From 1d2bc1067b347a27063cd7b31033c7f93190c2d9 Mon Sep 17 00:00:00 2001
From: Andrey Smirnov <andrew.smirnov@gmail.com>
Date: Sun, 24 Sep 2023 15:02:33 -0700
Subject: [PATCH 09/21] mfd: steamdeck: Expose controller board power in sysfs

As of version 118 Deck's BIOS implements "SCBP" method that allows
gating power of the controller board (VBUS). Add a basic WO method to
our root MFD device to allow toggling that.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
(cherry picked from commit f97f32718acc10cbb51fef925842392e80904d74)
Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
---
 drivers/mfd/steamdeck.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/mfd/steamdeck.c b/drivers/mfd/steamdeck.c
index 0e504b3c2796..a60fa7db9141 100644
--- a/drivers/mfd/steamdeck.c
+++ b/drivers/mfd/steamdeck.c
@@ -41,9 +41,29 @@ struct steamdeck {
 STEAMDECK_ATTR_RO(firmware_version, "PDFW");
 STEAMDECK_ATTR_RO(board_id, "BOID");
 
+static ssize_t controller_board_power_store(struct device *dev,
+					    struct device_attribute *attr,
+					    const char *buf, size_t count)
+{
+	struct steamdeck *sd = dev_get_drvdata(dev);
+	bool enabled;
+	ssize_t ret = kstrtobool(buf, &enabled);
+
+	if (ret)
+		return ret;
+
+	if (ACPI_FAILURE(acpi_execute_simple_method(sd->adev->handle,
+						    "SCBP", enabled)))
+		return -EIO;
+
+	return count;
+}
+static DEVICE_ATTR_WO(controller_board_power);
+
 static struct attribute *steamdeck_attrs[] = {
 	&dev_attr_firmware_version.attr,
 	&dev_attr_board_id.attr,
+	&dev_attr_controller_board_power.attr,
 	NULL
 };
 
-- 
2.45.2

