// SPDX-License-Identifier: GPL-2.0-or-later
/*
* DMI based code to deal with broken DSDTs on X86 tablets which ship with
* Android as (part of) the factory image. The factory kernels shipped on these
* devices typically have a bunch of things hardcoded, rather than specified
* in their DSDT.
*
* Copyright (C) 2021-2023 Hans de Goede <[email protected]>
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/acpi.h>
#include <linux/dmi.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/machine.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/serdev.h>
#include <linux/string.h>
#include "x86-android-tablets.h"
#include "../serdev_helpers.h"
static struct platform_device *x86_android_tablet_device;
/*
* This helper allows getting a GPIO descriptor *before* the actual device
* consuming it has been instantiated. This function MUST only be used to
* handle this special case such as, e.g.:
*
* 1. Getting an IRQ from a GPIO for i2c_board_info.irq which is passed to
* i2c_client_new() to instantiate i2c_client-s; or
* 2. Calling desc_to_gpio() to get an old style GPIO number for gpio-keys
* platform_data which still uses old style GPIO numbers.
*
* Since the consuming device has not been instantiated yet a dynamic lookup
* is generated using the special x86_android_tablet device for dev_id.
*
* For normal GPIO lookups a standard static struct gpiod_lookup_table MUST be used.
*/
int x86_android_tablet_get_gpiod(const char *chip, int pin, const char *con_id,
bool active_low, enum gpiod_flags dflags,
struct gpio_desc **desc)
{
struct gpiod_lookup_table *lookup;
struct gpio_desc *gpiod;
lookup = kzalloc(struct_size(lookup, table, 2), GFP_KERNEL);
if (!lookup)
return -ENOMEM;
lookup->dev_id = KBUILD_MODNAME;
lookup->table[0] =
GPIO_LOOKUP(chip, pin, con_id, active_low ? GPIO_ACTIVE_LOW : GPIO_ACTIVE_HIGH);
gpiod_add_lookup_table(lookup);
gpiod = devm_gpiod_get(&x86_android_tablet_device->dev, con_id, dflags);
gpiod_remove_lookup_table(lookup);
kfree(lookup);
if (IS_ERR(gpiod)) {
pr_err("error %ld getting GPIO %s %d\n", PTR_ERR(gpiod), chip, pin);
return PTR_ERR(gpiod);
}
if (desc)
*desc = gpiod;
return 0;
}
int x86_acpi_irq_helper_get(const struct x86_acpi_irq_data *data)
{
struct irq_fwspec fwspec = { };
struct irq_domain *domain;
struct acpi_device *adev;
struct gpio_desc *gpiod;
unsigned int irq_type;
acpi_handle handle;
acpi_status status;
int irq, ret;
switch (data->type) {
case X86_ACPI_IRQ_TYPE_APIC:
/*
* The DSDT may already reference the GSI in a device skipped by
* acpi_quirk_skip_i2c_client_enumeration(). Unregister the GSI
* to avoid -EBUSY errors in this case.
*/
acpi_unregister_gsi(data->index);
irq = acpi_register_gsi(NULL, data->index, data->trigger, data->polarity);
if (irq < 0)
pr_err("error %d getting APIC IRQ %d\n", irq, data->index);
return irq;
case X86_ACPI_IRQ_TYPE_GPIOINT:
/* Like acpi_dev_gpio_irq_get(), but without parsing ACPI resources */
ret = x86_android_tablet_get_gpiod(data->chip, data->index, data->con_id,
false, GPIOD_ASIS, &gpiod);
if (ret)
return ret;
irq = gpiod_to_irq(gpiod);
if (irq < 0) {
pr_err("error %d getting IRQ %s %d\n", irq, data->chip, data->index);
return irq;
}
irq_type = acpi_dev_get_irq_type(data->trigger, data->polarity);
if (irq_type != IRQ_TYPE_NONE && irq_type != irq_get_trigger_type(irq))
irq_set_irq_type(irq, irq_type);
if (data->free_gpio)
devm_gpiod_put(&x86_android_tablet_device->dev, gpiod);
return irq;
case X86_ACPI_IRQ_TYPE_PMIC:
status = acpi_get_handle(NULL, data->chip, &handle);
if (ACPI_FAILURE(status)) {
pr_err("error could not get %s handle\n", data->chip);
return -ENODEV;
}
adev = acpi_fetch_acpi_dev(handle);
if (!adev) {
pr_err("error could not get %s adev\n", data->chip);
return -ENODEV;
}
fwspec.fwnode = acpi_fwnode_handle(adev);
domain = irq_find_matching_fwspec(&fwspec, data->domain);
if (!domain) {
pr_err("error could not find IRQ domain for %s\n", data->chip);
return -ENODEV;
}
return irq_create_mapping(domain, data->index);
default:
return 0;
}
}
static int i2c_client_count;
static int spi_dev_count;
static int pdev_count;
static int serdev_count;
static struct i2c_client **i2c_clients;
static struct spi_device **spi_devs;
static struct platform_device **pdevs;
static struct serdev_device **serdevs;
static struct gpio_keys_button *buttons;
static struct gpiod_lookup_table * const *gpiod_lookup_tables;
static const struct software_node *bat_swnode;
static void (*exit_handler)(void);
static __init int x86_instantiate_i2c_client(const struct x86_dev_info *dev_info,
int idx)
{
const struct x86_i2c_client_info *client_info = &dev_info->i2c_client_info[idx];
struct i2c_board_info board_info = client_info->board_info;
struct i2c_adapter *adap;
acpi_handle handle;
acpi_status status;
board_info.irq = x86_acpi_irq_helper_get(&client_info->irq_data);
if (board_info.irq < 0)
return board_info.irq;
status = acpi_get_handle(NULL, client_info->adapter_path, &handle);
if (ACPI_FAILURE(status)) {
pr_err("Error could not get %s handle\n", client_info->adapter_path);
return -ENODEV;
}
adap = i2c_acpi_find_adapter_by_handle(handle);
if (!adap) {
pr_err("error could not get %s adapter\n", client_info->adapter_path);
return -ENODEV;
}
i2c_clients[idx] = i2c_new_client_device(adap, &board_info);
put_device(&adap->dev);
if (IS_ERR(i2c_clients[idx]))
return dev_err_probe(&adap->dev, PTR_ERR(i2c_clients[idx]),
"creating I2C-client %d\n", idx);
return 0;
}
static __init int x86_instantiate_spi_dev(const struct x86_dev_info *dev_info, int idx)
{
const struct x86_spi_dev_info *spi_dev_info = &dev_info->spi_dev_info[idx];
struct spi_board_info board_info = spi_dev_info->board_info;
struct spi_controller *controller;
struct acpi_device *adev;
acpi_handle handle;
acpi_status status;
board_info.irq = x86_acpi_irq_helper_get(&spi_dev_info->irq_data);
if (board_info.irq < 0)
return board_info.irq;
status = acpi_get_handle(NULL, spi_dev_info->ctrl_path, &handle);
if (ACPI_FAILURE(status)) {
pr_err("Error could not get %s handle\n", spi_dev_info->ctrl_path);
return -ENODEV;
}
adev = acpi_fetch_acpi_dev(handle);
if (!adev) {
pr_err("Error could not get adev for %s\n", spi_dev_info->ctrl_path);
return -ENODEV;
}
controller = acpi_spi_find_controller_by_adev(adev);
if (!controller) {
pr_err("Error could not get SPI controller for %s\n", spi_dev_info->ctrl_path);
return -ENODEV;
}
spi_devs[idx] = spi_new_device(controller, &board_info);
put_device(&controller->dev);
if (!spi_devs[idx])
return dev_err_probe(&controller->dev, -ENOMEM,
"creating SPI-device %d\n", idx);
return 0;
}
static __init int x86_instantiate_serdev(const struct x86_serdev_info *info, int idx)
{
struct acpi_device *serdev_adev;
struct serdev_device *serdev;
struct device *ctrl_dev;
int ret = -ENODEV;
ctrl_dev = get_serdev_controller(info->ctrl_hid, info->ctrl_uid, 0,
info->ctrl_devname);
if (IS_ERR(ctrl_dev))
return PTR_ERR(ctrl_dev);
serdev_adev = acpi_dev_get_first_match_dev(info->serdev_hid, NULL, -1);
if (!serdev_adev) {
pr_err("error could not get %s serdev adev\n", info->serdev_hid);
goto put_ctrl_dev;
}
serdev = serdev_device_alloc(to_serdev_controller(ctrl_dev));
if (!serdev) {
ret = -ENOMEM;
goto put_serdev_adev;
}
ACPI_COMPANION_SET(&serdev->dev, serdev_adev);
acpi_device_set_enumerated(serdev_adev);
ret = serdev_device_add(serdev);
if (ret) {
dev_err(&serdev->dev, "error %d adding serdev\n", ret);
serdev_device_put(serdev);
goto put_serdev_adev;
}
serdevs[idx] = serdev;
put_serdev_adev:
acpi_dev_put(serdev_adev);
put_ctrl_dev:
put_device(ctrl_dev);
return ret;
}
static void x86_android_tablet_remove(struct platform_device *pdev)
{
int i;
for (i = serdev_count - 1; i >= 0; i--) {
if (serdevs[i])
serdev_device_remove(serdevs[i]);
}
kfree(serdevs);
for (i = pdev_count - 1; i >= 0; i--)
platform_device_unregister(pdevs[i]);
kfree(pdevs);
kfree(buttons);
for (i = spi_dev_count - 1; i >= 0; i--)
spi_unregister_device(spi_devs[i]);
kfree(spi_devs);
for (i = i2c_client_count - 1; i >= 0; i--)
i2c_unregister_device(i2c_clients[i]);
kfree(i2c_clients);
if (exit_handler)
exit_handler();
for (i = 0; gpiod_lookup_tables && gpiod_lookup_tables[i]; i++)
gpiod_remove_lookup_table(gpiod_lookup_tables[i]);
software_node_unregister(bat_swnode);
}
static __init int x86_android_tablet_probe(struct platform_device *pdev)
{
const struct x86_dev_info *dev_info;
const struct dmi_system_id *id;
int i, ret = 0;
id = dmi_first_match(x86_android_tablet_ids);
if (!id)
return -ENODEV;
dev_info = id->driver_data;
/* Allow x86_android_tablet_device use before probe() exits */
x86_android_tablet_device = pdev;
/*
* Since this runs from module_init() it cannot use -EPROBE_DEFER,
* instead pre-load any modules which are listed as requirements.
*/
for (i = 0; dev_info->modules && dev_info->modules[i]; i++)
request_module(dev_info->modules[i]);
bat_swnode = dev_info->bat_swnode;
if (bat_swnode) {
ret = software_node_register(bat_swnode);
if (ret)
return ret;
}
gpiod_lookup_tables = dev_info->gpiod_lookup_tables;
for (i = 0; gpiod_lookup_tables && gpiod_lookup_tables[i]; i++)
gpiod_add_lookup_table(gpiod_lookup_tables[i]);
if (dev_info->init) {
ret = dev_info->init(&pdev->dev);
if (ret < 0) {
x86_android_tablet_remove(pdev);
return ret;
}
exit_handler = dev_info->exit;
}
i2c_clients = kcalloc(dev_info->i2c_client_count, sizeof(*i2c_clients), GFP_KERNEL);
if (!i2c_clients) {
x86_android_tablet_remove(pdev);
return -ENOMEM;
}
i2c_client_count = dev_info->i2c_client_count;
for (i = 0; i < i2c_client_count; i++) {
ret = x86_instantiate_i2c_client(dev_info, i);
if (ret < 0) {
x86_android_tablet_remove(pdev);
return ret;
}
}
spi_devs = kcalloc(dev_info->spi_dev_count, sizeof(*spi_devs), GFP_KERNEL);
if (!spi_devs) {
x86_android_tablet_remove(pdev);
return -ENOMEM;
}
spi_dev_count = dev_info->spi_dev_count;
for (i = 0; i < spi_dev_count; i++) {
ret = x86_instantiate_spi_dev(dev_info, i);
if (ret < 0) {
x86_android_tablet_remove(pdev);
return ret;
}
}
/* + 1 to make space for the (optional) gpio_keys_button platform device */
pdevs = kcalloc(dev_info->pdev_count + 1, sizeof(*pdevs), GFP_KERNEL);
if (!pdevs) {
x86_android_tablet_remove(pdev);
return -ENOMEM;
}
pdev_count = dev_info->pdev_count;
for (i = 0; i < pdev_count; i++) {
pdevs[i] = platform_device_register_full(&dev_info->pdev_info[i]);
if (IS_ERR(pdevs[i])) {
x86_android_tablet_remove(pdev);
return PTR_ERR(pdevs[i]);
}
}
serdevs = kcalloc(dev_info->serdev_count, sizeof(*serdevs), GFP_KERNEL);
if (!serdevs) {
x86_android_tablet_remove(pdev);
return -ENOMEM;
}
serdev_count = dev_info->serdev_count;
for (i = 0; i < serdev_count; i++) {
ret = x86_instantiate_serdev(&dev_info->serdev_info[i], i);
if (ret < 0) {
x86_android_tablet_remove(pdev);
return ret;
}
}
if (dev_info->gpio_button_count) {
struct gpio_keys_platform_data pdata = { };
struct gpio_desc *gpiod;
buttons = kcalloc(dev_info->gpio_button_count, sizeof(*buttons), GFP_KERNEL);
if (!buttons) {
x86_android_tablet_remove(pdev);
return -ENOMEM;
}
for (i = 0; i < dev_info->gpio_button_count; i++) {
ret = x86_android_tablet_get_gpiod(dev_info->gpio_button[i].chip,
dev_info->gpio_button[i].pin,
dev_info->gpio_button[i].button.desc,
false, GPIOD_IN, &gpiod);
if (ret < 0) {
x86_android_tablet_remove(pdev);
return ret;
}
buttons[i] = dev_info->gpio_button[i].button;
buttons[i].gpio = desc_to_gpio(gpiod);
/* Release GPIO descriptor so that gpio-keys can request it */
devm_gpiod_put(&x86_android_tablet_device->dev, gpiod);
}
pdata.buttons = buttons;
pdata.nbuttons = dev_info->gpio_button_count;
pdevs[pdev_count] = platform_device_register_data(&pdev->dev, "gpio-keys",
PLATFORM_DEVID_AUTO,
&pdata, sizeof(pdata));
if (IS_ERR(pdevs[pdev_count])) {
x86_android_tablet_remove(pdev);
return PTR_ERR(pdevs[pdev_count]);
}
pdev_count++;
}
return 0;
}
static struct platform_driver x86_android_tablet_driver = {
.driver = {
.name = KBUILD_MODNAME,
},
.remove_new = x86_android_tablet_remove,
};
static int __init x86_android_tablet_init(void)
{
x86_android_tablet_device = platform_create_bundle(&x86_android_tablet_driver,
x86_android_tablet_probe,
NULL, 0, NULL, 0);
return PTR_ERR_OR_ZERO(x86_android_tablet_device);
}
module_init(x86_android_tablet_init);
static void __exit x86_android_tablet_exit(void)
{
platform_device_unregister(x86_android_tablet_device);
platform_driver_unregister(&x86_android_tablet_driver);
}
module_exit(x86_android_tablet_exit);
MODULE_AUTHOR("Hans de Goede <[email protected]>");
MODULE_DESCRIPTION("X86 Android tablets DSDT fixups driver");
MODULE_LICENSE("GPL");
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