diff options
Diffstat (limited to 'drivers/platform/x86/simatic-ipc.c')
| -rw-r--r-- | drivers/platform/x86/simatic-ipc.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/drivers/platform/x86/simatic-ipc.c b/drivers/platform/x86/simatic-ipc.c new file mode 100644 index 000000000000..b599cda5ba3c --- /dev/null +++ b/drivers/platform/x86/simatic-ipc.c @@ -0,0 +1,176 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Siemens SIMATIC IPC platform driver + * + * Copyright (c) Siemens AG, 2018-2021 + * + * Authors: + * Henning Schild <henning.schild@siemens.com> + * Jan Kiszka <jan.kiszka@siemens.com> + * Gerd Haeussler <gerd.haeussler.ext@siemens.com> + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/dmi.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/platform_data/x86/simatic-ipc.h> +#include <linux/platform_device.h> + +static struct platform_device *ipc_led_platform_device; +static struct platform_device *ipc_wdt_platform_device; + +static const struct dmi_system_id simatic_ipc_whitelist[] = { + { + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "SIEMENS AG"), + }, + }, + {} +}; + +static struct simatic_ipc_platform platform_data; + +static struct { + u32 station_id; + u8 led_mode; + u8 wdt_mode; +} device_modes[] = { + {SIMATIC_IPC_IPC127E, SIMATIC_IPC_DEVICE_127E, SIMATIC_IPC_DEVICE_NONE}, + {SIMATIC_IPC_IPC227D, SIMATIC_IPC_DEVICE_227D, SIMATIC_IPC_DEVICE_NONE}, + {SIMATIC_IPC_IPC227E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_227E}, + {SIMATIC_IPC_IPC277E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_227E}, + {SIMATIC_IPC_IPC427D, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_NONE}, + {SIMATIC_IPC_IPC427E, SIMATIC_IPC_DEVICE_427E, SIMATIC_IPC_DEVICE_427E}, + {SIMATIC_IPC_IPC477E, SIMATIC_IPC_DEVICE_NONE, SIMATIC_IPC_DEVICE_427E}, +}; + +static int register_platform_devices(u32 station_id) +{ + u8 ledmode = SIMATIC_IPC_DEVICE_NONE; + u8 wdtmode = SIMATIC_IPC_DEVICE_NONE; + int i; + + platform_data.devmode = SIMATIC_IPC_DEVICE_NONE; + + for (i = 0; i < ARRAY_SIZE(device_modes); i++) { + if (device_modes[i].station_id == station_id) { + ledmode = device_modes[i].led_mode; + wdtmode = device_modes[i].wdt_mode; + break; + } + } + + if (ledmode != SIMATIC_IPC_DEVICE_NONE) { + platform_data.devmode = ledmode; + ipc_led_platform_device = + platform_device_register_data(NULL, + KBUILD_MODNAME "_leds", PLATFORM_DEVID_NONE, + &platform_data, + sizeof(struct simatic_ipc_platform)); + if (IS_ERR(ipc_led_platform_device)) + return PTR_ERR(ipc_led_platform_device); + + pr_debug("device=%s created\n", + ipc_led_platform_device->name); + } + + if (wdtmode != SIMATIC_IPC_DEVICE_NONE) { + platform_data.devmode = wdtmode; + ipc_wdt_platform_device = + platform_device_register_data(NULL, + KBUILD_MODNAME "_wdt", PLATFORM_DEVID_NONE, + &platform_data, + sizeof(struct simatic_ipc_platform)); + if (IS_ERR(ipc_wdt_platform_device)) + return PTR_ERR(ipc_wdt_platform_device); + + pr_debug("device=%s created\n", + ipc_wdt_platform_device->name); + } + + if (ledmode == SIMATIC_IPC_DEVICE_NONE && + wdtmode == SIMATIC_IPC_DEVICE_NONE) { + pr_warn("unsupported IPC detected, station id=%08x\n", + station_id); + return -EINVAL; + } + + return 0; +} + +/* FIXME: this should eventually be done with generic P2SB discovery code + * the individual drivers for watchdogs and LEDs access memory that implements + * GPIO, but pinctrl will not come up because of missing ACPI entries + * + * While there is no conflict a cleaner solution would be to somehow bring up + * pinctrl even with these ACPI entries missing, and base the drivers on pinctrl. + * After which the following function could be dropped, together with the code + * poking the memory. + */ +/* + * Get membase address from PCI, used in leds and wdt module. Here we read + * the bar0. The final address calculation is done in the appropriate modules + */ +u32 simatic_ipc_get_membase0(unsigned int p2sb) +{ + struct pci_bus *bus; + u32 bar0 = 0; + /* + * The GPIO memory is in bar0 of the hidden P2SB device. + * Unhide the device to have a quick look at it, before we hide it + * again. + * Also grab the pci rescan lock so that device does not get discovered + * and remapped while it is visible. + * This code is inspired by drivers/mfd/lpc_ich.c + */ + bus = pci_find_bus(0, 0); + pci_lock_rescan_remove(); + pci_bus_write_config_byte(bus, p2sb, 0xE1, 0x0); + pci_bus_read_config_dword(bus, p2sb, PCI_BASE_ADDRESS_0, &bar0); + + bar0 &= ~0xf; + pci_bus_write_config_byte(bus, p2sb, 0xE1, 0x1); + pci_unlock_rescan_remove(); + + return bar0; +} +EXPORT_SYMBOL(simatic_ipc_get_membase0); + +static int __init simatic_ipc_init_module(void) +{ + const struct dmi_system_id *match; + u32 station_id; + int err; + + match = dmi_first_match(simatic_ipc_whitelist); + if (!match) + return 0; + + err = dmi_walk(simatic_ipc_find_dmi_entry_helper, &station_id); + + if (err || station_id == SIMATIC_IPC_INVALID_STATION_ID) { + pr_warn("DMI entry %d not found\n", SIMATIC_IPC_DMI_ENTRY_OEM); + return 0; + } + + return register_platform_devices(station_id); +} + +static void __exit simatic_ipc_exit_module(void) +{ + platform_device_unregister(ipc_led_platform_device); + ipc_led_platform_device = NULL; + + platform_device_unregister(ipc_wdt_platform_device); + ipc_wdt_platform_device = NULL; +} + +module_init(simatic_ipc_init_module); +module_exit(simatic_ipc_exit_module); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Gerd Haeussler <gerd.haeussler.ext@siemens.com>"); +MODULE_ALIAS("dmi:*:svnSIEMENSAG:*"); |