+++ /dev/null
-/*
- * Gmux driver for Apple laptops
- *
- * Copyright (C) Canonical Ltd. <seth.forshee@canonical.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/backlight.h>
-#include <linux/acpi.h>
-#include <linux/pnp.h>
-
-struct apple_gmux_data {
- unsigned long iostart;
- unsigned long iolen;
-
- struct backlight_device *bdev;
-};
-
-/*
- * gmux port offsets. Many of these are not yet used, but may be in the
- * future, and it's useful to have them documented here anyhow.
- */
-#define GMUX_PORT_VERSION_MAJOR 0x04
-#define GMUX_PORT_VERSION_MINOR 0x05
-#define GMUX_PORT_VERSION_RELEASE 0x06
-#define GMUX_PORT_SWITCH_DISPLAY 0x10
-#define GMUX_PORT_SWITCH_GET_DISPLAY 0x11
-#define GMUX_PORT_INTERRUPT_ENABLE 0x14
-#define GMUX_PORT_INTERRUPT_STATUS 0x16
-#define GMUX_PORT_SWITCH_DDC 0x28
-#define GMUX_PORT_SWITCH_EXTERNAL 0x40
-#define GMUX_PORT_SWITCH_GET_EXTERNAL 0x41
-#define GMUX_PORT_DISCRETE_POWER 0x50
-#define GMUX_PORT_MAX_BRIGHTNESS 0x70
-#define GMUX_PORT_BRIGHTNESS 0x74
-
-#define GMUX_MIN_IO_LEN (GMUX_PORT_BRIGHTNESS + 4)
-
-#define GMUX_INTERRUPT_ENABLE 0xff
-#define GMUX_INTERRUPT_DISABLE 0x00
-
-#define GMUX_INTERRUPT_STATUS_ACTIVE 0
-#define GMUX_INTERRUPT_STATUS_DISPLAY (1 << 0)
-#define GMUX_INTERRUPT_STATUS_POWER (1 << 2)
-#define GMUX_INTERRUPT_STATUS_HOTPLUG (1 << 3)
-
-#define GMUX_BRIGHTNESS_MASK 0x00ffffff
-#define GMUX_MAX_BRIGHTNESS GMUX_BRIGHTNESS_MASK
-
-static inline u8 gmux_read8(struct apple_gmux_data *gmux_data, int port)
-{
- return inb(gmux_data->iostart + port);
-}
-
-static inline void gmux_write8(struct apple_gmux_data *gmux_data, int port,
- u8 val)
-{
- outb(val, gmux_data->iostart + port);
-}
-
-static inline u32 gmux_read32(struct apple_gmux_data *gmux_data, int port)
-{
- return inl(gmux_data->iostart + port);
-}
-
-static int gmux_get_brightness(struct backlight_device *bd)
-{
- struct apple_gmux_data *gmux_data = bl_get_data(bd);
- return gmux_read32(gmux_data, GMUX_PORT_BRIGHTNESS) &
- GMUX_BRIGHTNESS_MASK;
-}
-
-static int gmux_update_status(struct backlight_device *bd)
-{
- struct apple_gmux_data *gmux_data = bl_get_data(bd);
- u32 brightness = bd->props.brightness;
-
- /*
- * Older gmux versions require writing out lower bytes first then
- * setting the upper byte to 0 to flush the values. Newer versions
- * accept a single u32 write, but the old method also works, so we
- * just use the old method for all gmux versions.
- */
- gmux_write8(gmux_data, GMUX_PORT_BRIGHTNESS, brightness);
- gmux_write8(gmux_data, GMUX_PORT_BRIGHTNESS + 1, brightness >> 8);
- gmux_write8(gmux_data, GMUX_PORT_BRIGHTNESS + 2, brightness >> 16);
- gmux_write8(gmux_data, GMUX_PORT_BRIGHTNESS + 3, 0);
-
- return 0;
-}
-
-static const struct backlight_ops gmux_bl_ops = {
- .get_brightness = gmux_get_brightness,
- .update_status = gmux_update_status,
-};
-
-static int __devinit gmux_probe(struct pnp_dev *pnp,
- const struct pnp_device_id *id)
-{
- struct apple_gmux_data *gmux_data;
- struct resource *res;
- struct backlight_properties props;
- struct backlight_device *bdev;
- u8 ver_major, ver_minor, ver_release;
- int ret = -ENXIO;
-
- gmux_data = kzalloc(sizeof(*gmux_data), GFP_KERNEL);
- if (!gmux_data)
- return -ENOMEM;
- pnp_set_drvdata(pnp, gmux_data);
-
- res = pnp_get_resource(pnp, IORESOURCE_IO, 0);
- if (!res) {
- pr_err("Failed to find gmux I/O resource\n");
- goto err_free;
- }
-
- gmux_data->iostart = res->start;
- gmux_data->iolen = res->end - res->start;
-
- if (gmux_data->iolen < GMUX_MIN_IO_LEN) {
- pr_err("gmux I/O region too small (%lu < %u)\n",
- gmux_data->iolen, GMUX_MIN_IO_LEN);
- goto err_free;
- }
-
- if (!request_region(gmux_data->iostart, gmux_data->iolen,
- "Apple gmux")) {
- pr_err("gmux I/O already in use\n");
- goto err_free;
- }
-
- /*
- * On some machines the gmux is in ACPI even thought the machine
- * doesn't really have a gmux. Check for invalid version information
- * to detect this.
- */
- ver_major = gmux_read8(gmux_data, GMUX_PORT_VERSION_MAJOR);
- ver_minor = gmux_read8(gmux_data, GMUX_PORT_VERSION_MINOR);
- ver_release = gmux_read8(gmux_data, GMUX_PORT_VERSION_RELEASE);
- if (ver_major == 0xff && ver_minor == 0xff && ver_release == 0xff) {
- pr_info("gmux device not present\n");
- ret = -ENODEV;
- goto err_release;
- }
-
- pr_info("Found gmux version %d.%d.%d\n", ver_major, ver_minor,
- ver_release);
-
- memset(&props, 0, sizeof(props));
- props.type = BACKLIGHT_PLATFORM;
- props.max_brightness = gmux_read32(gmux_data, GMUX_PORT_MAX_BRIGHTNESS);
-
- /*
- * Currently it's assumed that the maximum brightness is less than
- * 2^24 for compatibility with old gmux versions. Cap the max
- * brightness at this value, but print a warning if the hardware
- * reports something higher so that it can be fixed.
- */
- if (WARN_ON(props.max_brightness > GMUX_MAX_BRIGHTNESS))
- props.max_brightness = GMUX_MAX_BRIGHTNESS;
-
- bdev = backlight_device_register("gmux_backlight", &pnp->dev,
- gmux_data, &gmux_bl_ops, &props);
- if (IS_ERR(bdev)) {
- ret = PTR_ERR(bdev);
- goto err_release;
- }
-
- gmux_data->bdev = bdev;
- bdev->props.brightness = gmux_get_brightness(bdev);
- backlight_update_status(bdev);
-
- return 0;
-
-err_release:
- release_region(gmux_data->iostart, gmux_data->iolen);
-err_free:
- kfree(gmux_data);
- return ret;
-}
-
-static void __devexit gmux_remove(struct pnp_dev *pnp)
-{
- struct apple_gmux_data *gmux_data = pnp_get_drvdata(pnp);
-
- backlight_device_unregister(gmux_data->bdev);
- release_region(gmux_data->iostart, gmux_data->iolen);
- kfree(gmux_data);
-}
-
-static const struct pnp_device_id gmux_device_ids[] = {
- {"APP000B", 0},
- {"", 0}
-};
-
-static struct pnp_driver gmux_pnp_driver = {
- .name = "apple-gmux",
- .probe = gmux_probe,
- .remove = __devexit_p(gmux_remove),
- .id_table = gmux_device_ids,
-};
-
-static int __init apple_gmux_init(void)
-{
- return pnp_register_driver(&gmux_pnp_driver);
-}
-
-static void __exit apple_gmux_exit(void)
-{
- pnp_unregister_driver(&gmux_pnp_driver);
-}
-
-module_init(apple_gmux_init);
-module_exit(apple_gmux_exit);
-
-MODULE_AUTHOR("Seth Forshee <seth.forshee@canonical.com>");
-MODULE_DESCRIPTION("Apple Gmux Driver");
-MODULE_LICENSE("GPL");
-MODULE_DEVICE_TABLE(pnp, gmux_device_ids);
projects / linux-flexiantxendom0.git / commitdiff