Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 235 insertions, 0 deletions

diff --git a/drivers/hwmon/surface_temp.c b/drivers/hwmon/surface_temp.c
new file mode 100644
index 000000000..cd21f331f
--- /dev/null
+++ b/drivers/hwmon/surface_temp.c
@@ -0,0 +1,235 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Thermal sensor subsystem driver for Surface System Aggregator Module (SSAM).
+ *
+ * Copyright (C) 2022-2023 Maximilian Luz <luzmaximilian@gmail.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/hwmon.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+
+#include <linux/surface_aggregator/controller.h>
+#include <linux/surface_aggregator/device.h>
+
+/* -- SAM interface. -------------------------------------------------------- */
+
+/*
+ * Available sensors are indicated by a 16-bit bitfield, where a 1 marks the
+ * presence of a sensor. So we have at most 16 possible sensors/channels.
+ */
+#define SSAM_TMP_SENSOR_MAX_COUNT	16
+
+/*
+ * All names observed so far are 6 characters long, but there's only
+ * zeros after the name, so perhaps they can be longer. This number reflects
+ * the maximum zero-padded space observed in the returned buffer.
+ */
+#define SSAM_TMP_SENSOR_NAME_LENGTH	18
+
+struct ssam_tmp_get_name_rsp {
+	__le16 unknown1;
+	char unknown2;
+	char name[SSAM_TMP_SENSOR_NAME_LENGTH];
+} __packed;
+
+static_assert(sizeof(struct ssam_tmp_get_name_rsp) == 21);
+
+SSAM_DEFINE_SYNC_REQUEST_CL_R(__ssam_tmp_get_available_sensors, __le16, {
+	.target_category = SSAM_SSH_TC_TMP,
+	.command_id      = 0x04,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_MD_R(__ssam_tmp_get_temperature, __le16, {
+	.target_category = SSAM_SSH_TC_TMP,
+	.command_id      = 0x01,
+});
+
+SSAM_DEFINE_SYNC_REQUEST_MD_R(__ssam_tmp_get_name, struct ssam_tmp_get_name_rsp, {
+	.target_category = SSAM_SSH_TC_TMP,
+	.command_id      = 0x0e,
+});
+
+static int ssam_tmp_get_available_sensors(struct ssam_device *sdev, s16 *sensors)
+{
+	__le16 sensors_le;
+	int status;
+
+	status = __ssam_tmp_get_available_sensors(sdev, &sensors_le);
+	if (status)
+		return status;
+
+	*sensors = le16_to_cpu(sensors_le);
+	return 0;
+}
+
+static int ssam_tmp_get_temperature(struct ssam_device *sdev, u8 iid, long *temperature)
+{
+	__le16 temp_le;
+	int status;
+
+	status = __ssam_tmp_get_temperature(sdev->ctrl, sdev->uid.target, iid, &temp_le);
+	if (status)
+		return status;
+
+	/* Convert 1/10 °K to 1/1000 °C */
+	*temperature = (le16_to_cpu(temp_le) - 2731) * 100L;
+	return 0;
+}
+
+static int ssam_tmp_get_name(struct ssam_device *sdev, u8 iid, char *buf, size_t buf_len)
+{
+	struct ssam_tmp_get_name_rsp name_rsp;
+	int status;
+
+	status =  __ssam_tmp_get_name(sdev->ctrl, sdev->uid.target, iid, &name_rsp);
+	if (status)
+		return status;
+
+	/*
+	 * This should not fail unless the name in the returned struct is not
+	 * null-terminated or someone changed something in the struct
+	 * definitions above, since our buffer and struct have the same
+	 * capacity by design. So if this fails, log an error message. Since
+	 * the more likely cause is that the returned string isn't
+	 * null-terminated, we might have received garbage (as opposed to just
+	 * an incomplete string), so also fail the function.
+	 */
+	status = strscpy(buf, name_rsp.name, buf_len);
+	if (status < 0) {
+		dev_err(&sdev->dev, "received non-null-terminated sensor name string\n");
+		return status;
+	}
+
+	return 0;
+}
+
+/* -- Driver.---------------------------------------------------------------- */
+
+struct ssam_temp {
+	struct ssam_device *sdev;
+	s16 sensors;
+	char names[SSAM_TMP_SENSOR_MAX_COUNT][SSAM_TMP_SENSOR_NAME_LENGTH];
+};
+
+static umode_t ssam_temp_hwmon_is_visible(const void *data,
+					  enum hwmon_sensor_types type,
+					  u32 attr, int channel)
+{
+	const struct ssam_temp *ssam_temp = data;
+
+	if (!(ssam_temp->sensors & BIT(channel)))
+		return 0;
+
+	return 0444;
+}
+
+static int ssam_temp_hwmon_read(struct device *dev,
+				enum hwmon_sensor_types type,
+				u32 attr, int channel, long *value)
+{
+	const struct ssam_temp *ssam_temp = dev_get_drvdata(dev);
+
+	return ssam_tmp_get_temperature(ssam_temp->sdev, channel + 1, value);
+}
+
+static int ssam_temp_hwmon_read_string(struct device *dev,
+				       enum hwmon_sensor_types type,
+				       u32 attr, int channel, const char **str)
+{
+	const struct ssam_temp *ssam_temp = dev_get_drvdata(dev);
+
+	*str = ssam_temp->names[channel];
+	return 0;
+}
+
+static const struct hwmon_channel_info * const ssam_temp_hwmon_info[] = {
+	HWMON_CHANNEL_INFO(chip,
+			   HWMON_C_REGISTER_TZ),
+	HWMON_CHANNEL_INFO(temp,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL,
+			   HWMON_T_INPUT | HWMON_T_LABEL),
+	NULL
+};
+
+static const struct hwmon_ops ssam_temp_hwmon_ops = {
+	.is_visible = ssam_temp_hwmon_is_visible,
+	.read = ssam_temp_hwmon_read,
+	.read_string = ssam_temp_hwmon_read_string,
+};
+
+static const struct hwmon_chip_info ssam_temp_hwmon_chip_info = {
+	.ops = &ssam_temp_hwmon_ops,
+	.info = ssam_temp_hwmon_info,
+};
+
+static int ssam_temp_probe(struct ssam_device *sdev)
+{
+	struct ssam_temp *ssam_temp;
+	struct device *hwmon_dev;
+	s16 sensors;
+	int channel;
+	int status;
+
+	status = ssam_tmp_get_available_sensors(sdev, &sensors);
+	if (status)
+		return status;
+
+	ssam_temp = devm_kzalloc(&sdev->dev, sizeof(*ssam_temp), GFP_KERNEL);
+	if (!ssam_temp)
+		return -ENOMEM;
+
+	ssam_temp->sdev = sdev;
+	ssam_temp->sensors = sensors;
+
+	/* Retrieve the name for each available sensor. */
+	for (channel = 0; channel < SSAM_TMP_SENSOR_MAX_COUNT; channel++) {
+		if (!(sensors & BIT(channel)))
+			continue;
+
+		status = ssam_tmp_get_name(sdev, channel + 1, ssam_temp->names[channel],
+					   SSAM_TMP_SENSOR_NAME_LENGTH);
+		if (status)
+			return status;
+	}
+
+	hwmon_dev = devm_hwmon_device_register_with_info(&sdev->dev, "surface_thermal", ssam_temp,
+							 &ssam_temp_hwmon_chip_info, NULL);
+	return PTR_ERR_OR_ZERO(hwmon_dev);
+}
+
+static const struct ssam_device_id ssam_temp_match[] = {
+	{ SSAM_SDEV(TMP, SAM, 0x00, 0x02) },
+	{ },
+};
+MODULE_DEVICE_TABLE(ssam, ssam_temp_match);
+
+static struct ssam_device_driver ssam_temp = {
+	.probe = ssam_temp_probe,
+	.match_table = ssam_temp_match,
+	.driver = {
+		.name = "surface_temp",
+		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
+	},
+};
+module_ssam_device_driver(ssam_temp);
+
+MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>");
+MODULE_DESCRIPTION("Thermal sensor subsystem driver for Surface System Aggregator Module");
+MODULE_LICENSE("GPL");