[PATCH v4 14/20] ACPI: platform_profile: Only show profiles common for all handlers

[Mario Limonciello <mario.limonciello@amd.com>]

If multiple platform profile handlers have been registered, don't allow
switching to profiles unique to only one handler.

Tested-by: Matthew Schwartz <matthew.schwartz@linux.dev>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
---
 drivers/acpi/platform_profile.c | 55 +++++++++++++++++++++++----------
 1 file changed, 38 insertions(+), 17 deletions(-)

diff --git a/drivers/acpi/platform_profile.c b/drivers/acpi/platform_profile.c
index c9917daf683cb..8de7c8352673e 100644
--- a/drivers/acpi/platform_profile.c
+++ b/drivers/acpi/platform_profile.c
@@ -235,27 +235,48 @@ static const struct class platform_profile_class = {
 	.dev_groups = profile_groups,
 };
 
-static ssize_t platform_profile_choices_show(struct device *dev,
-					struct device_attribute *attr,
-					char *buf)
+/**
+ * _aggregate_choices - Aggregate the available profile choices
+ * @dev: The device
+ * @data: The available profile choices
+ * Return: 0 on success, -errno on failure
+ */
+static int _aggregate_choices(struct device *dev, void *data)
 {
-	int len = 0;
-	int i;
+	unsigned long *aggregate = data;
+	unsigned long choices = 0;
+	int err;
 
-	scoped_cond_guard(mutex_intr, return -ERESTARTSYS, &profile_lock) {
-		if (!cur_profile)
-			return -ENODEV;
+	err = _get_class_choices(dev, &choices);
+	if (err)
+		return err;
 
-		for_each_set_bit(i, cur_profile->choices, PLATFORM_PROFILE_LAST) {
-			if (len == 0)
-				len += sysfs_emit_at(buf, len, "%s", profile_names[i]);
-			else
-				len += sysfs_emit_at(buf, len, " %s", profile_names[i]);
-		}
-	}
-	len += sysfs_emit_at(buf, len, "\n");
+	if (!*aggregate)
+		*aggregate = choices;
+	else
+		*aggregate &= choices;
 
-	return len;
+	return 0;
+}
+
+/**
+ * platform_profile_choices_show - Show the available profile choices for legacy sysfs interface
+ * @dev: The device
+ * @attr: The attribute
+ * @buf: The buffer to write to
+ * Return: The number of bytes written
+ */
+static ssize_t platform_profile_choices_show(struct device *dev,
+					     struct device_attribute *attr,
+					     char *buf)
+{
+	unsigned long aggregate = 0;
+	int err;
+
+	err = class_for_each_device(&platform_profile_class, NULL,
+				    &aggregate, _aggregate_choices);
+
+	return _commmon_choices_show(aggregate, buf);
 }
 
 static ssize_t platform_profile_show(struct device *dev,
-- 
2.43.0