1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2018 Alexander Graf <agraf@suse.de>
4 *
5 * Based on drivers/pinctrl/mvebu/pinctrl-mvebu.c and
6 * drivers/gpio/bcm2835_gpio.c
7 *
8 * This driver gets instantiated by the GPIO driver, because both devices
9 * share the same device node.
10 * https://spdx.org/licenses
11 */
12
13 #include <common.h>
14 #include <config.h>
15 #include <errno.h>
16 #include <dm.h>
17 #include <log.h>
18 #include <dm/pinctrl.h>
19 #include <dm/root.h>
20 #include <dm/device-internal.h>
21 #include <dm/lists.h>
22 #include <asm/system.h>
23 #include <asm/io.h>
24 #include <asm/gpio.h>
25
26 struct bcm283x_pinctrl_priv {
27 u32 *base_reg;
28 };
29
30 #define MAX_PINS_PER_BANK 16
31
bcm2835_gpio_set_func_id(struct udevice * dev,unsigned int gpio,int func)32 static void bcm2835_gpio_set_func_id(struct udevice *dev, unsigned int gpio,
33 int func)
34 {
35 struct bcm283x_pinctrl_priv *priv = dev_get_priv(dev);
36 int reg_offset;
37 int field_offset;
38
39 reg_offset = BCM2835_GPIO_FSEL_BANK(gpio);
40 field_offset = BCM2835_GPIO_FSEL_SHIFT(gpio);
41
42 clrsetbits_le32(&priv->base_reg[reg_offset],
43 BCM2835_GPIO_FSEL_MASK << field_offset,
44 (func & BCM2835_GPIO_FSEL_MASK) << field_offset);
45 }
46
bcm2835_gpio_get_func_id(struct udevice * dev,unsigned int gpio)47 static int bcm2835_gpio_get_func_id(struct udevice *dev, unsigned int gpio)
48 {
49 struct bcm283x_pinctrl_priv *priv = dev_get_priv(dev);
50 u32 val;
51
52 val = readl(&priv->base_reg[BCM2835_GPIO_FSEL_BANK(gpio)]);
53
54 return (val >> BCM2835_GPIO_FSEL_SHIFT(gpio) & BCM2835_GPIO_FSEL_MASK);
55 }
56
57 /*
58 * bcm283x_pinctrl_set_state: configure pin functions.
59 * @dev: the pinctrl device to be configured.
60 * @config: the state to be configured.
61 * @return: 0 in success
62 */
bcm283x_pinctrl_set_state(struct udevice * dev,struct udevice * config)63 int bcm283x_pinctrl_set_state(struct udevice *dev, struct udevice *config)
64 {
65 u32 pin_arr[MAX_PINS_PER_BANK];
66 int function;
67 int i, len, pin_count = 0;
68
69 if (!dev_read_prop(config, "brcm,pins", &len) || !len ||
70 len & 0x3 || dev_read_u32_array(config, "brcm,pins", pin_arr,
71 len / sizeof(u32))) {
72 debug("Failed reading pins array for pinconfig %s (%d)\n",
73 config->name, len);
74 return -EINVAL;
75 }
76
77 pin_count = len / sizeof(u32);
78
79 function = dev_read_u32_default(config, "brcm,function", -1);
80 if (function < 0) {
81 debug("Failed reading function for pinconfig %s (%d)\n",
82 config->name, function);
83 return -EINVAL;
84 }
85
86 for (i = 0; i < pin_count; i++)
87 bcm2835_gpio_set_func_id(dev, pin_arr[i], function);
88
89 return 0;
90 }
91
bcm283x_pinctrl_get_gpio_mux(struct udevice * dev,int banknum,int index)92 static int bcm283x_pinctrl_get_gpio_mux(struct udevice *dev, int banknum,
93 int index)
94 {
95 if (banknum != 0)
96 return -EINVAL;
97
98 return bcm2835_gpio_get_func_id(dev, index);
99 }
100
101 static const struct udevice_id bcm2835_pinctrl_id[] = {
102 {.compatible = "brcm,bcm2835-gpio"},
103 {.compatible = "brcm,bcm2711-gpio"},
104 {}
105 };
106
bcm283x_pinctl_of_to_plat(struct udevice * dev)107 int bcm283x_pinctl_of_to_plat(struct udevice *dev)
108 {
109 struct bcm283x_pinctrl_priv *priv;
110
111 priv = dev_get_priv(dev);
112
113 priv->base_reg = dev_read_addr_ptr(dev);
114 if (!priv->base_reg) {
115 debug("%s: Failed to get base address\n", __func__);
116 return -EINVAL;
117 }
118
119 return 0;
120 }
121
bcm283x_pinctl_probe(struct udevice * dev)122 int bcm283x_pinctl_probe(struct udevice *dev)
123 {
124 int ret;
125 struct udevice *pdev;
126
127 /* Create GPIO device as well */
128 ret = device_bind(dev, lists_driver_lookup_name("gpio_bcm2835"),
129 "gpio_bcm2835", NULL, dev_ofnode(dev), &pdev);
130 if (ret) {
131 /*
132 * While we really want the pinctrl driver to work to make
133 * devices go where they should go, the GPIO controller is
134 * not quite as crucial as it's only rarely used, so don't
135 * fail here.
136 */
137 printf("Failed to bind GPIO driver\n");
138 }
139
140 return 0;
141 }
142
143 static struct pinctrl_ops bcm283x_pinctrl_ops = {
144 .set_state = bcm283x_pinctrl_set_state,
145 .get_gpio_mux = bcm283x_pinctrl_get_gpio_mux,
146 };
147
148 U_BOOT_DRIVER(pinctrl_bcm283x) = {
149 .name = "bcm283x_pinctrl",
150 .id = UCLASS_PINCTRL,
151 .of_match = of_match_ptr(bcm2835_pinctrl_id),
152 .of_to_plat = bcm283x_pinctl_of_to_plat,
153 .priv_auto = sizeof(struct bcm283x_pinctrl_priv),
154 .ops = &bcm283x_pinctrl_ops,
155 .probe = bcm283x_pinctl_probe,
156 #if CONFIG_IS_ENABLED(OF_BOARD)
157 .flags = DM_FLAG_PRE_RELOC,
158 #endif
159 };
160