diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/power/reset/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/power/reset/Makefile | 1 | ||||
| -rw-r--r-- | drivers/power/reset/sc27xx-poweroff.c | 66 |
3 files changed, 76 insertions, 0 deletions
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index 176bd6d..df58fc8 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -225,5 +225,14 @@ config SYSCON_REBOOT_MODE register, then the bootloader can read it to take different action according to the mode. +config POWER_RESET_SC27XX + bool "Spreadtrum SC27xx PMIC power-off driver" + depends on MFD_SC27XX_PMIC || COMPILE_TEST + help + This driver supports powering off a system through + Spreadtrum SC27xx series PMICs. The SC27xx series + PMICs includes the SC2720, SC2721, SC2723, SC2730 + and SC2731 chips. + endif diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index 6b9eb13..7778c74 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -27,3 +27,4 @@ obj-$(CONFIG_POWER_RESET_RMOBILE) += rmobile-reset.o obj-$(CONFIG_POWER_RESET_ZX) += zx-reboot.o obj-$(CONFIG_REBOOT_MODE) += reboot-mode.o obj-$(CONFIG_SYSCON_REBOOT_MODE) += syscon-reboot-mode.o +obj-$(CONFIG_POWER_RESET_SC27XX) += sc27xx-poweroff.o diff --git a/drivers/power/reset/sc27xx-poweroff.c b/drivers/power/reset/sc27xx-poweroff.c new file mode 100644 index 0000000..65c477e --- /dev/null +++ b/drivers/power/reset/sc27xx-poweroff.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Spreadtrum Communications Inc. + * Copyright (C) 2018 Linaro Ltd. + */ + +#include <linux/cpu.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/regmap.h> +#include <linux/syscore_ops.h> + +#define SC27XX_PWR_PD_HW 0xc2c +#define SC27XX_PWR_OFF_EN BIT(0) + +static struct regmap *regmap; + +/* + * On Spreadtrum platform, we need power off system through external SC27xx + * series PMICs, and it is one similar SPI bus mapped by regmap to access PMIC, + * which is not fast io access. + * + * So before stopping other cores, we need release other cores' resource by + * taking cpus down to avoid racing regmap or spi mutex lock when poweroff + * system through PMIC. + */ +void sc27xx_poweroff_shutdown(void) +{ +#ifdef CONFIG_PM_SLEEP_SMP + int cpu = smp_processor_id(); + + freeze_secondary_cpus(cpu); +#endif +} + +static struct syscore_ops poweroff_syscore_ops = { + .shutdown = sc27xx_poweroff_shutdown, +}; + +static void sc27xx_poweroff_do_poweroff(void) +{ + regmap_write(regmap, SC27XX_PWR_PD_HW, SC27XX_PWR_OFF_EN); +} + +static int sc27xx_poweroff_probe(struct platform_device *pdev) +{ + if (regmap) + return -EINVAL; + + regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!regmap) + return -ENODEV; + + pm_power_off = sc27xx_poweroff_do_poweroff; + register_syscore_ops(&poweroff_syscore_ops); + return 0; +} + +static struct platform_driver sc27xx_poweroff_driver = { + .probe = sc27xx_poweroff_probe, + .driver = { + .name = "sc27xx-poweroff", + }, +}; +builtin_platform_driver(sc27xx_poweroff_driver); |
