1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Panel driver for the ARM Versatile family reference designs from |
4 | * ARM Limited. |
5 | * |
6 | * Author: |
7 | * Linus Walleij <linus.wallei@linaro.org> |
8 | * |
9 | * On the Versatile AB, these panels come mounted on daughterboards |
10 | * named "IB1" or "IB2" (Interface Board 1 & 2 respectively.) They |
11 | * are documented in ARM DUI 0225D Appendix C and D. These daughter |
12 | * boards support TFT display panels. |
13 | * |
14 | * - The IB1 is a passive board where the display connector defines a |
15 | * few wires for encoding the display type for autodetection, |
16 | * suitable display settings can then be looked up from this setting. |
17 | * The magic bits can be read out from the system controller. |
18 | * |
19 | * - The IB2 is a more complex board intended for GSM phone development |
20 | * with some logic and a control register, which needs to be accessed |
21 | * and the board display needs to be turned on explicitly. |
22 | * |
23 | * On the Versatile PB, a special CLCD adaptor board is available |
24 | * supporting the same displays as the Versatile AB, plus one more |
25 | * Epson QCIF display. |
26 | * |
27 | */ |
28 | |
29 | #include <linux/bitops.h> |
30 | #include <linux/init.h> |
31 | #include <linux/kernel.h> |
32 | #include <linux/mfd/syscon.h> |
33 | #include <linux/mod_devicetable.h> |
34 | #include <linux/module.h> |
35 | #include <linux/platform_device.h> |
36 | #include <linux/regmap.h> |
37 | |
38 | #include <video/of_videomode.h> |
39 | #include <video/videomode.h> |
40 | |
41 | #include <drm/drm_modes.h> |
42 | #include <drm/drm_panel.h> |
43 | |
44 | /* |
45 | * This configuration register in the Versatile and RealView |
46 | * family is uniformly present but appears more and more |
47 | * unutilized starting with the RealView series. |
48 | */ |
49 | #define SYS_CLCD 0x50 |
50 | |
51 | /* The Versatile can detect the connected panel type */ |
52 | #define SYS_CLCD_CLCDID_MASK (BIT(8)|BIT(9)|BIT(10)|BIT(11)|BIT(12)) |
53 | #define SYS_CLCD_ID_SANYO_3_8 (0x00 << 8) |
54 | #define SYS_CLCD_ID_SHARP_8_4 (0x01 << 8) |
55 | #define SYS_CLCD_ID_EPSON_2_2 (0x02 << 8) |
56 | #define SYS_CLCD_ID_SANYO_2_5 (0x07 << 8) |
57 | #define SYS_CLCD_ID_VGA (0x1f << 8) |
58 | |
59 | /* IB2 control register for the Versatile daughterboard */ |
60 | #define IB2_CTRL 0x00 |
61 | #define IB2_CTRL_LCD_SD BIT(1) /* 1 = shut down LCD */ |
62 | #define IB2_CTRL_LCD_BL_ON BIT(0) |
63 | #define IB2_CTRL_LCD_MASK (BIT(0)|BIT(1)) |
64 | |
65 | /** |
66 | * struct versatile_panel_type - lookup struct for the supported panels |
67 | */ |
68 | struct versatile_panel_type { |
69 | /** |
70 | * @name: the name of this panel |
71 | */ |
72 | const char *name; |
73 | /** |
74 | * @magic: the magic value from the detection register |
75 | */ |
76 | u32 magic; |
77 | /** |
78 | * @mode: the DRM display mode for this panel |
79 | */ |
80 | struct drm_display_mode mode; |
81 | /** |
82 | * @bus_flags: the DRM bus flags for this panel e.g. inverted clock |
83 | */ |
84 | u32 bus_flags; |
85 | /** |
86 | * @width_mm: the panel width in mm |
87 | */ |
88 | u32 width_mm; |
89 | /** |
90 | * @height_mm: the panel height in mm |
91 | */ |
92 | u32 height_mm; |
93 | /** |
94 | * @ib2: the panel may be connected on an IB2 daughterboard |
95 | */ |
96 | bool ib2; |
97 | }; |
98 | |
99 | /** |
100 | * struct versatile_panel - state container for the Versatile panels |
101 | */ |
102 | struct versatile_panel { |
103 | /** |
104 | * @dev: the container device |
105 | */ |
106 | struct device *dev; |
107 | /** |
108 | * @panel: the DRM panel instance for this device |
109 | */ |
110 | struct drm_panel panel; |
111 | /** |
112 | * @panel_type: the Versatile panel type as detected |
113 | */ |
114 | const struct versatile_panel_type *panel_type; |
115 | /** |
116 | * @map: map to the parent syscon where the main register reside |
117 | */ |
118 | struct regmap *map; |
119 | /** |
120 | * @ib2_map: map to the IB2 syscon, if applicable |
121 | */ |
122 | struct regmap *ib2_map; |
123 | }; |
124 | |
125 | static const struct versatile_panel_type versatile_panels[] = { |
126 | /* |
127 | * Sanyo TM38QV67A02A - 3.8 inch QVGA (320x240) Color TFT |
128 | * found on the Versatile AB IB1 connector or the Versatile |
129 | * PB adaptor board connector. |
130 | */ |
131 | { |
132 | .name = "Sanyo TM38QV67A02A" , |
133 | .magic = SYS_CLCD_ID_SANYO_3_8, |
134 | .width_mm = 79, |
135 | .height_mm = 54, |
136 | .mode = { |
137 | .clock = 10000, |
138 | .hdisplay = 320, |
139 | .hsync_start = 320 + 6, |
140 | .hsync_end = 320 + 6 + 6, |
141 | .htotal = 320 + 6 + 6 + 6, |
142 | .vdisplay = 240, |
143 | .vsync_start = 240 + 5, |
144 | .vsync_end = 240 + 5 + 6, |
145 | .vtotal = 240 + 5 + 6 + 5, |
146 | .flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC, |
147 | }, |
148 | }, |
149 | /* |
150 | * Sharp LQ084V1DG21 640x480 VGA Color TFT module |
151 | * found on the Versatile AB IB1 connector or the Versatile |
152 | * PB adaptor board connector. |
153 | */ |
154 | { |
155 | .name = "Sharp LQ084V1DG21" , |
156 | .magic = SYS_CLCD_ID_SHARP_8_4, |
157 | .width_mm = 171, |
158 | .height_mm = 130, |
159 | .mode = { |
160 | .clock = 25000, |
161 | .hdisplay = 640, |
162 | .hsync_start = 640 + 24, |
163 | .hsync_end = 640 + 24 + 96, |
164 | .htotal = 640 + 24 + 96 + 24, |
165 | .vdisplay = 480, |
166 | .vsync_start = 480 + 11, |
167 | .vsync_end = 480 + 11 + 2, |
168 | .vtotal = 480 + 11 + 2 + 32, |
169 | .flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC, |
170 | }, |
171 | }, |
172 | /* |
173 | * Epson L2F50113T00 - 2.2 inch QCIF 176x220 Color TFT |
174 | * found on the Versatile PB adaptor board connector. |
175 | */ |
176 | { |
177 | .name = "Epson L2F50113T00" , |
178 | .magic = SYS_CLCD_ID_EPSON_2_2, |
179 | .width_mm = 34, |
180 | .height_mm = 45, |
181 | .mode = { |
182 | .clock = 62500, |
183 | .hdisplay = 176, |
184 | .hsync_start = 176 + 2, |
185 | .hsync_end = 176 + 2 + 3, |
186 | .htotal = 176 + 2 + 3 + 3, |
187 | .vdisplay = 220, |
188 | .vsync_start = 220 + 0, |
189 | .vsync_end = 220 + 0 + 2, |
190 | .vtotal = 220 + 0 + 2 + 1, |
191 | .flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC, |
192 | }, |
193 | .bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE, |
194 | }, |
195 | /* |
196 | * Sanyo ALR252RGT 240x320 portrait display found on the |
197 | * Versatile AB IB2 daughterboard for GSM prototyping. |
198 | */ |
199 | { |
200 | .name = "Sanyo ALR252RGT" , |
201 | .magic = SYS_CLCD_ID_SANYO_2_5, |
202 | .width_mm = 37, |
203 | .height_mm = 50, |
204 | .mode = { |
205 | .clock = 5400, |
206 | .hdisplay = 240, |
207 | .hsync_start = 240 + 10, |
208 | .hsync_end = 240 + 10 + 10, |
209 | .htotal = 240 + 10 + 10 + 20, |
210 | .vdisplay = 320, |
211 | .vsync_start = 320 + 2, |
212 | .vsync_end = 320 + 2 + 2, |
213 | .vtotal = 320 + 2 + 2 + 2, |
214 | .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC, |
215 | }, |
216 | .bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE, |
217 | .ib2 = true, |
218 | }, |
219 | }; |
220 | |
221 | static inline struct versatile_panel * |
222 | to_versatile_panel(struct drm_panel *panel) |
223 | { |
224 | return container_of(panel, struct versatile_panel, panel); |
225 | } |
226 | |
227 | static int versatile_panel_disable(struct drm_panel *panel) |
228 | { |
229 | struct versatile_panel *vpanel = to_versatile_panel(panel); |
230 | |
231 | /* If we're on an IB2 daughterboard, turn off display */ |
232 | if (vpanel->ib2_map) { |
233 | dev_dbg(vpanel->dev, "disable IB2 display\n" ); |
234 | regmap_update_bits(map: vpanel->ib2_map, |
235 | IB2_CTRL, |
236 | IB2_CTRL_LCD_MASK, |
237 | IB2_CTRL_LCD_SD); |
238 | } |
239 | |
240 | return 0; |
241 | } |
242 | |
243 | static int versatile_panel_enable(struct drm_panel *panel) |
244 | { |
245 | struct versatile_panel *vpanel = to_versatile_panel(panel); |
246 | |
247 | /* If we're on an IB2 daughterboard, turn on display */ |
248 | if (vpanel->ib2_map) { |
249 | dev_dbg(vpanel->dev, "enable IB2 display\n" ); |
250 | regmap_update_bits(map: vpanel->ib2_map, |
251 | IB2_CTRL, |
252 | IB2_CTRL_LCD_MASK, |
253 | IB2_CTRL_LCD_BL_ON); |
254 | } |
255 | |
256 | return 0; |
257 | } |
258 | |
259 | static int versatile_panel_get_modes(struct drm_panel *panel, |
260 | struct drm_connector *connector) |
261 | { |
262 | struct versatile_panel *vpanel = to_versatile_panel(panel); |
263 | struct drm_display_mode *mode; |
264 | |
265 | connector->display_info.width_mm = vpanel->panel_type->width_mm; |
266 | connector->display_info.height_mm = vpanel->panel_type->height_mm; |
267 | connector->display_info.bus_flags = vpanel->panel_type->bus_flags; |
268 | |
269 | mode = drm_mode_duplicate(dev: connector->dev, mode: &vpanel->panel_type->mode); |
270 | if (!mode) |
271 | return -ENOMEM; |
272 | drm_mode_set_name(mode); |
273 | mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED; |
274 | |
275 | mode->width_mm = vpanel->panel_type->width_mm; |
276 | mode->height_mm = vpanel->panel_type->height_mm; |
277 | drm_mode_probed_add(connector, mode); |
278 | |
279 | return 1; |
280 | } |
281 | |
282 | static const struct drm_panel_funcs versatile_panel_drm_funcs = { |
283 | .disable = versatile_panel_disable, |
284 | .enable = versatile_panel_enable, |
285 | .get_modes = versatile_panel_get_modes, |
286 | }; |
287 | |
288 | static int versatile_panel_probe(struct platform_device *pdev) |
289 | { |
290 | struct device *dev = &pdev->dev; |
291 | struct versatile_panel *vpanel; |
292 | struct device *parent; |
293 | struct regmap *map; |
294 | int ret; |
295 | u32 val; |
296 | int i; |
297 | |
298 | parent = dev->parent; |
299 | if (!parent) { |
300 | dev_err(dev, "no parent for versatile panel\n" ); |
301 | return -ENODEV; |
302 | } |
303 | map = syscon_node_to_regmap(np: parent->of_node); |
304 | if (IS_ERR(ptr: map)) { |
305 | dev_err(dev, "no regmap for versatile panel parent\n" ); |
306 | return PTR_ERR(ptr: map); |
307 | } |
308 | |
309 | vpanel = devm_kzalloc(dev, size: sizeof(*vpanel), GFP_KERNEL); |
310 | if (!vpanel) |
311 | return -ENOMEM; |
312 | |
313 | ret = regmap_read(map, SYS_CLCD, val: &val); |
314 | if (ret) { |
315 | dev_err(dev, "cannot access syscon regs\n" ); |
316 | return ret; |
317 | } |
318 | |
319 | val &= SYS_CLCD_CLCDID_MASK; |
320 | |
321 | for (i = 0; i < ARRAY_SIZE(versatile_panels); i++) { |
322 | const struct versatile_panel_type *pt; |
323 | |
324 | pt = &versatile_panels[i]; |
325 | if (pt->magic == val) { |
326 | vpanel->panel_type = pt; |
327 | break; |
328 | } |
329 | } |
330 | |
331 | /* No panel detected or VGA, let's leave this show */ |
332 | if (i == ARRAY_SIZE(versatile_panels)) { |
333 | dev_info(dev, "no panel detected\n" ); |
334 | return -ENODEV; |
335 | } |
336 | |
337 | dev_info(dev, "detected: %s\n" , vpanel->panel_type->name); |
338 | vpanel->dev = dev; |
339 | vpanel->map = map; |
340 | |
341 | /* Check if the panel is mounted on an IB2 daughterboard */ |
342 | if (vpanel->panel_type->ib2) { |
343 | vpanel->ib2_map = syscon_regmap_lookup_by_compatible( |
344 | s: "arm,versatile-ib2-syscon" ); |
345 | if (IS_ERR(ptr: vpanel->ib2_map)) |
346 | vpanel->ib2_map = NULL; |
347 | else |
348 | dev_info(dev, "panel mounted on IB2 daughterboard\n" ); |
349 | } |
350 | |
351 | drm_panel_init(panel: &vpanel->panel, dev, funcs: &versatile_panel_drm_funcs, |
352 | DRM_MODE_CONNECTOR_DPI); |
353 | |
354 | drm_panel_add(panel: &vpanel->panel); |
355 | |
356 | return 0; |
357 | } |
358 | |
359 | static const struct of_device_id versatile_panel_match[] = { |
360 | { .compatible = "arm,versatile-tft-panel" , }, |
361 | {}, |
362 | }; |
363 | MODULE_DEVICE_TABLE(of, versatile_panel_match); |
364 | |
365 | static struct platform_driver versatile_panel_driver = { |
366 | .probe = versatile_panel_probe, |
367 | .driver = { |
368 | .name = "versatile-tft-panel" , |
369 | .of_match_table = versatile_panel_match, |
370 | }, |
371 | }; |
372 | module_platform_driver(versatile_panel_driver); |
373 | |
374 | MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>" ); |
375 | MODULE_DESCRIPTION("ARM Versatile panel driver" ); |
376 | MODULE_LICENSE("GPL v2" ); |
377 | |