1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2020 MediaTek Inc. All Rights Reserved.
4 *
5 * Author: Weijie Gao <weijie.gao@mediatek.com>
6 *
7 * GPIO controller driver for MediaTek MT7620 SoC
8 */
9
10 #include <dm.h>
11 #include <errno.h>
12 #include <dm/device_compat.h>
13 #include <linux/bitops.h>
14 #include <linux/io.h>
15 #include <asm/gpio.h>
16
17 enum mt7620_regs {
18 GPIO_REG_DATA,
19 GPIO_REG_DIR,
20 GPIO_REG_SET,
21 GPIO_REG_CLR,
22
23 __GPIO_REG_MAX
24 };
25
26 struct mt7620_gpio_priv {
27 void __iomem *base;
28 u32 regs[__GPIO_REG_MAX];
29 u32 count;
30 };
31
mt7620_gpio_get_value(struct udevice * dev,unsigned int offset)32 static int mt7620_gpio_get_value(struct udevice *dev, unsigned int offset)
33 {
34 struct mt7620_gpio_priv *priv = dev_get_priv(dev);
35
36 return !!(readl(priv->base + priv->regs[GPIO_REG_DATA]) & BIT(offset));
37 }
38
mt7620_gpio_set_value(struct udevice * dev,unsigned int offset,int value)39 static int mt7620_gpio_set_value(struct udevice *dev, unsigned int offset,
40 int value)
41 {
42 struct mt7620_gpio_priv *priv = dev_get_priv(dev);
43 u32 reg;
44
45 reg = value ? priv->regs[GPIO_REG_SET] : priv->regs[GPIO_REG_CLR];
46
47 writel(BIT(offset), priv->base + reg);
48
49 return 0;
50 }
51
mt7620_gpio_direction_input(struct udevice * dev,unsigned int offset)52 static int mt7620_gpio_direction_input(struct udevice *dev, unsigned int offset)
53 {
54 struct mt7620_gpio_priv *priv = dev_get_priv(dev);
55
56 clrbits_32(priv->base + priv->regs[GPIO_REG_DIR], BIT(offset));
57
58 return 0;
59 }
60
mt7620_gpio_direction_output(struct udevice * dev,unsigned int offset,int value)61 static int mt7620_gpio_direction_output(struct udevice *dev,
62 unsigned int offset, int value)
63 {
64 struct mt7620_gpio_priv *priv = dev_get_priv(dev);
65
66 /* Set value first */
67 mt7620_gpio_set_value(dev, offset, value);
68
69 setbits_32(priv->base + priv->regs[GPIO_REG_DIR], BIT(offset));
70
71 return 0;
72 }
73
mt7620_gpio_get_function(struct udevice * dev,unsigned int offset)74 static int mt7620_gpio_get_function(struct udevice *dev, unsigned int offset)
75 {
76 struct mt7620_gpio_priv *priv = dev_get_priv(dev);
77
78 return (readl(priv->base + priv->regs[GPIO_REG_DIR]) & BIT(offset)) ?
79 GPIOF_OUTPUT : GPIOF_INPUT;
80 }
81
82 static const struct dm_gpio_ops mt7620_gpio_ops = {
83 .direction_input = mt7620_gpio_direction_input,
84 .direction_output = mt7620_gpio_direction_output,
85 .get_value = mt7620_gpio_get_value,
86 .set_value = mt7620_gpio_set_value,
87 .get_function = mt7620_gpio_get_function,
88 };
89
mt7620_gpio_probe(struct udevice * dev)90 static int mt7620_gpio_probe(struct udevice *dev)
91 {
92 struct mt7620_gpio_priv *priv = dev_get_priv(dev);
93 struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
94 const char *name;
95
96 name = dev_read_string(dev, "mediatek,bank-name");
97 if (!name)
98 name = dev->name;
99
100 uc_priv->gpio_count = priv->count;
101 uc_priv->bank_name = name;
102
103 return 0;
104 }
105
mt7620_gpio_of_to_plat(struct udevice * dev)106 static int mt7620_gpio_of_to_plat(struct udevice *dev)
107 {
108 struct mt7620_gpio_priv *priv = dev_get_priv(dev);
109 int ret;
110
111 priv->base = dev_remap_addr_index(dev, 0);
112 if (!priv->base) {
113 dev_err(dev, "mt7620_gpio: unable to map registers\n");
114 return -EINVAL;
115 }
116
117 ret = dev_read_u32(dev, "mediatek,gpio-num", &priv->count);
118 if (ret) {
119 dev_err(dev, "mt7620_gpio: failed to get GPIO count\n");
120 return -EINVAL;
121 }
122
123 ret = dev_read_u32_array(dev, "mediatek,register-map", priv->regs,
124 __GPIO_REG_MAX);
125 if (ret) {
126 dev_err(dev, "mt7620_gpio: unable to get register map\n");
127 return -EINVAL;
128 }
129
130 return 0;
131 }
132
133 static const struct udevice_id mt7620_gpio_ids[] = {
134 { .compatible = "mediatek,mt7620-gpio" },
135 { }
136 };
137
138 U_BOOT_DRIVER(mt7620_gpio) = {
139 .name = "mt7620_gpio",
140 .id = UCLASS_GPIO,
141 .ops = &mt7620_gpio_ops,
142 .of_match = mt7620_gpio_ids,
143 .probe = mt7620_gpio_probe,
144 .of_to_plat = mt7620_gpio_of_to_plat,
145 .priv_auto = sizeof(struct mt7620_gpio_priv),
146 };
147