xref: /openbmc/u-boot/drivers/gpio/gpio-uniphier.c (revision 8bf08b42)
1 /*
2  * Copyright (C) 2016 Masahiro Yamada <yamada.masahiro@socionext.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <dm/device.h>
9 #include <mapmem.h>
10 #include <linux/bitops.h>
11 #include <linux/io.h>
12 #include <asm/errno.h>
13 #include <asm/gpio.h>
14 
15 #define UNIPHIER_GPIO_PORTS_PER_BANK	8
16 
17 #define UNIPHIER_GPIO_REG_DATA		0	/* data */
18 #define UNIPHIER_GPIO_REG_DIR		4	/* direction (1:in, 0:out) */
19 
20 struct uniphier_gpio_priv {
21 	void __iomem *base;
22 	char bank_name[16];
23 };
24 
25 static void uniphier_gpio_offset_write(struct udevice *dev, unsigned offset,
26 				       unsigned reg, int value)
27 {
28 	struct uniphier_gpio_priv *priv = dev_get_priv(dev);
29 	u32 tmp;
30 
31 	tmp = readl(priv->base + reg);
32 	if (value)
33 		tmp |= BIT(offset);
34 	else
35 		tmp &= ~BIT(offset);
36 	writel(tmp, priv->base + reg);
37 }
38 
39 static int uniphier_gpio_offset_read(struct udevice *dev, unsigned offset,
40 				     unsigned reg)
41 {
42 	struct uniphier_gpio_priv *priv = dev_get_priv(dev);
43 
44 	return !!(readl(priv->base + reg) & BIT(offset));
45 }
46 
47 static int uniphier_gpio_direction_input(struct udevice *dev, unsigned offset)
48 {
49 	uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DIR, 1);
50 
51 	return 0;
52 }
53 
54 static int uniphier_gpio_direction_output(struct udevice *dev, unsigned offset,
55 					  int value)
56 {
57 	uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DATA, value);
58 	uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DIR, 0);
59 
60 	return 0;
61 }
62 
63 static int uniphier_gpio_get_value(struct udevice *dev, unsigned offset)
64 {
65 	return uniphier_gpio_offset_read(dev, offset, UNIPHIER_GPIO_REG_DATA);
66 }
67 
68 static int uniphier_gpio_set_value(struct udevice *dev, unsigned offset,
69 				   int value)
70 {
71 	uniphier_gpio_offset_write(dev, offset, UNIPHIER_GPIO_REG_DATA, value);
72 
73 	return 0;
74 }
75 
76 static int uniphier_gpio_get_function(struct udevice *dev, unsigned offset)
77 {
78 	return uniphier_gpio_offset_read(dev, offset, UNIPHIER_GPIO_REG_DIR) ?
79 						GPIOF_INPUT : GPIOF_OUTPUT;
80 }
81 
82 static const struct dm_gpio_ops uniphier_gpio_ops = {
83 	.direction_input	= uniphier_gpio_direction_input,
84 	.direction_output	= uniphier_gpio_direction_output,
85 	.get_value		= uniphier_gpio_get_value,
86 	.set_value		= uniphier_gpio_set_value,
87 	.get_function		= uniphier_gpio_get_function,
88 };
89 
90 static int uniphier_gpio_probe(struct udevice *dev)
91 {
92 	struct uniphier_gpio_priv *priv = dev_get_priv(dev);
93 	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
94 	DECLARE_GLOBAL_DATA_PTR;
95 	fdt_addr_t addr;
96 	fdt_size_t size;
97 	unsigned int tmp;
98 
99 	addr = fdtdec_get_addr_size(gd->fdt_blob, dev->of_offset, "reg",
100 				    &size);
101 	if (addr == FDT_ADDR_T_NONE)
102 		return -EINVAL;
103 
104 	priv->base = map_sysmem(addr, size);
105 	if (!priv->base)
106 		return -ENOMEM;
107 
108 	uc_priv->gpio_count = UNIPHIER_GPIO_PORTS_PER_BANK;
109 
110 	tmp = (addr & 0xfff);
111 
112 	/* Unfortunately, there is a register hole at offset 0x90-0x9f. */
113 	if (tmp > 0x90)
114 		tmp -= 0x10;
115 
116 	snprintf(priv->bank_name, sizeof(priv->bank_name) - 1,
117 		 "port%d-", (tmp - 8) / 8);
118 
119 	uc_priv->bank_name = priv->bank_name;
120 
121 	return 0;
122 }
123 
124 static int uniphier_gpio_remove(struct udevice *dev)
125 {
126 	struct uniphier_gpio_priv *priv = dev_get_priv(dev);
127 
128 	unmap_sysmem(priv->base);
129 
130 	return 0;
131 }
132 
133 /* .data = the number of GPIO banks */
134 static const struct udevice_id uniphier_gpio_match[] = {
135 	{ .compatible = "socionext,uniphier-gpio" },
136 	{ /* sentinel */ }
137 };
138 
139 U_BOOT_DRIVER(uniphier_gpio) = {
140 	.name	= "uniphier_gpio",
141 	.id	= UCLASS_GPIO,
142 	.of_match = uniphier_gpio_match,
143 	.probe	= uniphier_gpio_probe,
144 	.remove	= uniphier_gpio_remove,
145 	.priv_auto_alloc_size = sizeof(struct uniphier_gpio_priv),
146 	.ops	= &uniphier_gpio_ops,
147 };
148