xref: /openbmc/u-boot/drivers/video/sunxi/sunxi_lcd.c (revision cf0bcd7d)
1 /*
2  * Allwinner LCD driver
3  *
4  * (C) Copyright 2017 Vasily Khoruzhick <anarsoul@gmail.com>
5  *
6  * SPDX-License-Identifier:	GPL-2.0+
7  */
8 
9 #include <common.h>
10 #include <display.h>
11 #include <video_bridge.h>
12 #include <backlight.h>
13 #include <dm.h>
14 #include <edid.h>
15 #include <asm/io.h>
16 #include <asm/arch/clock.h>
17 #include <asm/arch/lcdc.h>
18 #include <asm/arch/gpio.h>
19 #include <asm/gpio.h>
20 
21 struct sunxi_lcd_priv {
22 	struct display_timing timing;
23 	int panel_bpp;
24 };
25 
26 static void sunxi_lcdc_config_pinmux(void)
27 {
28 #ifdef CONFIG_MACH_SUN50I
29 	int pin;
30 
31 	for (pin = SUNXI_GPD(0); pin <= SUNXI_GPD(21); pin++) {
32 		sunxi_gpio_set_cfgpin(pin, SUNXI_GPD_LCD0);
33 		sunxi_gpio_set_drv(pin, 3);
34 	}
35 #endif
36 }
37 
38 static int sunxi_lcd_enable(struct udevice *dev, int bpp,
39 			    const struct display_timing *edid)
40 {
41 	struct sunxi_ccm_reg * const ccm =
42 	       (struct sunxi_ccm_reg *)SUNXI_CCM_BASE;
43 	struct sunxi_lcdc_reg * const lcdc =
44 	       (struct sunxi_lcdc_reg *)SUNXI_LCD0_BASE;
45 	struct sunxi_lcd_priv *priv = dev_get_priv(dev);
46 	struct udevice *backlight;
47 	int clk_div, clk_double, ret;
48 
49 	/* Reset off */
50 	setbits_le32(&ccm->ahb_reset1_cfg, 1 << AHB_RESET_OFFSET_LCD0);
51 	/* Clock on */
52 	setbits_le32(&ccm->ahb_gate1, 1 << AHB_GATE_OFFSET_LCD0);
53 
54 	lcdc_init(lcdc);
55 	sunxi_lcdc_config_pinmux();
56 	lcdc_pll_set(ccm, 0, edid->pixelclock.typ / 1000,
57 		     &clk_div, &clk_double, false);
58 	lcdc_tcon0_mode_set(lcdc, edid, clk_div, false,
59 			    priv->panel_bpp, CONFIG_VIDEO_LCD_DCLK_PHASE);
60 	lcdc_enable(lcdc, priv->panel_bpp);
61 
62 	ret = uclass_get_device(UCLASS_PANEL_BACKLIGHT, 0, &backlight);
63 	if (!ret)
64 		backlight_enable(backlight);
65 
66 	return 0;
67 }
68 
69 static int sunxi_lcd_read_timing(struct udevice *dev,
70 				 struct display_timing *timing)
71 {
72 	struct sunxi_lcd_priv *priv = dev_get_priv(dev);
73 
74 	memcpy(timing, &priv->timing, sizeof(struct display_timing));
75 
76 	return 0;
77 }
78 
79 static int sunxi_lcd_probe(struct udevice *dev)
80 {
81 	struct udevice *cdev;
82 	struct sunxi_lcd_priv *priv = dev_get_priv(dev);
83 	int ret;
84 	int node, timing_node, val;
85 
86 #ifdef CONFIG_VIDEO_BRIDGE
87 	/* Try to get timings from bridge first */
88 	ret = uclass_get_device(UCLASS_VIDEO_BRIDGE, 0, &cdev);
89 	if (!ret) {
90 		u8 edid[EDID_SIZE];
91 		int channel_bpp;
92 
93 		ret = video_bridge_attach(cdev);
94 		if (ret) {
95 			debug("video bridge attach failed: %d\n", ret);
96 			return ret;
97 		}
98 		ret = video_bridge_read_edid(cdev, edid, EDID_SIZE);
99 		if (ret > 0) {
100 			ret = edid_get_timing(edid, ret,
101 					      &priv->timing, &channel_bpp);
102 			priv->panel_bpp = channel_bpp * 3;
103 			if (!ret)
104 				return ret;
105 		}
106 	}
107 #endif
108 
109 	/* Fallback to timings from DT if there's no bridge or
110 	 * if reading EDID failed
111 	 */
112 	ret = uclass_get_device(UCLASS_PANEL, 0, &cdev);
113 	if (ret) {
114 		debug("video panel not found: %d\n", ret);
115 		return ret;
116 	}
117 
118 	if (fdtdec_decode_display_timing(gd->fdt_blob, dev_of_offset(cdev),
119 					 0, &priv->timing)) {
120 		debug("%s: Failed to decode display timing\n", __func__);
121 		return -EINVAL;
122 	}
123 	timing_node = fdt_subnode_offset(gd->fdt_blob, dev_of_offset(cdev),
124 					 "display-timings");
125 	node = fdt_first_subnode(gd->fdt_blob, timing_node);
126 	val = fdtdec_get_int(gd->fdt_blob, node, "bits-per-pixel", -1);
127 	if (val != -1)
128 		priv->panel_bpp = val;
129 	else
130 		priv->panel_bpp = 18;
131 
132 	return 0;
133 }
134 
135 static const struct dm_display_ops sunxi_lcd_ops = {
136 	.read_timing = sunxi_lcd_read_timing,
137 	.enable = sunxi_lcd_enable,
138 };
139 
140 U_BOOT_DRIVER(sunxi_lcd) = {
141 	.name   = "sunxi_lcd",
142 	.id     = UCLASS_DISPLAY,
143 	.ops    = &sunxi_lcd_ops,
144 	.probe  = sunxi_lcd_probe,
145 	.priv_auto_alloc_size = sizeof(struct sunxi_lcd_priv),
146 };
147 
148 #ifdef CONFIG_MACH_SUN50I
149 U_BOOT_DEVICE(sunxi_lcd) = {
150 	.name = "sunxi_lcd"
151 };
152 #endif
153