xref: /openbmc/linux/drivers/gpio/gpio-mlxbf.c (revision 6ac2de95)
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
30 struct 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. */
39 struct 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 
mlxbf_gpio_probe(struct platform_device * pdev)50 static 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
mlxbf_gpio_suspend(struct platform_device * pdev,pm_message_t state)91 static 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 
mlxbf_gpio_resume(struct platform_device * pdev)110 static 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 
130 static const struct acpi_device_id __maybe_unused mlxbf_gpio_acpi_match[] = {
131 	{ "MLNXBF02", 0 },
132 	{}
133 };
134 MODULE_DEVICE_TABLE(acpi, mlxbf_gpio_acpi_match);
135 
136 static 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 
148 module_platform_driver(mlxbf_gpio_driver);
149 
150 MODULE_DESCRIPTION("Mellanox BlueField GPIO Driver");
151 MODULE_AUTHOR("Mellanox Technologies");
152 MODULE_LICENSE("GPL");
153