1/* 2 * arch/arm/mach-u300/regulator.c 3 * 4 * Copyright (C) 2009 ST-Ericsson AB 5 * License terms: GNU General Public License (GPL) version 2 6 * Handle board-bound regulators and board power not related 7 * to any devices. 8 * Author: Linus Walleij <linus.walleij@stericsson.com> 9 */ 10#include <linux/device.h> 11#include <linux/signal.h> 12#include <linux/err.h> 13#include <linux/regulator/consumer.h> 14/* Those are just for writing in syscon */ 15#include <linux/io.h> 16#include <mach/hardware.h> 17#include <mach/syscon.h> 18 19/* 20 * Regulators that power the board and chip and which are 21 * not copuled to specific drivers are hogged in these 22 * instances. 23 */ 24static struct regulator *main_power_15; 25 26/* 27 * This function is used from pm.h to shut down the system by 28 * resetting all regulators in turn and then disable regulator 29 * LDO D (main power). 30 */ 31void u300_pm_poweroff(void) 32{ 33 sigset_t old, all; 34 35 sigfillset(&all); 36 if (!sigprocmask(SIG_BLOCK, &all, &old)) { 37 /* Disable LDO D to shut down the system */ 38 if (main_power_15) 39 regulator_disable(main_power_15); 40 else 41 pr_err("regulator not available to shut down system\n"); 42 (void) sigprocmask(SIG_SETMASK, &old, NULL); 43 } 44 return; 45} 46 47/* 48 * Hog the regulators needed to power up the board. 49 */ 50static int __init u300_init_boardpower(void) 51{ 52 int err; 53 u32 val; 54 55 pr_info("U300: setting up board power\n"); 56 main_power_15 = regulator_get(NULL, "vana15"); 57 if (IS_ERR(main_power_15)) { 58 pr_err("could not get vana15"); 59 return PTR_ERR(main_power_15); 60 } 61 err = regulator_enable(main_power_15); 62 if (err) { 63 pr_err("could not enable vana15\n"); 64 return err; 65 } 66 67 /* 68 * On U300 a special system controller register pulls up the DC 69 * until the vana15 (LDO D) regulator comes up. At this point, all 70 * regulators are set and we do not need power control via 71 * DC ON anymore. This function will likely be moved whenever 72 * the rest of the U300 power management is implemented. 73 */ 74 pr_info("U300: disable system controller pull-up\n"); 75 val = readw(U300_SYSCON_VBASE + U300_SYSCON_PMCR); 76 val &= ~U300_SYSCON_PMCR_DCON_ENABLE; 77 writew(val, U300_SYSCON_VBASE + U300_SYSCON_PMCR); 78 79 /* Register globally exported PM poweroff hook */ 80 pm_power_off = u300_pm_poweroff; 81 82 return 0; 83} 84 85/* 86 * So at module init time we hog the regulator! 87 */ 88module_init(u300_init_boardpower); 89