video: of: display_timing: add doubleclk flag
[linux-2.6-block.git] / drivers / video / of_display_timing.c
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cc3f414c
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1/*
2 * OF helpers for parsing display timings
3 *
4 * Copyright (c) 2012 Steffen Trumtrar <s.trumtrar@pengutronix.de>, Pengutronix
5 *
6 * based on of_videomode.c by Sascha Hauer <s.hauer@pengutronix.de>
7 *
8 * This file is released under the GPLv2
9 */
10#include <linux/export.h>
11#include <linux/of.h>
12#include <linux/slab.h>
13#include <video/display_timing.h>
14#include <video/of_display_timing.h>
15
16/**
17 * parse_timing_property - parse timing_entry from device_node
18 * @np: device_node with the property
19 * @name: name of the property
20 * @result: will be set to the return value
21 *
22 * DESCRIPTION:
23 * Every display_timing can be specified with either just the typical value or
24 * a range consisting of min/typ/max. This function helps handling this
25 **/
f5836623 26static int parse_timing_property(const struct device_node *np, const char *name,
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27 struct timing_entry *result)
28{
29 struct property *prop;
30 int length, cells, ret;
31
32 prop = of_find_property(np, name, &length);
33 if (!prop) {
34 pr_err("%s: could not find property %s\n",
35 of_node_full_name(np), name);
36 return -EINVAL;
37 }
38
39 cells = length / sizeof(u32);
40 if (cells == 1) {
41 ret = of_property_read_u32(np, name, &result->typ);
42 result->min = result->typ;
43 result->max = result->typ;
44 } else if (cells == 3) {
45 ret = of_property_read_u32_array(np, name, &result->min, cells);
46 } else {
47 pr_err("%s: illegal timing specification in %s\n",
48 of_node_full_name(np), name);
49 return -EINVAL;
50 }
51
52 return ret;
53}
54
55/**
56 * of_get_display_timing - parse display_timing entry from device_node
57 * @np: device_node with the properties
58 **/
f5836623
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59static struct display_timing *of_get_display_timing(const struct device_node
60 *np)
cc3f414c
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61{
62 struct display_timing *dt;
63 u32 val = 0;
64 int ret = 0;
65
66 dt = kzalloc(sizeof(*dt), GFP_KERNEL);
67 if (!dt) {
68 pr_err("%s: could not allocate display_timing struct\n",
69 of_node_full_name(np));
70 return NULL;
71 }
72
73 ret |= parse_timing_property(np, "hback-porch", &dt->hback_porch);
74 ret |= parse_timing_property(np, "hfront-porch", &dt->hfront_porch);
75 ret |= parse_timing_property(np, "hactive", &dt->hactive);
76 ret |= parse_timing_property(np, "hsync-len", &dt->hsync_len);
77 ret |= parse_timing_property(np, "vback-porch", &dt->vback_porch);
78 ret |= parse_timing_property(np, "vfront-porch", &dt->vfront_porch);
79 ret |= parse_timing_property(np, "vactive", &dt->vactive);
80 ret |= parse_timing_property(np, "vsync-len", &dt->vsync_len);
81 ret |= parse_timing_property(np, "clock-frequency", &dt->pixelclock);
82
06a33079 83 dt->flags = 0;
cc3f414c 84 if (!of_property_read_u32(np, "vsync-active", &val))
06a33079
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85 dt->flags |= val ? DISPLAY_FLAGS_VSYNC_HIGH :
86 DISPLAY_FLAGS_VSYNC_LOW;
cc3f414c 87 if (!of_property_read_u32(np, "hsync-active", &val))
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88 dt->flags |= val ? DISPLAY_FLAGS_HSYNC_HIGH :
89 DISPLAY_FLAGS_HSYNC_LOW;
cc3f414c 90 if (!of_property_read_u32(np, "de-active", &val))
06a33079 91 dt->flags |= val ? DISPLAY_FLAGS_DE_HIGH :
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92 DISPLAY_FLAGS_DE_LOW;
93 if (!of_property_read_u32(np, "pixelclk-active", &val))
06a33079 94 dt->flags |= val ? DISPLAY_FLAGS_PIXDATA_POSEDGE :
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95 DISPLAY_FLAGS_PIXDATA_NEGEDGE;
96
97 if (of_property_read_bool(np, "interlaced"))
06a33079 98 dt->flags |= DISPLAY_FLAGS_INTERLACED;
cc3f414c 99 if (of_property_read_bool(np, "doublescan"))
06a33079 100 dt->flags |= DISPLAY_FLAGS_DOUBLESCAN;
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101 if (of_property_read_bool(np, "doubleclk"))
102 dt->flags |= DISPLAY_FLAGS_DOUBLECLK;
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103
104 if (ret) {
105 pr_err("%s: error reading timing properties\n",
106 of_node_full_name(np));
107 kfree(dt);
108 return NULL;
109 }
110
111 return dt;
112}
113
114/**
115 * of_get_display_timings - parse all display_timing entries from a device_node
116 * @np: device_node with the subnodes
117 **/
118struct display_timings *of_get_display_timings(struct device_node *np)
119{
120 struct device_node *timings_np;
121 struct device_node *entry;
122 struct device_node *native_mode;
123 struct display_timings *disp;
124
125 if (!np) {
126 pr_err("%s: no devicenode given\n", of_node_full_name(np));
127 return NULL;
128 }
129
130 timings_np = of_find_node_by_name(np, "display-timings");
131 if (!timings_np) {
132 pr_err("%s: could not find display-timings node\n",
133 of_node_full_name(np));
134 return NULL;
135 }
136
137 disp = kzalloc(sizeof(*disp), GFP_KERNEL);
138 if (!disp) {
139 pr_err("%s: could not allocate struct disp'\n",
140 of_node_full_name(np));
141 goto dispfail;
142 }
143
144 entry = of_parse_phandle(timings_np, "native-mode", 0);
145 /* assume first child as native mode if none provided */
146 if (!entry)
147 entry = of_get_next_child(np, NULL);
148 /* if there is no child, it is useless to go on */
149 if (!entry) {
150 pr_err("%s: no timing specifications given\n",
151 of_node_full_name(np));
152 goto entryfail;
153 }
154
155 pr_debug("%s: using %s as default timing\n",
156 of_node_full_name(np), entry->name);
157
158 native_mode = entry;
159
160 disp->num_timings = of_get_child_count(timings_np);
161 if (disp->num_timings == 0) {
162 /* should never happen, as entry was already found above */
163 pr_err("%s: no timings specified\n", of_node_full_name(np));
164 goto entryfail;
165 }
166
167 disp->timings = kzalloc(sizeof(struct display_timing *) *
168 disp->num_timings, GFP_KERNEL);
169 if (!disp->timings) {
170 pr_err("%s: could not allocate timings array\n",
171 of_node_full_name(np));
172 goto entryfail;
173 }
174
175 disp->num_timings = 0;
176 disp->native_mode = 0;
177
178 for_each_child_of_node(timings_np, entry) {
179 struct display_timing *dt;
180
181 dt = of_get_display_timing(entry);
182 if (!dt) {
183 /*
184 * to not encourage wrong devicetrees, fail in case of
185 * an error
186 */
187 pr_err("%s: error in timing %d\n",
188 of_node_full_name(np), disp->num_timings + 1);
189 goto timingfail;
190 }
191
192 if (native_mode == entry)
193 disp->native_mode = disp->num_timings;
194
195 disp->timings[disp->num_timings] = dt;
196 disp->num_timings++;
197 }
198 of_node_put(timings_np);
199 /*
200 * native_mode points to the device_node returned by of_parse_phandle
201 * therefore call of_node_put on it
202 */
203 of_node_put(native_mode);
204
205 pr_debug("%s: got %d timings. Using timing #%d as default\n",
206 of_node_full_name(np), disp->num_timings,
207 disp->native_mode + 1);
208
209 return disp;
210
211timingfail:
212 if (native_mode)
213 of_node_put(native_mode);
214 display_timings_release(disp);
215entryfail:
216 kfree(disp);
217dispfail:
218 of_node_put(timings_np);
219 return NULL;
220}
221EXPORT_SYMBOL_GPL(of_get_display_timings);
222
223/**
224 * of_display_timings_exist - check if a display-timings node is provided
225 * @np: device_node with the timing
226 **/
227int of_display_timings_exist(struct device_node *np)
228{
229 struct device_node *timings_np;
230
231 if (!np)
232 return -EINVAL;
233
234 timings_np = of_parse_phandle(np, "display-timings", 0);
235 if (!timings_np)
236 return -EINVAL;
237
238 of_node_put(timings_np);
239 return 1;
240}
241EXPORT_SYMBOL_GPL(of_display_timings_exist);