diff options
Diffstat (limited to 'arch/arm/mach-u300/regulator.c')
-rw-r--r-- | arch/arm/mach-u300/regulator.c | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/arch/arm/mach-u300/regulator.c b/arch/arm/mach-u300/regulator.c new file mode 100644 index 00000000000..9c53f01c62e --- /dev/null +++ b/arch/arm/mach-u300/regulator.c @@ -0,0 +1,88 @@ +/* + * arch/arm/mach-u300/regulator.c + * + * Copyright (C) 2009 ST-Ericsson AB + * License terms: GNU General Public License (GPL) version 2 + * Handle board-bound regulators and board power not related + * to any devices. + * Author: Linus Walleij <linus.walleij@stericsson.com> + */ +#include <linux/device.h> +#include <linux/signal.h> +#include <linux/err.h> +#include <linux/regulator/consumer.h> +/* Those are just for writing in syscon */ +#include <linux/io.h> +#include <mach/hardware.h> +#include <mach/syscon.h> + +/* + * Regulators that power the board and chip and which are + * not copuled to specific drivers are hogged in these + * instances. + */ +static struct regulator *main_power_15; + +/* + * This function is used from pm.h to shut down the system by + * resetting all regulators in turn and then disable regulator + * LDO D (main power). + */ +void u300_pm_poweroff(void) +{ + sigset_t old, all; + + sigfillset(&all); + if (!sigprocmask(SIG_BLOCK, &all, &old)) { + /* Disable LDO D to shut down the system */ + if (main_power_15) + regulator_disable(main_power_15); + else + pr_err("regulator not available to shut down system\n"); + (void) sigprocmask(SIG_SETMASK, &old, NULL); + } + return; +} + +/* + * Hog the regulators needed to power up the board. + */ +static int __init u300_init_boardpower(void) +{ + int err; + u32 val; + + pr_info("U300: setting up board power\n"); + main_power_15 = regulator_get(NULL, "vana15"); + if (IS_ERR(main_power_15)) { + pr_err("could not get vana15"); + return PTR_ERR(main_power_15); + } + err = regulator_enable(main_power_15); + if (err) { + pr_err("could not enable vana15\n"); + return err; + } + + /* + * On U300 a special system controller register pulls up the DC + * until the vana15 (LDO D) regulator comes up. At this point, all + * regulators are set and we do not need power control via + * DC ON anymore. This function will likely be moved whenever + * the rest of the U300 power management is implemented. + */ + pr_info("U300: disable system controller pull-up\n"); + val = readw(U300_SYSCON_VBASE + U300_SYSCON_PMCR); + val &= ~U300_SYSCON_PMCR_DCON_ENABLE; + writew(val, U300_SYSCON_VBASE + U300_SYSCON_PMCR); + + /* Register globally exported PM poweroff hook */ + pm_power_off = u300_pm_poweroff; + + return 0; +} + +/* + * So at module init time we hog the regulator! + */ +module_init(u300_init_boardpower); |