xref: /openbmc/linux/drivers/power/reset/pwr-mlxbf.c (revision a5a3d94fc4edecb894bc79810aea511ff9261c09)
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 const char *rst_pwr_hid = "MLNXBF24";
20 const char *low_pwr_hid = "MLNXBF29";
21 
22 struct pwr_mlxbf {
23 	struct work_struct send_work;
24 	const char *hid;
25 };
26 
27 static void pwr_mlxbf_send_work(struct work_struct *work)
28 {
29 	acpi_bus_generate_netlink_event("button/power.*", "Power Button", 0x80, 1);
30 }
31 
32 static irqreturn_t pwr_mlxbf_irq(int irq, void *ptr)
33 {
34 	struct pwr_mlxbf *priv = ptr;
35 
36 	if (!strncmp(priv->hid, rst_pwr_hid, 8))
37 		emergency_restart();
38 
39 	if (!strncmp(priv->hid, low_pwr_hid, 8))
40 		schedule_work(&priv->send_work);
41 
42 	return IRQ_HANDLED;
43 }
44 
45 static int pwr_mlxbf_probe(struct platform_device *pdev)
46 {
47 	struct device *dev = &pdev->dev;
48 	struct acpi_device *adev;
49 	struct pwr_mlxbf *priv;
50 	const char *hid;
51 	int irq, err;
52 
53 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
54 	if (!priv)
55 		return -ENOMEM;
56 
57 	adev = ACPI_COMPANION(dev);
58 	if (!adev)
59 		return -ENXIO;
60 
61 	hid = acpi_device_hid(adev);
62 	priv->hid = hid;
63 
64 	irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0);
65 	if (irq < 0)
66 		return dev_err_probe(dev, irq, "Error getting %s irq.\n", priv->hid);
67 
68 	err = devm_work_autocancel(dev, &priv->send_work, pwr_mlxbf_send_work);
69 	if (err)
70 		return err;
71 
72 	err = devm_request_irq(dev, irq, pwr_mlxbf_irq, 0, hid, priv);
73 	if (err)
74 		dev_err(dev, "Failed request of %s irq\n", priv->hid);
75 
76 	return err;
77 }
78 
79 static const struct acpi_device_id __maybe_unused pwr_mlxbf_acpi_match[] = {
80 	{ "MLNXBF24", 0 },
81 	{ "MLNXBF29", 0 },
82 	{},
83 };
84 MODULE_DEVICE_TABLE(acpi, pwr_mlxbf_acpi_match);
85 
86 static struct platform_driver pwr_mlxbf_driver = {
87 	.driver = {
88 		.name = "pwr_mlxbf",
89 		.acpi_match_table = pwr_mlxbf_acpi_match,
90 	},
91 	.probe    = pwr_mlxbf_probe,
92 };
93 
94 module_platform_driver(pwr_mlxbf_driver);
95 
96 MODULE_DESCRIPTION("Mellanox BlueField power driver");
97 MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
98 MODULE_LICENSE("Dual BSD/GPL");
99