1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Exynos pinctrl driver common code.
4  * Copyright (C) 2016 Samsung Electronics
5  * Thomas Abraham <thomas.ab@samsung.com>
6  */
7 
8 #include <log.h>
9 #include <common.h>
10 #include <dm.h>
11 #include <errno.h>
12 #include <asm/global_data.h>
13 #include <asm/io.h>
14 #include "pinctrl-exynos.h"
15 
16 DECLARE_GLOBAL_DATA_PTR;
17 
18 /**
19  * exynos_pinctrl_setup_peri: setup pinctrl for a peripheral.
20  * conf: soc specific pin configuration data array
21  * num_conf: number of configurations in the conf array.
22  * base: base address of the pin controller.
23  */
exynos_pinctrl_setup_peri(struct exynos_pinctrl_config_data * conf,unsigned int num_conf,unsigned long base)24 void exynos_pinctrl_setup_peri(struct exynos_pinctrl_config_data *conf,
25 		unsigned int num_conf, unsigned long base)
26 {
27 	unsigned int idx, val;
28 
29 	for (idx = 0; idx < num_conf; idx++) {
30 		val = readl(base + conf[idx].offset);
31 		val &= ~(conf[idx].mask);
32 		val |= conf[idx].value;
33 		writel(val, base + conf[idx].offset);
34 	}
35 }
36 
37 /* given a pin-name, return the address of pin config registers */
pin_to_bank_base(struct udevice * dev,const char * pin_name,u32 * pin)38 static unsigned long pin_to_bank_base(struct udevice *dev, const char *pin_name,
39 						u32 *pin)
40 {
41 	struct exynos_pinctrl_priv *priv = dev_get_priv(dev);
42 	const struct samsung_pin_ctrl *pin_ctrl_array = priv->pin_ctrl;
43 	const struct samsung_pin_bank_data *bank_data;
44 	u32 nr_banks, pin_ctrl_idx = 0, idx = 0, bank_base;
45 	char bank[10];
46 
47 	/*
48 	 * The format of the pin name is <bank name>-<pin_number>.
49 	 * Example: gpa0-4 (gpa0 is the bank name and 4 is the pin number.
50 	 */
51 	while (pin_name[idx] != '-') {
52 		bank[idx] = pin_name[idx];
53 		idx++;
54 	}
55 	bank[idx] = '\0';
56 	*pin = pin_name[++idx] - '0';
57 
58 	/* lookup the pin bank data using the pin bank name */
59 	while (true) {
60 		const struct samsung_pin_ctrl *pin_ctrl = &pin_ctrl_array[pin_ctrl_idx];
61 
62 		nr_banks = pin_ctrl->nr_banks;
63 		if (!nr_banks)
64 			break;
65 
66 		bank_data = pin_ctrl->pin_banks;
67 		for (idx = 0; idx < nr_banks; idx++) {
68 			debug("pinctrl[%d] bank_data[%d] name is: %s\n",
69 					pin_ctrl_idx, idx, bank_data[idx].name);
70 			if (!strcmp(bank, bank_data[idx].name)) {
71 				bank_base = priv->base + bank_data[idx].offset;
72 				break;
73 			}
74 		}
75 		pin_ctrl_idx++;
76 	}
77 
78 	return bank_base;
79 }
80 
81 /**
82  * exynos_pinctrl_set_state: configure a pin state.
83  * dev: the pinctrl device to be configured.
84  * config: the state to be configured.
85  */
exynos_pinctrl_set_state(struct udevice * dev,struct udevice * config)86 int exynos_pinctrl_set_state(struct udevice *dev, struct udevice *config)
87 {
88 	const void *fdt = gd->fdt_blob;
89 	int node = dev_of_offset(config);
90 	unsigned int count, idx, pin_num;
91 	unsigned int pinfunc, pinpud, pindrv;
92 	unsigned long reg, value;
93 	const char *name;
94 
95 	/*
96 	 * refer to the following document for the pinctrl bindings
97 	 * linux/Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt
98 	 */
99 	count = fdt_stringlist_count(fdt, node, "samsung,pins");
100 	if (count <= 0)
101 		return -EINVAL;
102 
103 	pinfunc = fdtdec_get_int(fdt, node, "samsung,pin-function", -1);
104 	pinpud = fdtdec_get_int(fdt, node, "samsung,pin-pud", -1);
105 	pindrv = fdtdec_get_int(fdt, node, "samsung,pin-drv", -1);
106 
107 	for (idx = 0; idx < count; idx++) {
108 		name = fdt_stringlist_get(fdt, node, "samsung,pins", idx, NULL);
109 		if (!name)
110 			continue;
111 		reg = pin_to_bank_base(dev, name, &pin_num);
112 
113 		if (pinfunc != -1) {
114 			value = readl(reg + PIN_CON);
115 			value &= ~(0xf << (pin_num << 2));
116 			value |= (pinfunc << (pin_num << 2));
117 			writel(value, reg + PIN_CON);
118 		}
119 
120 		if (pinpud != -1) {
121 			value = readl(reg + PIN_PUD);
122 			value &= ~(0x3 << (pin_num << 1));
123 			value |= (pinpud << (pin_num << 1));
124 			writel(value, reg + PIN_PUD);
125 		}
126 
127 		if (pindrv != -1) {
128 			value = readl(reg + PIN_DRV);
129 			value &= ~(0x3 << (pin_num << 1));
130 			value |= (pindrv << (pin_num << 1));
131 			writel(value, reg + PIN_DRV);
132 		}
133 	}
134 
135 	return 0;
136 }
137 
exynos_pinctrl_probe(struct udevice * dev)138 int exynos_pinctrl_probe(struct udevice *dev)
139 {
140 	struct exynos_pinctrl_priv *priv;
141 	fdt_addr_t base;
142 
143 	priv = dev_get_priv(dev);
144 	if (!priv)
145 		return -EINVAL;
146 
147 	base = dev_read_addr(dev);
148 	if (base == FDT_ADDR_T_NONE)
149 		return -EINVAL;
150 
151 	priv->base = base;
152 	priv->pin_ctrl = (struct samsung_pin_ctrl *)dev_get_driver_data(dev) +
153 				dev_seq(dev);
154 
155 	return 0;
156 }
157