xref: /linux/drivers/gpu/drm/sun4i/sun4i_tcon.c (revision cdd5b5a9761fd66d17586e4f4ba6588c70e640ea)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2015 Free Electrons
4  * Copyright (C) 2015 NextThing Co
5  *
6  * Maxime Ripard <maxime.ripard@free-electrons.com>
7  */
8 
9 #include <linux/component.h>
10 #include <linux/ioport.h>
11 #include <linux/media-bus-format.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_platform.h>
15 #include <linux/platform_device.h>
16 #include <linux/regmap.h>
17 #include <linux/reset.h>
18 
19 #include <drm/drm_atomic_helper.h>
20 #include <drm/drm_bridge.h>
21 #include <drm/drm_connector.h>
22 #include <drm/drm_crtc.h>
23 #include <drm/drm_encoder.h>
24 #include <drm/drm_modes.h>
25 #include <drm/drm_of.h>
26 #include <drm/drm_panel.h>
27 #include <drm/drm_print.h>
28 #include <drm/drm_probe_helper.h>
29 #include <drm/drm_vblank.h>
30 
31 #include <uapi/drm/drm_mode.h>
32 
33 #include "sun4i_crtc.h"
34 #include "sun4i_drv.h"
35 #include "sun4i_lvds.h"
36 #include "sun4i_rgb.h"
37 #include "sun4i_tcon.h"
38 #include "sun6i_mipi_dsi.h"
39 #include "sun4i_tcon_dclk.h"
40 #include "sun8i_tcon_top.h"
41 #include "sunxi_engine.h"
42 
sun4i_tcon_get_connector(const struct drm_encoder * encoder)43 static struct drm_connector *sun4i_tcon_get_connector(const struct drm_encoder *encoder)
44 {
45 	struct drm_connector *connector;
46 	struct drm_connector_list_iter iter;
47 
48 	drm_connector_list_iter_begin(encoder->dev, &iter);
49 	drm_for_each_connector_iter(connector, &iter)
50 		if (connector->encoder == encoder) {
51 			drm_connector_list_iter_end(&iter);
52 			return connector;
53 		}
54 	drm_connector_list_iter_end(&iter);
55 
56 	return NULL;
57 }
58 
sun4i_tcon_get_pixel_depth(const struct drm_encoder * encoder)59 static int sun4i_tcon_get_pixel_depth(const struct drm_encoder *encoder)
60 {
61 	struct drm_connector *connector;
62 	struct drm_display_info *info;
63 
64 	connector = sun4i_tcon_get_connector(encoder);
65 	if (!connector)
66 		return -EINVAL;
67 
68 	info = &connector->display_info;
69 	if (info->num_bus_formats != 1)
70 		return -EINVAL;
71 
72 	switch (info->bus_formats[0]) {
73 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
74 		return 18;
75 
76 	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
77 	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
78 		return 24;
79 	}
80 
81 	return -EINVAL;
82 }
83 
sun4i_tcon_channel_set_status(struct sun4i_tcon * tcon,int channel,bool enabled)84 static void sun4i_tcon_channel_set_status(struct sun4i_tcon *tcon, int channel,
85 					  bool enabled)
86 {
87 	struct clk *clk;
88 
89 	switch (channel) {
90 	case 0:
91 		WARN_ON(!tcon->quirks->has_channel_0);
92 		regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
93 				   SUN4I_TCON0_CTL_TCON_ENABLE,
94 				   enabled ? SUN4I_TCON0_CTL_TCON_ENABLE : 0);
95 		clk = tcon->dclk;
96 		break;
97 	case 1:
98 		WARN_ON(!tcon->quirks->has_channel_1);
99 		regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
100 				   SUN4I_TCON1_CTL_TCON_ENABLE,
101 				   enabled ? SUN4I_TCON1_CTL_TCON_ENABLE : 0);
102 		clk = tcon->sclk1;
103 		break;
104 	default:
105 		DRM_WARN("Unknown channel... doing nothing\n");
106 		return;
107 	}
108 
109 	if (enabled) {
110 		clk_prepare_enable(clk);
111 		clk_rate_exclusive_get(clk);
112 	} else {
113 		clk_rate_exclusive_put(clk);
114 		clk_disable_unprepare(clk);
115 	}
116 }
117 
sun4i_tcon_setup_lvds_phy(struct sun4i_tcon * tcon,const struct drm_encoder * encoder)118 static void sun4i_tcon_setup_lvds_phy(struct sun4i_tcon *tcon,
119 				      const struct drm_encoder *encoder)
120 {
121 	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
122 		     SUN4I_TCON0_LVDS_ANA0_CK_EN |
123 		     SUN4I_TCON0_LVDS_ANA0_REG_V |
124 		     SUN4I_TCON0_LVDS_ANA0_REG_C |
125 		     SUN4I_TCON0_LVDS_ANA0_EN_MB |
126 		     SUN4I_TCON0_LVDS_ANA0_PD |
127 		     SUN4I_TCON0_LVDS_ANA0_DCHS);
128 
129 	udelay(2); /* delay at least 1200 ns */
130 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA1_REG,
131 			   SUN4I_TCON0_LVDS_ANA1_INIT,
132 			   SUN4I_TCON0_LVDS_ANA1_INIT);
133 	udelay(1); /* delay at least 120 ns */
134 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA1_REG,
135 			   SUN4I_TCON0_LVDS_ANA1_UPDATE,
136 			   SUN4I_TCON0_LVDS_ANA1_UPDATE);
137 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
138 			   SUN4I_TCON0_LVDS_ANA0_EN_MB,
139 			   SUN4I_TCON0_LVDS_ANA0_EN_MB);
140 }
141 
sun6i_tcon_setup_lvds_phy(struct sun4i_tcon * tcon,const struct drm_encoder * encoder)142 static void sun6i_tcon_setup_lvds_phy(struct sun4i_tcon *tcon,
143 				      const struct drm_encoder *encoder)
144 {
145 	u8 val;
146 
147 	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
148 		     SUN6I_TCON0_LVDS_ANA0_C(2) |
149 		     SUN6I_TCON0_LVDS_ANA0_V(3) |
150 		     SUN6I_TCON0_LVDS_ANA0_PD(2) |
151 		     SUN6I_TCON0_LVDS_ANA0_EN_LDO);
152 	udelay(2);
153 
154 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
155 			   SUN6I_TCON0_LVDS_ANA0_EN_MB,
156 			   SUN6I_TCON0_LVDS_ANA0_EN_MB);
157 	udelay(2);
158 
159 	regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
160 			   SUN6I_TCON0_LVDS_ANA0_EN_DRVC,
161 			   SUN6I_TCON0_LVDS_ANA0_EN_DRVC);
162 
163 	if (sun4i_tcon_get_pixel_depth(encoder) == 18)
164 		val = 7;
165 	else
166 		val = 0xf;
167 
168 	regmap_write_bits(tcon->regs, SUN4I_TCON0_LVDS_ANA0_REG,
169 			  SUN6I_TCON0_LVDS_ANA0_EN_DRVD(0xf),
170 			  SUN6I_TCON0_LVDS_ANA0_EN_DRVD(val));
171 }
172 
sun4i_tcon_lvds_set_status(struct sun4i_tcon * tcon,const struct drm_encoder * encoder,bool enabled)173 static void sun4i_tcon_lvds_set_status(struct sun4i_tcon *tcon,
174 				       const struct drm_encoder *encoder,
175 				       bool enabled)
176 {
177 	if (enabled) {
178 		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_IF_REG,
179 				   SUN4I_TCON0_LVDS_IF_EN,
180 				   SUN4I_TCON0_LVDS_IF_EN);
181 		if (tcon->quirks->setup_lvds_phy)
182 			tcon->quirks->setup_lvds_phy(tcon, encoder);
183 	} else {
184 		regmap_update_bits(tcon->regs, SUN4I_TCON0_LVDS_IF_REG,
185 				   SUN4I_TCON0_LVDS_IF_EN, 0);
186 	}
187 }
188 
sun4i_tcon_set_status(struct sun4i_tcon * tcon,const struct drm_encoder * encoder,bool enabled)189 void sun4i_tcon_set_status(struct sun4i_tcon *tcon,
190 			   const struct drm_encoder *encoder,
191 			   bool enabled)
192 {
193 	bool is_lvds = false;
194 	int channel;
195 
196 	switch (encoder->encoder_type) {
197 	case DRM_MODE_ENCODER_LVDS:
198 		is_lvds = true;
199 		fallthrough;
200 	case DRM_MODE_ENCODER_DSI:
201 	case DRM_MODE_ENCODER_NONE:
202 		channel = 0;
203 		break;
204 	case DRM_MODE_ENCODER_TMDS:
205 	case DRM_MODE_ENCODER_TVDAC:
206 		channel = 1;
207 		break;
208 	default:
209 		DRM_DEBUG_DRIVER("Unknown encoder type, doing nothing...\n");
210 		return;
211 	}
212 
213 	if (is_lvds && !enabled)
214 		sun4i_tcon_lvds_set_status(tcon, encoder, false);
215 
216 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
217 			   SUN4I_TCON_GCTL_TCON_ENABLE,
218 			   enabled ? SUN4I_TCON_GCTL_TCON_ENABLE : 0);
219 
220 	if (is_lvds && enabled)
221 		sun4i_tcon_lvds_set_status(tcon, encoder, true);
222 
223 	sun4i_tcon_channel_set_status(tcon, channel, enabled);
224 }
225 
sun4i_tcon_enable_vblank(struct sun4i_tcon * tcon,bool enable)226 void sun4i_tcon_enable_vblank(struct sun4i_tcon *tcon, bool enable)
227 {
228 	u32 mask, val = 0;
229 
230 	DRM_DEBUG_DRIVER("%sabling VBLANK interrupt\n", enable ? "En" : "Dis");
231 
232 	mask = SUN4I_TCON_GINT0_VBLANK_ENABLE(0) |
233 		SUN4I_TCON_GINT0_VBLANK_ENABLE(1) |
234 		SUN4I_TCON_GINT0_TCON0_TRI_FINISH_ENABLE;
235 
236 	if (enable)
237 		val = mask;
238 
239 	regmap_update_bits(tcon->regs, SUN4I_TCON_GINT0_REG, mask, val);
240 }
241 EXPORT_SYMBOL(sun4i_tcon_enable_vblank);
242 
243 /*
244  * This function is a helper for TCON output muxing. The TCON output
245  * muxing control register in earlier SoCs (without the TCON TOP block)
246  * are located in TCON0. This helper returns a pointer to TCON0's
247  * sun4i_tcon structure, or NULL if not found.
248  */
sun4i_get_tcon0(struct drm_device * drm)249 static struct sun4i_tcon *sun4i_get_tcon0(struct drm_device *drm)
250 {
251 	struct sun4i_drv *drv = drm->dev_private;
252 	struct sun4i_tcon *tcon;
253 
254 	list_for_each_entry(tcon, &drv->tcon_list, list)
255 		if (tcon->id == 0)
256 			return tcon;
257 
258 	dev_warn(drm->dev,
259 		 "TCON0 not found, display output muxing may not work\n");
260 
261 	return NULL;
262 }
263 
sun4i_tcon_set_mux(struct sun4i_tcon * tcon,int channel,const struct drm_encoder * encoder)264 static void sun4i_tcon_set_mux(struct sun4i_tcon *tcon, int channel,
265 			       const struct drm_encoder *encoder)
266 {
267 	int ret = -ENOTSUPP;
268 
269 	if (tcon->quirks->set_mux)
270 		ret = tcon->quirks->set_mux(tcon, encoder);
271 
272 	DRM_DEBUG_DRIVER("Muxing encoder %s to CRTC %s: %d\n",
273 			 encoder->name, encoder->crtc->name, ret);
274 }
275 
sun4i_tcon_get_clk_delay(const struct drm_display_mode * mode,int channel)276 static int sun4i_tcon_get_clk_delay(const struct drm_display_mode *mode,
277 				    int channel)
278 {
279 	int delay = mode->vtotal - mode->vdisplay;
280 
281 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
282 		delay /= 2;
283 
284 	if (channel == 1)
285 		delay -= 2;
286 
287 	delay = min(delay, 30);
288 
289 	DRM_DEBUG_DRIVER("TCON %d clock delay %u\n", channel, delay);
290 
291 	return delay;
292 }
293 
sun4i_tcon0_mode_set_dithering(struct sun4i_tcon * tcon,const struct drm_connector * connector)294 static void sun4i_tcon0_mode_set_dithering(struct sun4i_tcon *tcon,
295 					   const struct drm_connector *connector)
296 {
297 	u32 bus_format = 0;
298 	u32 val = 0;
299 
300 	/* XXX Would this ever happen? */
301 	if (!connector)
302 		return;
303 
304 	/*
305 	 * FIXME: Undocumented bits
306 	 *
307 	 * The whole dithering process and these parameters are not
308 	 * explained in the vendor documents or BSP kernel code.
309 	 */
310 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PR_REG, 0x11111111);
311 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PG_REG, 0x11111111);
312 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_PB_REG, 0x11111111);
313 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LR_REG, 0x11111111);
314 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LG_REG, 0x11111111);
315 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_SEED_LB_REG, 0x11111111);
316 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL0_REG, 0x01010000);
317 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL1_REG, 0x15151111);
318 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL2_REG, 0x57575555);
319 	regmap_write(tcon->regs, SUN4I_TCON0_FRM_TBL3_REG, 0x7f7f7777);
320 
321 	/* Do dithering if panel only supports 6 bits per color */
322 	if (connector->display_info.bpc == 6)
323 		val |= SUN4I_TCON0_FRM_CTL_EN;
324 
325 	if (connector->display_info.num_bus_formats == 1)
326 		bus_format = connector->display_info.bus_formats[0];
327 
328 	/* Check the connection format */
329 	switch (bus_format) {
330 	case MEDIA_BUS_FMT_RGB565_1X16:
331 		/* R and B components are only 5 bits deep */
332 		val |= SUN4I_TCON0_FRM_CTL_MODE_R;
333 		val |= SUN4I_TCON0_FRM_CTL_MODE_B;
334 		fallthrough;
335 	case MEDIA_BUS_FMT_RGB666_1X18:
336 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
337 		/* Fall through: enable dithering */
338 		val |= SUN4I_TCON0_FRM_CTL_EN;
339 		break;
340 	}
341 
342 	/* Write dithering settings */
343 	regmap_write(tcon->regs, SUN4I_TCON_FRM_CTL_REG, val);
344 }
345 
sun4i_tcon0_mode_set_cpu(struct sun4i_tcon * tcon,const struct drm_encoder * encoder,const struct drm_display_mode * mode)346 static void sun4i_tcon0_mode_set_cpu(struct sun4i_tcon *tcon,
347 				     const struct drm_encoder *encoder,
348 				     const struct drm_display_mode *mode)
349 {
350 	/* TODO support normal CPU interface modes */
351 	struct sun6i_dsi *dsi = encoder_to_sun6i_dsi(encoder);
352 	struct mipi_dsi_device *device = dsi->device;
353 	u8 bpp = mipi_dsi_pixel_format_to_bpp(device->format);
354 	u8 lanes = device->lanes;
355 	u32 block_space, start_delay;
356 	u32 tcon_div;
357 
358 	/*
359 	 * dclk is required to run at 1/4 the DSI per-lane bit rate.
360 	 */
361 	tcon->dclk_min_div = SUN6I_DSI_TCON_DIV;
362 	tcon->dclk_max_div = SUN6I_DSI_TCON_DIV;
363 	clk_set_rate(tcon->dclk, mode->crtc_clock * 1000 * (bpp / lanes)
364 						  / SUN6I_DSI_TCON_DIV);
365 
366 	/* Set the resolution */
367 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG,
368 		     SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) |
369 		     SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay));
370 
371 	/* Set dithering if needed */
372 	sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder));
373 
374 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
375 			   SUN4I_TCON0_CTL_IF_MASK,
376 			   SUN4I_TCON0_CTL_IF_8080);
377 
378 	regmap_write(tcon->regs, SUN4I_TCON_ECC_FIFO_REG,
379 		     SUN4I_TCON_ECC_FIFO_EN);
380 
381 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_IF_REG,
382 		     SUN4I_TCON0_CPU_IF_MODE_DSI |
383 		     SUN4I_TCON0_CPU_IF_TRI_FIFO_FLUSH |
384 		     SUN4I_TCON0_CPU_IF_TRI_FIFO_EN |
385 		     SUN4I_TCON0_CPU_IF_TRI_EN);
386 
387 	/*
388 	 * This looks suspicious, but it works...
389 	 *
390 	 * The datasheet says that this should be set higher than 20 *
391 	 * pixel cycle, but it's not clear what a pixel cycle is.
392 	 */
393 	regmap_read(tcon->regs, SUN4I_TCON0_DCLK_REG, &tcon_div);
394 	tcon_div &= GENMASK(6, 0);
395 	block_space = mode->htotal * bpp / (tcon_div * lanes);
396 	block_space -= mode->hdisplay + 40;
397 
398 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI0_REG,
399 		     SUN4I_TCON0_CPU_TRI0_BLOCK_SPACE(block_space) |
400 		     SUN4I_TCON0_CPU_TRI0_BLOCK_SIZE(mode->hdisplay));
401 
402 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI1_REG,
403 		     SUN4I_TCON0_CPU_TRI1_BLOCK_NUM(mode->vdisplay));
404 
405 	start_delay = (mode->crtc_vtotal - mode->crtc_vdisplay - 10 - 1);
406 	start_delay = start_delay * mode->crtc_htotal * 149;
407 	start_delay = start_delay / (mode->crtc_clock / 1000) / 8;
408 	regmap_write(tcon->regs, SUN4I_TCON0_CPU_TRI2_REG,
409 		     SUN4I_TCON0_CPU_TRI2_TRANS_START_SET(10) |
410 		     SUN4I_TCON0_CPU_TRI2_START_DELAY(start_delay));
411 
412 	/*
413 	 * The Allwinner BSP has a comment that the period should be
414 	 * the display clock * 15, but uses an hardcoded 3000...
415 	 */
416 	regmap_write(tcon->regs, SUN4I_TCON_SAFE_PERIOD_REG,
417 		     SUN4I_TCON_SAFE_PERIOD_NUM(3000) |
418 		     SUN4I_TCON_SAFE_PERIOD_MODE(3));
419 
420 	/* Enable the output on the pins */
421 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG,
422 		     0xe0000000);
423 }
424 
sun4i_tcon0_mode_set_lvds(struct sun4i_tcon * tcon,const struct drm_encoder * encoder,const struct drm_display_mode * mode)425 static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon,
426 				      const struct drm_encoder *encoder,
427 				      const struct drm_display_mode *mode)
428 {
429 	unsigned int bp;
430 	u8 clk_delay;
431 	u32 reg, val = 0;
432 
433 	WARN_ON(!tcon->quirks->has_channel_0);
434 
435 	tcon->dclk_min_div = 7;
436 	tcon->dclk_max_div = 7;
437 	clk_set_rate(tcon->dclk, mode->crtc_clock * 1000);
438 
439 	/* Set the resolution */
440 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG,
441 		     SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) |
442 		     SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay));
443 
444 	/* Set dithering if needed */
445 	sun4i_tcon0_mode_set_dithering(tcon, sun4i_tcon_get_connector(encoder));
446 
447 	/* Adjust clock delay */
448 	clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
449 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
450 			   SUN4I_TCON0_CTL_CLK_DELAY_MASK,
451 			   SUN4I_TCON0_CTL_CLK_DELAY(clk_delay));
452 
453 	/*
454 	 * This is called a backporch in the register documentation,
455 	 * but it really is the back porch + hsync
456 	 */
457 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
458 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
459 			 mode->crtc_htotal, bp);
460 
461 	/* Set horizontal display timings */
462 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC1_REG,
463 		     SUN4I_TCON0_BASIC1_H_TOTAL(mode->htotal) |
464 		     SUN4I_TCON0_BASIC1_H_BACKPORCH(bp));
465 
466 	/*
467 	 * This is called a backporch in the register documentation,
468 	 * but it really is the back porch + hsync
469 	 */
470 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
471 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
472 			 mode->crtc_vtotal, bp);
473 
474 	/* Set vertical display timings */
475 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC2_REG,
476 		     SUN4I_TCON0_BASIC2_V_TOTAL(mode->crtc_vtotal * 2) |
477 		     SUN4I_TCON0_BASIC2_V_BACKPORCH(bp));
478 
479 	reg = SUN4I_TCON0_LVDS_IF_CLK_SEL_TCON0;
480 	if (sun4i_tcon_get_pixel_depth(encoder) == 24)
481 		reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_24BITS;
482 	else
483 		reg |= SUN4I_TCON0_LVDS_IF_BITWIDTH_18BITS;
484 
485 	regmap_write(tcon->regs, SUN4I_TCON0_LVDS_IF_REG, reg);
486 
487 	/* Setup the polarity of the various signals */
488 	if (!(mode->flags & DRM_MODE_FLAG_PHSYNC))
489 		val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
490 
491 	if (!(mode->flags & DRM_MODE_FLAG_PVSYNC))
492 		val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
493 
494 	regmap_write(tcon->regs, SUN4I_TCON0_IO_POL_REG, val);
495 
496 	/* Map output pins to channel 0 */
497 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
498 			   SUN4I_TCON_GCTL_IOMAP_MASK,
499 			   SUN4I_TCON_GCTL_IOMAP_TCON0);
500 
501 	/* Enable the output on the pins */
502 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0xe0000000);
503 }
504 
sun4i_tcon0_mode_set_rgb(struct sun4i_tcon * tcon,const struct drm_encoder * encoder,const struct drm_display_mode * mode)505 static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
506 				     const struct drm_encoder *encoder,
507 				     const struct drm_display_mode *mode)
508 {
509 	struct drm_connector *connector = sun4i_tcon_get_connector(encoder);
510 	const struct drm_display_info *info = &connector->display_info;
511 	unsigned int bp, hsync, vsync;
512 	u8 clk_delay;
513 	u32 val = 0;
514 
515 	WARN_ON(!tcon->quirks->has_channel_0);
516 
517 	tcon->dclk_min_div = tcon->quirks->dclk_min_div;
518 	tcon->dclk_max_div = 127;
519 	clk_set_rate(tcon->dclk, mode->crtc_clock * 1000);
520 
521 	/* Set the resolution */
522 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC0_REG,
523 		     SUN4I_TCON0_BASIC0_X(mode->crtc_hdisplay) |
524 		     SUN4I_TCON0_BASIC0_Y(mode->crtc_vdisplay));
525 
526 	/* Set dithering if needed */
527 	sun4i_tcon0_mode_set_dithering(tcon, connector);
528 
529 	/* Adjust clock delay */
530 	clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
531 	regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
532 			   SUN4I_TCON0_CTL_CLK_DELAY_MASK,
533 			   SUN4I_TCON0_CTL_CLK_DELAY(clk_delay));
534 
535 	/*
536 	 * This is called a backporch in the register documentation,
537 	 * but it really is the back porch + hsync
538 	 */
539 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
540 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
541 			 mode->crtc_htotal, bp);
542 
543 	/* Set horizontal display timings */
544 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC1_REG,
545 		     SUN4I_TCON0_BASIC1_H_TOTAL(mode->crtc_htotal) |
546 		     SUN4I_TCON0_BASIC1_H_BACKPORCH(bp));
547 
548 	/*
549 	 * This is called a backporch in the register documentation,
550 	 * but it really is the back porch + hsync
551 	 */
552 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
553 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
554 			 mode->crtc_vtotal, bp);
555 
556 	/* Set vertical display timings */
557 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC2_REG,
558 		     SUN4I_TCON0_BASIC2_V_TOTAL(mode->crtc_vtotal * 2) |
559 		     SUN4I_TCON0_BASIC2_V_BACKPORCH(bp));
560 
561 	/* Set Hsync and Vsync length */
562 	hsync = mode->crtc_hsync_end - mode->crtc_hsync_start;
563 	vsync = mode->crtc_vsync_end - mode->crtc_vsync_start;
564 	DRM_DEBUG_DRIVER("Setting HSYNC %d, VSYNC %d\n", hsync, vsync);
565 	regmap_write(tcon->regs, SUN4I_TCON0_BASIC3_REG,
566 		     SUN4I_TCON0_BASIC3_V_SYNC(vsync) |
567 		     SUN4I_TCON0_BASIC3_H_SYNC(hsync));
568 
569 	/* Setup the polarity of the various signals */
570 	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
571 		val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
572 
573 	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
574 		val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
575 
576 	if (info->bus_flags & DRM_BUS_FLAG_DE_LOW)
577 		val |= SUN4I_TCON0_IO_POL_DE_NEGATIVE;
578 
579 	if (info->bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE)
580 		val |= SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE;
581 
582 	regmap_update_bits(tcon->regs, SUN4I_TCON0_IO_POL_REG,
583 			   SUN4I_TCON0_IO_POL_HSYNC_POSITIVE |
584 			   SUN4I_TCON0_IO_POL_VSYNC_POSITIVE |
585 			   SUN4I_TCON0_IO_POL_DCLK_DRIVE_NEGEDGE |
586 			   SUN4I_TCON0_IO_POL_DE_NEGATIVE,
587 			   val);
588 
589 	/* Map output pins to channel 0 */
590 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
591 			   SUN4I_TCON_GCTL_IOMAP_MASK,
592 			   SUN4I_TCON_GCTL_IOMAP_TCON0);
593 
594 	/* Enable the output on the pins */
595 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, 0);
596 }
597 
sun4i_tcon1_mode_set(struct sun4i_tcon * tcon,const struct drm_display_mode * mode)598 static void sun4i_tcon1_mode_set(struct sun4i_tcon *tcon,
599 				 const struct drm_display_mode *mode)
600 {
601 	unsigned int bp, hsync, vsync, vtotal;
602 	u8 clk_delay;
603 	u32 val;
604 
605 	WARN_ON(!tcon->quirks->has_channel_1);
606 
607 	/* Configure the dot clock */
608 	clk_set_rate(tcon->sclk1, mode->crtc_clock * 1000);
609 
610 	/* Adjust clock delay */
611 	clk_delay = sun4i_tcon_get_clk_delay(mode, 1);
612 	regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
613 			   SUN4I_TCON1_CTL_CLK_DELAY_MASK,
614 			   SUN4I_TCON1_CTL_CLK_DELAY(clk_delay));
615 
616 	/* Set interlaced mode */
617 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)
618 		val = SUN4I_TCON1_CTL_INTERLACE_ENABLE;
619 	else
620 		val = 0;
621 	regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
622 			   SUN4I_TCON1_CTL_INTERLACE_ENABLE,
623 			   val);
624 
625 	/* Set the input resolution */
626 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC0_REG,
627 		     SUN4I_TCON1_BASIC0_X(mode->crtc_hdisplay) |
628 		     SUN4I_TCON1_BASIC0_Y(mode->crtc_vdisplay));
629 
630 	/* Set the upscaling resolution */
631 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC1_REG,
632 		     SUN4I_TCON1_BASIC1_X(mode->crtc_hdisplay) |
633 		     SUN4I_TCON1_BASIC1_Y(mode->crtc_vdisplay));
634 
635 	/* Set the output resolution */
636 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC2_REG,
637 		     SUN4I_TCON1_BASIC2_X(mode->crtc_hdisplay) |
638 		     SUN4I_TCON1_BASIC2_Y(mode->crtc_vdisplay));
639 
640 	/* Set horizontal display timings */
641 	bp = mode->crtc_htotal - mode->crtc_hsync_start;
642 	DRM_DEBUG_DRIVER("Setting horizontal total %d, backporch %d\n",
643 			 mode->htotal, bp);
644 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC3_REG,
645 		     SUN4I_TCON1_BASIC3_H_TOTAL(mode->crtc_htotal) |
646 		     SUN4I_TCON1_BASIC3_H_BACKPORCH(bp));
647 
648 	bp = mode->crtc_vtotal - mode->crtc_vsync_start;
649 	DRM_DEBUG_DRIVER("Setting vertical total %d, backporch %d\n",
650 			 mode->crtc_vtotal, bp);
651 
652 	/*
653 	 * The vertical resolution needs to be doubled in all
654 	 * cases. We could use crtc_vtotal and always multiply by two,
655 	 * but that leads to a rounding error in interlace when vtotal
656 	 * is odd.
657 	 *
658 	 * This happens with TV's PAL for example, where vtotal will
659 	 * be 625, crtc_vtotal 312, and thus crtc_vtotal * 2 will be
660 	 * 624, which apparently confuses the hardware.
661 	 *
662 	 * To work around this, we will always use vtotal, and
663 	 * multiply by two only if we're not in interlace.
664 	 */
665 	vtotal = mode->vtotal;
666 	if (!(mode->flags & DRM_MODE_FLAG_INTERLACE))
667 		vtotal = vtotal * 2;
668 
669 	/* Set vertical display timings */
670 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC4_REG,
671 		     SUN4I_TCON1_BASIC4_V_TOTAL(vtotal) |
672 		     SUN4I_TCON1_BASIC4_V_BACKPORCH(bp));
673 
674 	/* Set Hsync and Vsync length */
675 	hsync = mode->crtc_hsync_end - mode->crtc_hsync_start;
676 	vsync = mode->crtc_vsync_end - mode->crtc_vsync_start;
677 	DRM_DEBUG_DRIVER("Setting HSYNC %d, VSYNC %d\n", hsync, vsync);
678 	regmap_write(tcon->regs, SUN4I_TCON1_BASIC5_REG,
679 		     SUN4I_TCON1_BASIC5_V_SYNC(vsync) |
680 		     SUN4I_TCON1_BASIC5_H_SYNC(hsync));
681 
682 	/* Setup the polarity of multiple signals */
683 	if (tcon->quirks->polarity_in_ch0) {
684 		val = 0;
685 
686 		if (mode->flags & DRM_MODE_FLAG_PHSYNC)
687 			val |= SUN4I_TCON0_IO_POL_HSYNC_POSITIVE;
688 
689 		if (mode->flags & DRM_MODE_FLAG_PVSYNC)
690 			val |= SUN4I_TCON0_IO_POL_VSYNC_POSITIVE;
691 
692 		regmap_write(tcon->regs, SUN4I_TCON0_IO_POL_REG, val);
693 	} else {
694 		/* according to vendor driver, this bit must be always set */
695 		val = SUN4I_TCON1_IO_POL_UNKNOWN;
696 
697 		if (mode->flags & DRM_MODE_FLAG_PHSYNC)
698 			val |= SUN4I_TCON1_IO_POL_HSYNC_POSITIVE;
699 
700 		if (mode->flags & DRM_MODE_FLAG_PVSYNC)
701 			val |= SUN4I_TCON1_IO_POL_VSYNC_POSITIVE;
702 
703 		regmap_write(tcon->regs, SUN4I_TCON1_IO_POL_REG, val);
704 	}
705 
706 	/* Map output pins to channel 1 */
707 	regmap_update_bits(tcon->regs, SUN4I_TCON_GCTL_REG,
708 			   SUN4I_TCON_GCTL_IOMAP_MASK,
709 			   SUN4I_TCON_GCTL_IOMAP_TCON1);
710 }
711 
sun4i_tcon_mode_set(struct sun4i_tcon * tcon,const struct drm_encoder * encoder,const struct drm_display_mode * mode)712 void sun4i_tcon_mode_set(struct sun4i_tcon *tcon,
713 			 const struct drm_encoder *encoder,
714 			 const struct drm_display_mode *mode)
715 {
716 	switch (encoder->encoder_type) {
717 	case DRM_MODE_ENCODER_DSI:
718 		/* DSI is tied to special case of CPU interface */
719 		sun4i_tcon0_mode_set_cpu(tcon, encoder, mode);
720 		break;
721 	case DRM_MODE_ENCODER_LVDS:
722 		sun4i_tcon0_mode_set_lvds(tcon, encoder, mode);
723 		break;
724 	case DRM_MODE_ENCODER_NONE:
725 		sun4i_tcon0_mode_set_rgb(tcon, encoder, mode);
726 		sun4i_tcon_set_mux(tcon, 0, encoder);
727 		break;
728 	case DRM_MODE_ENCODER_TVDAC:
729 	case DRM_MODE_ENCODER_TMDS:
730 		sun4i_tcon1_mode_set(tcon, mode);
731 		sun4i_tcon_set_mux(tcon, 1, encoder);
732 		break;
733 	default:
734 		DRM_DEBUG_DRIVER("Unknown encoder type, doing nothing...\n");
735 	}
736 }
737 EXPORT_SYMBOL(sun4i_tcon_mode_set);
738 
sun4i_tcon_finish_page_flip(struct drm_device * dev,struct sun4i_crtc * scrtc)739 static void sun4i_tcon_finish_page_flip(struct drm_device *dev,
740 					struct sun4i_crtc *scrtc)
741 {
742 	unsigned long flags;
743 
744 	spin_lock_irqsave(&dev->event_lock, flags);
745 	if (scrtc->event) {
746 		drm_crtc_send_vblank_event(&scrtc->crtc, scrtc->event);
747 		drm_crtc_vblank_put(&scrtc->crtc);
748 		scrtc->event = NULL;
749 	}
750 	spin_unlock_irqrestore(&dev->event_lock, flags);
751 }
752 
sun4i_tcon_handler(int irq,void * private)753 static irqreturn_t sun4i_tcon_handler(int irq, void *private)
754 {
755 	struct sun4i_tcon *tcon = private;
756 	struct drm_device *drm = tcon->drm;
757 	struct sun4i_crtc *scrtc = tcon->crtc;
758 	struct sunxi_engine *engine = scrtc->engine;
759 	unsigned int status;
760 
761 	regmap_read(tcon->regs, SUN4I_TCON_GINT0_REG, &status);
762 
763 	if (!(status & (SUN4I_TCON_GINT0_VBLANK_INT(0) |
764 			SUN4I_TCON_GINT0_VBLANK_INT(1) |
765 			SUN4I_TCON_GINT0_TCON0_TRI_FINISH_INT)))
766 		return IRQ_NONE;
767 
768 	drm_crtc_handle_vblank(&scrtc->crtc);
769 	sun4i_tcon_finish_page_flip(drm, scrtc);
770 
771 	/* Acknowledge the interrupt */
772 	regmap_update_bits(tcon->regs, SUN4I_TCON_GINT0_REG,
773 			   SUN4I_TCON_GINT0_VBLANK_INT(0) |
774 			   SUN4I_TCON_GINT0_VBLANK_INT(1) |
775 			   SUN4I_TCON_GINT0_TCON0_TRI_FINISH_INT,
776 			   0);
777 
778 	if (engine->ops->vblank_quirk)
779 		engine->ops->vblank_quirk(engine);
780 
781 	return IRQ_HANDLED;
782 }
783 
sun4i_tcon_init_clocks(struct device * dev,struct sun4i_tcon * tcon)784 static int sun4i_tcon_init_clocks(struct device *dev,
785 				  struct sun4i_tcon *tcon)
786 {
787 	tcon->clk = devm_clk_get_enabled(dev, "ahb");
788 	if (IS_ERR(tcon->clk)) {
789 		dev_err(dev, "Couldn't get the TCON bus clock\n");
790 		return PTR_ERR(tcon->clk);
791 	}
792 
793 	if (tcon->quirks->has_channel_0) {
794 		tcon->sclk0 = devm_clk_get_enabled(dev, "tcon-ch0");
795 		if (IS_ERR(tcon->sclk0)) {
796 			dev_err(dev, "Couldn't get the TCON channel 0 clock\n");
797 			return PTR_ERR(tcon->sclk0);
798 		}
799 	}
800 
801 	if (tcon->quirks->has_channel_1) {
802 		tcon->sclk1 = devm_clk_get(dev, "tcon-ch1");
803 		if (IS_ERR(tcon->sclk1)) {
804 			dev_err(dev, "Couldn't get the TCON channel 1 clock\n");
805 			return PTR_ERR(tcon->sclk1);
806 		}
807 	}
808 
809 	return 0;
810 }
811 
sun4i_tcon_init_irq(struct device * dev,struct sun4i_tcon * tcon)812 static int sun4i_tcon_init_irq(struct device *dev,
813 			       struct sun4i_tcon *tcon)
814 {
815 	struct platform_device *pdev = to_platform_device(dev);
816 	int irq, ret;
817 
818 	irq = platform_get_irq(pdev, 0);
819 	if (irq < 0)
820 		return irq;
821 
822 	ret = devm_request_irq(dev, irq, sun4i_tcon_handler, 0,
823 			       dev_name(dev), tcon);
824 	if (ret) {
825 		dev_err(dev, "Couldn't request the IRQ\n");
826 		return ret;
827 	}
828 
829 	return 0;
830 }
831 
832 static const struct regmap_config sun4i_tcon_regmap_config = {
833 	.reg_bits	= 32,
834 	.val_bits	= 32,
835 	.reg_stride	= 4,
836 	.max_register	= 0x800,
837 };
838 
sun4i_tcon_init_regmap(struct device * dev,struct sun4i_tcon * tcon)839 static int sun4i_tcon_init_regmap(struct device *dev,
840 				  struct sun4i_tcon *tcon)
841 {
842 	struct platform_device *pdev = to_platform_device(dev);
843 	void __iomem *regs;
844 
845 	regs = devm_platform_ioremap_resource(pdev, 0);
846 	if (IS_ERR(regs))
847 		return PTR_ERR(regs);
848 
849 	tcon->regs = devm_regmap_init_mmio(dev, regs,
850 					   &sun4i_tcon_regmap_config);
851 	if (IS_ERR(tcon->regs)) {
852 		dev_err(dev, "Couldn't create the TCON regmap\n");
853 		return PTR_ERR(tcon->regs);
854 	}
855 
856 	/* Make sure the TCON is disabled and all IRQs are off */
857 	regmap_write(tcon->regs, SUN4I_TCON_GCTL_REG, 0);
858 	regmap_write(tcon->regs, SUN4I_TCON_GINT0_REG, 0);
859 	regmap_write(tcon->regs, SUN4I_TCON_GINT1_REG, 0);
860 
861 	/* Disable IO lines and set them to tristate */
862 	regmap_write(tcon->regs, SUN4I_TCON0_IO_TRI_REG, ~0);
863 	regmap_write(tcon->regs, SUN4I_TCON1_IO_TRI_REG, ~0);
864 
865 	return 0;
866 }
867 
868 /*
869  * On SoCs with the old display pipeline design (Display Engine 1.0),
870  * the TCON is always tied to just one backend. Hence we can traverse
871  * the of_graph upwards to find the backend our tcon is connected to,
872  * and take its ID as our own.
873  *
874  * We can either identify backends from their compatible strings, which
875  * means maintaining a large list of them. Or, since the backend is
876  * registered and binded before the TCON, we can just go through the
877  * list of registered backends and compare the device node.
878  *
879  * As the structures now store engines instead of backends, here this
880  * function in fact searches the corresponding engine, and the ID is
881  * requested via the get_id function of the engine.
882  */
883 static struct sunxi_engine *
sun4i_tcon_find_engine_traverse(struct sun4i_drv * drv,struct device_node * node,u32 port_id)884 sun4i_tcon_find_engine_traverse(struct sun4i_drv *drv,
885 				struct device_node *node,
886 				u32 port_id)
887 {
888 	struct device_node *port, *ep, *remote;
889 	struct sunxi_engine *engine = ERR_PTR(-EINVAL);
890 	u32 reg = 0;
891 
892 	port = of_graph_get_port_by_id(node, port_id);
893 	if (!port)
894 		return ERR_PTR(-EINVAL);
895 
896 	/*
897 	 * This only works if there is only one path from the TCON
898 	 * to any display engine. Otherwise the probe order of the
899 	 * TCONs and display engines is not guaranteed. They may
900 	 * either bind to the wrong one, or worse, bind to the same
901 	 * one if additional checks are not done.
902 	 *
903 	 * Bail out if there are multiple input connections.
904 	 */
905 	if (of_get_available_child_count(port) != 1)
906 		goto out_put_port;
907 
908 	/* Get the first connection without specifying an ID */
909 	ep = of_get_next_available_child(port, NULL);
910 	if (!ep)
911 		goto out_put_port;
912 
913 	remote = of_graph_get_remote_port_parent(ep);
914 	if (!remote)
915 		goto out_put_ep;
916 
917 	/* does this node match any registered engines? */
918 	list_for_each_entry(engine, &drv->engine_list, list)
919 		if (remote == engine->node)
920 			goto out_put_remote;
921 
922 	/*
923 	 * According to device tree binding input ports have even id
924 	 * number and output ports have odd id. Since component with
925 	 * more than one input and one output (TCON TOP) exits, correct
926 	 * remote input id has to be calculated by subtracting 1 from
927 	 * remote output id. If this for some reason can't be done, 0
928 	 * is used as input port id.
929 	 */
930 	of_node_put(port);
931 	port = of_graph_get_remote_port(ep);
932 	if (!of_property_read_u32(port, "reg", &reg) && reg > 0)
933 		reg -= 1;
934 
935 	/* keep looking through upstream ports */
936 	engine = sun4i_tcon_find_engine_traverse(drv, remote, reg);
937 
938 out_put_remote:
939 	of_node_put(remote);
940 out_put_ep:
941 	of_node_put(ep);
942 out_put_port:
943 	of_node_put(port);
944 
945 	return engine;
946 }
947 
948 /*
949  * The device tree binding says that the remote endpoint ID of any
950  * connection between components, up to and including the TCON, of
951  * the display pipeline should be equal to the actual ID of the local
952  * component. Thus we can look at any one of the input connections of
953  * the TCONs, and use that connection's remote endpoint ID as our own.
954  *
955  * Since the user of this function already finds the input port,
956  * the port is passed in directly without further checks.
957  */
sun4i_tcon_of_get_id_from_port(struct device_node * port)958 static int sun4i_tcon_of_get_id_from_port(struct device_node *port)
959 {
960 	struct device_node *ep;
961 	int ret = -EINVAL;
962 
963 	/* try finding an upstream endpoint */
964 	for_each_available_child_of_node(port, ep) {
965 		struct device_node *remote;
966 		u32 reg;
967 
968 		remote = of_graph_get_remote_endpoint(ep);
969 		if (!remote)
970 			continue;
971 
972 		ret = of_property_read_u32(remote, "reg", &reg);
973 		if (ret)
974 			continue;
975 
976 		ret = reg;
977 	}
978 
979 	return ret;
980 }
981 
982 /*
983  * Once we know the TCON's id, we can look through the list of
984  * engines to find a matching one. We assume all engines have
985  * been probed and added to the list.
986  */
sun4i_tcon_get_engine_by_id(struct sun4i_drv * drv,int id)987 static struct sunxi_engine *sun4i_tcon_get_engine_by_id(struct sun4i_drv *drv,
988 							int id)
989 {
990 	struct sunxi_engine *engine;
991 
992 	list_for_each_entry(engine, &drv->engine_list, list)
993 		if (engine->id == id)
994 			return engine;
995 
996 	return ERR_PTR(-EINVAL);
997 }
998 
sun4i_tcon_connected_to_tcon_top(struct device_node * node)999 static bool sun4i_tcon_connected_to_tcon_top(struct device_node *node)
1000 {
1001 	struct device_node *remote;
1002 	bool ret = false;
1003 
1004 	remote = of_graph_get_remote_node(node, 0, -1);
1005 	if (remote) {
1006 		ret = !!(IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP) &&
1007 			 of_match_node(sun8i_tcon_top_of_table, remote));
1008 		of_node_put(remote);
1009 	}
1010 
1011 	return ret;
1012 }
1013 
sun4i_tcon_get_index(struct sun4i_drv * drv)1014 static int sun4i_tcon_get_index(struct sun4i_drv *drv)
1015 {
1016 	struct list_head *pos;
1017 	int size = 0;
1018 
1019 	/*
1020 	 * Because TCON is added to the list at the end of the probe
1021 	 * (after this function is called), index of the current TCON
1022 	 * will be same as current TCON list size.
1023 	 */
1024 	list_for_each(pos, &drv->tcon_list)
1025 		++size;
1026 
1027 	return size;
1028 }
1029 
1030 /*
1031  * On SoCs with the old display pipeline design (Display Engine 1.0),
1032  * we assumed the TCON was always tied to just one backend. However
1033  * this proved not to be the case. On the A31, the TCON can select
1034  * either backend as its source. On the A20 (and likely on the A10),
1035  * the backend can choose which TCON to output to.
1036  *
1037  * The device tree binding says that the remote endpoint ID of any
1038  * connection between components, up to and including the TCON, of
1039  * the display pipeline should be equal to the actual ID of the local
1040  * component. Thus we should be able to look at any one of the input
1041  * connections of the TCONs, and use that connection's remote endpoint
1042  * ID as our own.
1043  *
1044  * However  the connections between the backend and TCON were assumed
1045  * to be always singular, and their endpoit IDs were all incorrectly
1046  * set to 0. This means for these old device trees, we cannot just look
1047  * up the remote endpoint ID of a TCON input endpoint. TCON1 would be
1048  * incorrectly identified as TCON0.
1049  *
1050  * This function first checks if the TCON node has 2 input endpoints.
1051  * If so, then the device tree is a corrected version, and it will use
1052  * sun4i_tcon_of_get_id() and sun4i_tcon_get_engine_by_id() from above
1053  * to fetch the ID and engine directly. If not, then it is likely an
1054  * old device trees, where the endpoint IDs were incorrect, but did not
1055  * have endpoint connections between the backend and TCON across
1056  * different display pipelines. It will fall back to the old method of
1057  * traversing the  of_graph to try and find a matching engine by device
1058  * node.
1059  *
1060  * In the case of single display pipeline device trees, either method
1061  * works.
1062  */
sun4i_tcon_find_engine(struct sun4i_drv * drv,struct device_node * node)1063 static struct sunxi_engine *sun4i_tcon_find_engine(struct sun4i_drv *drv,
1064 						   struct device_node *node)
1065 {
1066 	struct device_node *port;
1067 	struct sunxi_engine *engine;
1068 
1069 	port = of_graph_get_port_by_id(node, 0);
1070 	if (!port)
1071 		return ERR_PTR(-EINVAL);
1072 
1073 	/*
1074 	 * Is this a corrected device tree with cross pipeline
1075 	 * connections between the backend and TCON?
1076 	 */
1077 	if (of_get_child_count(port) > 1) {
1078 		int id;
1079 
1080 		/*
1081 		 * When pipeline has the same number of TCONs and engines which
1082 		 * are represented by frontends/backends (DE1) or mixers (DE2),
1083 		 * we match them by their respective IDs. However, if pipeline
1084 		 * contains TCON TOP, chances are that there are either more
1085 		 * TCONs than engines (R40) or TCONs with non-consecutive ids.
1086 		 * (H6). In that case it's easier just use TCON index in list
1087 		 * as an id. That means that on R40, any 2 TCONs can be enabled
1088 		 * in DT out of 4 (there are 2 mixers). Due to the design of
1089 		 * TCON TOP, remaining 2 TCONs can't be connected to anything
1090 		 * anyway.
1091 		 */
1092 		if (sun4i_tcon_connected_to_tcon_top(node))
1093 			id = sun4i_tcon_get_index(drv);
1094 		else
1095 			id = sun4i_tcon_of_get_id_from_port(port);
1096 
1097 		/* Get our engine by matching our ID */
1098 		engine = sun4i_tcon_get_engine_by_id(drv, id);
1099 
1100 		of_node_put(port);
1101 		return engine;
1102 	}
1103 
1104 	/* Fallback to old method by traversing input endpoints */
1105 	of_node_put(port);
1106 	return sun4i_tcon_find_engine_traverse(drv, node, 0);
1107 }
1108 
sun4i_tcon_bind(struct device * dev,struct device * master,void * data)1109 static int sun4i_tcon_bind(struct device *dev, struct device *master,
1110 			   void *data)
1111 {
1112 	struct drm_device *drm = data;
1113 	struct sun4i_drv *drv = drm->dev_private;
1114 	struct sunxi_engine *engine;
1115 	struct device_node *remote;
1116 	struct sun4i_tcon *tcon;
1117 	struct reset_control *edp_rstc;
1118 	bool has_lvds_rst, has_lvds_alt, can_lvds;
1119 	int ret;
1120 
1121 	engine = sun4i_tcon_find_engine(drv, dev->of_node);
1122 	if (IS_ERR(engine)) {
1123 		dev_err(dev, "Couldn't find matching engine\n");
1124 		return -EPROBE_DEFER;
1125 	}
1126 
1127 	tcon = devm_kzalloc(dev, sizeof(*tcon), GFP_KERNEL);
1128 	if (!tcon)
1129 		return -ENOMEM;
1130 	dev_set_drvdata(dev, tcon);
1131 	tcon->drm = drm;
1132 	tcon->dev = dev;
1133 	tcon->id = engine->id;
1134 	tcon->quirks = of_device_get_match_data(dev);
1135 
1136 	tcon->lcd_rst = devm_reset_control_get(dev, "lcd");
1137 	if (IS_ERR(tcon->lcd_rst)) {
1138 		dev_err(dev, "Couldn't get our reset line\n");
1139 		return PTR_ERR(tcon->lcd_rst);
1140 	}
1141 
1142 	if (tcon->quirks->needs_edp_reset) {
1143 		edp_rstc = devm_reset_control_get_shared(dev, "edp");
1144 		if (IS_ERR(edp_rstc)) {
1145 			dev_err(dev, "Couldn't get edp reset line\n");
1146 			return PTR_ERR(edp_rstc);
1147 		}
1148 
1149 		ret = reset_control_deassert(edp_rstc);
1150 		if (ret) {
1151 			dev_err(dev, "Couldn't deassert edp reset line\n");
1152 			return ret;
1153 		}
1154 	}
1155 
1156 	/* Make sure our TCON is reset */
1157 	ret = reset_control_reset(tcon->lcd_rst);
1158 	if (ret) {
1159 		dev_err(dev, "Couldn't deassert our reset line\n");
1160 		return ret;
1161 	}
1162 
1163 	if (tcon->quirks->supports_lvds) {
1164 		/*
1165 		 * This can only be made optional since we've had DT
1166 		 * nodes without the LVDS reset properties.
1167 		 *
1168 		 * If the property is missing, just disable LVDS, and
1169 		 * print a warning.
1170 		 */
1171 		tcon->lvds_rst = devm_reset_control_get_optional(dev, "lvds");
1172 		if (IS_ERR(tcon->lvds_rst)) {
1173 			dev_err(dev, "Couldn't get our reset line\n");
1174 			return PTR_ERR(tcon->lvds_rst);
1175 		} else if (tcon->lvds_rst) {
1176 			has_lvds_rst = true;
1177 			reset_control_reset(tcon->lvds_rst);
1178 		} else {
1179 			has_lvds_rst = false;
1180 		}
1181 
1182 		/*
1183 		 * This can only be made optional since we've had DT
1184 		 * nodes without the LVDS reset properties.
1185 		 *
1186 		 * If the property is missing, just disable LVDS, and
1187 		 * print a warning.
1188 		 */
1189 		if (tcon->quirks->has_lvds_alt) {
1190 			tcon->lvds_pll = devm_clk_get(dev, "lvds-alt");
1191 			if (IS_ERR(tcon->lvds_pll)) {
1192 				if (PTR_ERR(tcon->lvds_pll) == -ENOENT) {
1193 					has_lvds_alt = false;
1194 				} else {
1195 					dev_err(dev, "Couldn't get the LVDS PLL\n");
1196 					return PTR_ERR(tcon->lvds_pll);
1197 				}
1198 			} else {
1199 				has_lvds_alt = true;
1200 			}
1201 		}
1202 
1203 		if (!has_lvds_rst ||
1204 		    (tcon->quirks->has_lvds_alt && !has_lvds_alt)) {
1205 			dev_warn(dev, "Missing LVDS properties, Please upgrade your DT\n");
1206 			dev_warn(dev, "LVDS output disabled\n");
1207 			can_lvds = false;
1208 		} else {
1209 			can_lvds = true;
1210 		}
1211 	} else {
1212 		can_lvds = false;
1213 	}
1214 
1215 	ret = sun4i_tcon_init_clocks(dev, tcon);
1216 	if (ret) {
1217 		dev_err(dev, "Couldn't init our TCON clocks\n");
1218 		goto err_assert_reset;
1219 	}
1220 
1221 	ret = sun4i_tcon_init_regmap(dev, tcon);
1222 	if (ret) {
1223 		dev_err(dev, "Couldn't init our TCON regmap\n");
1224 		goto err_assert_reset;
1225 	}
1226 
1227 	if (tcon->quirks->has_channel_0) {
1228 		ret = sun4i_dclk_create(dev, tcon);
1229 		if (ret) {
1230 			dev_err(dev, "Couldn't create our TCON dot clock\n");
1231 			goto err_assert_reset;
1232 		}
1233 	}
1234 
1235 	ret = sun4i_tcon_init_irq(dev, tcon);
1236 	if (ret) {
1237 		dev_err(dev, "Couldn't init our TCON interrupts\n");
1238 		goto err_free_dclk;
1239 	}
1240 
1241 	tcon->crtc = sun4i_crtc_init(drm, engine, tcon);
1242 	if (IS_ERR(tcon->crtc)) {
1243 		dev_err(dev, "Couldn't create our CRTC\n");
1244 		ret = PTR_ERR(tcon->crtc);
1245 		goto err_free_dclk;
1246 	}
1247 
1248 	if (tcon->quirks->has_channel_0) {
1249 		/*
1250 		 * If we have an LVDS panel connected to the TCON, we should
1251 		 * just probe the LVDS connector. Otherwise, just probe RGB as
1252 		 * we used to.
1253 		 */
1254 		remote = of_graph_get_remote_node(dev->of_node, 1, 0);
1255 		if (of_device_is_compatible(remote, "panel-lvds"))
1256 			if (can_lvds)
1257 				ret = sun4i_lvds_init(drm, tcon);
1258 			else
1259 				ret = -EINVAL;
1260 		else
1261 			ret = sun4i_rgb_init(drm, tcon);
1262 		of_node_put(remote);
1263 
1264 		if (ret < 0)
1265 			goto err_free_dclk;
1266 	}
1267 
1268 	if (tcon->quirks->needs_de_be_mux) {
1269 		/*
1270 		 * We assume there is no dynamic muxing of backends
1271 		 * and TCONs, so we select the backend with same ID.
1272 		 *
1273 		 * While dynamic selection might be interesting, since
1274 		 * the CRTC is tied to the TCON, while the layers are
1275 		 * tied to the backends, this means, we will need to
1276 		 * switch between groups of layers. There might not be
1277 		 * a way to represent this constraint in DRM.
1278 		 */
1279 		regmap_update_bits(tcon->regs, SUN4I_TCON0_CTL_REG,
1280 				   SUN4I_TCON0_CTL_SRC_SEL_MASK,
1281 				   tcon->id);
1282 		regmap_update_bits(tcon->regs, SUN4I_TCON1_CTL_REG,
1283 				   SUN4I_TCON1_CTL_SRC_SEL_MASK,
1284 				   tcon->id);
1285 	}
1286 
1287 	list_add_tail(&tcon->list, &drv->tcon_list);
1288 
1289 	return 0;
1290 
1291 err_free_dclk:
1292 	if (tcon->quirks->has_channel_0)
1293 		sun4i_dclk_free(tcon);
1294 err_assert_reset:
1295 	reset_control_assert(tcon->lcd_rst);
1296 	return ret;
1297 }
1298 
sun4i_tcon_unbind(struct device * dev,struct device * master,void * data)1299 static void sun4i_tcon_unbind(struct device *dev, struct device *master,
1300 			      void *data)
1301 {
1302 	struct sun4i_tcon *tcon = dev_get_drvdata(dev);
1303 
1304 	list_del(&tcon->list);
1305 	if (tcon->quirks->has_channel_0)
1306 		sun4i_dclk_free(tcon);
1307 }
1308 
1309 static const struct component_ops sun4i_tcon_ops = {
1310 	.bind	= sun4i_tcon_bind,
1311 	.unbind	= sun4i_tcon_unbind,
1312 };
1313 
sun4i_tcon_probe(struct platform_device * pdev)1314 static int sun4i_tcon_probe(struct platform_device *pdev)
1315 {
1316 	struct device_node *node = pdev->dev.of_node;
1317 	const struct sun4i_tcon_quirks *quirks;
1318 	struct drm_bridge *bridge;
1319 	struct drm_panel *panel;
1320 	int ret;
1321 
1322 	quirks = of_device_get_match_data(&pdev->dev);
1323 
1324 	/* panels and bridges are present only on TCONs with channel 0 */
1325 	if (quirks->has_channel_0) {
1326 		ret = drm_of_find_panel_or_bridge(node, 1, 0, &panel, &bridge);
1327 		if (ret == -EPROBE_DEFER)
1328 			return ret;
1329 	}
1330 
1331 	return component_add(&pdev->dev, &sun4i_tcon_ops);
1332 }
1333 
sun4i_tcon_remove(struct platform_device * pdev)1334 static void sun4i_tcon_remove(struct platform_device *pdev)
1335 {
1336 	component_del(&pdev->dev, &sun4i_tcon_ops);
1337 }
1338 
1339 /* platform specific TCON muxing callbacks */
sun4i_a10_tcon_set_mux(struct sun4i_tcon * tcon,const struct drm_encoder * encoder)1340 static int sun4i_a10_tcon_set_mux(struct sun4i_tcon *tcon,
1341 				  const struct drm_encoder *encoder)
1342 {
1343 	struct sun4i_tcon *tcon0 = sun4i_get_tcon0(encoder->dev);
1344 	u32 shift;
1345 
1346 	if (!tcon0)
1347 		return -EINVAL;
1348 
1349 	switch (encoder->encoder_type) {
1350 	case DRM_MODE_ENCODER_TMDS:
1351 		/* HDMI */
1352 		shift = 8;
1353 		break;
1354 	default:
1355 		return -EINVAL;
1356 	}
1357 
1358 	regmap_update_bits(tcon0->regs, SUN4I_TCON_MUX_CTRL_REG,
1359 			   0x3 << shift, tcon->id << shift);
1360 
1361 	return 0;
1362 }
1363 
sun5i_a13_tcon_set_mux(struct sun4i_tcon * tcon,const struct drm_encoder * encoder)1364 static int sun5i_a13_tcon_set_mux(struct sun4i_tcon *tcon,
1365 				  const struct drm_encoder *encoder)
1366 {
1367 	u32 val;
1368 
1369 	if (encoder->encoder_type == DRM_MODE_ENCODER_TVDAC)
1370 		val = 1;
1371 	else
1372 		val = 0;
1373 
1374 	/*
1375 	 * FIXME: Undocumented bits
1376 	 */
1377 	return regmap_write(tcon->regs, SUN4I_TCON_MUX_CTRL_REG, val);
1378 }
1379 
sun6i_tcon_set_mux(struct sun4i_tcon * tcon,const struct drm_encoder * encoder)1380 static int sun6i_tcon_set_mux(struct sun4i_tcon *tcon,
1381 			      const struct drm_encoder *encoder)
1382 {
1383 	struct sun4i_tcon *tcon0 = sun4i_get_tcon0(encoder->dev);
1384 	u32 shift;
1385 
1386 	if (!tcon0)
1387 		return -EINVAL;
1388 
1389 	switch (encoder->encoder_type) {
1390 	case DRM_MODE_ENCODER_TMDS:
1391 		/* HDMI */
1392 		shift = 8;
1393 		break;
1394 	default:
1395 		/* TODO A31 has MIPI DSI but A31s does not */
1396 		return -EINVAL;
1397 	}
1398 
1399 	regmap_update_bits(tcon0->regs, SUN4I_TCON_MUX_CTRL_REG,
1400 			   0x3 << shift, tcon->id << shift);
1401 
1402 	return 0;
1403 }
1404 
sun8i_r40_tcon_tv_set_mux(struct sun4i_tcon * tcon,const struct drm_encoder * encoder)1405 static int sun8i_r40_tcon_tv_set_mux(struct sun4i_tcon *tcon,
1406 				     const struct drm_encoder *encoder)
1407 {
1408 	struct device_node *port, *remote;
1409 	struct platform_device *pdev;
1410 	int id, ret;
1411 
1412 	/* find TCON TOP platform device and TCON id */
1413 
1414 	port = of_graph_get_port_by_id(tcon->dev->of_node, 0);
1415 	if (!port)
1416 		return -EINVAL;
1417 
1418 	id = sun4i_tcon_of_get_id_from_port(port);
1419 	of_node_put(port);
1420 
1421 	remote = of_graph_get_remote_node(tcon->dev->of_node, 0, -1);
1422 	if (!remote)
1423 		return -EINVAL;
1424 
1425 	pdev = of_find_device_by_node(remote);
1426 	of_node_put(remote);
1427 	if (!pdev)
1428 		return -EINVAL;
1429 
1430 	if (IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP) &&
1431 	    encoder->encoder_type == DRM_MODE_ENCODER_TMDS) {
1432 		ret = sun8i_tcon_top_set_hdmi_src(&pdev->dev, id);
1433 		if (ret) {
1434 			put_device(&pdev->dev);
1435 			return ret;
1436 		}
1437 	}
1438 
1439 	if (IS_ENABLED(CONFIG_DRM_SUN8I_TCON_TOP)) {
1440 		ret = sun8i_tcon_top_de_config(&pdev->dev, tcon->id, id);
1441 		if (ret) {
1442 			put_device(&pdev->dev);
1443 			return ret;
1444 		}
1445 	}
1446 
1447 	return 0;
1448 }
1449 
1450 static const struct sun4i_tcon_quirks sun4i_a10_quirks = {
1451 	.has_channel_0		= true,
1452 	.has_channel_1		= true,
1453 	.dclk_min_div		= 4,
1454 	.set_mux		= sun4i_a10_tcon_set_mux,
1455 };
1456 
1457 static const struct sun4i_tcon_quirks sun5i_a13_quirks = {
1458 	.has_channel_0		= true,
1459 	.has_channel_1		= true,
1460 	.dclk_min_div		= 4,
1461 	.set_mux		= sun5i_a13_tcon_set_mux,
1462 };
1463 
1464 static const struct sun4i_tcon_quirks sun6i_a31_quirks = {
1465 	.has_channel_0		= true,
1466 	.has_channel_1		= true,
1467 	.has_lvds_alt		= true,
1468 	.needs_de_be_mux	= true,
1469 	.dclk_min_div		= 1,
1470 	.set_mux		= sun6i_tcon_set_mux,
1471 };
1472 
1473 static const struct sun4i_tcon_quirks sun6i_a31s_quirks = {
1474 	.has_channel_0		= true,
1475 	.has_channel_1		= true,
1476 	.needs_de_be_mux	= true,
1477 	.dclk_min_div		= 1,
1478 };
1479 
1480 static const struct sun4i_tcon_quirks sun7i_a20_tcon0_quirks = {
1481 	.supports_lvds		= true,
1482 	.has_channel_0		= true,
1483 	.has_channel_1		= true,
1484 	.dclk_min_div		= 4,
1485 	/* Same display pipeline structure as A10 */
1486 	.set_mux		= sun4i_a10_tcon_set_mux,
1487 	.setup_lvds_phy		= sun4i_tcon_setup_lvds_phy,
1488 };
1489 
1490 static const struct sun4i_tcon_quirks sun7i_a20_quirks = {
1491 	.has_channel_0		= true,
1492 	.has_channel_1		= true,
1493 	.dclk_min_div		= 4,
1494 	/* Same display pipeline structure as A10 */
1495 	.set_mux		= sun4i_a10_tcon_set_mux,
1496 };
1497 
1498 static const struct sun4i_tcon_quirks sun8i_a33_quirks = {
1499 	.has_channel_0		= true,
1500 	.has_lvds_alt		= true,
1501 	.dclk_min_div		= 1,
1502 	.setup_lvds_phy		= sun6i_tcon_setup_lvds_phy,
1503 	.supports_lvds		= true,
1504 };
1505 
1506 static const struct sun4i_tcon_quirks sun8i_a83t_lcd_quirks = {
1507 	.supports_lvds		= true,
1508 	.has_channel_0		= true,
1509 	.dclk_min_div		= 1,
1510 	.setup_lvds_phy		= sun6i_tcon_setup_lvds_phy,
1511 };
1512 
1513 static const struct sun4i_tcon_quirks sun8i_a83t_tv_quirks = {
1514 	.has_channel_1		= true,
1515 };
1516 
1517 static const struct sun4i_tcon_quirks sun8i_r40_tv_quirks = {
1518 	.has_channel_1		= true,
1519 	.polarity_in_ch0	= true,
1520 	.set_mux		= sun8i_r40_tcon_tv_set_mux,
1521 };
1522 
1523 static const struct sun4i_tcon_quirks sun8i_v3s_quirks = {
1524 	.has_channel_0		= true,
1525 	.dclk_min_div		= 1,
1526 };
1527 
1528 static const struct sun4i_tcon_quirks sun9i_a80_tcon_lcd_quirks = {
1529 	.has_channel_0		= true,
1530 	.needs_edp_reset	= true,
1531 	.dclk_min_div		= 1,
1532 };
1533 
1534 static const struct sun4i_tcon_quirks sun9i_a80_tcon_tv_quirks = {
1535 	.has_channel_1	= true,
1536 	.needs_edp_reset = true,
1537 };
1538 
1539 static const struct sun4i_tcon_quirks sun20i_d1_lcd_quirks = {
1540 	.has_channel_0		= true,
1541 	.dclk_min_div		= 1,
1542 	.set_mux		= sun8i_r40_tcon_tv_set_mux,
1543 };
1544 
1545 /* sun4i_drv uses this list to check if a device node is a TCON */
1546 const struct of_device_id sun4i_tcon_of_table[] = {
1547 	{ .compatible = "allwinner,sun4i-a10-tcon", .data = &sun4i_a10_quirks },
1548 	{ .compatible = "allwinner,sun5i-a13-tcon", .data = &sun5i_a13_quirks },
1549 	{ .compatible = "allwinner,sun6i-a31-tcon", .data = &sun6i_a31_quirks },
1550 	{ .compatible = "allwinner,sun6i-a31s-tcon", .data = &sun6i_a31s_quirks },
1551 	{ .compatible = "allwinner,sun7i-a20-tcon", .data = &sun7i_a20_quirks },
1552 	{ .compatible = "allwinner,sun7i-a20-tcon0", .data = &sun7i_a20_tcon0_quirks },
1553 	{ .compatible = "allwinner,sun7i-a20-tcon1", .data = &sun7i_a20_quirks },
1554 	{ .compatible = "allwinner,sun8i-a23-tcon", .data = &sun8i_a33_quirks },
1555 	{ .compatible = "allwinner,sun8i-a33-tcon", .data = &sun8i_a33_quirks },
1556 	{ .compatible = "allwinner,sun8i-a83t-tcon-lcd", .data = &sun8i_a83t_lcd_quirks },
1557 	{ .compatible = "allwinner,sun8i-a83t-tcon-tv", .data = &sun8i_a83t_tv_quirks },
1558 	{ .compatible = "allwinner,sun8i-r40-tcon-tv", .data = &sun8i_r40_tv_quirks },
1559 	{ .compatible = "allwinner,sun8i-v3s-tcon", .data = &sun8i_v3s_quirks },
1560 	{ .compatible = "allwinner,sun9i-a80-tcon-lcd", .data = &sun9i_a80_tcon_lcd_quirks },
1561 	{ .compatible = "allwinner,sun9i-a80-tcon-tv", .data = &sun9i_a80_tcon_tv_quirks },
1562 	{ .compatible = "allwinner,sun20i-d1-tcon-lcd", .data = &sun20i_d1_lcd_quirks },
1563 	{ .compatible = "allwinner,sun20i-d1-tcon-tv", .data = &sun8i_r40_tv_quirks },
1564 	{ }
1565 };
1566 MODULE_DEVICE_TABLE(of, sun4i_tcon_of_table);
1567 EXPORT_SYMBOL(sun4i_tcon_of_table);
1568 
1569 static struct platform_driver sun4i_tcon_platform_driver = {
1570 	.probe		= sun4i_tcon_probe,
1571 	.remove_new	= sun4i_tcon_remove,
1572 	.driver		= {
1573 		.name		= "sun4i-tcon",
1574 		.of_match_table	= sun4i_tcon_of_table,
1575 	},
1576 };
1577 module_platform_driver(sun4i_tcon_platform_driver);
1578 
1579 MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
1580 MODULE_DESCRIPTION("Allwinner A10 Timing Controller Driver");
1581 MODULE_LICENSE("GPL");
1582