| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* pmc - Driver implementation for power management functions |
| 3 | * of Power Management Controller (PMC) on SPARCstation-Voyager. |
| 4 | * |
| 5 | * Copyright (c) 2002 Eric Brower (ebrower@usa.net) |
| 6 | */ |
| 7 | |
| 8 | #include <linux/kernel.h> |
| 9 | #include <linux/fs.h> |
| 10 | #include <linux/errno.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/pm.h> |
| 13 | #include <linux/of.h> |
| 14 | #include <linux/of_device.h> |
| 15 | #include <linux/module.h> |
| 16 | |
| 17 | #include <asm/io.h> |
| 18 | #include <asm/oplib.h> |
| 19 | #include <linux/uaccess.h> |
| 20 | #include <asm/auxio.h> |
| 21 | #include <asm/processor.h> |
| 22 | |
| 23 | /* Debug |
| 24 | * |
| 25 | * #define PMC_DEBUG_LED |
| 26 | * #define PMC_NO_IDLE |
| 27 | */ |
| 28 | |
| 29 | #define PMC_OBPNAME "SUNW,pmc" |
| 30 | #define PMC_DEVNAME "pmc" |
| 31 | |
| 32 | #define PMC_IDLE_REG 0x00 |
| 33 | #define PMC_IDLE_ON 0x01 |
| 34 | |
| 35 | static u8 __iomem *regs; |
| 36 | |
| 37 | #define pmc_readb(offs) (sbus_readb(regs+offs)) |
| 38 | #define pmc_writeb(val, offs) (sbus_writeb(val, regs+offs)) |
| 39 | |
| 40 | /* |
| 41 | * CPU idle callback function |
| 42 | * See .../arch/sparc/kernel/process.c |
| 43 | */ |
| 44 | static void pmc_swift_idle(void) |
| 45 | { |
| 46 | #ifdef PMC_DEBUG_LED |
| 47 | set_auxio(0x00, AUXIO_LED); |
| 48 | #endif |
| 49 | |
| 50 | pmc_writeb(pmc_readb(PMC_IDLE_REG) | PMC_IDLE_ON, PMC_IDLE_REG); |
| 51 | |
| 52 | #ifdef PMC_DEBUG_LED |
| 53 | set_auxio(AUXIO_LED, 0x00); |
| 54 | #endif |
| 55 | } |
| 56 | |
| 57 | static int pmc_probe(struct platform_device *op) |
| 58 | { |
| 59 | regs = of_ioremap(&op->resource[0], 0, |
| 60 | resource_size(&op->resource[0]), PMC_OBPNAME); |
| 61 | if (!regs) { |
| 62 | printk(KERN_ERR "%s: unable to map registers\n", PMC_DEVNAME); |
| 63 | return -ENODEV; |
| 64 | } |
| 65 | |
| 66 | #ifndef PMC_NO_IDLE |
| 67 | /* Assign power management IDLE handler */ |
| 68 | sparc_idle = pmc_swift_idle; |
| 69 | #endif |
| 70 | |
| 71 | printk(KERN_INFO "%s: power management initialized\n", PMC_DEVNAME); |
| 72 | return 0; |
| 73 | } |
| 74 | |
| 75 | static const struct of_device_id pmc_match[] = { |
| 76 | { |
| 77 | .name = PMC_OBPNAME, |
| 78 | }, |
| 79 | {}, |
| 80 | }; |
| 81 | MODULE_DEVICE_TABLE(of, pmc_match); |
| 82 | |
| 83 | static struct platform_driver pmc_driver = { |
| 84 | .driver = { |
| 85 | .name = "pmc", |
| 86 | .of_match_table = pmc_match, |
| 87 | }, |
| 88 | .probe = pmc_probe, |
| 89 | }; |
| 90 | |
| 91 | static int __init pmc_init(void) |
| 92 | { |
| 93 | return platform_driver_register(&pmc_driver); |
| 94 | } |
| 95 | |
| 96 | /* This driver is not critical to the boot process |
| 97 | * and is easiest to ioremap when SBus is already |
| 98 | * initialized, so we install ourselves thusly: |
| 99 | */ |
| 100 | __initcall(pmc_init); |