| /* |
| * 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> |
| #include <linux/apple_bl.h> |
| #include <linux/slab.h> |
| #include <linux/delay.h> |
| #include <acpi/video.h> |
| #include <asm/io.h> |
| |
| struct apple_gmux_data { |
| unsigned long iostart; |
| unsigned long iolen; |
| bool indexed; |
| struct mutex index_lock; |
| |
| 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_PORT_VALUE 0xc2 |
| #define GMUX_PORT_READ 0xd0 |
| #define GMUX_PORT_WRITE 0xd4 |
| |
| #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 u8 gmux_pio_read8(struct apple_gmux_data *gmux_data, int port) |
| { |
| return inb(gmux_data->iostart + port); |
| } |
| |
| static void gmux_pio_write8(struct apple_gmux_data *gmux_data, int port, |
| u8 val) |
| { |
| outb(val, gmux_data->iostart + port); |
| } |
| |
| static u32 gmux_pio_read32(struct apple_gmux_data *gmux_data, int port) |
| { |
| return inl(gmux_data->iostart + port); |
| } |
| |
| static void gmux_pio_write32(struct apple_gmux_data *gmux_data, int port, |
| u32 val) |
| { |
| int i; |
| u8 tmpval; |
| |
| for (i = 0; i < 4; i++) { |
| tmpval = (val >> (i * 8)) & 0xff; |
| outb(tmpval, port + i); |
| } |
| } |
| |
| static int gmux_index_wait_ready(struct apple_gmux_data *gmux_data) |
| { |
| int i = 200; |
| u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); |
| |
| while (i && (gwr & 0x01)) { |
| inb(gmux_data->iostart + GMUX_PORT_READ); |
| gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); |
| udelay(100); |
| i--; |
| } |
| |
| return !!i; |
| } |
| |
| static int gmux_index_wait_complete(struct apple_gmux_data *gmux_data) |
| { |
| int i = 200; |
| u8 gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); |
| |
| while (i && !(gwr & 0x01)) { |
| gwr = inb(gmux_data->iostart + GMUX_PORT_WRITE); |
| udelay(100); |
| i--; |
| } |
| |
| if (gwr & 0x01) |
| inb(gmux_data->iostart + GMUX_PORT_READ); |
| |
| return !!i; |
| } |
| |
| static u8 gmux_index_read8(struct apple_gmux_data *gmux_data, int port) |
| { |
| u8 val; |
| |
| mutex_lock(&gmux_data->index_lock); |
| outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ); |
| gmux_index_wait_ready(gmux_data); |
| val = inb(gmux_data->iostart + GMUX_PORT_VALUE); |
| mutex_unlock(&gmux_data->index_lock); |
| |
| return val; |
| } |
| |
| static void gmux_index_write8(struct apple_gmux_data *gmux_data, int port, |
| u8 val) |
| { |
| mutex_lock(&gmux_data->index_lock); |
| outb(val, gmux_data->iostart + GMUX_PORT_VALUE); |
| gmux_index_wait_ready(gmux_data); |
| outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE); |
| gmux_index_wait_complete(gmux_data); |
| mutex_unlock(&gmux_data->index_lock); |
| } |
| |
| static u32 gmux_index_read32(struct apple_gmux_data *gmux_data, int port) |
| { |
| u32 val; |
| |
| mutex_lock(&gmux_data->index_lock); |
| outb((port & 0xff), gmux_data->iostart + GMUX_PORT_READ); |
| gmux_index_wait_ready(gmux_data); |
| val = inl(gmux_data->iostart + GMUX_PORT_VALUE); |
| mutex_unlock(&gmux_data->index_lock); |
| |
| return val; |
| } |
| |
| static void gmux_index_write32(struct apple_gmux_data *gmux_data, int port, |
| u32 val) |
| { |
| int i; |
| u8 tmpval; |
| |
| mutex_lock(&gmux_data->index_lock); |
| |
| for (i = 0; i < 4; i++) { |
| tmpval = (val >> (i * 8)) & 0xff; |
| outb(tmpval, gmux_data->iostart + GMUX_PORT_VALUE + i); |
| } |
| |
| gmux_index_wait_ready(gmux_data); |
| outb(port & 0xff, gmux_data->iostart + GMUX_PORT_WRITE); |
| gmux_index_wait_complete(gmux_data); |
| mutex_unlock(&gmux_data->index_lock); |
| } |
| |
| static u8 gmux_read8(struct apple_gmux_data *gmux_data, int port) |
| { |
| if (gmux_data->indexed) |
| return gmux_index_read8(gmux_data, port); |
| else |
| return gmux_pio_read8(gmux_data, port); |
| } |
| |
| static void gmux_write8(struct apple_gmux_data *gmux_data, int port, u8 val) |
| { |
| if (gmux_data->indexed) |
| gmux_index_write8(gmux_data, port, val); |
| else |
| gmux_pio_write8(gmux_data, port, val); |
| } |
| |
| static u32 gmux_read32(struct apple_gmux_data *gmux_data, int port) |
| { |
| if (gmux_data->indexed) |
| return gmux_index_read32(gmux_data, port); |
| else |
| return gmux_pio_read32(gmux_data, port); |
| } |
| |
| static void gmux_write32(struct apple_gmux_data *gmux_data, int port, |
| u32 val) |
| { |
| if (gmux_data->indexed) |
| gmux_index_write32(gmux_data, port, val); |
| else |
| gmux_pio_write32(gmux_data, port, val); |
| } |
| |
| static bool gmux_is_indexed(struct apple_gmux_data *gmux_data) |
| { |
| u16 val; |
| |
| outb(0xaa, gmux_data->iostart + 0xcc); |
| outb(0x55, gmux_data->iostart + 0xcd); |
| outb(0x00, gmux_data->iostart + 0xce); |
| |
| val = inb(gmux_data->iostart + 0xcc) | |
| (inb(gmux_data->iostart + 0xcd) << 8); |
| |
| if (val == 0x55aa) |
| return true; |
| |
| return false; |
| } |
| |
| 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; |
| |
| if (bd->props.state & BL_CORE_SUSPENDED) |
| return 0; |
| |
| gmux_write32(gmux_data, GMUX_PORT_BRIGHTNESS, brightness); |
| |
| return 0; |
| } |
| |
| static const struct backlight_ops gmux_bl_ops = { |
| .options = BL_CORE_SUSPENDRESUME, |
| .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; |
| } |
| |
| /* |
| * Invalid version information may indicate either that the gmux |
| * device isn't present or that it's a new one that uses indexed |
| * io |
| */ |
| |
| 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) { |
| if (gmux_is_indexed(gmux_data)) { |
| mutex_init(&gmux_data->index_lock); |
| gmux_data->indexed = true; |
| } else { |
| pr_info("gmux device not present\n"); |
| ret = -ENODEV; |
| goto err_release; |
| } |
| pr_info("Found indexed gmux\n"); |
| } else { |
| 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); |
| |
| /* |
| * The backlight situation on Macs is complicated. If the gmux is |
| * present it's the best choice, because it always works for |
| * backlight control and supports more levels than other options. |
| * Disable the other backlight choices. |
| */ |
| acpi_video_dmi_promote_vendor(); |
| #if defined (CONFIG_ACPI_VIDEO) || defined (CONFIG_ACPI_VIDEO_MODULE) |
| acpi_video_unregister(); |
| #endif |
| apple_bl_unregister(); |
| |
| 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); |
| |
| acpi_video_dmi_demote_vendor(); |
| #if defined (CONFIG_ACPI_VIDEO) || defined (CONFIG_ACPI_VIDEO_MODULE) |
| acpi_video_register(); |
| #endif |
| apple_bl_register(); |
| } |
| |
| 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); |