From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Date: Mon, 09 May 2022 23:32:16 +0000 Subject: [PATCH v8 08/27] kernel/reboot: Add register_platform_power_off() Message-Id: <20220509233235.995021-9-dmitry.osipenko@collabora.com> List-Id: References: <20220509233235.995021-1-dmitry.osipenko@collabora.com> In-Reply-To: <20220509233235.995021-1-dmitry.osipenko@collabora.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Thierry Reding , Jonathan Hunter , Russell King , Catalin Marinas , Will Deacon , Guo Ren , Geert Uytterhoeven , Greg Ungerer , Joshua Thompson , Thomas Bogendoerfer , Sebastian Reichel , Linus Walleij , Philipp Zabel , Greentime Hu , Vincent Chen , "James E.J. Bottomley" , Helge Deller , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Paul Walmsley , Palmer Dabbelt , Albert Ou , Yoshinori Sato , Rich Felker , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Boris Ostrovsky , Juergen Gross , Stefano Stabellini , "Rafael J. Wysocki" , Len Brown , Santosh Shilimkar , Krzysztof Kozlowski , Liam Girdwood , Mark Brown , Pavel Machek , Lee Jones , Andrew Morton , Guenter Roeck , Daniel Lezcano , Andy Shevchenko , Ulf Hansson , =?UTF-8?q?Micha=C5=82=20Miros=C5=82aw?= Cc: linux-kernel@vger.kernel.org, linux-csky@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-sh@vger.kernel.org, xen-devel@lists.xenproject.org, linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org, linux-tegra@vger.kernel.org Add platform-level registration helpers that will ease transition of the arch/platform power-off callbacks to the new sys-off based API, allowing us to remove the global pm_power_off variable in the future. Signed-off-by: Dmitry Osipenko --- include/linux/reboot.h | 3 +++ kernel/reboot.c | 55 ++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+) diff --git a/include/linux/reboot.h b/include/linux/reboot.h index c52f77ee4ddd..f185b64faae0 100644 --- a/include/linux/reboot.h +++ b/include/linux/reboot.h @@ -141,6 +141,9 @@ int devm_register_sys_off_handler(struct device *dev, int (*callback)(struct sys_off_data *data), void *cb_data); +int register_platform_power_off(void (*power_off)(void)); +void unregister_platform_power_off(void (*power_off)(void)); + /* * Architecture independent implemenations of sys_reboot commands. */ diff --git a/kernel/reboot.c b/kernel/reboot.c index 982e58c11ce8..e74103f2a801 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -469,6 +469,61 @@ int devm_register_sys_off_handler(struct device *dev, } EXPORT_SYMBOL_GPL(devm_register_sys_off_handler); +static struct sys_off_handler *platform_power_off_handler; + +static int platform_power_off_notify(struct sys_off_data *data) +{ + void (*platform_power_power_off_cb)(void) = data->cb_data; + + platform_power_power_off_cb(); + + return NOTIFY_DONE; +} + +/** + * register_platform_power_off - Register platform-level power-off callback + * @power_off: Power-off callback + * + * Registers power-off callback that will be called as last step + * of the power-off sequence. This callback is expected to be invoked + * for the last resort. Only one platform power-off callback is allowed + * to be registered at a time. + * + * Returns zero on success, or error code on failure. + */ +int register_platform_power_off(void (*power_off)(void)) +{ + struct sys_off_handler *handler; + + handler = register_sys_off_handler(SYS_OFF_MODE_POWER_OFF, + SYS_OFF_PRIO_PLATFORM, + platform_power_off_notify, + power_off); + if (IS_ERR(handler)) + return PTR_ERR(handler); + + platform_power_off_handler = handler; + + return 0; +} +EXPORT_SYMBOL_GPL(register_platform_power_off); + +/** + * unregister_platform_power_off - Unregister platform-level power-off callback + * @power_off: Power-off callback + * + * Unregisters previously registered platform power-off callback. + */ +void unregister_platform_power_off(void (*power_off)(void)) +{ + if (platform_power_off_handler && + platform_power_off_handler->cb_data = power_off) { + unregister_sys_off_handler(platform_power_off_handler); + platform_power_off_handler = NULL; + } +} +EXPORT_SYMBOL_GPL(unregister_platform_power_off); + static int legacy_pm_power_off_prepare(struct sys_off_data *data) { if (pm_power_off_prepare) -- 2.35.1