diff options
Diffstat (limited to 'drivers/power/reset')
| -rw-r--r-- | drivers/power/reset/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/power/reset/Makefile | 1 | ||||
| -rw-r--r-- | drivers/power/reset/macsmc-reboot.c | 336 |
3 files changed, 349 insertions, 0 deletions
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index a8c46ba5878f..b4c2b7171672 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -117,6 +117,18 @@ config POWER_RESET_LINKSTATION Say Y here if you have a Buffalo LinkStation LS421D/E. +config POWER_RESET_MACSMC + tristate "Apple SMC reset/power-off driver" + depends on ARCH_APPLE || COMPILE_TEST + depends on APPLE_SMC + depends on OF + default ARCH_APPLE + help + This driver supports reset and power-off on Apple Mac machines + that implement this functionality via the SMC. + + Say Y here if you have an Apple Silicon Mac. + config POWER_RESET_MSM bool "Qualcomm MSM power-off driver" depends on ARCH_QCOM diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index 0a39424fc558..5838768e106f 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o obj-$(CONFIG_POWER_RESET_GPIO_RESTART) += gpio-restart.o obj-$(CONFIG_POWER_RESET_HISI) += hisi-reboot.o obj-$(CONFIG_POWER_RESET_LINKSTATION) += linkstation-poweroff.o +obj-$(CONFIG_POWER_RESET_MACSMC) += macsmc-reboot.o obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o obj-$(CONFIG_POWER_RESET_MT6323) += mt6323-poweroff.o obj-$(CONFIG_POWER_RESET_OXNAS) += oxnas-restart.o diff --git a/drivers/power/reset/macsmc-reboot.c b/drivers/power/reset/macsmc-reboot.c new file mode 100644 index 000000000000..c33ba2a7852d --- /dev/null +++ b/drivers/power/reset/macsmc-reboot.c @@ -0,0 +1,336 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple SMC Reboot/Poweroff Handler + * Copyright The Asahi Linux Contributors + */ + +#include <linux/delay.h> +#include <linux/mfd/core.h> +#include <linux/mfd/macsmc.h> +#include <linux/module.h> +#include <linux/nvmem-consumer.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> +#include <linux/slab.h> + +struct macsmc_reboot_nvmem { + struct nvmem_cell *shutdown_flag; + struct nvmem_cell *pm_setting; + struct nvmem_cell *boot_stage; + struct nvmem_cell *boot_error_count; + struct nvmem_cell *panic_count; +}; + +static const char *nvmem_names[] = { + "shutdown_flag", + "pm_setting", + "boot_stage", + "boot_error_count", + "panic_count", +}; + +enum boot_stage { + BOOT_STAGE_SHUTDOWN = 0x00, /* Clean shutdown */ + BOOT_STAGE_IBOOT_DONE = 0x2f, /* Last stage of bootloader */ + BOOT_STAGE_KERNEL_STARTED = 0x30, /* Normal OS booting */ +}; + +enum pm_setting { + PM_SETTING_AC_POWER_RESTORE = 0x02, + PM_SETTING_AC_POWER_OFF = 0x03, +}; + +static const char *ac_power_modes[] = { "off", "restore" }; + +static int ac_power_mode_map[] = { + PM_SETTING_AC_POWER_OFF, + PM_SETTING_AC_POWER_RESTORE, +}; + +struct macsmc_reboot { + struct device *dev; + struct apple_smc *smc; + struct notifier_block reboot_notify; + + union { + struct macsmc_reboot_nvmem nvm; + struct nvmem_cell *nvm_cells[ARRAY_SIZE(nvmem_names)]; + }; +}; + +/* Helpers to read/write a u8 given a struct nvmem_cell */ +static int nvmem_cell_get_u8(struct nvmem_cell *cell) +{ + size_t len; + u8 val; + void *ret = nvmem_cell_read(cell, &len); + + if (IS_ERR(ret)) + return PTR_ERR(ret); + + if (len < 1) { + kfree(ret); + return -EINVAL; + } + + val = *(u8 *)ret; + kfree(ret); + return val; +} + +static int nvmem_cell_set_u8(struct nvmem_cell *cell, u8 val) +{ + return nvmem_cell_write(cell, &val, sizeof(val)); +} + +static ssize_t macsmc_ac_power_mode_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t n) +{ + struct macsmc_reboot *reboot = dev_get_drvdata(dev); + int mode; + int ret; + + mode = sysfs_match_string(ac_power_modes, buf); + if (mode < 0) + return mode; + + ret = nvmem_cell_set_u8(reboot->nvm.pm_setting, ac_power_mode_map[mode]); + if (ret < 0) + return ret; + + return n; +} + +static ssize_t macsmc_ac_power_mode_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct macsmc_reboot *reboot = dev_get_drvdata(dev); + int len = 0; + int i; + int mode = nvmem_cell_get_u8(reboot->nvm.pm_setting); + + if (mode < 0) + return mode; + + for (i = 0; i < ARRAY_SIZE(ac_power_mode_map); i++) + if (mode == ac_power_mode_map[i]) + len += scnprintf(buf+len, PAGE_SIZE-len, + "[%s] ", ac_power_modes[i]); + else + len += scnprintf(buf+len, PAGE_SIZE-len, + "%s ", ac_power_modes[i]); + buf[len-1] = '\n'; + return len; +} +static DEVICE_ATTR(ac_power_mode, 0644, macsmc_ac_power_mode_show, + macsmc_ac_power_mode_store); + +/* + * SMC 'MBSE' key actions: + * + * 'offw' - shutdown warning + * 'slpw' - sleep warning + * 'rest' - restart warning + * 'off1' - shutdown (needs PMU bit set to stay on) + * 'susp' - suspend + * 'phra' - restart ("PE Halt Restart Action"?) + * 'panb' - panic beginning + * 'pane' - panic end + */ + +static int macsmc_power_off(struct sys_off_data *data) +{ + struct macsmc_reboot *reboot = data->cb_data; + + dev_info(reboot->dev, "Issuing power off (off1)\n"); + + if (apple_smc_write_u32_atomic(reboot->smc, SMC_KEY(MBSE), SMC_KEY(off1)) < 0) { + dev_err(reboot->dev, "Failed to issue MBSE = off1 (power_off)\n"); + } else { + mdelay(100); + WARN_ON(1); + } + + return NOTIFY_OK; +} + +static int macsmc_restart(struct sys_off_data *data) +{ + struct macsmc_reboot *reboot = data->cb_data; + + dev_info(reboot->dev, "Issuing restart (phra)\n"); + + if (apple_smc_write_u32_atomic(reboot->smc, SMC_KEY(MBSE), SMC_KEY(phra)) < 0) { + dev_err(reboot->dev, "Failed to issue MBSE = phra (restart)\n"); + } else { + mdelay(100); + WARN_ON(1); + } + + return NOTIFY_OK; +} + +static int macsmc_reboot_notify(struct notifier_block *this, unsigned long action, void *data) +{ + struct macsmc_reboot *reboot = container_of(this, struct macsmc_reboot, reboot_notify); + u32 val; + u8 shutdown_flag; + + switch (action) { + case SYS_RESTART: + val = SMC_KEY(rest); + shutdown_flag = 0; + break; + case SYS_POWER_OFF: + val = SMC_KEY(offw); + shutdown_flag = 1; + break; + default: + return NOTIFY_DONE; + } + + dev_info(reboot->dev, "Preparing for reboot (%p4ch)\n", &val); + + /* On the Mac Mini, this will turn off the LED for power off */ + if (apple_smc_write_u32(reboot->smc, SMC_KEY(MBSE), val) < 0) + dev_err(reboot->dev, "Failed to issue MBSE = %p4ch (reboot_prepare)\n", &val); + + /* Set the boot_stage to 0, which means we're doing a clean shutdown/reboot. */ + if (reboot->nvm.boot_stage && + nvmem_cell_set_u8(reboot->nvm.boot_stage, BOOT_STAGE_SHUTDOWN) < 0) + dev_err(reboot->dev, "Failed to write boot_stage\n"); + + /* + * Set the PMU flag to actually reboot into the off state. + * Without this, the device will just reboot. We make it optional in case it is no longer + * necessary on newer hardware. + */ + if (reboot->nvm.shutdown_flag && + nvmem_cell_set_u8(reboot->nvm.shutdown_flag, shutdown_flag) < 0) + dev_err(reboot->dev, "Failed to write shutdown_flag\n"); + + return NOTIFY_OK; +} + +static void macsmc_power_init_error_counts(struct macsmc_reboot *reboot) +{ + int boot_error_count, panic_count; + + if (!reboot->nvm.boot_error_count || !reboot->nvm.panic_count) + return; + + boot_error_count = nvmem_cell_get_u8(reboot->nvm.boot_error_count); + if (boot_error_count < 0) { + dev_err(reboot->dev, "Failed to read boot_error_count (%d)\n", boot_error_count); + return; + } + + panic_count = nvmem_cell_get_u8(reboot->nvm.panic_count); + if (panic_count < 0) { + dev_err(reboot->dev, "Failed to read panic_count (%d)\n", panic_count); + return; + } + + if (!boot_error_count && !panic_count) + return; + + dev_warn(reboot->dev, "PMU logged %d boot error(s) and %d panic(s)\n", + boot_error_count, panic_count); + + if (nvmem_cell_set_u8(reboot->nvm.panic_count, 0) < 0) + dev_err(reboot->dev, "Failed to reset panic_count\n"); + if (nvmem_cell_set_u8(reboot->nvm.boot_error_count, 0) < 0) + dev_err(reboot->dev, "Failed to reset boot_error_count\n"); +} + +static int macsmc_reboot_probe(struct platform_device *pdev) +{ + struct apple_smc *smc = dev_get_drvdata(pdev->dev.parent); + struct macsmc_reboot *reboot; + int ret, i; + + /* Ignore devices without this functionality */ + if (!apple_smc_key_exists(smc, SMC_KEY(MBSE))) + return -ENODEV; + + reboot = devm_kzalloc(&pdev->dev, sizeof(*reboot), GFP_KERNEL); + if (!reboot) + return -ENOMEM; + + reboot->dev = &pdev->dev; + reboot->smc = smc; + + platform_set_drvdata(pdev, reboot); + + pdev->dev.of_node = of_get_child_by_name(pdev->dev.parent->of_node, "reboot"); + + for (i = 0; i < ARRAY_SIZE(nvmem_names); i++) { + struct nvmem_cell *cell; + cell = devm_nvmem_cell_get(&pdev->dev, + nvmem_names[i]); + if (IS_ERR(cell)) { + if (PTR_ERR(cell) == -EPROBE_DEFER) + return -EPROBE_DEFER; + dev_warn(&pdev->dev, "Missing NVMEM cell %s (%ld)\n", + nvmem_names[i], PTR_ERR(cell)); + /* Non fatal, we'll deal with it */ + cell = NULL; + } + reboot->nvm_cells[i] = cell; + } + + /* Set the boot_stage to indicate we're running the OS kernel */ + if (reboot->nvm.boot_stage && + nvmem_cell_set_u8(reboot->nvm.boot_stage, BOOT_STAGE_KERNEL_STARTED) < 0) + dev_err(reboot->dev, "Failed to write boot_stage\n"); + + /* Display and clear the error counts */ + macsmc_power_init_error_counts(reboot); + + reboot->reboot_notify.notifier_call = macsmc_reboot_notify; + + ret = devm_register_sys_off_handler(&pdev->dev, SYS_OFF_MODE_POWER_OFF, SYS_OFF_PRIO_HIGH, + macsmc_power_off, reboot); + if (ret) + return dev_err_probe(&pdev->dev, ret, "Failed to register power-off handler\n"); + + ret = devm_register_sys_off_handler(&pdev->dev, SYS_OFF_MODE_RESTART, SYS_OFF_PRIO_HIGH, + macsmc_restart, reboot); + if (ret) + return dev_err_probe(&pdev->dev, ret, "Failed to register restart handler\n"); + + ret = devm_register_reboot_notifier(&pdev->dev, &reboot->reboot_notify); + if (ret) + return dev_err_probe(&pdev->dev, ret, "Failed to register reboot notifier\n"); + + dev_info(&pdev->dev, "Handling reboot and poweroff requests via SMC\n"); + + if (device_create_file(&pdev->dev, &dev_attr_ac_power_mode)) + dev_warn(&pdev->dev, "could not create sysfs file\n"); + + return 0; +} + +static int macsmc_reboot_remove(struct platform_device *pdev) +{ + device_remove_file(&pdev->dev, &dev_attr_ac_power_mode); + + return 0; +} + + +static struct platform_driver macsmc_reboot_driver = { + .driver = { + .name = "macsmc-reboot", + .owner = THIS_MODULE, + }, + .probe = macsmc_reboot_probe, + .remove = macsmc_reboot_remove, +}; +module_platform_driver(macsmc_reboot_driver); + +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_DESCRIPTION("Apple SMC reboot/poweroff driver"); +MODULE_AUTHOR("Hector Martin <marcan@marcan.st>"); +MODULE_ALIAS("platform:macsmc-reboot"); |