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 #include <linux/module.h> 15 16 #include <asm/io.h> 17 #include <asm/oplib.h> 18 #include <asm/uaccess.h> 19 #include <asm/auxio.h> 20 #include <asm/processor.h> 21 22 /* Debug 23 * 24 * #define PMC_DEBUG_LED 25 * #define PMC_NO_IDLE 26 */ 27 28 #define PMC_OBPNAME "SUNW,pmc" 29 #define PMC_DEVNAME "pmc" 30 31 #define PMC_IDLE_REG 0x00 32 #define PMC_IDLE_ON 0x01 33 34 static u8 __iomem *regs; 35 36 #define pmc_readb(offs) (sbus_readb(regs+offs)) 37 #define pmc_writeb(val, offs) (sbus_writeb(val, regs+offs)) 38 39 /* 40 * CPU idle callback function 41 * See .../arch/sparc/kernel/process.c 42 */ 43 static void pmc_swift_idle(void) 44 { 45 #ifdef PMC_DEBUG_LED 46 set_auxio(0x00, AUXIO_LED); 47 #endif 48 49 pmc_writeb(pmc_readb(PMC_IDLE_REG) | PMC_IDLE_ON, PMC_IDLE_REG); 50 51 #ifdef PMC_DEBUG_LED 52 set_auxio(AUXIO_LED, 0x00); 53 #endif 54 } 55 56 static int pmc_probe(struct platform_device *op) 57 { 58 regs = of_ioremap(&op->resource[0], 0, 59 resource_size(&op->resource[0]), PMC_OBPNAME); 60 if (!regs) { 61 printk(KERN_ERR "%s: unable to map registers\n", PMC_DEVNAME); 62 return -ENODEV; 63 } 64 65 #ifndef PMC_NO_IDLE 66 /* Assign power management IDLE handler */ 67 sparc_idle = pmc_swift_idle; 68 #endif 69 70 printk(KERN_INFO "%s: power management initialized\n", PMC_DEVNAME); 71 return 0; 72 } 73 74 static struct of_device_id pmc_match[] = { 75 { 76 .name = PMC_OBPNAME, 77 }, 78 {}, 79 }; 80 MODULE_DEVICE_TABLE(of, pmc_match); 81 82 static struct platform_driver pmc_driver = { 83 .driver = { 84 .name = "pmc", 85 .of_match_table = pmc_match, 86 }, 87 .probe = pmc_probe, 88 }; 89 90 static int __init pmc_init(void) 91 { 92 return platform_driver_register(&pmc_driver); 93 } 94 95 /* This driver is not critical to the boot process 96 * and is easiest to ioremap when SBus is already 97 * initialized, so we install ourselves thusly: 98 */ 99 __initcall(pmc_init); 100