xref: /openbmc/u-boot/drivers/video/sunxi/sunxi_lcd.c (revision d66ff4ba)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Allwinner LCD driver
4  *
5  * (C) Copyright 2017 Vasily Khoruzhick <anarsoul@gmail.com>
6  */
7 
8 #include <common.h>
9 #include <display.h>
10 #include <video_bridge.h>
11 #include <backlight.h>
12 #include <dm.h>
13 #include <edid.h>
14 #include <asm/io.h>
15 #include <asm/arch/clock.h>
16 #include <asm/arch/lcdc.h>
17 #include <asm/arch/gpio.h>
18 #include <asm/gpio.h>
19 
20 struct sunxi_lcd_priv {
21 	struct display_timing timing;
22 	int panel_bpp;
23 };
24 
25 static void sunxi_lcdc_config_pinmux(void)
26 {
27 #ifdef CONFIG_MACH_SUN50I
28 	int pin;
29 
30 	for (pin = SUNXI_GPD(0); pin <= SUNXI_GPD(21); pin++) {
31 		sunxi_gpio_set_cfgpin(pin, SUNXI_GPD_LCD0);
32 		sunxi_gpio_set_drv(pin, 3);
33 	}
34 #endif
35 }
36 
37 static int sunxi_lcd_enable(struct udevice *dev, int bpp,
38 			    const struct display_timing *edid)
39 {
40 	struct sunxi_ccm_reg * const ccm =
41 	       (struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
42 	struct sunxi_lcdc_reg * const lcdc =
43 	       (struct sunxi_lcdc_reg *)SUNXI_LCD0_BASE;
44 	struct sunxi_lcd_priv *priv = dev_get_priv(dev);
45 	struct udevice *backlight;
46 	int clk_div, clk_double, ret;
47 
48 	/* Reset off */
49 	setbits_le32(&ccm->ahb_reset1_cfg, 1 << AHB_RESET_OFFSET_LCD0);
50 	/* Clock on */
51 	setbits_le32(&ccm->ahb_gate1, 1 << AHB_GATE_OFFSET_LCD0);
52 
53 	lcdc_init(lcdc);
54 	sunxi_lcdc_config_pinmux();
55 	lcdc_pll_set(ccm, 0, edid->pixelclock.typ / 1000,
56 		     &clk_div, &clk_double, false);
57 	lcdc_tcon0_mode_set(lcdc, edid, clk_div, false,
58 			    priv->panel_bpp, CONFIG_VIDEO_LCD_DCLK_PHASE);
59 	lcdc_enable(lcdc, priv->panel_bpp);
60 
61 	ret = uclass_get_device(UCLASS_PANEL_BACKLIGHT, 0, &backlight);
62 	if (!ret)
63 		backlight_enable(backlight);
64 
65 	return 0;
66 }
67 
68 static int sunxi_lcd_read_timing(struct udevice *dev,
69 				 struct display_timing *timing)
70 {
71 	struct sunxi_lcd_priv *priv = dev_get_priv(dev);
72 
73 	memcpy(timing, &priv->timing, sizeof(struct display_timing));
74 
75 	return 0;
76 }
77 
78 static int sunxi_lcd_probe(struct udevice *dev)
79 {
80 	struct udevice *cdev;
81 	struct sunxi_lcd_priv *priv = dev_get_priv(dev);
82 	int ret;
83 	int node, timing_node, val;
84 
85 #ifdef CONFIG_VIDEO_BRIDGE
86 	/* Try to get timings from bridge first */
87 	ret = uclass_get_device(UCLASS_VIDEO_BRIDGE, 0, &cdev);
88 	if (!ret) {
89 		u8 edid[EDID_SIZE];
90 		int channel_bpp;
91 
92 		ret = video_bridge_attach(cdev);
93 		if (ret) {
94 			debug("video bridge attach failed: %d\n", ret);
95 			return ret;
96 		}
97 		ret = video_bridge_read_edid(cdev, edid, EDID_SIZE);
98 		if (ret > 0) {
99 			ret = edid_get_timing(edid, ret,
100 					      &priv->timing, &channel_bpp);
101 			priv->panel_bpp = channel_bpp * 3;
102 			if (!ret)
103 				return ret;
104 		}
105 	}
106 #endif
107 
108 	/* Fallback to timings from DT if there's no bridge or
109 	 * if reading EDID failed
110 	 */
111 	ret = uclass_get_device(UCLASS_PANEL, 0, &cdev);
112 	if (ret) {
113 		debug("video panel not found: %d\n", ret);
114 		return ret;
115 	}
116 
117 	if (fdtdec_decode_display_timing(gd->fdt_blob, dev_of_offset(cdev),
118 					 0, &priv->timing)) {
119 		debug("%s: Failed to decode display timing\n", __func__);
120 		return -EINVAL;
121 	}
122 	timing_node = fdt_subnode_offset(gd->fdt_blob, dev_of_offset(cdev),
123 					 "display-timings");
124 	node = fdt_first_subnode(gd->fdt_blob, timing_node);
125 	val = fdtdec_get_int(gd->fdt_blob, node, "bits-per-pixel", -1);
126 	if (val != -1)
127 		priv->panel_bpp = val;
128 	else
129 		priv->panel_bpp = 18;
130 
131 	return 0;
132 }
133 
134 static const struct dm_display_ops sunxi_lcd_ops = {
135 	.read_timing = sunxi_lcd_read_timing,
136 	.enable = sunxi_lcd_enable,
137 };
138 
139 U_BOOT_DRIVER(sunxi_lcd) = {
140 	.name   = "sunxi_lcd",
141 	.id     = UCLASS_DISPLAY,
142 	.ops    = &sunxi_lcd_ops,
143 	.probe  = sunxi_lcd_probe,
144 	.priv_auto_alloc_size = sizeof(struct sunxi_lcd_priv),
145 };
146 
147 #ifdef CONFIG_MACH_SUN50I
148 U_BOOT_DEVICE(sunxi_lcd) = {
149 	.name = "sunxi_lcd"
150 };
151 #endif
152