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path: root/drivers/input/misc/macsmc-hid.c
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Diffstat (limited to 'drivers/input/misc/macsmc-hid.c')
-rw-r--r--drivers/input/misc/macsmc-hid.c196
1 files changed, 196 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..49296cbb70cc
--- /dev/null
+++ b/drivers/input/misc/macsmc-hid.c
@@ -0,0 +1,196 @@
+// 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 0x01
+#define BTN_TOUCHID 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:
+ case BTN_TOUCHID:
+ 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");