1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Copyright (c) 2015 Microchip Technology Inc
4 * Purna Chandra Mandal <purna.mandal@microchip.com>
5 */
6
7#include <common.h>
8#include <dm.h>
9#include <errno.h>
10#include <malloc.h>
11#include <asm/global_data.h>
12#include <asm/io.h>
13#include <asm/gpio.h>
14#include <linux/bitops.h>
15#include <linux/compat.h>
16#include <mach/pic32.h>
17
18DECLARE_GLOBAL_DATA_PTR;
19
20/* Peripheral Pin Control */
21struct pic32_reg_port {
22	struct pic32_reg_atomic ansel;
23	struct pic32_reg_atomic tris;
24	struct pic32_reg_atomic port;
25	struct pic32_reg_atomic lat;
26	struct pic32_reg_atomic open_drain;
27	struct pic32_reg_atomic cnpu;
28	struct pic32_reg_atomic cnpd;
29	struct pic32_reg_atomic cncon;
30};
31
32enum {
33	MICROCHIP_GPIO_DIR_OUT,
34	MICROCHIP_GPIO_DIR_IN,
35	MICROCHIP_GPIOS_PER_BANK = 16,
36};
37
38struct pic32_gpio_priv {
39	struct pic32_reg_port *regs;
40	char name[2];
41};
42
43static int pic32_gpio_get_value(struct udevice *dev, unsigned offset)
44{
45	struct pic32_gpio_priv *priv = dev_get_priv(dev);
46
47	return !!(readl(&priv->regs->port.raw) & BIT(offset));
48}
49
50static int pic32_gpio_set_value(struct udevice *dev, unsigned offset,
51				int value)
52{
53	struct pic32_gpio_priv *priv = dev_get_priv(dev);
54	int mask = BIT(offset);
55
56	if (value)
57		writel(mask, &priv->regs->port.set);
58	else
59		writel(mask, &priv->regs->port.clr);
60
61	return 0;
62}
63
64static int pic32_gpio_direction(struct udevice *dev, unsigned offset)
65{
66	struct pic32_gpio_priv *priv = dev_get_priv(dev);
67
68	/* pin in analog mode ? */
69	if (readl(&priv->regs->ansel.raw) & BIT(offset))
70		return -EPERM;
71
72	if (readl(&priv->regs->tris.raw) & BIT(offset))
73		return MICROCHIP_GPIO_DIR_IN;
74	else
75		return MICROCHIP_GPIO_DIR_OUT;
76}
77
78static int pic32_gpio_direction_input(struct udevice *dev, unsigned offset)
79{
80	struct pic32_gpio_priv *priv = dev_get_priv(dev);
81	int mask = BIT(offset);
82
83	writel(mask, &priv->regs->ansel.clr);
84	writel(mask, &priv->regs->tris.set);
85
86	return 0;
87}
88
89static int pic32_gpio_direction_output(struct udevice *dev,
90				       unsigned offset, int value)
91{
92	struct pic32_gpio_priv *priv = dev_get_priv(dev);
93	int mask = BIT(offset);
94
95	writel(mask, &priv->regs->ansel.clr);
96	writel(mask, &priv->regs->tris.clr);
97
98	pic32_gpio_set_value(dev, offset, value);
99	return 0;
100}
101
102static int pic32_gpio_get_function(struct udevice *dev, unsigned offset)
103{
104	int ret = GPIOF_UNUSED;
105
106	switch (pic32_gpio_direction(dev, offset)) {
107	case MICROCHIP_GPIO_DIR_OUT:
108		ret = GPIOF_OUTPUT;
109		break;
110	case MICROCHIP_GPIO_DIR_IN:
111		ret = GPIOF_INPUT;
112		break;
113	default:
114		ret = GPIOF_UNUSED;
115		break;
116	}
117	return ret;
118}
119
120static const struct dm_gpio_ops gpio_pic32_ops = {
121	.direction_input	= pic32_gpio_direction_input,
122	.direction_output	= pic32_gpio_direction_output,
123	.get_value		= pic32_gpio_get_value,
124	.set_value		= pic32_gpio_set_value,
125	.get_function		= pic32_gpio_get_function,
126};
127
128static int pic32_gpio_probe(struct udevice *dev)
129{
130	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
131	struct pic32_gpio_priv *priv = dev_get_priv(dev);
132	fdt_addr_t addr;
133	fdt_size_t size;
134	char *end;
135	int bank;
136
137	addr = fdtdec_get_addr_size(gd->fdt_blob, dev_of_offset(dev), "reg",
138				    &size);
139	if (addr == FDT_ADDR_T_NONE)
140		return -EINVAL;
141
142	priv->regs = ioremap(addr, size);
143
144	uc_priv->gpio_count = MICROCHIP_GPIOS_PER_BANK;
145	/* extract bank name */
146	end = strrchr(dev->name, '@');
147	bank = trailing_strtoln(dev->name, end);
148	priv->name[0] = 'A' + bank;
149	uc_priv->bank_name = priv->name;
150
151	return 0;
152}
153
154static const struct udevice_id pic32_gpio_ids[] = {
155	{ .compatible = "microchip,pic32mzda-gpio" },
156	{ }
157};
158
159U_BOOT_DRIVER(gpio_pic32) = {
160	.name		= "gpio_pic32",
161	.id		= UCLASS_GPIO,
162	.of_match	= pic32_gpio_ids,
163	.ops		= &gpio_pic32_ops,
164	.probe		= pic32_gpio_probe,
165	.priv_auto	= sizeof(struct pic32_gpio_priv),
166};
167