diff options
Diffstat (limited to 'drivers/input/misc/macsmc-hid.c')
| -rw-r--r-- | drivers/input/misc/macsmc-hid.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/drivers/input/misc/macsmc-hid.c b/drivers/input/misc/macsmc-hid.c new file mode 100644 index 000000000000..c4c7440d4ee6 --- /dev/null +++ b/drivers/input/misc/macsmc-hid.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple SMC input event driver + * Copyright The Asahi Linux Contributors + * + * This driver exposes HID events from the SMC as an input device. + * This includes the lid open/close and power button notifications. + */ + +#include <linux/device.h> +#include <linux/input.h> +#include <linux/mfd/core.h> +#include <linux/mfd/macsmc.h> +#include <linux/reboot.h> + +struct macsmc_hid { + struct device *dev; + struct apple_smc *smc; + struct input_dev *input; + struct notifier_block nb; + bool wakeup_mode; +}; + +#define SMC_EV_BTN 0x7201 +#define SMC_EV_LID 0x7203 + +#define BTN_POWER 0x06 +#define BTN_POWER_HELD1 0xfe +#define BTN_POWER_HELD2 0x00 + +static int macsmc_hid_event(struct notifier_block *nb, unsigned long event, void *data) +{ + struct macsmc_hid *smchid = container_of(nb, struct macsmc_hid, nb); + u16 type = event >> 16; + u8 d1 = (event >> 8) & 0xff; + u8 d2 = event & 0xff; + + switch (type) { + case SMC_EV_BTN: + switch (d1) { + case BTN_POWER: + if (smchid->wakeup_mode) { + if (d2) { + dev_info(smchid->dev, "Button wakeup\n"); + pm_wakeup_hard_event(smchid->dev); + } + } else { + input_report_key(smchid->input, KEY_POWER, d2); + input_sync(smchid->input); + } + break; + case BTN_POWER_HELD1: + /* + * TODO: is this pre-warning useful? + */ + if (d2) + dev_warn(smchid->dev, "Power button held down\n"); + break; + case BTN_POWER_HELD2: + /* + * If we get here, we have about 4 seconds before forced shutdown. + * Try to do an emergency shutdown to make sure the NVMe cache is + * flushed. macOS actually does this by panicing (!)... + */ + if (d2) { + dev_crit(smchid->dev, "Triggering forced shutdown!\n"); + if (kernel_can_power_off()) + kernel_power_off(); + else /* Missing macsmc-reboot driver? */ + kernel_restart("SMC power button triggered restart"); + } + break; + default: + dev_info(smchid->dev, "Unknown SMC button event: %02x %02x\n", d1, d2); + break; + } + return NOTIFY_OK; + case SMC_EV_LID: + if (smchid->wakeup_mode && !d1) { + dev_info(smchid->dev, "Lid wakeup\n"); + pm_wakeup_hard_event(smchid->dev); + } + input_report_switch(smchid->input, SW_LID, d1); + input_sync(smchid->input); + return NOTIFY_OK; + } + + return NOTIFY_DONE; +} + +static int macsmc_hid_probe(struct platform_device *pdev) +{ + struct apple_smc *smc = dev_get_drvdata(pdev->dev.parent); + struct macsmc_hid *smchid; + bool have_lid, have_power; + int ret; + + have_lid = apple_smc_key_exists(smc, SMC_KEY(MSLD)); + have_power = apple_smc_key_exists(smc, SMC_KEY(bHLD)); + + if (!have_lid && !have_power) + return -ENODEV; + + smchid = devm_kzalloc(&pdev->dev, sizeof(*smchid), GFP_KERNEL); + if (!smchid) + return -ENOMEM; + + smchid->dev = &pdev->dev; + smchid->smc = smc; + platform_set_drvdata(pdev, smchid); + + smchid->input = devm_input_allocate_device(&pdev->dev); + if (!smchid->input) + return -ENOMEM; + + smchid->input->phys = "macsmc-hid (0)"; + smchid->input->name = "Apple SMC power/lid events"; + + if (have_lid) + input_set_capability(smchid->input, EV_SW, SW_LID); + if (have_power) + input_set_capability(smchid->input, EV_KEY, KEY_POWER); + + ret = input_register_device(smchid->input); + if (ret) { + dev_err(&pdev->dev, "Failed to register input device: %d\n", ret); + return ret; + } + + if (have_lid) { + u8 val; + + ret = apple_smc_read_u8(smc, SMC_KEY(MSLD), &val); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to read initial lid state\n"); + } else { + input_report_switch(smchid->input, SW_LID, val); + } + } + if (have_power) { + u32 val; + + ret = apple_smc_read_u32(smc, SMC_KEY(bHLD), &val); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to read initial power button state\n"); + } else { + input_report_key(smchid->input, KEY_POWER, val & 1); + } + } + + input_sync(smchid->input); + + smchid->nb.notifier_call = macsmc_hid_event; + apple_smc_register_notifier(smc, &smchid->nb); + + device_init_wakeup(&pdev->dev, 1); + + return 0; +} + +static int macsmc_hid_pm_prepare(struct device *dev) +{ + struct macsmc_hid *smchid = dev_get_drvdata(dev); + + smchid->wakeup_mode = true; + return 0; +} + +static void macsmc_hid_pm_complete(struct device *dev) +{ + struct macsmc_hid *smchid = dev_get_drvdata(dev); + + smchid->wakeup_mode = false; +} + +static const struct dev_pm_ops macsmc_hid_pm_ops = { + .prepare = macsmc_hid_pm_prepare, + .complete = macsmc_hid_pm_complete, +}; + +static struct platform_driver macsmc_hid_driver = { + .driver = { + .name = "macsmc-hid", + .owner = THIS_MODULE, + .pm = &macsmc_hid_pm_ops, + }, + .probe = macsmc_hid_probe, +}; +module_platform_driver(macsmc_hid_driver); + +MODULE_AUTHOR("Hector Martin <marcan@marcan.st>"); +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_DESCRIPTION("Apple SMC GPIO driver"); +MODULE_ALIAS("platform:macsmc-hid"); |