summaryrefslogtreecommitdiff
path: root/drivers/gpio/hsdk-creg-gpio.c
blob: 66f8441840b54bb2d5f4b76cdf717bf80d17c60e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
/*
 * Synopsys HSDK SDP Generic PLL clock driver
 *
 * Copyright (C) 2017 Synopsys
 * Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <log.h>
#include <asm-generic/gpio.h>
#include <asm/io.h>
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <linux/bitops.h>
#include <linux/printk.h>

#define DRV_NAME	"gpio_creg"

struct hsdk_creg_gpio {
	u32	*regs;
	u8	shift;
	u8	activate;
	u8	deactivate;
	u8	bit_per_gpio;
};

static int hsdk_creg_gpio_set_value(struct udevice *dev, unsigned oft, int val)
{
	struct hsdk_creg_gpio *hcg = dev_get_priv(dev);
	u8 reg_shift = oft * hcg->bit_per_gpio + hcg->shift;
	u32 reg = readl(hcg->regs);

	reg &= ~(GENMASK(hcg->bit_per_gpio - 1, 0) << reg_shift);
	reg |=  ((val ? hcg->deactivate : hcg->activate) << reg_shift);

	writel(reg, hcg->regs);

	return 0;
}

static int hsdk_creg_gpio_direction_output(struct udevice *dev, unsigned oft,
					   int val)
{
	hsdk_creg_gpio_set_value(dev, oft, val);

	return 0;
}

static int hsdk_creg_gpio_direction_input(struct udevice *dev, unsigned oft)
{
	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);

	pr_err("%s can't be used as input!\n", uc_priv->bank_name);

	return -ENOTSUPP;
}

static int hsdk_creg_gpio_get_value(struct udevice *dev, unsigned int oft)
{
	struct hsdk_creg_gpio *hcg = dev_get_priv(dev);
	u32 val = readl(hcg->regs);

	val >>= oft * hcg->bit_per_gpio + hcg->shift;
	val &= GENMASK(hcg->bit_per_gpio - 1, 0);
	return (val == hcg->deactivate) ? 1 : 0;
}

static const struct dm_gpio_ops hsdk_creg_gpio_ops = {
	.direction_output	= hsdk_creg_gpio_direction_output,
	.direction_input	= hsdk_creg_gpio_direction_input,
	.set_value		= hsdk_creg_gpio_set_value,
	.get_value		= hsdk_creg_gpio_get_value,
};

static int hsdk_creg_gpio_probe(struct udevice *dev)
{
	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
	struct hsdk_creg_gpio *hcg = dev_get_priv(dev);
	u32 shift, bit_per_gpio, activate, deactivate, gpio_count;
	const u8 *defaults;

	hcg->regs = dev_read_addr_ptr(dev);
	gpio_count = dev_read_u32_default(dev, "gpio-count", 1);
	shift = dev_read_u32_default(dev, "gpio-first-shift", 0);
	bit_per_gpio = dev_read_u32_default(dev, "gpio-bit-per-line", 1);
	activate = dev_read_u32_default(dev, "gpio-activate-val", 1);
	deactivate = dev_read_u32_default(dev, "gpio-deactivate-val", 0);
	defaults = dev_read_u8_array_ptr(dev, "gpio-default-val", gpio_count);

	uc_priv->bank_name = dev_read_string(dev, "gpio-bank-name");
	if (!uc_priv->bank_name)
		uc_priv->bank_name = dev_read_name(dev);

	if (!bit_per_gpio) {
		pr_err("%s: 'gpio-bit-per-line' can't be 0\n",
		       uc_priv->bank_name);

		return -EINVAL;
	}

	if (!gpio_count) {
		pr_err("%s: 'gpio-count' can't be 0\n",
		       uc_priv->bank_name);

		return -EINVAL;
	}

	if ((gpio_count * bit_per_gpio + shift) > 32) {
		pr_err("%s: u32 io register overflow: try to use %u bits\n",
		       uc_priv->bank_name, gpio_count * bit_per_gpio + shift);

		return -EINVAL;
	}

	if (GENMASK(31, bit_per_gpio) & activate) {
		pr_err("%s: 'gpio-activate-val' can't be more than %lu\n",
		       uc_priv->bank_name, GENMASK(bit_per_gpio - 1, 0));

		return -EINVAL;
	}

	if (GENMASK(31, bit_per_gpio) & deactivate) {
		pr_err("%s: 'gpio-deactivate-val' can't be more than %lu\n",
		       uc_priv->bank_name, GENMASK(bit_per_gpio - 1, 0));

		return -EINVAL;
	}

	if (activate == deactivate) {
		pr_err("%s: 'gpio-deactivate-val' and 'gpio-activate-val' can't be equal\n",
		       uc_priv->bank_name);

		return -EINVAL;
	}

	hcg->shift = (u8)shift;
	hcg->bit_per_gpio = (u8)bit_per_gpio;
	hcg->activate = (u8)activate;
	hcg->deactivate = (u8)deactivate;
	uc_priv->gpio_count = gpio_count;

	/* Setup default GPIO value if we have "gpio-default-val" array */
	if (defaults)
		for (u8 i = 0; i < gpio_count; i++)
			hsdk_creg_gpio_set_value(dev, i, defaults[i]);

	pr_debug("%s GPIO [0x%p] controller with %d gpios probed\n",
		 uc_priv->bank_name, hcg->regs, uc_priv->gpio_count);

	return 0;
}

static const struct udevice_id hsdk_creg_gpio_ids[] = {
	{ .compatible = "snps,creg-gpio" },
	{ }
};

U_BOOT_DRIVER(gpio_hsdk_creg) = {
	.name	= DRV_NAME,
	.id	= UCLASS_GPIO,
	.ops	= &hsdk_creg_gpio_ops,
	.probe	= hsdk_creg_gpio_probe,
	.of_match = hsdk_creg_gpio_ids,
	.plat_auto	= sizeof(struct hsdk_creg_gpio),
};