// SPDX-License-Identifier: GPL-2.0
/*
* Generic Loongson processor based LAPTOP/ALL-IN-ONE driver
*
* Jianmin Lv <[email protected]>
* Huacai Chen <[email protected]>
*
* Copyright (C) 2022 Loongson Technology Corporation Limited
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/acpi.h>
#include <linux/backlight.h>
#include <linux/device.h>
#include <linux/input.h>
#include <linux/input/sparse-keymap.h>
#include <linux/platform_device.h>
#include <linux/string.h>
#include <linux/types.h>
#include <acpi/video.h>
/* 1. Driver-wide structs and misc. variables */
/* ACPI HIDs */
#define LOONGSON_ACPI_EC_HID "PNP0C09"
#define LOONGSON_ACPI_HKEY_HID "LOON0000"
#define ACPI_LAPTOP_NAME "loongson-laptop"
#define ACPI_LAPTOP_ACPI_EVENT_PREFIX "loongson"
#define MAX_ACPI_ARGS 3
#define GENERIC_HOTKEY_MAP_MAX 64
#define GENERIC_EVENT_TYPE_OFF 12
#define GENERIC_EVENT_TYPE_MASK 0xF000
#define GENERIC_EVENT_CODE_MASK 0x0FFF
struct generic_sub_driver {
u32 type;
char *name;
acpi_handle *handle;
struct acpi_device *device;
struct platform_driver *driver;
int (*init)(struct generic_sub_driver *sub_driver);
void (*notify)(struct generic_sub_driver *sub_driver, u32 event);
u8 acpi_notify_installed;
};
static u32 input_device_registered;
static struct input_dev *generic_inputdev;
static acpi_handle hotkey_handle;
static struct key_entry hotkey_keycode_map[GENERIC_HOTKEY_MAP_MAX];
int loongson_laptop_turn_on_backlight(void);
int loongson_laptop_turn_off_backlight(void);
static int loongson_laptop_backlight_update(struct backlight_device *bd);
/* 2. ACPI Helpers and device model */
static int acpi_evalf(acpi_handle handle, int *res, char *method, char *fmt, ...)
{
char res_type;
char *fmt0 = fmt;
va_list ap;
int success, quiet;
acpi_status status;
struct acpi_object_list params;
struct acpi_buffer result, *resultp;
union acpi_object in_objs[MAX_ACPI_ARGS], out_obj;
if (!*fmt) {
pr_err("acpi_evalf() called with empty format\n");
return 0;
}
if (*fmt == 'q') {
quiet = 1;
fmt++;
} else
quiet = 0;
res_type = *(fmt++);
params.count = 0;
params.pointer = &in_objs[0];
va_start(ap, fmt);
while (*fmt) {
char c = *(fmt++);
switch (c) {
case 'd': /* int */
in_objs[params.count].integer.value = va_arg(ap, int);
in_objs[params.count++].type = ACPI_TYPE_INTEGER;
break;
/* add more types as needed */
default:
pr_err("acpi_evalf() called with invalid format character '%c'\n", c);
va_end(ap);
return 0;
}
}
va_end(ap);
if (res_type != 'v') {
result.length = sizeof(out_obj);
result.pointer = &out_obj;
resultp = &result;
} else
resultp = NULL;
status = acpi_evaluate_object(handle, method, ¶ms, resultp);
switch (res_type) {
case 'd': /* int */
success = (status == AE_OK && out_obj.type == ACPI_TYPE_INTEGER);
if (success && res)
*res = out_obj.integer.value;
break;
case 'v': /* void */
success = status == AE_OK;
break;
/* add more types as needed */
default:
pr_err("acpi_evalf() called with invalid format character '%c'\n", res_type);
return 0;
}
if (!success && !quiet)
pr_err("acpi_evalf(%s, %s, ...) failed: %s\n",
method, fmt0, acpi_format_exception(status));
return success;
}
static int hotkey_status_get(int *status)
{
if (!acpi_evalf(hotkey_handle, status, "GSWS", "d"))
return -EIO;
return 0;
}
static void dispatch_acpi_notify(acpi_handle handle, u32 event, void *data)
{
struct generic_sub_driver *sub_driver = data;
if (!sub_driver || !sub_driver->notify)
return;
sub_driver->notify(sub_driver, event);
}
static int __init setup_acpi_notify(struct generic_sub_driver *sub_driver)
{
acpi_status status;
if (!*sub_driver->handle)
return 0;
sub_driver->device = acpi_fetch_acpi_dev(*sub_driver->handle);
if (!sub_driver->device) {
pr_err("acpi_fetch_acpi_dev(%s) failed\n", sub_driver->name);
return -ENODEV;
}
sub_driver->device->driver_data = sub_driver;
sprintf(acpi_device_class(sub_driver->device), "%s/%s",
ACPI_LAPTOP_ACPI_EVENT_PREFIX, sub_driver->name);
status = acpi_install_notify_handler(*sub_driver->handle,
sub_driver->type, dispatch_acpi_notify, sub_driver);
if (ACPI_FAILURE(status)) {
if (status == AE_ALREADY_EXISTS) {
pr_notice("Another device driver is already "
"handling %s events\n", sub_driver->name);
} else {
pr_err("acpi_install_notify_handler(%s) failed: %s\n",
sub_driver->name, acpi_format_exception(status));
}
return -ENODEV;
}
sub_driver->acpi_notify_installed = 1;
return 0;
}
static int loongson_hotkey_suspend(struct device *dev)
{
return 0;
}
static int loongson_hotkey_resume(struct device *dev)
{
int status = 0;
struct key_entry ke;
struct backlight_device *bd;
bd = backlight_device_get_by_type(BACKLIGHT_PLATFORM);
if (bd) {
loongson_laptop_backlight_update(bd) ?
pr_warn("Loongson_backlight: resume brightness failed") :
pr_info("Loongson_backlight: resume brightness %d\n", bd->props.brightness);
}
/*
* Only if the firmware supports SW_LID event model, we can handle the
* event. This is for the consideration of development board without EC.
*/
if (test_bit(SW_LID, generic_inputdev->swbit)) {
if (hotkey_status_get(&status) < 0)
return -EIO;
/*
* The input device sw element records the last lid status.
* When the system is awakened by other wake-up sources,
* the lid event will also be reported. The judgment of
* adding SW_LID bit which in sw element can avoid this
* case.
*
* Input system will drop lid event when current lid event
* value and last lid status in the same. So laptop driver
* doesn't report repeated events.
*
* Lid status is generally 0, but hardware exception is
* considered. So add lid status confirmation.
*/
if (test_bit(SW_LID, generic_inputdev->sw) && !(status & (1 << SW_LID))) {
ke.type = KE_SW;
ke.sw.value = (u8)status;
ke.sw.code = SW_LID;
sparse_keymap_report_entry(generic_inputdev, &ke, 1, true);
}
}
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(loongson_hotkey_pm,
loongson_hotkey_suspend, loongson_hotkey_resume);
static int loongson_hotkey_probe(struct platform_device *pdev)
{
hotkey_handle = ACPI_HANDLE(&pdev->dev);
if (!hotkey_handle)
return -ENODEV;
return 0;
}
static const struct acpi_device_id loongson_device_ids[] = {
{LOONGSON_ACPI_HKEY_HID, 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, loongson_device_ids);
static struct platform_driver loongson_hotkey_driver = {
.probe = loongson_hotkey_probe,
.driver = {
.name = "loongson-hotkey",
.owner = THIS_MODULE,
.pm = pm_ptr(&loongson_hotkey_pm),
.acpi_match_table = loongson_device_ids,
},
};
static int hotkey_map(void)
{
u32 index;
acpi_status status;
struct acpi_buffer buf;
union acpi_object *pack;
buf.length = ACPI_ALLOCATE_BUFFER;
status = acpi_evaluate_object_typed(hotkey_handle, "KMAP", NULL, &buf, ACPI_TYPE_PACKAGE);
if (status != AE_OK) {
pr_err("ACPI exception: %s\n", acpi_format_exception(status));
return -1;
}
pack = buf.pointer;
for (index = 0; index < pack->package.count; index++) {
union acpi_object *element, *sub_pack;
sub_pack = &pack->package.elements[index];
element = &sub_pack->package.elements[0];
hotkey_keycode_map[index].type = element->integer.value;
element = &sub_pack->package.elements[1];
hotkey_keycode_map[index].code = element->integer.value;
element = &sub_pack->package.elements[2];
hotkey_keycode_map[index].keycode = element->integer.value;
}
return 0;
}
static int hotkey_backlight_set(bool enable)
{
if (!acpi_evalf(hotkey_handle, NULL, "VCBL", "vd", enable ? 1 : 0))
return -EIO;
return 0;
}
static int ec_get_brightness(void)
{
int status = 0;
if (!hotkey_handle)
return -ENXIO;
if (!acpi_evalf(hotkey_handle, &status, "ECBG", "d"))
return -EIO;
return status;
}
static int ec_set_brightness(int level)
{
int ret = 0;
if (!hotkey_handle)
return -ENXIO;
if (!acpi_evalf(hotkey_handle, NULL, "ECBS", "vd", level))
ret = -EIO;
return ret;
}
static int ec_backlight_level(u8 level)
{
int status = 0;
if (!hotkey_handle)
return -ENXIO;
if (!acpi_evalf(hotkey_handle, &status, "ECLL", "d"))
return -EIO;
if ((status < 0) || (level > status))
return status;
if (!acpi_evalf(hotkey_handle, &status, "ECSL", "d"))
return -EIO;
if ((status < 0) || (level < status))
return status;
return level;
}
static int loongson_laptop_backlight_update(struct backlight_device *bd)
{
int lvl = ec_backlight_level(bd->props.brightness);
if (lvl < 0)
return -EIO;
if (ec_set_brightness(lvl))
return -EIO;
return 0;
}
static int loongson_laptop_get_brightness(struct backlight_device *bd)
{
int level;
level = ec_get_brightness();
if (level < 0)
return -EIO;
return level;
}
static const struct backlight_ops backlight_laptop_ops = {
.update_status = loongson_laptop_backlight_update,
.get_brightness = loongson_laptop_get_brightness,
};
static int laptop_backlight_register(void)
{
int status = 0;
struct backlight_properties props;
memset(&props, 0, sizeof(props));
if (!acpi_evalf(hotkey_handle, &status, "ECLL", "d"))
return -EIO;
props.brightness = 1;
props.max_brightness = status;
props.type = BACKLIGHT_PLATFORM;
backlight_device_register("loongson_laptop",
NULL, NULL, &backlight_laptop_ops, &props);
return 0;
}
int loongson_laptop_turn_on_backlight(void)
{
int status;
union acpi_object arg0 = { ACPI_TYPE_INTEGER };
struct acpi_object_list args = { 1, &arg0 };
arg0.integer.value = 1;
status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
if (ACPI_FAILURE(status)) {
pr_info("Loongson lvds error: 0x%x\n", status);
return -ENODEV;
}
return 0;
}
int loongson_laptop_turn_off_backlight(void)
{
int status;
union acpi_object arg0 = { ACPI_TYPE_INTEGER };
struct acpi_object_list args = { 1, &arg0 };
arg0.integer.value = 0;
status = acpi_evaluate_object(NULL, "\\BLSW", &args, NULL);
if (ACPI_FAILURE(status)) {
pr_info("Loongson lvds error: 0x%x\n", status);
return -ENODEV;
}
return 0;
}
static int __init event_init(struct generic_sub_driver *sub_driver)
{
int ret;
ret = hotkey_map();
if (ret < 0) {
pr_err("Failed to parse keymap from DSDT\n");
return ret;
}
ret = sparse_keymap_setup(generic_inputdev, hotkey_keycode_map, NULL);
if (ret < 0) {
pr_err("Failed to setup input device keymap\n");
input_free_device(generic_inputdev);
generic_inputdev = NULL;
return ret;
}
/*
* This hotkey driver handle backlight event when
* acpi_video_get_backlight_type() gets acpi_backlight_vendor
*/
if (acpi_video_get_backlight_type() == acpi_backlight_vendor)
hotkey_backlight_set(true);
else
hotkey_backlight_set(false);
pr_info("ACPI: enabling firmware HKEY event interface...\n");
return ret;
}
static void event_notify(struct generic_sub_driver *sub_driver, u32 event)
{
int type, scan_code;
struct key_entry *ke = NULL;
scan_code = event & GENERIC_EVENT_CODE_MASK;
type = (event & GENERIC_EVENT_TYPE_MASK) >> GENERIC_EVENT_TYPE_OFF;
ke = sparse_keymap_entry_from_scancode(generic_inputdev, scan_code);
if (ke) {
if (type == KE_SW) {
int status = 0;
if (hotkey_status_get(&status) < 0)
return;
ke->sw.value = !!(status & (1 << ke->sw.code));
}
sparse_keymap_report_entry(generic_inputdev, ke, 1, true);
}
}
/* 3. Infrastructure */
static void generic_subdriver_exit(struct generic_sub_driver *sub_driver);
static int __init generic_subdriver_init(struct generic_sub_driver *sub_driver)
{
int ret;
if (!sub_driver || !sub_driver->driver)
return -EINVAL;
ret = platform_driver_register(sub_driver->driver);
if (ret)
return -EINVAL;
if (sub_driver->init) {
ret = sub_driver->init(sub_driver);
if (ret)
goto err_out;
}
if (sub_driver->notify) {
ret = setup_acpi_notify(sub_driver);
if (ret == -ENODEV) {
ret = 0;
goto err_out;
}
if (ret < 0)
goto err_out;
}
return 0;
err_out:
generic_subdriver_exit(sub_driver);
return ret;
}
static void generic_subdriver_exit(struct generic_sub_driver *sub_driver)
{
if (sub_driver->acpi_notify_installed) {
acpi_remove_notify_handler(*sub_driver->handle,
sub_driver->type, dispatch_acpi_notify);
sub_driver->acpi_notify_installed = 0;
}
platform_driver_unregister(sub_driver->driver);
}
static struct generic_sub_driver generic_sub_drivers[] __refdata = {
{
.name = "hotkey",
.init = event_init,
.notify = event_notify,
.handle = &hotkey_handle,
.type = ACPI_DEVICE_NOTIFY,
.driver = &loongson_hotkey_driver,
},
};
static int __init generic_acpi_laptop_init(void)
{
bool ec_found;
int i, ret, status;
if (acpi_disabled)
return -ENODEV;
/* The EC device is required */
ec_found = acpi_dev_found(LOONGSON_ACPI_EC_HID);
if (!ec_found)
return -ENODEV;
/* Enable SCI for EC */
acpi_write_bit_register(ACPI_BITREG_SCI_ENABLE, 1);
generic_inputdev = input_allocate_device();
if (!generic_inputdev) {
pr_err("Unable to allocate input device\n");
return -ENOMEM;
}
/* Prepare input device, but don't register */
generic_inputdev->name =
"Loongson Generic Laptop/All-in-One Extra Buttons";
generic_inputdev->phys = ACPI_LAPTOP_NAME "/input0";
generic_inputdev->id.bustype = BUS_HOST;
generic_inputdev->dev.parent = NULL;
/* Init subdrivers */
for (i = 0; i < ARRAY_SIZE(generic_sub_drivers); i++) {
ret = generic_subdriver_init(&generic_sub_drivers[i]);
if (ret < 0) {
input_free_device(generic_inputdev);
while (--i >= 0)
generic_subdriver_exit(&generic_sub_drivers[i]);
return ret;
}
}
ret = input_register_device(generic_inputdev);
if (ret < 0) {
input_free_device(generic_inputdev);
while (--i >= 0)
generic_subdriver_exit(&generic_sub_drivers[i]);
pr_err("Unable to register input device\n");
return ret;
}
input_device_registered = 1;
if (acpi_evalf(hotkey_handle, &status, "ECBG", "d")) {
pr_info("Loongson Laptop used, init brightness is 0x%x\n", status);
ret = laptop_backlight_register();
if (ret < 0)
pr_err("Loongson Laptop: laptop-backlight device register failed\n");
}
return 0;
}
static void __exit generic_acpi_laptop_exit(void)
{
if (generic_inputdev) {
if (input_device_registered)
input_unregister_device(generic_inputdev);
else
input_free_device(generic_inputdev);
}
}
module_init(generic_acpi_laptop_init);
module_exit(generic_acpi_laptop_exit);
MODULE_AUTHOR("Jianmin Lv <[email protected]>");
MODULE_AUTHOR("Huacai Chen <[email protected]>");
MODULE_DESCRIPTION("Loongson Laptop/All-in-One ACPI Driver");
MODULE_LICENSE("GPL");
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