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
26struct bcm283x_pinctrl_priv {
27	u32 *base_reg;
28};
29
30#define MAX_PINS_PER_BANK 16
31
32static 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
47static 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 */
63int 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
92static 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
101static const struct udevice_id bcm2835_pinctrl_id[] = {
102	{.compatible = "brcm,bcm2835-gpio"},
103	{.compatible = "brcm,bcm2711-gpio"},
104	{}
105};
106
107int 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
122int 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
143static struct pinctrl_ops bcm283x_pinctrl_ops = {
144	.set_state	= bcm283x_pinctrl_set_state,
145	.get_gpio_mux	= bcm283x_pinctrl_get_gpio_mux,
146};
147
148U_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 IS_ENABLED(CONFIG_OF_BOARD)
157	.flags		= DM_FLAG_PRE_RELOC,
158#endif
159};
160