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_IPC277E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_227E},
  45         {SIMATIC_IPC_IPC427D, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_NONE},
  46         {SIMATIC_IPC_IPC427E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_427E},
  47         {SIMATIC_IPC_IPC477E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_427E},
  48 };
  49
  50 static int register_platform_devices(u32 station_id)
  51 {
  52         u8 ledmode = SIMATIC_IPC_DEVICE_NONE;
  53         u8 wdtmode = SIMATIC_IPC_DEVICE_NONE;
  54         char *pdevname = KBUILD_MODNAME "_leds";
  55         int i;
  56
  57         platform_data.devmode = SIMATIC_IPC_DEVICE_NONE;
  58
  59         for (i = 0; i < ARRAY_SIZE(device_modes); i++) {
  60                 if (device_modes[i].station_id == station_id) {
  61                         ledmode = device_modes[i].led_mode;
  62                         wdtmode = device_modes[i].wdt_mode;
  63                         break;
  64                 }
  65         }
  66
  67         if (ledmode != SIMATIC_IPC_DEVICE_NONE) {
  68                 if (ledmode == SIMATIC_IPC_DEVICE_127E)
  69                         pdevname = KBUILD_MODNAME "_leds_gpio";
  70                 platform_data.devmode = ledmode;
  71                 ipc_led_platform_device =
  72                         platform_device_register_data(NULL,
  73                                 pdevname, PLATFORM_DEVID_NONE,
  74                                 &platform_data,
  75                                 sizeof(struct simatic_ipc_platform));
  76                 if (IS_ERR(ipc_led_platform_device))
  77                         return PTR_ERR(ipc_led_platform_device);
  78
  79                 pr_debug("device=%s created\n",
  80                          ipc_led_platform_device->name);
  81         }
  82
  83         if (wdtmode != SIMATIC_IPC_DEVICE_NONE) {
  84                 platform_data.devmode = wdtmode;
  85                 ipc_wdt_platform_device =
  86                         platform_device_register_data(NULL,
  87                                 KBUILD_MODNAME "_wdt", PLATFORM_DEVID_NONE,
  88                                 &platform_data,
  89                                 sizeof(struct simatic_ipc_platform));
  90                 if (IS_ERR(ipc_wdt_platform_device))
  91                         return PTR_ERR(ipc_wdt_platform_device);
  92
  93                 pr_debug("device=%s created\n",
  94                          ipc_wdt_platform_device->name);
  95         }
  96
  97         if (ledmode == SIMATIC_IPC_DEVICE_NONE &&
  98             wdtmode == SIMATIC_IPC_DEVICE_NONE) {
  99                 pr_warn("unsupported IPC detected, station id=%08x\n",
 100                         station_id);
 101                 return -EINVAL;
 102         }
 103
 104         return 0;
 105 }
 106
 107 static int __init simatic_ipc_init_module(void)
 108 {
 109         const struct dmi_system_id *match;
 110         u32 station_id;
 111         int err;
 112
 113         match = dmi_first_match(simatic_ipc_whitelist);
 114         if (!match)
 115                 return 0;
 116
 117         err = dmi_walk(simatic_ipc_find_dmi_entry_helper, &station_id);
 118
 119         if (err || station_id == SIMATIC_IPC_INVALID_STATION_ID) {
 120                 pr_warn("DMI entry %d not found\n", SIMATIC_IPC_DMI_ENTRY_OEM);
 121                 return 0;
 122         }
 123
 124         return register_platform_devices(station_id);
 125 }
 126
 127 static void __exit simatic_ipc_exit_module(void)
 128 {
 129         platform_device_unregister(ipc_led_platform_device);
 130         ipc_led_platform_device = NULL;
 131
 132         platform_device_unregister(ipc_wdt_platform_device);
 133         ipc_wdt_platform_device = NULL;
 134 }
 135
 136 module_init(simatic_ipc_init_module);
 137 module_exit(simatic_ipc_exit_module);
 138
 139 MODULE_LICENSE("GPL v2");
 140 MODULE_AUTHOR("Gerd Haeussler <[email protected]>");
 141 MODULE_ALIAS("dmi:*:svnSIEMENSAG:*");