drivers/platform/x86/simatic-ipc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Siemens SIMATIC IPC platform driver
   4  *
   5  * Copyright (c) Siemens AG, 2018-2021
   6  *
   7  * Authors:
   8  *  Henning Schild <[email protected]>
   9  *  Jan Kiszka <[email protected]>
  10  *  Gerd Haeussler <[email protected]>
  11  */
  12
  13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15 #include <linux/dmi.h>
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/pci.h>
  19 #include <linux/platform_data/x86/simatic-ipc.h>
  20 #include <linux/platform_device.h>
  21
  22 static struct platform_device *ipc_led_platform_device;
  23 static struct platform_device *ipc_wdt_platform_device;
  24
  25 static const struct dmi_system_id simatic_ipc_whitelist[] = {
  26         {
  27                 .matches = {
  28                         DMI_MATCH(DMI_SYS_VENDOR, "SIEMENS AG"),
  29                 },
  30         },
  31         {}
  32 };
  33
  34 static struct simatic_ipc_platform platform_data;
  35
  36 static struct {
  37         u32 station_id;
  38         u8 led_mode;
  39         u8 wdt_mode;
  40 } device_modes[] = {
  41         {SIMATIC_IPC_IPC127E, SIMATIC_IPC_DEVICE_127E, SIMATIC_IPC_DEVICE_NONE},
  42         {SIMATIC_IPC_IPC227D, SIMATIC_IPC_DEVICE_227D, SIMATIC_IPC_DEVICE_NONE},
  43         {SIMATIC_IPC_IPC227E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_227E},
  44         {SIMATIC_IPC_IPC227G, SIMATIC_IPC_DEVICE_227G, SIMATIC_IPC_DEVICE_227G},
  45         {SIMATIC_IPC_IPC277E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_227E},
  46         {SIMATIC_IPC_IPC427D, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_NONE},
  47         {SIMATIC_IPC_IPC427E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_427E},
  48         {SIMATIC_IPC_IPC477E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_427E},
  49         {SIMATIC_IPC_IPC427G, SIMATIC_IPC_DEVICE_227G, SIMATIC_IPC_DEVICE_227G},
  50 };
  51
  52 static int register_platform_devices(u32 station_id)
  53 {
  54         u8 ledmode = SIMATIC_IPC_DEVICE_NONE;
  55         u8 wdtmode = SIMATIC_IPC_DEVICE_NONE;
  56         char *pdevname = KBUILD_MODNAME "_leds";
  57         int i;
  58
  59         platform_data.devmode = SIMATIC_IPC_DEVICE_NONE;
  60
  61         for (i = 0; i < ARRAY_SIZE(device_modes); i++) {
  62                 if (device_modes[i].station_id == station_id) {
  63                         ledmode = device_modes[i].led_mode;
  64                         wdtmode = device_modes[i].wdt_mode;
  65                         break;
  66                 }
  67         }
  68
  69         if (ledmode != SIMATIC_IPC_DEVICE_NONE) {
  70                 if (ledmode == SIMATIC_IPC_DEVICE_127E ||
  71                     ledmode == SIMATIC_IPC_DEVICE_227G)
  72                         pdevname = KBUILD_MODNAME "_leds_gpio";
  73                 platform_data.devmode = ledmode;
  74                 ipc_led_platform_device =
  75                         platform_device_register_data(NULL,
  76                                 pdevname, PLATFORM_DEVID_NONE,
  77                                 &platform_data,
  78                                 sizeof(struct simatic_ipc_platform));
  79                 if (IS_ERR(ipc_led_platform_device))
  80                         return PTR_ERR(ipc_led_platform_device);
  81
  82                 pr_debug("device=%s created\n",
  83                          ipc_led_platform_device->name);
  84         }
  85
  86         if (wdtmode == SIMATIC_IPC_DEVICE_227G) {
  87                 request_module("w83627hf_wdt");
  88                 return 0;
  89         }
  90
  91         if (wdtmode != SIMATIC_IPC_DEVICE_NONE) {
  92                 platform_data.devmode = wdtmode;
  93                 ipc_wdt_platform_device =
  94                         platform_device_register_data(NULL,
  95                                 KBUILD_MODNAME "_wdt", PLATFORM_DEVID_NONE,
  96                                 &platform_data,
  97                                 sizeof(struct simatic_ipc_platform));
  98                 if (IS_ERR(ipc_wdt_platform_device))
  99                         return PTR_ERR(ipc_wdt_platform_device);
 100
 101                 pr_debug("device=%s created\n",
 102                          ipc_wdt_platform_device->name);
 103         }
 104
 105         if (ledmode == SIMATIC_IPC_DEVICE_NONE &&
 106             wdtmode == SIMATIC_IPC_DEVICE_NONE) {
 107                 pr_warn("unsupported IPC detected, station id=%08x\n",
 108                         station_id);
 109                 return -EINVAL;
 110         }
 111
 112         return 0;
 113 }
 114
 115 static int __init simatic_ipc_init_module(void)
 116 {
 117         const struct dmi_system_id *match;
 118         u32 station_id;
 119         int err;
 120
 121         match = dmi_first_match(simatic_ipc_whitelist);
 122         if (!match)
 123                 return 0;
 124
 125         err = dmi_walk(simatic_ipc_find_dmi_entry_helper, &station_id);
 126
 127         if (err || station_id == SIMATIC_IPC_INVALID_STATION_ID) {
 128                 pr_warn("DMI entry %d not found\n", SIMATIC_IPC_DMI_ENTRY_OEM);
 129                 return 0;
 130         }
 131
 132         return register_platform_devices(station_id);
 133 }
 134
 135 static void __exit simatic_ipc_exit_module(void)
 136 {
 137         platform_device_unregister(ipc_led_platform_device);
 138         ipc_led_platform_device = NULL;
 139
 140         platform_device_unregister(ipc_wdt_platform_device);
 141         ipc_wdt_platform_device = NULL;
 142 }
 143
 144 module_init(simatic_ipc_init_module);
 145 module_exit(simatic_ipc_exit_module);
 146
 147 MODULE_LICENSE("GPL v2");
 148 MODULE_AUTHOR("Gerd Haeussler <[email protected]>");
 149 MODULE_ALIAS("dmi:*:svnSIEMENSAG:*");