platform/x86/simatic-ipc.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Siemens SIMATIC IPC platform driver
0004  *
0005  * Copyright (c) Siemens AG, 2018-2021
0006  *
0007  * Authors:
0008  *  Henning Schild <henning.schild@siemens.com>
0009  *  Jan Kiszka <jan.kiszka@siemens.com>
0010  *  Gerd Haeussler <gerd.haeussler.ext@siemens.com>
0011  */
0012
0013 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
0014
0015 #include <linux/dmi.h>
0016 #include <linux/kernel.h>
0017 #include <linux/module.h>
0018 #include <linux/pci.h>
0019 #include <linux/platform_data/x86/simatic-ipc.h>
0020 #include <linux/platform_device.h>
0021
0022 static struct platform_device *ipc_led_platform_device;
0023 static struct platform_device *ipc_wdt_platform_device;
0024
0025 static const struct dmi_system_id simatic_ipc_whitelist[] = {
0026     {
0027         .matches = {
0028             DMI_MATCH(DMI_SYS_VENDOR, "SIEMENS AG"),
0029         },
0030     },
0031     {}
0032 };
0033
0034 static struct simatic_ipc_platform platform_data;
0035
0036 static struct {
0037     u32 station_id;
0038     u8 led_mode;
0039     u8 wdt_mode;
0040 } device_modes[] = {
0041     {SIMATIC_IPC_IPC127E, SIMATIC_IPC_DEVICE_127E, SIMATIC_IPC_DEVICE_NONE},
0042     {SIMATIC_IPC_IPC227D, SIMATIC_IPC_DEVICE_227D, SIMATIC_IPC_DEVICE_NONE},
0043     {SIMATIC_IPC_IPC227E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_227E},
0044     {SIMATIC_IPC_IPC277E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_227E},
0045     {SIMATIC_IPC_IPC427D, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_NONE},
0046     {SIMATIC_IPC_IPC427E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_427E},
0047     {SIMATIC_IPC_IPC477E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_427E},
0048 };
0049
0050 static int register_platform_devices(u32 station_id)
0051 {
0052     u8 ledmode = SIMATIC_IPC_DEVICE_NONE;
0053     u8 wdtmode = SIMATIC_IPC_DEVICE_NONE;
0054     char *pdevname = KBUILD_MODNAME "_leds";
0055     int i;
0056
0057     platform_data.devmode = SIMATIC_IPC_DEVICE_NONE;
0058
0059     for (i = 0; i < ARRAY_SIZE(device_modes); i++) {
0060         if (device_modes[i].station_id == station_id) {
0061             ledmode = device_modes[i].led_mode;
0062             wdtmode = device_modes[i].wdt_mode;
0063             break;
0064         }
0065     }
0066
0067     if (ledmode != SIMATIC_IPC_DEVICE_NONE) {
0068         if (ledmode == SIMATIC_IPC_DEVICE_127E)
0069             pdevname = KBUILD_MODNAME "_leds_gpio";
0070         platform_data.devmode = ledmode;
0071         ipc_led_platform_device =
0072             platform_device_register_data(NULL,
0073                 pdevname, PLATFORM_DEVID_NONE,
0074                 &platform_data,
0075                 sizeof(struct simatic_ipc_platform));
0076         if (IS_ERR(ipc_led_platform_device))
0077             return PTR_ERR(ipc_led_platform_device);
0078
0079         pr_debug("device=%s created\n",
0080              ipc_led_platform_device->name);
0081     }
0082
0083     if (wdtmode != SIMATIC_IPC_DEVICE_NONE) {
0084         platform_data.devmode = wdtmode;
0085         ipc_wdt_platform_device =
0086             platform_device_register_data(NULL,
0087                 KBUILD_MODNAME "_wdt", PLATFORM_DEVID_NONE,
0088                 &platform_data,
0089                 sizeof(struct simatic_ipc_platform));
0090         if (IS_ERR(ipc_wdt_platform_device))
0091             return PTR_ERR(ipc_wdt_platform_device);
0092
0093         pr_debug("device=%s created\n",
0094              ipc_wdt_platform_device->name);
0095     }
0096
0097     if (ledmode == SIMATIC_IPC_DEVICE_NONE &&
0098         wdtmode == SIMATIC_IPC_DEVICE_NONE) {
0099         pr_warn("unsupported IPC detected, station id=%08x\n",
0100             station_id);
0101         return -EINVAL;
0102     }
0103
0104     return 0;
0105 }
0106
0107 static int __init simatic_ipc_init_module(void)
0108 {
0109     const struct dmi_system_id *match;
0110     u32 station_id;
0111     int err;
0112
0113     match = dmi_first_match(simatic_ipc_whitelist);
0114     if (!match)
0115         return 0;
0116
0117     err = dmi_walk(simatic_ipc_find_dmi_entry_helper, &station_id);
0118
0119     if (err || station_id == SIMATIC_IPC_INVALID_STATION_ID) {
0120         pr_warn("DMI entry %d not found\n", SIMATIC_IPC_DMI_ENTRY_OEM);
0121         return 0;
0122     }
0123
0124     return register_platform_devices(station_id);
0125 }
0126
0127 static void __exit simatic_ipc_exit_module(void)
0128 {
0129     platform_device_unregister(ipc_led_platform_device);
0130     ipc_led_platform_device = NULL;
0131
0132     platform_device_unregister(ipc_wdt_platform_device);
0133     ipc_wdt_platform_device = NULL;
0134 }
0135
0136 module_init(simatic_ipc_init_module);
0137 module_exit(simatic_ipc_exit_module);
0138
0139 MODULE_LICENSE("GPL v2");
0140 MODULE_AUTHOR("Gerd Haeussler <gerd.haeussler.ext@siemens.com>");
0141 MODULE_ALIAS("dmi:*:svnSIEMENSAG:*");