1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Siemens SIMATIC IPC driver for LEDs 4 * 5 * Copyright (c) Siemens AG, 2018-2021 6 * 7 * Authors: 8 * Henning Schild <henning.schild@siemens.com> 9 * Jan Kiszka <jan.kiszka@siemens.com> 10 * Gerd Haeussler <gerd.haeussler.ext@siemens.com> 11 */ 12 13 #include <linux/ioport.h> 14 #include <linux/kernel.h> 15 #include <linux/leds.h> 16 #include <linux/module.h> 17 #include <linux/pci.h> 18 #include <linux/platform_data/x86/simatic-ipc-base.h> 19 #include <linux/platform_device.h> 20 #include <linux/sizes.h> 21 #include <linux/spinlock.h> 22 23 #define SIMATIC_IPC_LED_PORT_BASE 0x404E 24 25 struct simatic_ipc_led { 26 unsigned int value; /* mask for io */ 27 char *name; 28 struct led_classdev cdev; 29 }; 30 31 static struct simatic_ipc_led simatic_ipc_leds_io[] = { 32 {1 << 15, "green:" LED_FUNCTION_STATUS "-1" }, 33 {1 << 7, "yellow:" LED_FUNCTION_STATUS "-1" }, 34 {1 << 14, "red:" LED_FUNCTION_STATUS "-2" }, 35 {1 << 6, "yellow:" LED_FUNCTION_STATUS "-2" }, 36 {1 << 13, "red:" LED_FUNCTION_STATUS "-3" }, 37 {1 << 5, "yellow:" LED_FUNCTION_STATUS "-3" }, 38 { } 39 }; 40 41 static struct resource simatic_ipc_led_io_res = 42 DEFINE_RES_IO_NAMED(SIMATIC_IPC_LED_PORT_BASE, SZ_2, KBUILD_MODNAME); 43 44 static DEFINE_SPINLOCK(reg_lock); 45 46 static inline struct simatic_ipc_led *cdev_to_led(struct led_classdev *led_cd) 47 { 48 return container_of(led_cd, struct simatic_ipc_led, cdev); 49 } 50 51 static void simatic_ipc_led_set_io(struct led_classdev *led_cd, 52 enum led_brightness brightness) 53 { 54 struct simatic_ipc_led *led = cdev_to_led(led_cd); 55 unsigned long flags; 56 unsigned int val; 57 58 spin_lock_irqsave(®_lock, flags); 59 60 val = inw(SIMATIC_IPC_LED_PORT_BASE); 61 if (brightness == LED_OFF) 62 outw(val | led->value, SIMATIC_IPC_LED_PORT_BASE); 63 else 64 outw(val & ~led->value, SIMATIC_IPC_LED_PORT_BASE); 65 66 spin_unlock_irqrestore(®_lock, flags); 67 } 68 69 static enum led_brightness simatic_ipc_led_get_io(struct led_classdev *led_cd) 70 { 71 struct simatic_ipc_led *led = cdev_to_led(led_cd); 72 73 return inw(SIMATIC_IPC_LED_PORT_BASE) & led->value ? LED_OFF : led_cd->max_brightness; 74 } 75 76 static int simatic_ipc_leds_probe(struct platform_device *pdev) 77 { 78 const struct simatic_ipc_platform *plat = pdev->dev.platform_data; 79 struct device *dev = &pdev->dev; 80 struct simatic_ipc_led *ipcled; 81 struct led_classdev *cdev; 82 struct resource *res; 83 int err; 84 85 switch (plat->devmode) { 86 case SIMATIC_IPC_DEVICE_227D: 87 case SIMATIC_IPC_DEVICE_427E: 88 res = &simatic_ipc_led_io_res; 89 ipcled = simatic_ipc_leds_io; 90 /* on 227D the two bytes work the other way araound */ 91 if (plat->devmode == SIMATIC_IPC_DEVICE_227D) { 92 while (ipcled->value) { 93 ipcled->value = swab16(ipcled->value); 94 ipcled++; 95 } 96 ipcled = simatic_ipc_leds_io; 97 } 98 if (!devm_request_region(dev, res->start, resource_size(res), KBUILD_MODNAME)) { 99 dev_err(dev, "Unable to register IO resource at %pR\n", res); 100 return -EBUSY; 101 } 102 break; 103 default: 104 return -ENODEV; 105 } 106 107 while (ipcled->value) { 108 cdev = &ipcled->cdev; 109 cdev->brightness_set = simatic_ipc_led_set_io; 110 cdev->brightness_get = simatic_ipc_led_get_io; 111 cdev->max_brightness = LED_ON; 112 cdev->name = ipcled->name; 113 114 err = devm_led_classdev_register(dev, cdev); 115 if (err < 0) 116 return err; 117 ipcled++; 118 } 119 120 return 0; 121 } 122 123 static struct platform_driver simatic_ipc_led_driver = { 124 .probe = simatic_ipc_leds_probe, 125 .driver = { 126 .name = KBUILD_MODNAME, 127 } 128 }; 129 130 module_platform_driver(simatic_ipc_led_driver); 131 132 MODULE_LICENSE("GPL v2"); 133 MODULE_ALIAS("platform:" KBUILD_MODNAME); 134 MODULE_AUTHOR("Henning Schild <henning.schild@siemens.com>"); 135