1401e9093SPaul Mundt /* 2401e9093SPaul Mundt * Generic heartbeat driver for regular LED banks 3401e9093SPaul Mundt * 4401e9093SPaul Mundt * Copyright (C) 2007 Paul Mundt 5401e9093SPaul Mundt * 6401e9093SPaul Mundt * Most SH reference boards include a number of individual LEDs that can 7401e9093SPaul Mundt * be independently controlled (either via a pre-defined hardware 8401e9093SPaul Mundt * function or via the LED class, if desired -- the hardware tends to 9401e9093SPaul Mundt * encapsulate some of the same "triggers" that the LED class supports, 10401e9093SPaul Mundt * so there's not too much value in it). 11401e9093SPaul Mundt * 12401e9093SPaul Mundt * Additionally, most of these boards also have a LED bank that we've 13401e9093SPaul Mundt * traditionally used for strobing the load average. This use case is 14401e9093SPaul Mundt * handled by this driver, rather than giving each LED bit position its 15401e9093SPaul Mundt * own struct device. 16401e9093SPaul Mundt * 17401e9093SPaul Mundt * This file is subject to the terms and conditions of the GNU General Public 18401e9093SPaul Mundt * License. See the file "COPYING" in the main directory of this archive 19401e9093SPaul Mundt * for more details. 20401e9093SPaul Mundt */ 21401e9093SPaul Mundt #include <linux/init.h> 22401e9093SPaul Mundt #include <linux/module.h> 23401e9093SPaul Mundt #include <linux/platform_device.h> 24401e9093SPaul Mundt #include <linux/sched.h> 25401e9093SPaul Mundt #include <linux/timer.h> 26401e9093SPaul Mundt #include <linux/io.h> 278786c952SPaul Mundt #include <asm/heartbeat.h> 28401e9093SPaul Mundt 29401e9093SPaul Mundt #define DRV_NAME "heartbeat" 308786c952SPaul Mundt #define DRV_VERSION "0.1.1" 31401e9093SPaul Mundt 328786c952SPaul Mundt static unsigned char default_bit_pos[] = { 0, 1, 2, 3, 4, 5, 6, 7 }; 338786c952SPaul Mundt 348786c952SPaul Mundt static inline void heartbeat_toggle_bit(struct heartbeat_data *hd, 358786c952SPaul Mundt unsigned bit, unsigned int inverted) 368786c952SPaul Mundt { 378786c952SPaul Mundt unsigned int new; 388786c952SPaul Mundt 398786c952SPaul Mundt new = (1 << hd->bit_pos[bit]); 408786c952SPaul Mundt if (inverted) 418786c952SPaul Mundt new = ~new; 428786c952SPaul Mundt 43e174d130SKuninori Morimoto new &= hd->mask; 44e174d130SKuninori Morimoto 458786c952SPaul Mundt switch (hd->regsize) { 468786c952SPaul Mundt case 32: 47e174d130SKuninori Morimoto new |= ioread32(hd->base) & ~hd->mask; 488786c952SPaul Mundt iowrite32(new, hd->base); 498786c952SPaul Mundt break; 508786c952SPaul Mundt case 16: 51e174d130SKuninori Morimoto new |= ioread16(hd->base) & ~hd->mask; 528786c952SPaul Mundt iowrite16(new, hd->base); 538786c952SPaul Mundt break; 548786c952SPaul Mundt default: 55e174d130SKuninori Morimoto new |= ioread8(hd->base) & ~hd->mask; 568786c952SPaul Mundt iowrite8(new, hd->base); 578786c952SPaul Mundt break; 588786c952SPaul Mundt } 598786c952SPaul Mundt } 60401e9093SPaul Mundt 61401e9093SPaul Mundt static void heartbeat_timer(unsigned long data) 62401e9093SPaul Mundt { 63401e9093SPaul Mundt struct heartbeat_data *hd = (struct heartbeat_data *)data; 64401e9093SPaul Mundt static unsigned bit = 0, up = 1; 65401e9093SPaul Mundt 668786c952SPaul Mundt heartbeat_toggle_bit(hd, bit, hd->flags & HEARTBEAT_INVERTED); 678786c952SPaul Mundt 68f6072896STakashi YOSHII bit += up; 698786c952SPaul Mundt if ((bit == 0) || (bit == (hd->nr_bits)-1)) 70f6072896STakashi YOSHII up = -up; 71401e9093SPaul Mundt 72401e9093SPaul Mundt mod_timer(&hd->timer, jiffies + (110 - ((300 << FSHIFT) / 73401e9093SPaul Mundt ((avenrun[0] / 5) + (3 << FSHIFT))))); 74401e9093SPaul Mundt } 75401e9093SPaul Mundt 76401e9093SPaul Mundt static int heartbeat_drv_probe(struct platform_device *pdev) 77401e9093SPaul Mundt { 78401e9093SPaul Mundt struct resource *res; 79401e9093SPaul Mundt struct heartbeat_data *hd; 80e174d130SKuninori Morimoto int i; 81401e9093SPaul Mundt 82401e9093SPaul Mundt if (unlikely(pdev->num_resources != 1)) { 83401e9093SPaul Mundt dev_err(&pdev->dev, "invalid number of resources\n"); 84401e9093SPaul Mundt return -EINVAL; 85401e9093SPaul Mundt } 86401e9093SPaul Mundt 87401e9093SPaul Mundt res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 88401e9093SPaul Mundt if (unlikely(res == NULL)) { 89401e9093SPaul Mundt dev_err(&pdev->dev, "invalid resource\n"); 90401e9093SPaul Mundt return -EINVAL; 91401e9093SPaul Mundt } 92401e9093SPaul Mundt 938786c952SPaul Mundt if (pdev->dev.platform_data) { 948786c952SPaul Mundt hd = pdev->dev.platform_data; 958786c952SPaul Mundt } else { 968786c952SPaul Mundt hd = kzalloc(sizeof(struct heartbeat_data), GFP_KERNEL); 97401e9093SPaul Mundt if (unlikely(!hd)) 98401e9093SPaul Mundt return -ENOMEM; 99401e9093SPaul Mundt } 100401e9093SPaul Mundt 1018786c952SPaul Mundt hd->base = ioremap_nocache(res->start, res->end - res->start + 1); 1021de83e94SRoel Kluin if (unlikely(!hd->base)) { 1038786c952SPaul Mundt dev_err(&pdev->dev, "ioremap failed\n"); 1048786c952SPaul Mundt 1058786c952SPaul Mundt if (!pdev->dev.platform_data) 1068786c952SPaul Mundt kfree(hd); 1078786c952SPaul Mundt 1088786c952SPaul Mundt return -ENXIO; 1098786c952SPaul Mundt } 1108786c952SPaul Mundt 1118786c952SPaul Mundt if (!hd->nr_bits) { 1128786c952SPaul Mundt hd->bit_pos = default_bit_pos; 1138786c952SPaul Mundt hd->nr_bits = ARRAY_SIZE(default_bit_pos); 1148786c952SPaul Mundt } 1158786c952SPaul Mundt 116e174d130SKuninori Morimoto hd->mask = 0; 117e174d130SKuninori Morimoto for (i = 0; i < hd->nr_bits; i++) 118e174d130SKuninori Morimoto hd->mask |= (1 << hd->bit_pos[i]); 119e174d130SKuninori Morimoto 1208786c952SPaul Mundt if (!hd->regsize) 1218786c952SPaul Mundt hd->regsize = 8; /* default access size */ 122401e9093SPaul Mundt 123401e9093SPaul Mundt setup_timer(&hd->timer, heartbeat_timer, (unsigned long)hd); 124401e9093SPaul Mundt platform_set_drvdata(pdev, hd); 125401e9093SPaul Mundt 126401e9093SPaul Mundt return mod_timer(&hd->timer, jiffies + 1); 127401e9093SPaul Mundt } 128401e9093SPaul Mundt 129401e9093SPaul Mundt static int heartbeat_drv_remove(struct platform_device *pdev) 130401e9093SPaul Mundt { 131401e9093SPaul Mundt struct heartbeat_data *hd = platform_get_drvdata(pdev); 132401e9093SPaul Mundt 133401e9093SPaul Mundt del_timer_sync(&hd->timer); 1348786c952SPaul Mundt iounmap(hd->base); 135401e9093SPaul Mundt 136401e9093SPaul Mundt platform_set_drvdata(pdev, NULL); 137401e9093SPaul Mundt 1388786c952SPaul Mundt if (!pdev->dev.platform_data) 139401e9093SPaul Mundt kfree(hd); 140401e9093SPaul Mundt 141401e9093SPaul Mundt return 0; 142401e9093SPaul Mundt } 143401e9093SPaul Mundt 144401e9093SPaul Mundt static struct platform_driver heartbeat_driver = { 145401e9093SPaul Mundt .probe = heartbeat_drv_probe, 146401e9093SPaul Mundt .remove = heartbeat_drv_remove, 147401e9093SPaul Mundt .driver = { 148401e9093SPaul Mundt .name = DRV_NAME, 149401e9093SPaul Mundt }, 150401e9093SPaul Mundt }; 151401e9093SPaul Mundt 152401e9093SPaul Mundt static int __init heartbeat_init(void) 153401e9093SPaul Mundt { 154401e9093SPaul Mundt printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION); 155401e9093SPaul Mundt return platform_driver_register(&heartbeat_driver); 156401e9093SPaul Mundt } 157401e9093SPaul Mundt 158401e9093SPaul Mundt static void __exit heartbeat_exit(void) 159401e9093SPaul Mundt { 160401e9093SPaul Mundt platform_driver_unregister(&heartbeat_driver); 161401e9093SPaul Mundt } 162401e9093SPaul Mundt module_init(heartbeat_init); 163401e9093SPaul Mundt module_exit(heartbeat_exit); 164401e9093SPaul Mundt 165401e9093SPaul Mundt MODULE_VERSION(DRV_VERSION); 166401e9093SPaul Mundt MODULE_AUTHOR("Paul Mundt"); 167401e9093SPaul Mundt MODULE_LICENSE("GPL v2"); 168