mirror of https://gitee.com/openkylin/linux.git
80 lines
1.9 KiB
C
80 lines
1.9 KiB
C
// 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/module.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)
|
|
#define SC27XX_SLP_CTRL 0xdf0
|
|
#define SC27XX_LDO_XTL_EN BIT(3)
|
|
|
|
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.
|
|
*/
|
|
static void sc27xx_poweroff_shutdown(void)
|
|
{
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
int cpu;
|
|
|
|
for_each_online_cpu(cpu) {
|
|
if (cpu != smp_processor_id())
|
|
remove_cpu(cpu);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
static struct syscore_ops poweroff_syscore_ops = {
|
|
.shutdown = sc27xx_poweroff_shutdown,
|
|
};
|
|
|
|
static void sc27xx_poweroff_do_poweroff(void)
|
|
{
|
|
/* Disable the external subsys connection's power firstly */
|
|
regmap_write(regmap, SC27XX_SLP_CTRL, SC27XX_LDO_XTL_EN);
|
|
|
|
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",
|
|
},
|
|
};
|
|
module_platform_driver(sc27xx_poweroff_driver);
|
|
|
|
MODULE_DESCRIPTION("Power off driver for SC27XX PMIC Device");
|
|
MODULE_AUTHOR("Baolin Wang <baolin.wang@unisoc.com>");
|
|
MODULE_LICENSE("GPL v2");
|