xref: /openbmc/linux/drivers/gpu/drm/drm_fourcc.c (revision 5b4cb650)
1 /*
2  * Copyright (c) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
3  *
4  * DRM core format related functions
5  *
6  * Permission to use, copy, modify, distribute, and sell this software and its
7  * documentation for any purpose is hereby granted without fee, provided that
8  * the above copyright notice appear in all copies and that both that copyright
9  * notice and this permission notice appear in supporting documentation, and
10  * that the name of the copyright holders not be used in advertising or
11  * publicity pertaining to distribution of the software without specific,
12  * written prior permission.  The copyright holders make no representations
13  * about the suitability of this software for any purpose.  It is provided "as
14  * is" without express or implied warranty.
15  *
16  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
17  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
18  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
19  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
20  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
21  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
22  * OF THIS SOFTWARE.
23  */
24 
25 #include <linux/bug.h>
26 #include <linux/ctype.h>
27 #include <linux/export.h>
28 #include <linux/kernel.h>
29 
30 #include <drm/drmP.h>
31 #include <drm/drm_fourcc.h>
32 
33 static char printable_char(int c)
34 {
35 	return isascii(c) && isprint(c) ? c : '?';
36 }
37 
38 /**
39  * drm_mode_legacy_fb_format - compute drm fourcc code from legacy description
40  * @bpp: bits per pixels
41  * @depth: bit depth per pixel
42  *
43  * Computes a drm fourcc pixel format code for the given @bpp/@depth values.
44  * Useful in fbdev emulation code, since that deals in those values.
45  */
46 uint32_t drm_mode_legacy_fb_format(uint32_t bpp, uint32_t depth)
47 {
48 	uint32_t fmt = DRM_FORMAT_INVALID;
49 
50 	switch (bpp) {
51 	case 8:
52 		if (depth == 8)
53 			fmt = DRM_FORMAT_C8;
54 		break;
55 
56 	case 16:
57 		switch (depth) {
58 		case 15:
59 			fmt = DRM_FORMAT_XRGB1555;
60 			break;
61 		case 16:
62 			fmt = DRM_FORMAT_RGB565;
63 			break;
64 		default:
65 			break;
66 		}
67 		break;
68 
69 	case 24:
70 		if (depth == 24)
71 			fmt = DRM_FORMAT_RGB888;
72 		break;
73 
74 	case 32:
75 		switch (depth) {
76 		case 24:
77 			fmt = DRM_FORMAT_XRGB8888;
78 			break;
79 		case 30:
80 			fmt = DRM_FORMAT_XRGB2101010;
81 			break;
82 		case 32:
83 			fmt = DRM_FORMAT_ARGB8888;
84 			break;
85 		default:
86 			break;
87 		}
88 		break;
89 
90 	default:
91 		break;
92 	}
93 
94 	return fmt;
95 }
96 EXPORT_SYMBOL(drm_mode_legacy_fb_format);
97 
98 /**
99  * drm_driver_legacy_fb_format - compute drm fourcc code from legacy description
100  * @dev: DRM device
101  * @bpp: bits per pixels
102  * @depth: bit depth per pixel
103  *
104  * Computes a drm fourcc pixel format code for the given @bpp/@depth values.
105  * Unlike drm_mode_legacy_fb_format() this looks at the drivers mode_config,
106  * and depending on the &drm_mode_config.quirk_addfb_prefer_host_byte_order flag
107  * it returns little endian byte order or host byte order framebuffer formats.
108  */
109 uint32_t drm_driver_legacy_fb_format(struct drm_device *dev,
110 				     uint32_t bpp, uint32_t depth)
111 {
112 	uint32_t fmt = drm_mode_legacy_fb_format(bpp, depth);
113 
114 	if (dev->mode_config.quirk_addfb_prefer_host_byte_order) {
115 		if (fmt == DRM_FORMAT_XRGB8888)
116 			fmt = DRM_FORMAT_HOST_XRGB8888;
117 		if (fmt == DRM_FORMAT_ARGB8888)
118 			fmt = DRM_FORMAT_HOST_ARGB8888;
119 		if (fmt == DRM_FORMAT_RGB565)
120 			fmt = DRM_FORMAT_HOST_RGB565;
121 		if (fmt == DRM_FORMAT_XRGB1555)
122 			fmt = DRM_FORMAT_HOST_XRGB1555;
123 	}
124 
125 	if (dev->mode_config.quirk_addfb_prefer_xbgr_30bpp &&
126 	    fmt == DRM_FORMAT_XRGB2101010)
127 		fmt = DRM_FORMAT_XBGR2101010;
128 
129 	return fmt;
130 }
131 EXPORT_SYMBOL(drm_driver_legacy_fb_format);
132 
133 /**
134  * drm_get_format_name - fill a string with a drm fourcc format's name
135  * @format: format to compute name of
136  * @buf: caller-supplied buffer
137  */
138 const char *drm_get_format_name(uint32_t format, struct drm_format_name_buf *buf)
139 {
140 	snprintf(buf->str, sizeof(buf->str),
141 		 "%c%c%c%c %s-endian (0x%08x)",
142 		 printable_char(format & 0xff),
143 		 printable_char((format >> 8) & 0xff),
144 		 printable_char((format >> 16) & 0xff),
145 		 printable_char((format >> 24) & 0x7f),
146 		 format & DRM_FORMAT_BIG_ENDIAN ? "big" : "little",
147 		 format);
148 
149 	return buf->str;
150 }
151 EXPORT_SYMBOL(drm_get_format_name);
152 
153 /*
154  * Internal function to query information for a given format. See
155  * drm_format_info() for the public API.
156  */
157 const struct drm_format_info *__drm_format_info(u32 format)
158 {
159 	static const struct drm_format_info formats[] = {
160 		{ .format = DRM_FORMAT_C8,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
161 		{ .format = DRM_FORMAT_RGB332,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
162 		{ .format = DRM_FORMAT_BGR233,		.depth = 8,  .num_planes = 1, .cpp = { 1, 0, 0 }, .hsub = 1, .vsub = 1 },
163 		{ .format = DRM_FORMAT_XRGB4444,	.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
164 		{ .format = DRM_FORMAT_XBGR4444,	.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
165 		{ .format = DRM_FORMAT_RGBX4444,	.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
166 		{ .format = DRM_FORMAT_BGRX4444,	.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
167 		{ .format = DRM_FORMAT_ARGB4444,	.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
168 		{ .format = DRM_FORMAT_ABGR4444,	.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
169 		{ .format = DRM_FORMAT_RGBA4444,	.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
170 		{ .format = DRM_FORMAT_BGRA4444,	.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
171 		{ .format = DRM_FORMAT_XRGB1555,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
172 		{ .format = DRM_FORMAT_XBGR1555,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
173 		{ .format = DRM_FORMAT_RGBX5551,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
174 		{ .format = DRM_FORMAT_BGRX5551,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
175 		{ .format = DRM_FORMAT_ARGB1555,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
176 		{ .format = DRM_FORMAT_ABGR1555,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
177 		{ .format = DRM_FORMAT_RGBA5551,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
178 		{ .format = DRM_FORMAT_BGRA5551,	.depth = 15, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
179 		{ .format = DRM_FORMAT_RGB565,		.depth = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
180 		{ .format = DRM_FORMAT_BGR565,		.depth = 16, .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 1, .vsub = 1 },
181 		{ .format = DRM_FORMAT_RGB888,		.depth = 24, .num_planes = 1, .cpp = { 3, 0, 0 }, .hsub = 1, .vsub = 1 },
182 		{ .format = DRM_FORMAT_BGR888,		.depth = 24, .num_planes = 1, .cpp = { 3, 0, 0 }, .hsub = 1, .vsub = 1 },
183 		{ .format = DRM_FORMAT_XRGB8888,	.depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
184 		{ .format = DRM_FORMAT_XBGR8888,	.depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
185 		{ .format = DRM_FORMAT_RGBX8888,	.depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
186 		{ .format = DRM_FORMAT_BGRX8888,	.depth = 24, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
187 		{ .format = DRM_FORMAT_RGB565_A8,	.depth = 24, .num_planes = 2, .cpp = { 2, 1, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
188 		{ .format = DRM_FORMAT_BGR565_A8,	.depth = 24, .num_planes = 2, .cpp = { 2, 1, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
189 		{ .format = DRM_FORMAT_XRGB2101010,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
190 		{ .format = DRM_FORMAT_XBGR2101010,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
191 		{ .format = DRM_FORMAT_RGBX1010102,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
192 		{ .format = DRM_FORMAT_BGRX1010102,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1 },
193 		{ .format = DRM_FORMAT_ARGB2101010,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
194 		{ .format = DRM_FORMAT_ABGR2101010,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
195 		{ .format = DRM_FORMAT_RGBA1010102,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
196 		{ .format = DRM_FORMAT_BGRA1010102,	.depth = 30, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
197 		{ .format = DRM_FORMAT_ARGB8888,	.depth = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
198 		{ .format = DRM_FORMAT_ABGR8888,	.depth = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
199 		{ .format = DRM_FORMAT_RGBA8888,	.depth = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
200 		{ .format = DRM_FORMAT_BGRA8888,	.depth = 32, .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
201 		{ .format = DRM_FORMAT_RGB888_A8,	.depth = 32, .num_planes = 2, .cpp = { 3, 1, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
202 		{ .format = DRM_FORMAT_BGR888_A8,	.depth = 32, .num_planes = 2, .cpp = { 3, 1, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
203 		{ .format = DRM_FORMAT_XRGB8888_A8,	.depth = 32, .num_planes = 2, .cpp = { 4, 1, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
204 		{ .format = DRM_FORMAT_XBGR8888_A8,	.depth = 32, .num_planes = 2, .cpp = { 4, 1, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
205 		{ .format = DRM_FORMAT_RGBX8888_A8,	.depth = 32, .num_planes = 2, .cpp = { 4, 1, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
206 		{ .format = DRM_FORMAT_BGRX8888_A8,	.depth = 32, .num_planes = 2, .cpp = { 4, 1, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true },
207 		{ .format = DRM_FORMAT_YUV410,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 4, .is_yuv = true },
208 		{ .format = DRM_FORMAT_YVU410,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 4, .is_yuv = true },
209 		{ .format = DRM_FORMAT_YUV411,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 1, .is_yuv = true },
210 		{ .format = DRM_FORMAT_YVU411,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 4, .vsub = 1, .is_yuv = true },
211 		{ .format = DRM_FORMAT_YUV420,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 2, .is_yuv = true },
212 		{ .format = DRM_FORMAT_YVU420,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 2, .is_yuv = true },
213 		{ .format = DRM_FORMAT_YUV422,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 1, .is_yuv = true },
214 		{ .format = DRM_FORMAT_YVU422,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 2, .vsub = 1, .is_yuv = true },
215 		{ .format = DRM_FORMAT_YUV444,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 1, .vsub = 1, .is_yuv = true },
216 		{ .format = DRM_FORMAT_YVU444,		.depth = 0,  .num_planes = 3, .cpp = { 1, 1, 1 }, .hsub = 1, .vsub = 1, .is_yuv = true },
217 		{ .format = DRM_FORMAT_NV12,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 2, .is_yuv = true },
218 		{ .format = DRM_FORMAT_NV21,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 2, .is_yuv = true },
219 		{ .format = DRM_FORMAT_NV16,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 1, .is_yuv = true },
220 		{ .format = DRM_FORMAT_NV61,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 2, .vsub = 1, .is_yuv = true },
221 		{ .format = DRM_FORMAT_NV24,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 1, .vsub = 1, .is_yuv = true },
222 		{ .format = DRM_FORMAT_NV42,		.depth = 0,  .num_planes = 2, .cpp = { 1, 2, 0 }, .hsub = 1, .vsub = 1, .is_yuv = true },
223 		{ .format = DRM_FORMAT_YUYV,		.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1, .is_yuv = true },
224 		{ .format = DRM_FORMAT_YVYU,		.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1, .is_yuv = true },
225 		{ .format = DRM_FORMAT_UYVY,		.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1, .is_yuv = true },
226 		{ .format = DRM_FORMAT_VYUY,		.depth = 0,  .num_planes = 1, .cpp = { 2, 0, 0 }, .hsub = 2, .vsub = 1, .is_yuv = true },
227 		{ .format = DRM_FORMAT_XYUV8888,	.depth = 0,  .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .is_yuv = true },
228 		{ .format = DRM_FORMAT_AYUV,		.depth = 0,  .num_planes = 1, .cpp = { 4, 0, 0 }, .hsub = 1, .vsub = 1, .has_alpha = true, .is_yuv = true },
229 		{ .format = DRM_FORMAT_Y0L0,		.depth = 0,  .num_planes = 1,
230 		  .char_per_block = { 8, 0, 0 }, .block_w = { 2, 0, 0 }, .block_h = { 2, 0, 0 },
231 		  .hsub = 2, .vsub = 2, .has_alpha = true, .is_yuv = true },
232 		{ .format = DRM_FORMAT_X0L0,		.depth = 0,  .num_planes = 1,
233 		  .char_per_block = { 8, 0, 0 }, .block_w = { 2, 0, 0 }, .block_h = { 2, 0, 0 },
234 		  .hsub = 2, .vsub = 2, .is_yuv = true },
235 		{ .format = DRM_FORMAT_Y0L2,		.depth = 0,  .num_planes = 1,
236 		  .char_per_block = { 8, 0, 0 }, .block_w = { 2, 0, 0 }, .block_h = { 2, 0, 0 },
237 		  .hsub = 2, .vsub = 2, .has_alpha = true, .is_yuv = true },
238 		{ .format = DRM_FORMAT_X0L2,		.depth = 0,  .num_planes = 1,
239 		  .char_per_block = { 8, 0, 0 }, .block_w = { 2, 0, 0 }, .block_h = { 2, 0, 0 },
240 		  .hsub = 2, .vsub = 2, .is_yuv = true },
241 	};
242 
243 	unsigned int i;
244 
245 	for (i = 0; i < ARRAY_SIZE(formats); ++i) {
246 		if (formats[i].format == format)
247 			return &formats[i];
248 	}
249 
250 	return NULL;
251 }
252 
253 /**
254  * drm_format_info - query information for a given format
255  * @format: pixel format (DRM_FORMAT_*)
256  *
257  * The caller should only pass a supported pixel format to this function.
258  * Unsupported pixel formats will generate a warning in the kernel log.
259  *
260  * Returns:
261  * The instance of struct drm_format_info that describes the pixel format, or
262  * NULL if the format is unsupported.
263  */
264 const struct drm_format_info *drm_format_info(u32 format)
265 {
266 	const struct drm_format_info *info;
267 
268 	info = __drm_format_info(format);
269 	WARN_ON(!info);
270 	return info;
271 }
272 EXPORT_SYMBOL(drm_format_info);
273 
274 /**
275  * drm_get_format_info - query information for a given framebuffer configuration
276  * @dev: DRM device
277  * @mode_cmd: metadata from the userspace fb creation request
278  *
279  * Returns:
280  * The instance of struct drm_format_info that describes the pixel format, or
281  * NULL if the format is unsupported.
282  */
283 const struct drm_format_info *
284 drm_get_format_info(struct drm_device *dev,
285 		    const struct drm_mode_fb_cmd2 *mode_cmd)
286 {
287 	const struct drm_format_info *info = NULL;
288 
289 	if (dev->mode_config.funcs->get_format_info)
290 		info = dev->mode_config.funcs->get_format_info(mode_cmd);
291 
292 	if (!info)
293 		info = drm_format_info(mode_cmd->pixel_format);
294 
295 	return info;
296 }
297 EXPORT_SYMBOL(drm_get_format_info);
298 
299 /**
300  * drm_format_num_planes - get the number of planes for format
301  * @format: pixel format (DRM_FORMAT_*)
302  *
303  * Returns:
304  * The number of planes used by the specified pixel format.
305  */
306 int drm_format_num_planes(uint32_t format)
307 {
308 	const struct drm_format_info *info;
309 
310 	info = drm_format_info(format);
311 	return info ? info->num_planes : 1;
312 }
313 EXPORT_SYMBOL(drm_format_num_planes);
314 
315 /**
316  * drm_format_plane_cpp - determine the bytes per pixel value
317  * @format: pixel format (DRM_FORMAT_*)
318  * @plane: plane index
319  *
320  * Returns:
321  * The bytes per pixel value for the specified plane.
322  */
323 int drm_format_plane_cpp(uint32_t format, int plane)
324 {
325 	const struct drm_format_info *info;
326 
327 	info = drm_format_info(format);
328 	if (!info || plane >= info->num_planes)
329 		return 0;
330 
331 	return info->cpp[plane];
332 }
333 EXPORT_SYMBOL(drm_format_plane_cpp);
334 
335 /**
336  * drm_format_horz_chroma_subsampling - get the horizontal chroma subsampling factor
337  * @format: pixel format (DRM_FORMAT_*)
338  *
339  * Returns:
340  * The horizontal chroma subsampling factor for the
341  * specified pixel format.
342  */
343 int drm_format_horz_chroma_subsampling(uint32_t format)
344 {
345 	const struct drm_format_info *info;
346 
347 	info = drm_format_info(format);
348 	return info ? info->hsub : 1;
349 }
350 EXPORT_SYMBOL(drm_format_horz_chroma_subsampling);
351 
352 /**
353  * drm_format_vert_chroma_subsampling - get the vertical chroma subsampling factor
354  * @format: pixel format (DRM_FORMAT_*)
355  *
356  * Returns:
357  * The vertical chroma subsampling factor for the
358  * specified pixel format.
359  */
360 int drm_format_vert_chroma_subsampling(uint32_t format)
361 {
362 	const struct drm_format_info *info;
363 
364 	info = drm_format_info(format);
365 	return info ? info->vsub : 1;
366 }
367 EXPORT_SYMBOL(drm_format_vert_chroma_subsampling);
368 
369 /**
370  * drm_format_plane_width - width of the plane given the first plane
371  * @width: width of the first plane
372  * @format: pixel format
373  * @plane: plane index
374  *
375  * Returns:
376  * The width of @plane, given that the width of the first plane is @width.
377  */
378 int drm_format_plane_width(int width, uint32_t format, int plane)
379 {
380 	const struct drm_format_info *info;
381 
382 	info = drm_format_info(format);
383 	if (!info || plane >= info->num_planes)
384 		return 0;
385 
386 	if (plane == 0)
387 		return width;
388 
389 	return width / info->hsub;
390 }
391 EXPORT_SYMBOL(drm_format_plane_width);
392 
393 /**
394  * drm_format_plane_height - height of the plane given the first plane
395  * @height: height of the first plane
396  * @format: pixel format
397  * @plane: plane index
398  *
399  * Returns:
400  * The height of @plane, given that the height of the first plane is @height.
401  */
402 int drm_format_plane_height(int height, uint32_t format, int plane)
403 {
404 	const struct drm_format_info *info;
405 
406 	info = drm_format_info(format);
407 	if (!info || plane >= info->num_planes)
408 		return 0;
409 
410 	if (plane == 0)
411 		return height;
412 
413 	return height / info->vsub;
414 }
415 EXPORT_SYMBOL(drm_format_plane_height);
416 
417 /**
418  * drm_format_info_block_width - width in pixels of block.
419  * @info: pixel format info
420  * @plane: plane index
421  *
422  * Returns:
423  * The width in pixels of a block, depending on the plane index.
424  */
425 unsigned int drm_format_info_block_width(const struct drm_format_info *info,
426 					 int plane)
427 {
428 	if (!info || plane < 0 || plane >= info->num_planes)
429 		return 0;
430 
431 	if (!info->block_w[plane])
432 		return 1;
433 	return info->block_w[plane];
434 }
435 EXPORT_SYMBOL(drm_format_info_block_width);
436 
437 /**
438  * drm_format_info_block_height - height in pixels of a block
439  * @info: pixel format info
440  * @plane: plane index
441  *
442  * Returns:
443  * The height in pixels of a block, depending on the plane index.
444  */
445 unsigned int drm_format_info_block_height(const struct drm_format_info *info,
446 					  int plane)
447 {
448 	if (!info || plane < 0 || plane >= info->num_planes)
449 		return 0;
450 
451 	if (!info->block_h[plane])
452 		return 1;
453 	return info->block_h[plane];
454 }
455 EXPORT_SYMBOL(drm_format_info_block_height);
456 
457 /**
458  * drm_format_info_min_pitch - computes the minimum required pitch in bytes
459  * @info: pixel format info
460  * @plane: plane index
461  * @buffer_width: buffer width in pixels
462  *
463  * Returns:
464  * The minimum required pitch in bytes for a buffer by taking into consideration
465  * the pixel format information and the buffer width.
466  */
467 uint64_t drm_format_info_min_pitch(const struct drm_format_info *info,
468 				   int plane, unsigned int buffer_width)
469 {
470 	if (!info || plane < 0 || plane >= info->num_planes)
471 		return 0;
472 
473 	return DIV_ROUND_UP_ULL((u64)buffer_width * info->char_per_block[plane],
474 			    drm_format_info_block_width(info, plane) *
475 			    drm_format_info_block_height(info, plane));
476 }
477 EXPORT_SYMBOL(drm_format_info_min_pitch);
478