mfd: macsmc: T6050 power, reboot, RTC and sensors, and ac_power_mode

Documentation/ABI/testing/sysfs-driver-macsmc-reboot

@@ -0,0 +1,16 @@
+What:		/sys/bus/platform/drivers/macsmc-reboot/<dev>/ac_power_mode
+Date:		November 2026
+KernelVersion:	7.4
+Description:
+		What the machine does when external power arrives, as kept in
+		the PMU (present only when the device tree gives the reboot
+		node a pm_setting cell). Reading lists the modes with the
+		current one in brackets; writing a mode name sets it:
+
+		off:
+			stay off
+		restore:
+			power on after a power loss if the machine was on
+		always:
+			power on whenever power is connected (the 2024 and later
+			desktops; other machines may ignore it)

Documentation/devicetree/bindings/hwmon/apple,smc-hwmon.yaml

@@ -62,7 +62,9 @@ properties:
       follow the temperature-* children in the listed order and are labelled
       "SoC die <key>". Keys absent from the running firmware or with an
       unsupported format are skipped. These channels do not change the indices
-      used by thermal-sensors references to temperature-* children.
+      used by thermal-sensors references to temperature-* children. With
+      apple,discover-temperatures, a listed key adds no channel; its
+      discovered channel (labelled with the key) supplies the zone.
 
   apple,thermal-pressure-key:
     $ref: /schemas/types.yaml#/definitions/string

Documentation/devicetree/bindings/mfd/apple,smc.yaml

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) AND GPL-2.0-only
 %YAML 1.2
 ---
 $id: http://devicetree.org/schemas/mfd/apple,smc.yaml#

Documentation/hwmon/macsmc-hwmon.rst

@@ -43,6 +43,8 @@ Only readable four-byte floating-point keys are used. When thermal support is
 enabled, their hottest reading supplies the ``macsmc_soc_die`` thermal zone.
 A failed or implausible reading fails the zone read rather than reporting a
 partial result. Keys absent from the firmware are skipped.
+With ``apple,discover-temperatures`` the listed keys add no channels: the
+discovered channel of each listed key, labelled with the key, joins the zone.
 
 The optional ``apple,thermal-pressure-key`` on the same node describes a
 readable signed 32-bit firmware thermal pressure level. Neither feature needs

drivers/gpio/gpio-macsmc.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0-only OR MIT
+// SPDX-License-Identifier: (GPL-2.0-only OR MIT) AND GPL-2.0-only
 /*
  * Apple SMC GPIO driver
  * Copyright The Asahi Linux Contributors
@@ -16,6 +16,7 @@
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/soc/apple/t8132.h>
+#include <linux/unaligned.h>
 
 #define MAX_GPIO 64
 
@@ -103,6 +104,7 @@ struct macsmc_gpio {
 	struct apple_smc *smc;
 	struct gpio_chip gc;
 
+	u64 *output_commands;
 	int first_index;
 	smc_key base_key;
 
@@ -383,6 +385,76 @@ static int macsmc_gpio_init_valid_mask(struct gpio_chip *gc,
 	return 0;
 }
 
+/* Each DT template identifies one output; its low 16 bits carry the value. */
+static int macsmc_pcio_set(struct gpio_chip *gc, unsigned int offset, int value)
+{
+	struct macsmc_gpio *smcgp = gpiochip_get_data(gc);
+	u8 command[8];
+	int ret;
+
+	put_unaligned_le64(smcgp->output_commands[offset] | !!value, command);
+	ret = apple_smc_write(smcgp->smc, SMC_KEY(pcIO), command, sizeof(command));
+	/* SMC writes return status, not a byte count. */
+	return ret < 0 ? ret : 0;
+}
+
+static int macsmc_pcio_get(struct gpio_chip *gc, unsigned int offset)
+{
+	/* The native output command has no established input/readback operation. */
+	return -EOPNOTSUPP;
+}
+
+static int macsmc_pcio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+	return GPIO_LINE_DIRECTION_OUT;
+}
+
+static int macsmc_pcio_probe(struct macsmc_gpio *smcgp)
+{
+	struct device *dev = smcgp->dev;
+	struct apple_smc_key_info info;
+	int count, ret;
+
+	/* A board that uses none of the outputs leaves the list out. */
+	if (!of_property_present(dev->of_node, "apple,output-commands"))
+		return -ENODEV;
+
+	ret = apple_smc_get_key_info(smcgp->smc, SMC_KEY(pcIO), &info);
+	if (ret < 0)
+		return ret;
+	if (info.size != 8 || !(info.flags & APPLE_SMC_WRITABLE))
+		return dev_err_probe(dev, -EINVAL, "pcIO is not an eight-byte output key\n");
+	count = of_property_count_u64_elems(dev->of_node, "apple,output-commands");
+	if (count <= 0 || count > MAX_GPIO)
+		return -EINVAL;
+	smcgp->output_commands = devm_kcalloc(dev, count, sizeof(u64), GFP_KERNEL);
+	if (!smcgp->output_commands)
+		return -ENOMEM;
+	ret = of_property_read_u64_array(dev->of_node, "apple,output-commands",
+					smcgp->output_commands, count);
+	if (ret)
+		return ret;
+	for (int i = 0; i < count; i++) {
+		if (smcgp->output_commands[i] & 0xffff)
+			return -EINVAL;
+		for (int j = 0; j < i; j++)
+			if (smcgp->output_commands[i] == smcgp->output_commands[j])
+				return -EINVAL;
+	}
+
+	smcgp->gc.label = "macsmc-pcio-output";
+	smcgp->gc.owner = THIS_MODULE;
+	smcgp->gc.get = macsmc_pcio_get;
+	smcgp->gc.set = macsmc_pcio_set;
+	smcgp->gc.direction_output = macsmc_pcio_set;
+	smcgp->gc.get_direction = macsmc_pcio_get_direction;
+	smcgp->gc.can_sleep = true;
+	smcgp->gc.ngpio = count;
+	smcgp->gc.base = -1;
+	smcgp->gc.parent = dev;
+	return devm_gpiochip_add_data(dev, &smcgp->gc, smcgp);
+}
+
 struct macsmc_gpio_of_match_data {
 	smc_key base_key;
 };
@@ -449,6 +521,8 @@ static int macsmc_gpio_probe(struct platform_device *pdev)
 
 	smcgp->dev = &pdev->dev;
 	smcgp->smc = smc;
+	if (device_is_compatible(&pdev->dev, "apple,smc-pcio-gpio"))
+		return macsmc_pcio_probe(smcgp);
 	smcgp->base_key = data ? data->base_key : _SMC_KEY("gP\0\0");
 	smcgp->j700_pcio = of_machine_is_compatible("apple,j700") &&
 				device_is_compatible(&pdev->dev, "apple,smc-gpio");
@@ -498,6 +572,7 @@ static const struct macsmc_gpio_of_match_data macsmc_gpio_low_data = {
 };
 
 static const struct of_device_id macsmc_gpio_of_table[] = {
+	{ .compatible = "apple,smc-pcio-gpio" },
 	{
 		.compatible = "apple,smc-gpio",
 		.data = &macsmc_gpio_up_data,

drivers/hwmon/macsmc-hwmon.c

@@ -901,6 +901,9 @@ static int macsmc_hwmon_discover_temperatures(struct macsmc_hwmon *hwmon)
 	if (!smc->key_count || smc->key_count > U16_MAX)
 		return -EINVAL;
 
+	ret = of_property_count_strings(hwmon->dev->of_node, "apple,soc-die-keys");
+	hwmon->die_listed = ret > 0 ? ret : 0;
+
 	hwmon->temp.sensors = devm_kcalloc(hwmon->dev, smc->key_count,
 					   sizeof(*sensor), GFP_KERNEL);
 	if (!hwmon->temp.sensors)
@@ -934,6 +937,12 @@ static int macsmc_hwmon_discover_temperatures(struct macsmc_hwmon *hwmon)
 		/* Key identity only: do not invent locations or calibration. */
 		snprintf(sensor->label, sizeof(sensor->label), "%c%c%c%c",
 			 key >> 24, (key >> 16) & 0xff, (key >> 8) & 0xff, key & 0xff);
+		/* A listed SoC die key keeps its discovered channel and joins the die zone. */
+		if (of_property_match_string(hwmon->dev->of_node, "apple,soc-die-keys",
+					     sensor->label) >= 0) {
+			sensor->die = true;
+			hwmon->die_count++;
+		}
 	}
 
 	return 0;
@@ -1117,7 +1126,11 @@ static int macsmc_hwmon_populate_sensors(struct macsmc_hwmon *hwmon,
 	for_each_child_of_node_with_prefix(hwmon_node, key_node, "temperature-") {
 		n_temperature++;
 	}
-	n_temperature += n_die_keys;
+	/* With discovery, listed die keys mark discovered channels instead (see there). */
+	if (!of_property_read_bool(hwmon_node, "apple,discover-temperatures"))
+		n_temperature += n_die_keys;
+	else
+		n_die_keys = 0;
 
 	if (n_temperature) {
 		hwmon->temp.sensors = devm_kcalloc(hwmon->dev, n_temperature,

drivers/mfd/macsmc.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0-only OR MIT
+// SPDX-License-Identifier: (GPL-2.0-only OR MIT) AND GPL-2.0-only
 /*
  * Apple SMC (System Management Controller) MFD driver
  *
@@ -59,9 +59,54 @@ static const struct mfd_cell apple_smc_devs[] = {
 	MFD_CELL_OF("macsmc-rtc", NULL, NULL, 0, 0, "apple,smc-rtc"),
 };
 
-/* The second GPIO bank ('gp' keys) only exists on some SMCs. */
-static const struct mfd_cell apple_smc_low_gpio_dev =
-	MFD_CELL_OF("macsmc-low-gpio", NULL, NULL, 0, 0, "apple,smc-low-gpio");
+/* This profile exposes notifications and the explicitly described outputs. */
+static const struct mfd_cell apple_smc_t6050_devs[] = {
+	MFD_CELL_NAME("macsmc-input"),
+	MFD_CELL_NAME("macsmc-power"),
+	MFD_CELL_OF("macsmc-hwmon", NULL, NULL, 0, 0, "apple,smc-hwmon"),
+};
+
+/*
+ * Cells registered only where the device tree describes them: the MFD core would otherwise
+ * create an unbound device and warn that it found no node on every SMC without one. The pcIO
+ * outputs and the second GPIO bank ('gp' keys) only exist on some SMCs.
+ */
+static const struct mfd_cell apple_smc_described_devs[] = {
+	MFD_CELL_OF("macsmc-gpio", NULL, NULL, 0, 0, "apple,smc-pcio-gpio"),
+	MFD_CELL_OF("macsmc-low-gpio", NULL, NULL, 0, 0, "apple,smc-low-gpio"),
+};
+
+/*
+ * T6050's reboot/power-off and RTC, for a kernel that owns the machine (J775D, booted bare
+ * metal). Registered only where the device tree describes them, so a T6050 device tree without
+ * them registers what it did before.
+ */
+static const struct mfd_cell apple_smc_t6050_described_devs[] = {
+	MFD_CELL_OF("macsmc-reboot", NULL, NULL, 0, 0, "apple,smc-reboot"),
+	MFD_CELL_OF("macsmc-rtc", NULL, NULL, 0, 0, "apple,smc-rtc"),
+};
+
+static int apple_smc_add_described_devices(struct apple_smc *smc, const struct mfd_cell *cells,
+					   size_t count)
+{
+	struct device_node *np;
+	size_t i;
+	int ret;
+
+	for (i = 0; i < count; i++) {
+		np = of_get_compatible_child(smc->dev->of_node, cells[i].of_compatible);
+		if (!np)
+			continue;
+		of_node_put(np);
+		ret = devm_mfd_add_devices(smc->dev, PLATFORM_DEVID_NONE, &cells[i], 1,
+					   NULL, 0, NULL);
+		if (ret)
+			return dev_err_probe(smc->dev, ret, "Failed to register %s\n",
+					     cells[i].name);
+	}
+
+	return 0;
+}
 
 /* T8152 currently exposes read-only telemetry; firmware owns fan control. */
 static const struct mfd_cell apple_smc_telemetry_devs[] = {
@@ -250,8 +295,8 @@ int apple_smc_get_key_info(struct apple_smc *smc, smc_key key, struct apple_smc_
 	u8 key_info[6];
 	int ret;
 
+	/* Keep the shared reply buffer stable until its metadata is copied. */
 	guard(mutex)(&smc->mutex);
-
 	ret = apple_smc_cmd_locked(smc, SMC_MSG_GET_KEY_INFO, key, 0, 0, NULL);
 	if (ret >= 0 && info) {
 		apple_smc_read_sram(smc, key_info, sizeof(key_info));
@@ -483,9 +528,9 @@ static void apple_smc_disable_notifications(void *data)
 static int apple_smc_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	struct device_node *np;
 	struct apple_smc *smc;
 	__be32 count = 0;
+	bool t6050;
 	int ret;
 
 	smc = devm_kzalloc(dev, sizeof(*smc), GFP_KERNEL);
@@ -559,32 +604,30 @@ static int apple_smc_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	ret = devm_mfd_add_devices(smc->dev, PLATFORM_DEVID_NONE,
-				   apple_smc_devs, ARRAY_SIZE(apple_smc_devs),
-				   NULL, 0, NULL);
+	t6050 = of_device_is_compatible(dev->of_node, "apple,t6050-smc");
+	if (t6050)
+		ret = devm_mfd_add_devices(smc->dev, PLATFORM_DEVID_NONE,
+					 apple_smc_t6050_devs,
+					 ARRAY_SIZE(apple_smc_t6050_devs), NULL, 0, NULL);
+	else
+		ret = devm_mfd_add_devices(smc->dev, PLATFORM_DEVID_NONE,
+					 apple_smc_devs, ARRAY_SIZE(apple_smc_devs),
+					 NULL, 0, NULL);
 	if (ret)
 		return dev_err_probe(smc->dev, ret, "Failed to register sub-devices");
 
-	/*
-	 * Register the second GPIO bank only where the device tree describes
-	 * it: the MFD core would otherwise create an unbound device and warn
-	 * that it found no node on every SMC without one.
-	 */
-	np = of_get_compatible_child(dev->of_node, "apple,smc-low-gpio");
-	if (np) {
-		of_node_put(np);
-		ret = devm_mfd_add_devices(smc->dev, PLATFORM_DEVID_NONE,
-					   &apple_smc_low_gpio_dev, 1, NULL, 0, NULL);
-		if (ret)
-			return dev_err_probe(smc->dev, ret,
-					     "Failed to register the second GPIO bank");
-	}
+	ret = apple_smc_add_described_devices(smc, apple_smc_described_devs,
+					      ARRAY_SIZE(apple_smc_described_devs));
+	if (ret || !t6050)
+		return ret;
 
-	return 0;
+	return apple_smc_add_described_devices(smc, apple_smc_t6050_described_devs,
+					       ARRAY_SIZE(apple_smc_t6050_described_devs));
 }
 
 static const struct of_device_id apple_smc_of_match[] = {
 	{ .compatible = "apple,t8152-smc" },
+	{ .compatible = "apple,t6050-smc" },
 	{ .compatible = "apple,t8103-smc" },
 	{ .compatible = "apple,smc" },
 	{},