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/* SPDX-License-Identifier: GPL-2.0-only */
#include <acpi/acpi_device.h>
#include <acpi/acpigen.h>
#include <console/console.h>
#include <device/i2c_bus.h>
#include <device/i2c_simple.h>
#include <device/device.h>
#include <device/path.h>
#include <gpio.h>
#include <string.h>
#include "chip.h"
#if CONFIG(HAVE_ACPI_TABLES)
static bool i2c_generic_add_gpios_to_crs(struct drivers_i2c_generic_config *cfg)
{
/*
* Return false if:
* 1. Request to explicitly disable export of GPIOs in CRS, or
* 2. Both reset and enable GPIOs are not provided.
*/
if (cfg->disable_gpio_export_in_crs ||
((cfg->reset_gpio.pin_count == 0) &&
(cfg->enable_gpio.pin_count == 0)))
return false;
return true;
}
static int i2c_generic_write_gpio(struct acpi_gpio *gpio, int *curr_index)
{
int ret = -1;
if (gpio->pin_count == 0)
return ret;
acpi_device_write_gpio(gpio);
ret = *curr_index;
(*curr_index)++;
return ret;
}
void i2c_generic_fill_ssdt(const struct device *dev,
void (*callback)(const struct device *dev),
struct drivers_i2c_generic_config *config)
{
const char *scope = acpi_device_scope(dev);
struct acpi_i2c i2c = {
.address = dev->path.i2c.device,
.mode_10bit = dev->path.i2c.mode_10bit,
.speed = config->speed ? : I2C_SPEED_FAST,
.resource = scope,
};
struct acpi_dp *dsd = NULL;
int curr_index = 0;
int reset_gpio_index = -1, enable_gpio_index = -1, irq_gpio_index = -1;
const char *path = acpi_device_path(dev);
if (!scope)
return;
if (!config->hid) {
printk(BIOS_ERR, "%s: HID required but not set\n", dev_path(dev));
return;
}
if (config->detect) {
struct device *const busdev = i2c_busdev(dev);
if (!i2c_dev_detect(busdev, dev->path.i2c.device)) {
printk(BIOS_SPEW, "%s: %s at %s -- NOT FOUND, skipping\n",
path,
config->desc ? : dev->chip_ops->name,
dev_path(dev));
return;
}
}
if (config->has_power_resource && !config->disable_gpio_export_in_crs) {
/*
* This case will most likely cause timing problems. The OS driver might be
* controlling the GPIOs, but the ACPI Power Resource will also be controlling
* them. This will result in the two fighting and stomping on each other.
*/
printk(BIOS_ERR, "%s: Exposing GPIOs in Power Resource and _CRS\n",
dev_path(dev));
}
/* Device */
acpigen_write_scope(scope);
acpigen_write_device(acpi_device_name(dev));
acpigen_write_name_string("_HID", config->hid);
if (config->cid)
acpigen_write_name_string("_CID", config->cid);
acpigen_write_name_integer("_UID", config->uid);
if (config->desc)
acpigen_write_name_string("_DDN", config->desc);
acpigen_write_STA(acpi_device_status(dev));
/* Resources */
acpigen_write_name("_CRS");
acpigen_write_resourcetemplate_header();
acpi_device_write_i2c(&i2c);
/* Use either Interrupt() or GpioInt() */
if (config->irq_gpio.pin_count)
irq_gpio_index = i2c_generic_write_gpio(&config->irq_gpio,
&curr_index);
else
acpi_device_write_interrupt(&config->irq);
if (i2c_generic_add_gpios_to_crs(config) == true) {
reset_gpio_index = i2c_generic_write_gpio(&config->reset_gpio,
&curr_index);
enable_gpio_index = i2c_generic_write_gpio(&config->enable_gpio,
&curr_index);
}
acpigen_write_resourcetemplate_footer();
/* Wake capabilities */
if (config->wake) {
acpigen_write_name_integer("_S0W", ACPI_DEVICE_SLEEP_D3_HOT);
acpigen_write_PRW(config->wake, 3);
}
/* DSD */
if (config->probed || config->property_count || config->compat_string ||
(reset_gpio_index != -1) ||
(enable_gpio_index != -1) || (irq_gpio_index != -1)) {
dsd = acpi_dp_new_table("_DSD");
if (config->compat_string)
acpi_dp_add_string(dsd, "compatible",
config->compat_string);
if (config->probed)
acpi_dp_add_integer(dsd, "linux,probed", 1);
if (irq_gpio_index != -1)
acpi_dp_add_gpio(dsd, "irq-gpios", path,
irq_gpio_index, 0,
config->irq_gpio.active_low);
if (reset_gpio_index != -1)
acpi_dp_add_gpio(dsd, "reset-gpios", path,
reset_gpio_index, 0,
config->reset_gpio.active_low);
if (enable_gpio_index != -1)
acpi_dp_add_gpio(dsd, "enable-gpios", path,
enable_gpio_index, 0,
config->enable_gpio.active_low);
/* Add generic property list */
acpi_dp_add_property_list(dsd, config->property_list,
config->property_count);
acpi_dp_write(dsd);
}
/* Power Resource */
if (config->has_power_resource) {
const struct acpi_power_res_params power_res_params = {
&config->reset_gpio,
config->reset_delay_ms,
config->reset_off_delay_ms,
&config->enable_gpio,
config->enable_delay_ms,
config->enable_off_delay_ms,
&config->stop_gpio,
config->stop_delay_ms,
config->stop_off_delay_ms
};
acpi_device_add_power_res(&power_res_params);
}
/* Callback if any. */
if (callback)
callback(dev);
acpigen_pop_len(); /* Device */
acpigen_pop_len(); /* Scope */
printk(BIOS_INFO, "%s: %s at %s\n", path,
config->desc ? : dev->chip_ops->name, dev_path(dev));
}
static void i2c_generic_fill_ssdt_generator(const struct device *dev)
{
i2c_generic_fill_ssdt(dev, NULL, dev->chip_info);
}
/* Use name specified in config or build one from I2C address */
static const char *i2c_generic_acpi_name(const struct device *dev)
{
struct drivers_i2c_generic_config *config = dev->chip_info;
static char name[5];
if (config->name)
return config->name;
snprintf(name, sizeof(name), "D%03.3X", dev->path.i2c.device);
name[4] = '\0';
return name;
}
#endif
static struct device_operations i2c_generic_ops = {
.read_resources = noop_read_resources,
.set_resources = noop_set_resources,
#if CONFIG(HAVE_ACPI_TABLES)
.acpi_name = i2c_generic_acpi_name,
.acpi_fill_ssdt = i2c_generic_fill_ssdt_generator,
#endif
};
static void i2c_generic_enable(struct device *dev)
{
struct drivers_i2c_generic_config *config = dev->chip_info;
if (!config)
return;
/* Check if device is present by reading GPIO */
if (config->device_present_gpio) {
int present = gpio_get(config->device_present_gpio);
present ^= config->device_present_gpio_invert;
printk(BIOS_INFO, "%s is %spresent\n",
dev->chip_ops->name, present ? "" : "not ");
if (!present) {
dev->enabled = 0;
return;
}
}
dev->ops = &i2c_generic_ops;
/* Name the device as per description provided in devicetree */
if (config->desc)
dev->name = config->desc;
}
struct chip_operations drivers_i2c_generic_ops = {
CHIP_NAME("I2C Device")
.enable_dev = i2c_generic_enable
};
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