1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/acpi.h>
4#include <linux/bitops.h>
5#include <linux/device.h>
6#include <linux/gpio/driver.h>
7#include <linux/io.h>
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/platform_device.h>
11#include <linux/pm.h>
12#include <linux/resource.h>
13#include <linux/types.h>
14
15/* Number of pins on BlueField */
16#define MLXBF_GPIO_NR 54
17
18/* Pad Electrical Controls. */
19#define MLXBF_GPIO_PAD_CONTROL_FIRST_WORD 0x0700
20#define MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD 0x0708
21#define MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD 0x0710
22#define MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD 0x0718
23
24#define MLXBF_GPIO_PIN_DIR_I 0x1040
25#define MLXBF_GPIO_PIN_DIR_O 0x1048
26#define MLXBF_GPIO_PIN_STATE 0x1000
27#define MLXBF_GPIO_SCRATCHPAD 0x20
28
29#ifdef CONFIG_PM
30struct mlxbf_gpio_context_save_regs {
31	u64 scratchpad;
32	u64 pad_control[MLXBF_GPIO_NR];
33	u64 pin_dir_i;
34	u64 pin_dir_o;
35};
36#endif
37
38/* Device state structure. */
39struct mlxbf_gpio_state {
40	struct gpio_chip gc;
41
42	/* Memory Address */
43	void __iomem *base;
44
45#ifdef CONFIG_PM
46	struct mlxbf_gpio_context_save_regs csave_regs;
47#endif
48};
49
50static int mlxbf_gpio_probe(struct platform_device *pdev)
51{
52	struct mlxbf_gpio_state *gs;
53	struct device *dev = &pdev->dev;
54	struct gpio_chip *gc;
55	int ret;
56
57	gs = devm_kzalloc(&pdev->dev, sizeof(*gs), GFP_KERNEL);
58	if (!gs)
59		return -ENOMEM;
60
61	gs->base = devm_platform_ioremap_resource(pdev, 0);
62	if (IS_ERR(gs->base))
63		return PTR_ERR(gs->base);
64
65	gc = &gs->gc;
66	ret = bgpio_init(gc, dev, 8,
67			 gs->base + MLXBF_GPIO_PIN_STATE,
68			 NULL,
69			 NULL,
70			 gs->base + MLXBF_GPIO_PIN_DIR_O,
71			 gs->base + MLXBF_GPIO_PIN_DIR_I,
72			 0);
73	if (ret)
74		return -ENODEV;
75
76	gc->owner = THIS_MODULE;
77	gc->ngpio = MLXBF_GPIO_NR;
78
79	ret = devm_gpiochip_add_data(dev, &gs->gc, gs);
80	if (ret) {
81		dev_err(&pdev->dev, "Failed adding memory mapped gpiochip\n");
82		return ret;
83	}
84
85	platform_set_drvdata(pdev, gs);
86	dev_info(&pdev->dev, "registered Mellanox BlueField GPIO");
87	return 0;
88}
89
90#ifdef CONFIG_PM
91static int mlxbf_gpio_suspend(struct platform_device *pdev, pm_message_t state)
92{
93	struct mlxbf_gpio_state *gs = platform_get_drvdata(pdev);
94
95	gs->csave_regs.scratchpad = readq(gs->base + MLXBF_GPIO_SCRATCHPAD);
96	gs->csave_regs.pad_control[0] =
97		readq(gs->base + MLXBF_GPIO_PAD_CONTROL_FIRST_WORD);
98	gs->csave_regs.pad_control[1] =
99		readq(gs->base + MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD);
100	gs->csave_regs.pad_control[2] =
101		readq(gs->base + MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD);
102	gs->csave_regs.pad_control[3] =
103		readq(gs->base + MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD);
104	gs->csave_regs.pin_dir_i = readq(gs->base + MLXBF_GPIO_PIN_DIR_I);
105	gs->csave_regs.pin_dir_o = readq(gs->base + MLXBF_GPIO_PIN_DIR_O);
106
107	return 0;
108}
109
110static int mlxbf_gpio_resume(struct platform_device *pdev)
111{
112	struct mlxbf_gpio_state *gs = platform_get_drvdata(pdev);
113
114	writeq(gs->csave_regs.scratchpad, gs->base + MLXBF_GPIO_SCRATCHPAD);
115	writeq(gs->csave_regs.pad_control[0],
116	       gs->base + MLXBF_GPIO_PAD_CONTROL_FIRST_WORD);
117	writeq(gs->csave_regs.pad_control[1],
118	       gs->base + MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD);
119	writeq(gs->csave_regs.pad_control[2],
120	       gs->base + MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD);
121	writeq(gs->csave_regs.pad_control[3],
122	       gs->base + MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD);
123	writeq(gs->csave_regs.pin_dir_i, gs->base + MLXBF_GPIO_PIN_DIR_I);
124	writeq(gs->csave_regs.pin_dir_o, gs->base + MLXBF_GPIO_PIN_DIR_O);
125
126	return 0;
127}
128#endif
129
130static const struct acpi_device_id __maybe_unused mlxbf_gpio_acpi_match[] = {
131	{ "MLNXBF02", 0 },
132	{}
133};
134MODULE_DEVICE_TABLE(acpi, mlxbf_gpio_acpi_match);
135
136static struct platform_driver mlxbf_gpio_driver = {
137	.driver = {
138		.name = "mlxbf_gpio",
139		.acpi_match_table = ACPI_PTR(mlxbf_gpio_acpi_match),
140	},
141	.probe    = mlxbf_gpio_probe,
142#ifdef CONFIG_PM
143	.suspend  = mlxbf_gpio_suspend,
144	.resume   = mlxbf_gpio_resume,
145#endif
146};
147
148module_platform_driver(mlxbf_gpio_driver);
149
150MODULE_DESCRIPTION("Mellanox BlueField GPIO Driver");
151MODULE_AUTHOR("Mellanox Technologies");
152MODULE_LICENSE("GPL");
153