xref: /openbmc/u-boot/drivers/gpio/gpio-rcar.c (revision 8ee59472)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2017 Marek Vasut <marek.vasut@gmail.com>
4  */
5 
6 #include <common.h>
7 #include <clk.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <asm/gpio.h>
11 #include <asm/io.h>
12 #include "../pinctrl/renesas/sh_pfc.h"
13 
14 #define GPIO_IOINTSEL	0x00	/* General IO/Interrupt Switching Register */
15 #define GPIO_INOUTSEL	0x04	/* General Input/Output Switching Register */
16 #define GPIO_OUTDT	0x08	/* General Output Register */
17 #define GPIO_INDT	0x0c	/* General Input Register */
18 #define GPIO_INTDT	0x10	/* Interrupt Display Register */
19 #define GPIO_INTCLR	0x14	/* Interrupt Clear Register */
20 #define GPIO_INTMSK	0x18	/* Interrupt Mask Register */
21 #define GPIO_MSKCLR	0x1c	/* Interrupt Mask Clear Register */
22 #define GPIO_POSNEG	0x20	/* Positive/Negative Logic Select Register */
23 #define GPIO_EDGLEVEL	0x24	/* Edge/level Select Register */
24 #define GPIO_FILONOFF	0x28	/* Chattering Prevention On/Off Register */
25 #define GPIO_BOTHEDGE	0x4c	/* One Edge/Both Edge Select Register */
26 
27 #define RCAR_MAX_GPIO_PER_BANK		32
28 
29 DECLARE_GLOBAL_DATA_PTR;
30 
31 struct rcar_gpio_priv {
32 	void __iomem		*regs;
33 	int			pfc_offset;
34 };
35 
36 static int rcar_gpio_get_value(struct udevice *dev, unsigned offset)
37 {
38 	struct rcar_gpio_priv *priv = dev_get_priv(dev);
39 	const u32 bit = BIT(offset);
40 
41 	/*
42 	 * Testing on r8a7790 shows that INDT does not show correct pin state
43 	 * when configured as output, so use OUTDT in case of output pins.
44 	 */
45 	if (readl(priv->regs + GPIO_INOUTSEL) & bit)
46 		return !!(readl(priv->regs + GPIO_OUTDT) & bit);
47 	else
48 		return !!(readl(priv->regs + GPIO_INDT) & bit);
49 }
50 
51 static int rcar_gpio_set_value(struct udevice *dev, unsigned offset,
52 			       int value)
53 {
54 	struct rcar_gpio_priv *priv = dev_get_priv(dev);
55 
56 	if (value)
57 		setbits_le32(priv->regs + GPIO_OUTDT, BIT(offset));
58 	else
59 		clrbits_le32(priv->regs + GPIO_OUTDT, BIT(offset));
60 
61 	return 0;
62 }
63 
64 static void rcar_gpio_set_direction(void __iomem *regs, unsigned offset,
65 				    bool output)
66 {
67 	/*
68 	 * follow steps in the GPIO documentation for
69 	 * "Setting General Output Mode" and
70 	 * "Setting General Input Mode"
71 	 */
72 
73 	/* Configure postive logic in POSNEG */
74 	clrbits_le32(regs + GPIO_POSNEG, BIT(offset));
75 
76 	/* Select "General Input/Output Mode" in IOINTSEL */
77 	clrbits_le32(regs + GPIO_IOINTSEL, BIT(offset));
78 
79 	/* Select Input Mode or Output Mode in INOUTSEL */
80 	if (output)
81 		setbits_le32(regs + GPIO_INOUTSEL, BIT(offset));
82 	else
83 		clrbits_le32(regs + GPIO_INOUTSEL, BIT(offset));
84 }
85 
86 static int rcar_gpio_direction_input(struct udevice *dev, unsigned offset)
87 {
88 	struct rcar_gpio_priv *priv = dev_get_priv(dev);
89 
90 	rcar_gpio_set_direction(priv->regs, offset, false);
91 
92 	return 0;
93 }
94 
95 static int rcar_gpio_direction_output(struct udevice *dev, unsigned offset,
96 				      int value)
97 {
98 	struct rcar_gpio_priv *priv = dev_get_priv(dev);
99 
100 	/* write GPIO value to output before selecting output mode of pin */
101 	rcar_gpio_set_value(dev, offset, value);
102 	rcar_gpio_set_direction(priv->regs, offset, true);
103 
104 	return 0;
105 }
106 
107 static int rcar_gpio_get_function(struct udevice *dev, unsigned offset)
108 {
109 	struct rcar_gpio_priv *priv = dev_get_priv(dev);
110 
111 	if (readl(priv->regs + GPIO_INOUTSEL) & BIT(offset))
112 		return GPIOF_OUTPUT;
113 	else
114 		return GPIOF_INPUT;
115 }
116 
117 static int rcar_gpio_request(struct udevice *dev, unsigned offset,
118 			     const char *label)
119 {
120 	struct rcar_gpio_priv *priv = dev_get_priv(dev);
121 	struct udevice *pctldev;
122 	int ret;
123 
124 	ret = uclass_get_device(UCLASS_PINCTRL, 0, &pctldev);
125 	if (ret)
126 		return ret;
127 
128 	return sh_pfc_config_mux_for_gpio(pctldev, priv->pfc_offset + offset);
129 }
130 
131 static const struct dm_gpio_ops rcar_gpio_ops = {
132 	.request		= rcar_gpio_request,
133 	.direction_input	= rcar_gpio_direction_input,
134 	.direction_output	= rcar_gpio_direction_output,
135 	.get_value		= rcar_gpio_get_value,
136 	.set_value		= rcar_gpio_set_value,
137 	.get_function		= rcar_gpio_get_function,
138 };
139 
140 static int rcar_gpio_probe(struct udevice *dev)
141 {
142 	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
143 	struct rcar_gpio_priv *priv = dev_get_priv(dev);
144 	struct fdtdec_phandle_args args;
145 	struct clk clk;
146 	int node = dev_of_offset(dev);
147 	int ret;
148 
149 	priv->regs = (void __iomem *)devfdt_get_addr(dev);
150 	uc_priv->bank_name = dev->name;
151 
152 	ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, node, "gpio-ranges",
153 					     NULL, 3, 0, &args);
154 	priv->pfc_offset = ret == 0 ? args.args[1] : -1;
155 	uc_priv->gpio_count = ret == 0 ? args.args[2] : RCAR_MAX_GPIO_PER_BANK;
156 
157 	ret = clk_get_by_index(dev, 0, &clk);
158 	if (ret < 0) {
159 		dev_err(dev, "Failed to get GPIO bank clock\n");
160 		return ret;
161 	}
162 
163 	ret = clk_enable(&clk);
164 	clk_free(&clk);
165 	if (ret) {
166 		dev_err(dev, "Failed to enable GPIO bank clock\n");
167 		return ret;
168 	}
169 
170 	return 0;
171 }
172 
173 static const struct udevice_id rcar_gpio_ids[] = {
174 	{ .compatible = "renesas,gpio-r8a7795" },
175 	{ .compatible = "renesas,gpio-r8a7796" },
176 	{ .compatible = "renesas,gpio-r8a77965" },
177 	{ .compatible = "renesas,gpio-r8a77970" },
178 	{ .compatible = "renesas,gpio-r8a77995" },
179 	{ .compatible = "renesas,rcar-gen2-gpio" },
180 	{ .compatible = "renesas,rcar-gen3-gpio" },
181 	{ /* sentinel */ }
182 };
183 
184 U_BOOT_DRIVER(rcar_gpio) = {
185 	.name	= "rcar-gpio",
186 	.id	= UCLASS_GPIO,
187 	.of_match = rcar_gpio_ids,
188 	.ops	= &rcar_gpio_ops,
189 	.priv_auto_alloc_size = sizeof(struct rcar_gpio_priv),
190 	.probe	= rcar_gpio_probe,
191 };
192