reset/pwr-mlxbf.c

   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");