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