1 /* apc - Driver implementation for power management functions
2 * of Aurora Personality Chip (APC) on SPARCstation-4/5 and
5 * Copyright (c) 2002 Eric Brower (ebrower@usa.net)
8 #include <linux/kernel.h>
10 #include <linux/errno.h>
11 #include <linux/init.h>
12 #include <linux/miscdevice.h>
17 #include <asm/oplib.h>
18 #include <asm/uaccess.h>
19 #include <asm/auxio.h>
24 * #define APC_DEBUG_LED
27 #define APC_MINOR MISC_DYNAMIC_MINOR
28 #define APC_OBPNAME "power-management"
29 #define APC_DEVNAME "apc"
31 volatile static u8 *regs;
32 static int apc_regsize;
33 static int apc_no_idle __initdata = 0;
35 #define apc_readb(offs) (sbus_readb(regs+offs))
36 #define apc_writeb(val, offs) (sbus_writeb(val, regs+offs))
38 /* Specify "apc=noidle" on the kernel command line to
39 * disable APC CPU standby support. Certain prototype
40 * systems (SPARCstation-Fox) do not play well with APC
41 * CPU idle, so disable this if your system has APC and
44 static int __init apc_setup(char *str)
46 if(!strncmp(str, "noidle", strlen("noidle"))) {
52 __setup("apc=", apc_setup);
55 * CPU idle callback function
56 * See .../arch/sparc/kernel/process.c
58 void apc_swift_idle(void)
61 set_auxio(0x00, AUXIO_LED);
64 apc_writeb(apc_readb(APC_IDLE_REG) | APC_IDLE_ON, APC_IDLE_REG);
67 set_auxio(AUXIO_LED, 0x00);
71 static inline void apc_free(void)
73 sbus_iounmap((unsigned long)regs, apc_regsize);
76 static int apc_open(struct inode *inode, struct file *f)
81 static int apc_release(struct inode *inode, struct file *f)
86 static int apc_ioctl(struct inode *inode, struct file *f,
87 unsigned int cmd, unsigned long arg)
93 if(put_user(apc_readb(APC_FANCTL_REG) & APC_REGMASK, (__u8*) arg)) {
98 if(put_user(apc_readb(APC_CPOWER_REG) & APC_REGMASK, (__u8*) arg)) {
103 if(put_user(apc_readb(APC_BPORT_REG) & APC_BPMASK, (__u8*) arg)) {
109 if(get_user(inarg, (__u8*) arg)) {
112 apc_writeb(inarg & APC_REGMASK, APC_FANCTL_REG);
115 if(get_user(inarg, (__u8*) arg)) {
118 apc_writeb(inarg & APC_REGMASK, APC_CPOWER_REG);
121 if(get_user(inarg, (__u8*) arg)) {
124 apc_writeb(inarg & APC_BPMASK, APC_BPORT_REG);
133 static struct file_operations apc_fops = {
136 .release = apc_release,
139 static struct miscdevice apc_miscdev = { APC_MINOR, APC_DEVNAME, &apc_fops };
141 static int __init apc_probe(void)
143 struct sbus_bus *sbus = NULL;
144 struct sbus_dev *sdev = NULL;
147 for_each_sbus(sbus) {
148 for_each_sbusdev(sdev, sbus) {
149 if (!strcmp(sdev->prom_name, APC_OBPNAME)) {
160 apc_regsize = sdev->reg_addrs[0].reg_size;
161 regs = (u8*) sbus_ioremap(&sdev->resource[0], 0,
162 apc_regsize, APC_OBPNAME);
164 printk(KERN_ERR "%s: unable to map registers\n", APC_DEVNAME);
168 iTmp = misc_register(&apc_miscdev);
170 printk(KERN_ERR "%s: unable to register device\n", APC_DEVNAME);
175 /* Assign power management IDLE handler */
177 pm_idle = apc_swift_idle;
179 printk(KERN_INFO "%s: power management initialized%s\n",
180 APC_DEVNAME, apc_no_idle ? " (CPU idle disabled)" : "");
184 /* This driver is not critical to the boot process
185 * and is easiest to ioremap when SBus is already
186 * initialized, so we install ourselves thusly:
188 __initcall(apc_probe);