm->compress_buf = vmalloc(gdrm->bulk_len);
582 		if (!gdrm->compress_buf)
583 			return -ENOMEM;
584 	}
585 
586 	ret = drm_simple_display_pipe_init(drm, &gdrm->pipe, &gud_pipe_funcs,
587 					   formats, num_formats,
588 					   gud_pipe_modifiers, NULL);
589 	if (ret)
590 		return ret;
591 
592 	devm_kfree(dev, formats);
593 	devm_kfree(dev, formats_dev);
594 
595 	ret = gud_get_properties(gdrm);
596 	if (ret) {
597 		dev_err(dev, "Failed to get properties (error=%d)\n", ret);
598 		return ret;
599 	}
600 
601 	drm_plane_enable_fb_damage_clips(&gdrm->pipe.plane);
602 
603 	ret = gud_get_connectors(gdrm);
604 	if (ret) {
605 		dev_err(dev, "Failed to get connectors (error=%d)\n", ret);
606 		return ret;
607 	}
608 
609 	drm_mode_config_reset(drm);
610 
611 	usb_set_intfdata(intf, gdrm);
612 
613 	gdrm->dmadev = usb_intf_get_dma_device(intf);
614 	if (!gdrm->dmadev)
615 		dev_warn(dev, "buffer sharing not supported");
616 
617 	drm_debugfs_add_file(drm, "stats", gud_stats_debugfs, NULL);
618 
619 	ret = drm_dev_register(drm, 0);
620 	if (ret) {
621 		put_device(gdrm->dmadev);
622 		return ret;
623 	}
624 
625 	drm_kms_helper_poll_init(drm);
626 
627 	drm_client_setup(drm, NULL);
628 
629 	return 0;
630 }
631 
632 static void gud_disconnect(struct usb_interface *interface)
633 {
634 	struct gud_device *gdrm = usb_get_intfdata(interface);
635 	struct drm_device *drm = &gdrm->drm;
636 
637 	drm_dbg(drm, "%s:\n", __func__);
638 
639 	drm_kms_helper_poll_fini(drm);
640 	drm_dev_unplug(drm);
641 	drm_atomic_helper_shutdown(drm);
642 	put_device(gdrm->dmadev);
643 	gdrm->dmadev = NULL;
644 }
645 
646 static int gud_suspend(struct usb_interface *intf, pm_message_t message)
647 {
648 	struct gud_device *gdrm = usb_get_intfdata(intf);
649 
650 	return drm_mode_config_helper_suspend(&gdrm->drm);
651 }
652 
653 static int gud_resume(struct usb_interface *intf)
654 {
655 	struct gud_device *gdrm = usb_get_intfdata(intf);
656 
657 	drm_mode_config_helper_resume(&gdrm->drm);
658 
659 	return 0;
660 }
661 
662 static const struct usb_device_id gud_id_table[] = {
663 	{ USB_DEVICE_INTERFACE_CLASS(0x1d50, 0x614d, USB_CLASS_VENDOR_SPEC) },
664 	{ USB_DEVICE_INTERFACE_CLASS(0x16d0, 0x10a9, USB_CLASS_VENDOR_SPEC) },
665 	{ }
666 };
667 
668 MODULE_DEVICE_TABLE(usb, gud_id_table);
669 
670 static struct usb_driver gud_usb_driver = {
671 	.name		= "gud",
672 	.probe		= gud_probe,
673 	.disconnect	= gud_disconnect,
674 	.id_table	= gud_id_table,
675 	.suspend	= gud_suspend,
676 	.resume		= gud_resume,
677 	.reset_resume	= gud_resume,
678 };
679 
680 module_usb_driver(gud_usb_driver);
681 
682 MODULE_AUTHOR("Noralf Trønnes");
683 MODULE_DESCRIPTION("GUD USB Display driver");
684 MODULE_LICENSE("Dual MIT/GPL");
685