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authorPaul Fox <pgf@laptop.org>2011-02-03 16:27:55 +0000
committerMatthew Garrett <mjg@redhat.com>2011-03-28 06:05:14 -0400
commit89ca11771a4b50ed616ab6c37e0ef333d02f1d47 (patch)
treea0cd71e287e22500abe7848d6e840e9034d3281c /drivers/platform/x86/xo15-ebook.c
parent18bcd0c8cb7d85a9063b88ec810dc1cdc0974518 (diff)
OLPC XO-1.5 ebook switch driver
The OLPC XO-1.5 has an ebook switch, triggered when the laptop screen is rotated then folding down, converting the device into ebook form. This switch is exposed through ACPI. Add a driver that exposes it to userspace as an input device. Signed-off-by: Daniel Drake <dsd@laptop.org> Acked-by: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Matthew Garrett <mjg@redhat.com>
Diffstat (limited to 'drivers/platform/x86/xo15-ebook.c')
-rw-r--r--drivers/platform/x86/xo15-ebook.c181
1 files changed, 181 insertions, 0 deletions
diff --git a/drivers/platform/x86/xo15-ebook.c b/drivers/platform/x86/xo15-ebook.c
new file mode 100644
index 000000000000..2343bb36e563
--- /dev/null
+++ b/drivers/platform/x86/xo15-ebook.c
@@ -0,0 +1,181 @@
+/*
+ * OLPC XO-1.5 ebook switch driver
+ * (based on generic ACPI button driver)
+ *
+ * Copyright (C) 2009 Paul Fox <pgf@laptop.org>
+ * Copyright (C) 2010 One Laptop per Child
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/input.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+
+#define MODULE_NAME "xo15-ebook"
+#define PREFIX MODULE_NAME ": "
+
+#define XO15_EBOOK_CLASS MODULE_NAME
+#define XO15_EBOOK_TYPE_UNKNOWN 0x00
+#define XO15_EBOOK_NOTIFY_STATUS 0x80
+
+#define XO15_EBOOK_SUBCLASS "ebook"
+#define XO15_EBOOK_HID "XO15EBK"
+#define XO15_EBOOK_DEVICE_NAME "EBook Switch"
+
+ACPI_MODULE_NAME(MODULE_NAME);
+
+MODULE_DESCRIPTION("OLPC XO-1.5 ebook switch driver");
+MODULE_LICENSE("GPL");
+
+static const struct acpi_device_id ebook_device_ids[] = {
+ { XO15_EBOOK_HID, 0 },
+ { "", 0 },
+};
+MODULE_DEVICE_TABLE(acpi, ebook_device_ids);
+
+struct ebook_switch {
+ struct input_dev *input;
+ char phys[32]; /* for input device */
+};
+
+static int ebook_send_state(struct acpi_device *device)
+{
+ struct ebook_switch *button = acpi_driver_data(device);
+ unsigned long long state;
+ acpi_status status;
+
+ status = acpi_evaluate_integer(device->handle, "EBK", NULL, &state);
+ if (ACPI_FAILURE(status))
+ return -EIO;
+
+ /* input layer checks if event is redundant */
+ input_report_switch(button->input, SW_TABLET_MODE, !state);
+ input_sync(button->input);
+ return 0;
+}
+
+static void ebook_switch_notify(struct acpi_device *device, u32 event)
+{
+ switch (event) {
+ case ACPI_FIXED_HARDWARE_EVENT:
+ case XO15_EBOOK_NOTIFY_STATUS:
+ ebook_send_state(device);
+ break;
+ default:
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Unsupported event [0x%x]\n", event));
+ break;
+ }
+}
+
+static int ebook_switch_resume(struct acpi_device *device)
+{
+ return ebook_send_state(device);
+}
+
+static int ebook_switch_add(struct acpi_device *device)
+{
+ struct ebook_switch *button;
+ struct input_dev *input;
+ const char *hid = acpi_device_hid(device);
+ char *name, *class;
+ int error;
+
+ button = kzalloc(sizeof(struct ebook_switch), GFP_KERNEL);
+ if (!button)
+ return -ENOMEM;
+
+ device->driver_data = button;
+
+ button->input = input = input_allocate_device();
+ if (!input) {
+ error = -ENOMEM;
+ goto err_free_button;
+ }
+
+ name = acpi_device_name(device);
+ class = acpi_device_class(device);
+
+ if (strcmp(hid, XO15_EBOOK_HID)) {
+ printk(KERN_ERR PREFIX "Unsupported hid [%s]\n", hid);
+ error = -ENODEV;
+ goto err_free_input;
+ }
+
+ strcpy(name, XO15_EBOOK_DEVICE_NAME);
+ sprintf(class, "%s/%s", XO15_EBOOK_CLASS, XO15_EBOOK_SUBCLASS);
+
+ snprintf(button->phys, sizeof(button->phys), "%s/button/input0", hid);
+
+ input->name = name;
+ input->phys = button->phys;
+ input->id.bustype = BUS_HOST;
+ input->dev.parent = &device->dev;
+
+ input->evbit[0] = BIT_MASK(EV_SW);
+ set_bit(SW_TABLET_MODE, input->swbit);
+
+ error = input_register_device(input);
+ if (error)
+ goto err_free_input;
+
+ ebook_send_state(device);
+
+ if (device->wakeup.flags.valid) {
+ /* Button's GPE is run-wake GPE */
+ acpi_enable_gpe(device->wakeup.gpe_device,
+ device->wakeup.gpe_number);
+ device->wakeup.run_wake_count++;
+ device_set_wakeup_enable(&device->dev, true);
+ }
+
+ return 0;
+
+ err_free_input:
+ input_free_device(input);
+ err_free_button:
+ kfree(button);
+ return error;
+}
+
+static int ebook_switch_remove(struct acpi_device *device, int type)
+{
+ struct ebook_switch *button = acpi_driver_data(device);
+
+ input_unregister_device(button->input);
+ kfree(button);
+ return 0;
+}
+
+static struct acpi_driver xo15_ebook_driver = {
+ .name = MODULE_NAME,
+ .class = XO15_EBOOK_CLASS,
+ .ids = ebook_device_ids,
+ .ops = {
+ .add = ebook_switch_add,
+ .resume = ebook_switch_resume,
+ .remove = ebook_switch_remove,
+ .notify = ebook_switch_notify,
+ },
+};
+
+static int __init xo15_ebook_init(void)
+{
+ return acpi_bus_register_driver(&xo15_ebook_driver);
+}
+
+static void __exit xo15_ebook_exit(void)
+{
+ acpi_bus_unregister_driver(&xo15_ebook_driver);
+}
+
+module_init(xo15_ebook_init);
+module_exit(xo15_ebook_exit);