xref: /linux/drivers/power/reset/pwr-mlxbf.c (revision d99ff463ecf651437e9e4abe68f331dfb6b5bd9d)
1 // SPDX-License-Identifier: GPL-2.0-only or BSD-3-Clause
2 
3 /*
4  *  Copyright (c) 2022 NVIDIA CORPORATION & AFFILIATES.
5  */
6 
7 #include <linux/acpi.h>
8 #include <linux/device.h>
9 #include <linux/devm-helpers.h>
10 #include <linux/interrupt.h>
11 #include <linux/kernel.h>
12 #include <linux/mod_devicetable.h>
13 #include <linux/module.h>
14 #include <linux/platform_device.h>
15 #include <linux/pm.h>
16 #include <linux/reboot.h>
17 #include <linux/types.h>
18 
19 struct pwr_mlxbf {
20 	struct work_struct send_work;
21 	const char *hid;
22 };
23 
24 static void pwr_mlxbf_send_work(struct work_struct *work)
25 {
26 	acpi_bus_generate_netlink_event("button/power.*", "Power Button", 0x80, 1);
27 }
28 
29 static irqreturn_t pwr_mlxbf_irq(int irq, void *ptr)
30 {
31 	const char *rst_pwr_hid = "MLNXBF24";
32 	const char *low_pwr_hid = "MLNXBF29";
33 	struct pwr_mlxbf *priv = ptr;
34 
35 	if (!strncmp(priv->hid, rst_pwr_hid, 8))
36 		emergency_restart();
37 
38 	if (!strncmp(priv->hid, low_pwr_hid, 8))
39 		schedule_work(&priv->send_work);
40 
41 	return IRQ_HANDLED;
42 }
43 
44 static int pwr_mlxbf_probe(struct platform_device *pdev)
45 {
46 	struct device *dev = &pdev->dev;
47 	struct acpi_device *adev;
48 	struct pwr_mlxbf *priv;
49 	const char *hid;
50 	int irq, err;
51 
52 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
53 	if (!priv)
54 		return -ENOMEM;
55 
56 	adev = ACPI_COMPANION(dev);
57 	if (!adev)
58 		return -ENXIO;
59 
60 	hid = acpi_device_hid(adev);
61 	priv->hid = hid;
62 
63 	irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
64 	if (irq < 0)
65 		return dev_err_probe(dev, irq, "Error getting %s irq.\n", priv->hid);
66 
67 	err = devm_work_autocancel(dev, &priv->send_work, pwr_mlxbf_send_work);
68 	if (err)
69 		return err;
70 
71 	err = devm_request_irq(dev, irq, pwr_mlxbf_irq, 0, hid, priv);
72 	if (err)
73 		dev_err(dev, "Failed request of %s irq\n", priv->hid);
74 
75 	return err;
76 }
77 
78 static const struct acpi_device_id __maybe_unused pwr_mlxbf_acpi_match[] = {
79 	{ "MLNXBF24", 0 },
80 	{ "MLNXBF29", 0 },
81 	{},
82 };
83 MODULE_DEVICE_TABLE(acpi, pwr_mlxbf_acpi_match);
84 
85 static struct platform_driver pwr_mlxbf_driver = {
86 	.driver = {
87 		.name = "pwr_mlxbf",
88 		.acpi_match_table = pwr_mlxbf_acpi_match,
89 	},
90 	.probe    = pwr_mlxbf_probe,
91 };
92 
93 module_platform_driver(pwr_mlxbf_driver);
94 
95 MODULE_DESCRIPTION("Mellanox BlueField power driver");
96 MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
97 MODULE_LICENSE("Dual BSD/GPL");
98