Hi James,

On Wed, Aug 27, 2025 at 09:22:41PM +1000, James Calligeros wrote:

+static void macsmc_hid_event_button(struct macsmc_hid *smchid, unsigned long event)
+{
+	u8 button = (event >> 8) & 0xff;
+	u8 state = !!(event & 0xff);
+
+	switch (button) {
+	case BTN_POWER:
+	case BTN_TOUCHID:
+		if (smchid->wakeup_mode) {
+			if (state)
+				pm_wakeup_hard_event(smchid->dev);
+		} else {
+			input_report_key(smchid->input, KEY_POWER, state);
+			input_sync(smchid->input);
+		}

I believe you should be using pm_wakeup_event() in all cases so that
pressing power would interrupt suspend even if resume() handler has not
been run yet. Also I do not think suppressing KEY_POWER is needed.
Userspace should be smart and decide whether to shutdown the system or
not when receiving KEY_POWER depending on the overall system state.

...

+
+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;

	int error;

+
+	/* Bail early if this SMC neither supports power button nor lid events */
+	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_warn(&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_warn(&pdev->dev, "Failed to read initial power button state\n");
+		else
+			input_report_key(smchid->input, KEY_POWER, val & 1);
+	}

Since you are doing this to seed initial switch/button state I would do
this before registering input device (this is safe to do so).

Thanks.

-- 
Dmitry