1 /* pmc - Driver implementation for power management functions 2 * of Power Management Controller (PMC) on SPARCstation-Voyager. 3 * 4 * Copyright (c) 2002 Eric Brower (ebrower@usa.net) 5 */ 6 7 #include <linux/kernel.h> 8 #include <linux/fs.h> 9 #include <linux/errno.h> 10 #include <linux/init.h> 11 #include <linux/pm.h> 12 #include <linux/of.h> 13 #include <linux/of_device.h> 14 15 #include <asm/io.h> 16 #include <asm/oplib.h> 17 #include <asm/uaccess.h> 18 #include <asm/auxio.h> 19 20 /* Debug 21 * 22 * #define PMC_DEBUG_LED 23 * #define PMC_NO_IDLE 24 */ 25 26 #define PMC_OBPNAME "SUNW,pmc" 27 #define PMC_DEVNAME "pmc" 28 29 #define PMC_IDLE_REG 0x00 30 #define PMC_IDLE_ON 0x01 31 32 static u8 __iomem *regs; 33 34 #define pmc_readb(offs) (sbus_readb(regs+offs)) 35 #define pmc_writeb(val, offs) (sbus_writeb(val, regs+offs)) 36 37 /* 38 * CPU idle callback function 39 * See .../arch/sparc/kernel/process.c 40 */ 41 static void pmc_swift_idle(void) 42 { 43 #ifdef PMC_DEBUG_LED 44 set_auxio(0x00, AUXIO_LED); 45 #endif 46 47 pmc_writeb(pmc_readb(PMC_IDLE_REG) | PMC_IDLE_ON, PMC_IDLE_REG); 48 49 #ifdef PMC_DEBUG_LED 50 set_auxio(AUXIO_LED, 0x00); 51 #endif 52 } 53 54 static int __devinit pmc_probe(struct platform_device *op) 55 { 56 regs = of_ioremap(&op->resource[0], 0, 57 resource_size(&op->resource[0]), PMC_OBPNAME); 58 if (!regs) { 59 printk(KERN_ERR "%s: unable to map registers\n", PMC_DEVNAME); 60 return -ENODEV; 61 } 62 63 #ifndef PMC_NO_IDLE 64 /* Assign power management IDLE handler */ 65 pm_idle = pmc_swift_idle; 66 #endif 67 68 printk(KERN_INFO "%s: power management initialized\n", PMC_DEVNAME); 69 return 0; 70 } 71 72 static struct of_device_id pmc_match[] = { 73 { 74 .name = PMC_OBPNAME, 75 }, 76 {}, 77 }; 78 MODULE_DEVICE_TABLE(of, pmc_match); 79 80 static struct platform_driver pmc_driver = { 81 .driver = { 82 .name = "pmc", 83 .owner = THIS_MODULE, 84 .of_match_table = pmc_match, 85 }, 86 .probe = pmc_probe, 87 }; 88 89 static int __init pmc_init(void) 90 { 91 return platform_driver_register(&pmc_driver); 92 } 93 94 /* This driver is not critical to the boot process 95 * and is easiest to ioremap when SBus is already 96 * initialized, so we install ourselves thusly: 97 */ 98 __initcall(pmc_init); 99