| Linus Walleij | 3d81277 | 2009-09-23 15:45:02 +0100 | [diff] [blame] | 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 | */ |
| 24 | static 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 | */ |
| 31 | void 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 | */ |
| 50 | static 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 | */ |
| 88 | module_init(u300_init_boardpower); |