Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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/miscdevice.h> |
| 12 | #include <linux/pm.h> |
| 13 | |
| 14 | #include <asm/io.h> |
| 15 | #include <asm/sbus.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_MINOR MISC_DYNAMIC_MINOR |
| 27 | #define PMC_OBPNAME "SUNW,pmc" |
| 28 | #define PMC_DEVNAME "pmc" |
| 29 | |
| 30 | #define PMC_IDLE_REG 0x00 |
| 31 | #define PMC_IDLE_ON 0x01 |
| 32 | |
| 33 | volatile static u8 __iomem *regs; |
| 34 | static int pmc_regsize; |
| 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 | 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 inline void pmc_free(void) |
| 57 | { |
| 58 | sbus_iounmap(regs, pmc_regsize); |
| 59 | } |
| 60 | |
| 61 | static int __init pmc_probe(void) |
| 62 | { |
| 63 | struct sbus_bus *sbus = NULL; |
| 64 | struct sbus_dev *sdev = NULL; |
| 65 | for_each_sbus(sbus) { |
| 66 | for_each_sbusdev(sdev, sbus) { |
| 67 | if (!strcmp(sdev->prom_name, PMC_OBPNAME)) { |
| 68 | goto sbus_done; |
| 69 | } |
| 70 | } |
| 71 | } |
| 72 | |
| 73 | sbus_done: |
| 74 | if (!sdev) { |
| 75 | return -ENODEV; |
| 76 | } |
| 77 | |
| 78 | pmc_regsize = sdev->reg_addrs[0].reg_size; |
| 79 | regs = sbus_ioremap(&sdev->resource[0], 0, |
| 80 | pmc_regsize, PMC_OBPNAME); |
| 81 | if (!regs) { |
| 82 | printk(KERN_ERR "%s: unable to map registers\n", PMC_DEVNAME); |
| 83 | return -ENODEV; |
| 84 | } |
| 85 | |
| 86 | #ifndef PMC_NO_IDLE |
| 87 | /* Assign power management IDLE handler */ |
| 88 | pm_idle = pmc_swift_idle; |
| 89 | #endif |
| 90 | |
| 91 | printk(KERN_INFO "%s: power management initialized\n", PMC_DEVNAME); |
| 92 | return 0; |
| 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_probe); |