diff options
Diffstat (limited to 'kernel/arch/arm/mach-u300/regulator.c')
-rw-r--r-- | kernel/arch/arm/mach-u300/regulator.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-u300/regulator.c b/kernel/arch/arm/mach-u300/regulator.c new file mode 100644 index 000000000..595b574c2 --- /dev/null +++ b/kernel/arch/arm/mach-u300/regulator.c @@ -0,0 +1,132 @@ +/* + * 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/of.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/regulator/machine.h> +#include <linux/regulator/consumer.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> + +/* Power Management Control 16bit (R/W) */ +#define U300_SYSCON_PMCR (0x50) +#define U300_SYSCON_PMCR_DCON_ENABLE (0x0002) +#define U300_SYSCON_PMCR_PWR_MGNT_ENABLE (0x0001) + +/* + * 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(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct device_node *syscon_np; + struct regmap *regmap; + int err; + + pr_info("U300: setting up board power\n"); + + syscon_np = of_parse_phandle(np, "syscon", 0); + if (!syscon_np) { + pr_crit("U300: no syscon node\n"); + return -ENODEV; + } + regmap = syscon_node_to_regmap(syscon_np); + if (IS_ERR(regmap)) { + pr_crit("U300: could not locate syscon regmap\n"); + return PTR_ERR(regmap); + } + + main_power_15 = regulator_get(&pdev->dev, "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"); + regmap_update_bits(regmap, U300_SYSCON_PMCR, + U300_SYSCON_PMCR_DCON_ENABLE, 0); + + /* Register globally exported PM poweroff hook */ + pm_power_off = u300_pm_poweroff; + + return 0; +} + +static int __init s365_board_probe(struct platform_device *pdev) +{ + return __u300_init_boardpower(pdev); +} + +static const struct of_device_id s365_board_match[] = { + { .compatible = "stericsson,s365" }, + {}, +}; + +static struct platform_driver s365_board_driver = { + .driver = { + .name = "s365-board", + .of_match_table = s365_board_match, + }, +}; + +/* + * So at module init time we hog the regulator! + */ +static int __init u300_init_boardpower(void) +{ + return platform_driver_probe(&s365_board_driver, + s365_board_probe); +} + +device_initcall(u300_init_boardpower); |