2 files changed, 124 insertions, 0 deletions
diff --git a/arch/x86/platform/iris/Makefile b/arch/x86/platform/iris/Makefile
new file mode 100644
index 000000000..354352748
--- /dev/null
+++ b/arch/x86/platform/iris/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_X86_32_IRIS)		+= iris.o
diff --git a/arch/x86/platform/iris/iris.c b/arch/x86/platform/iris/iris.c
new file mode 100644
index 000000000..b42bfdab0
--- /dev/null
+++ b/arch/x86/platform/iris/iris.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Eurobraille/Iris power off support.
+ *
+ * Eurobraille's Iris machine is a PC with no APM or ACPI support.
+ * It is shutdown by a special I/O sequence which this module provides.
+ *
+ *  Copyright (C) Shérab <Sebastien.Hinderer@ens-lyon.org>
+ */
+
+#include <linux/moduleparam.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/pm.h>
+#include <asm/io.h>
+
+#define IRIS_GIO_BASE		0x340
+#define IRIS_GIO_INPUT		IRIS_GIO_BASE
+#define IRIS_GIO_OUTPUT		(IRIS_GIO_BASE + 1)
+#define IRIS_GIO_PULSE		0x80 /* First byte to send */
+#define IRIS_GIO_REST		0x00 /* Second byte to send */
+#define IRIS_GIO_NODEV		0xff /* Likely not an Iris */
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sébastien Hinderer <Sebastien.Hinderer@ens-lyon.org>");
+MODULE_DESCRIPTION("A power_off handler for Iris devices from EuroBraille");
+
+static bool force;
+
+module_param(force, bool, 0);
+MODULE_PARM_DESC(force, "Set to one to force poweroff handler installation.");
+
+static void (*old_pm_power_off)(void);
+
+static void iris_power_off(void)
+{
+	outb(IRIS_GIO_PULSE, IRIS_GIO_OUTPUT);
+	msleep(850);
+	outb(IRIS_GIO_REST, IRIS_GIO_OUTPUT);
+}
+
+/*
+ * Before installing the power_off handler, try to make sure the OS is
+ * running on an Iris.  Since Iris does not support DMI, this is done
+ * by reading its input port and seeing whether the read value is
+ * meaningful.
+ */
+static int iris_probe(struct platform_device *pdev)
+{
+	unsigned char status = inb(IRIS_GIO_INPUT);
+	if (status == IRIS_GIO_NODEV) {
+		printk(KERN_ERR "This machine does not seem to be an Iris. "
+			"Power off handler not installed.\n");
+		return -ENODEV;
+	}
+	old_pm_power_off = pm_power_off;
+	pm_power_off = &iris_power_off;
+	printk(KERN_INFO "Iris power_off handler installed.\n");
+	return 0;
+}
+
+static int iris_remove(struct platform_device *pdev)
+{
+	pm_power_off = old_pm_power_off;
+	printk(KERN_INFO "Iris power_off handler uninstalled.\n");
+	return 0;
+}
+
+static struct platform_driver iris_driver = {
+	.driver		= {
+		.name   = "iris",
+	},
+	.probe          = iris_probe,
+	.remove         = iris_remove,
+};
+
+static struct resource iris_resources[] = {
+	{
+		.start  = IRIS_GIO_BASE,
+		.end    = IRIS_GIO_OUTPUT,
+		.flags  = IORESOURCE_IO,
+		.name   = "address"
+	}
+};
+
+static struct platform_device *iris_device;
+
+static int iris_init(void)
+{
+	int ret;
+	if (force != 1) {
+		printk(KERN_ERR "The force parameter has not been set to 1."
+			" The Iris poweroff handler will not be installed.\n");
+		return -ENODEV;
+	}
+	ret = platform_driver_register(&iris_driver);
+	if (ret < 0) {
+		printk(KERN_ERR "Failed to register iris platform driver: %d\n",
+			ret);
+		return ret;
+	}
+	iris_device = platform_device_register_simple("iris", (-1),
+				iris_resources, ARRAY_SIZE(iris_resources));
+	if (IS_ERR(iris_device)) {
+		printk(KERN_ERR "Failed to register iris platform device\n");
+		platform_driver_unregister(&iris_driver);
+		return PTR_ERR(iris_device);
+	}
+	return 0;
+}
+
+static void iris_exit(void)
+{
+	platform_device_unregister(iris_device);
+	platform_driver_unregister(&iris_driver);
+}
+
+module_init(iris_init);
+module_exit(iris_exit);