Messages in this thread | | | Date | Thu, 8 Feb 2018 22:50:12 +0100 | From | Sebastian Reichel <> | Subject | Re: [PATCH] power: reset: Add Spreadtrum SC27xx PMIC power off support |
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Hi Baolin,
On Mon, Jan 15, 2018 at 03:58:57PM +0800, Baolin Wang wrote: > On Spreadtrum platform, we need power off system through external SC27xx > series PMICs including the SC2720, SC2721, SC2723, SC2730 and SC2731 chips. > Thus this patch adds SC27xx series PMICs power-off support. > > Signed-off-by: Baolin Wang <baolin.wang@linaro.org> > --- > drivers/power/reset/Kconfig | 9 +++++ > drivers/power/reset/Makefile | 1 + > drivers/power/reset/sc27xx-poweroff.c | 65 +++++++++++++++++++++++++++++++++ > 3 files changed, 75 insertions(+) > create mode 100644 drivers/power/reset/sc27xx-poweroff.c > > diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig > index ca0de1a..611ae56 100644 > --- a/drivers/power/reset/Kconfig > +++ b/drivers/power/reset/Kconfig > @@ -227,5 +227,14 @@ config SYSCON_REBOOT_MODE > register, then the bootloader can read it to take different > action according to the mode. > > +config POWER_RESET_SC27XX > + tristate "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 aeb65ed..225d645 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..8e4b6a0 > --- /dev/null > +++ b/drivers/power/reset/sc27xx-poweroff.c > @@ -0,0 +1,65 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Copyright (C) 2017 Spreadtrum Communications Inc. > + * Copyright (c) 2017 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) > + > +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) > +{ > + int cpu = smp_processor_id(); > + > + freeze_secondary_cpus(cpu); > +} > + > +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 void sc27xx_poweroff_remove(struct platform_device *pdev) { if (pm_power_off == sc27xx_poweroff_do_poweroff) pm_power_off = NULL; regmap = NULL; }
> +static struct platform_driver sc27xx_poweroff_driver = { > + .probe = sc27xx_poweroff_probe,
.remove = sc27xx_poweroff_remove,
> + .driver = { > + .name = "sc27xx-poweroff", > + }, > +}; > +module_platform_driver(sc27xx_poweroff_driver); > + > +MODULE_DESCRIPTION("Spreadtrum SC27xx PMIC Poweroff Driver"); > +MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:sc27xx-poweroff");
Otherwise looks fine.
-- Sebastian [unhandled content-type:application/pgp-signature] | |