linux-t2-patches/3006-chamshell.patch

From 09ad52ccc7c32ab24f0a7b254fb8707a849b2f80 Mon Sep 17 00:00:00 2001
From: Atharva Tiwari <atharvatiwarilinuxdev@gmail.com>
Date: Fri, 24 Apr 2026 19:18:48 +0530
Subject: [PATCH 06/12] chamshell

Signed-off-by: Atharva Tiwari <atharvatiwarilinuxdev@gmail.com>
---
 MAINTAINERS                           |  1 +
 drivers/input/misc/Kconfig            | 12 ++++
 drivers/input/misc/Makefile           |  1 +
 drivers/input/misc/macsmc-chamshell.c | 97 +++++++++++++++++++++++++++
 drivers/mfd/macsmc-core.c             |  1 +
 5 files changed, 112 insertions(+)
 create mode 100644 drivers/input/misc/macsmc-chamshell.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 2f9573d6e6b7..c7adaab97960 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1942,6 +1942,7 @@ M:	Atharva Tiwari <atharvatiwarilinuxdev@gmail.com>
 S:	Odd fixes
 F:	drivers/iio/accel/macsmc-accel.c
 F:	drivers/iio/light/macsmc-light.c
+F:	drivers/input/misc/macsmc-chamshell.c
 F:	drivers/leds/leds-macsmc.c
 F:	drivers/platform/x86/macsmc-acpi.c
 
diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 94a753fcb64f..dc624a421704 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -248,6 +248,18 @@ config INPUT_SPARCSPKR
 	  To compile this driver as a module, choose M here: the
 	  module will be called sparcspkr.
 
+config INPUT_MACSMC_CHAMSHELL
+	tristate "Apple SMC Chamshell support"
+	depends on MACSMC_ACPI
+	help
+	  Say Y here if you want support for Apple SMC Chamshell (LID) sensor
+	  driver.
+
+	  If unsure, say Y.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called macsmc-chamshell.
+
 config INPUT_M68K_BEEP
 	tristate "M68k Beeper support"
 	depends on M68K
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 415fc4e2918b..69e02bf8ce7e 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_INPUT_IQS626A)		+= iqs626a.o
 obj-$(CONFIG_INPUT_IQS7222)		+= iqs7222.o
 obj-$(CONFIG_INPUT_KEYSPAN_REMOTE)	+= keyspan_remote.o
 obj-$(CONFIG_INPUT_KXTJ9)		+= kxtj9.o
+obj-$(CONFIG_INPUT_MACSMC_CHAMSHELL)	+= macsmc-chamshell.o
 obj-$(CONFIG_INPUT_M68K_BEEP)		+= m68kspkr.o
 obj-$(CONFIG_INPUT_MAX7360_ROTARY)	+= max7360-rotary.o
 obj-$(CONFIG_INPUT_MAX77650_ONKEY)	+= max77650-onkey.o
diff --git a/drivers/input/misc/macsmc-chamshell.c b/drivers/input/misc/macsmc-chamshell.c
new file mode 100644
index 000000000000..b7e538050487
--- /dev/null
+++ b/drivers/input/misc/macsmc-chamshell.c
@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/*
+ * Apple SMC Chamshell driver
+ *
+ * Copyright (C) 2026 Atharva Tiwari <atharvatiwarilinuxdev@gmail.com>
+ */
+
+#include <linux/input.h>
+#include <linux/mfd/macsmc.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define CHAMSHELL_KEY	SMC_KEY(MSLD)
+#define CHAMSHELL_POLL_INTERVAL 500
+
+struct macsmc_chamshell {
+	struct apple_smc *smc;
+	u8 last_state;
+};
+
+static void macsmc_chamshell_poll(struct input_dev *input)
+{
+	struct macsmc_chamshell *chamshell = input_get_drvdata(input);
+	u8 val;
+	int ret;
+
+	ret = apple_smc_read_u8(chamshell->smc, CHAMSHELL_KEY, &val);
+	if (ret)
+		return;
+
+	/* Normalize the lid state to 0 or 1.
+	 * I'm not sure if the SMC reports values other than 0,
+	 * but I do know that 0 means the lid is open.
+	 */
+	val = !!val;
+
+	if (val != chamshell->last_state) {
+		chamshell->last_state = val;
+		input_report_switch(input, SW_LID, val);
+		input_sync(input);
+	}
+}
+
+static int macsmc_chamshell_probe(struct platform_device *pdev)
+{
+	struct macsmc_chamshell *chamshell;
+	struct input_dev *input;
+	int ret;
+
+	chamshell = devm_kzalloc(&pdev->dev, sizeof(*chamshell), GFP_KERNEL);
+	if (!chamshell)
+		return -ENOMEM;
+
+	input = devm_input_allocate_device(&pdev->dev);
+	if (!input)
+		return -ENOMEM;
+
+	chamshell->smc = dev_get_drvdata(pdev->dev.parent);
+	if (!chamshell->smc)
+		return -ENODEV;
+
+	if (!apple_smc_key_exists(chamshell->smc, CHAMSHELL_KEY))
+		return -ENODEV;
+
+	input->name = "macsmc-chamshell";
+	input->id.bustype = BUS_HOST;
+
+	input_set_capability(input, EV_SW, SW_LID);
+	input_set_drvdata(input, chamshell);
+
+	ret = input_setup_polling(input, macsmc_chamshell_poll);
+	if (ret)
+		return ret;
+
+	input_set_poll_interval(input, CHAMSHELL_POLL_INTERVAL);
+
+	ret = input_register_device(input);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, chamshell);
+	return 0;
+}
+
+static struct platform_driver macsmc_chamshell_platform_driver = {
+	.probe = macsmc_chamshell_probe,
+	.driver = {
+		.name = "macsmc-chamshell",
+	},
+};
+
+module_platform_driver(macsmc_chamshell_platform_driver);
+
+MODULE_LICENSE("Dual MIT/GPL");
+MODULE_DESCRIPTION("Apple SMC Chamshell driver");
+MODULE_AUTHOR("Atharva Tiwari <atharvatiwarilinuxdev@gmail.com>");
+MODULE_ALIAS("platform:macsmc-chamshell");
diff --git a/drivers/mfd/macsmc-core.c b/drivers/mfd/macsmc-core.c
index ad5f5f7c050a..e1a334e06e32 100644
--- a/drivers/mfd/macsmc-core.c
+++ b/drivers/mfd/macsmc-core.c
@@ -22,6 +22,7 @@ static const struct mfd_cell apple_smc_devs[] = {
 
 static const struct mfd_cell apple_smc_acpi_devs[] = {
 	MFD_CELL_NAME("macsmc-accel"),
+	MFD_CELL_NAME("macsmc-chamshell"),
 	MFD_CELL_NAME("macsmc-hwmon"),
 	MFD_CELL_NAME("macsmc-led"),
 	MFD_CELL_NAME("macsmc-light"),
-- 
2.43.0