| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| |
| #include <acpi/acpi_device.h> |
| #include <acpi/acpigen.h> |
| #include <console/console.h> |
| #include <device/path.h> |
| #include <string.h> |
| #include "chip.h" |
| |
| static bool uart_acpi_add_gpios_to_crs(struct drivers_uart_acpi_config *config) |
| { |
| /* |
| * Return false if: |
| * 1. Request to explicitly disable export of GPIOs in CRS, or |
| * 2. Both reset and enable GPIOs are not provided. |
| */ |
| if (config->disable_gpio_export_in_crs || |
| ((config->reset_gpio.pin_count == 0) && |
| (config->enable_gpio.pin_count == 0))) |
| return false; |
| |
| return true; |
| } |
| |
| static int uart_acpi_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; |
| } |
| |
| static void uart_acpi_fill_ssdt(const struct device *dev) |
| { |
| const char *scope = acpi_device_scope(dev); |
| const char *path = acpi_device_path(dev); |
| struct drivers_uart_acpi_config *config = dev->chip_info; |
| int curr_index = 0; |
| int irq_gpio_index = -1; |
| int reset_gpio_index = -1; |
| int enable_gpio_index = -1; |
| |
| if (!dev->enabled || !scope) |
| return; |
| |
| if (!config->hid) { |
| printk(BIOS_ERR, "%s: ERROR: HID required\n", dev_path(dev)); |
| return; |
| } |
| |
| 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); |
| acpigen_write_name_string("_DDN", config->desc); |
| acpigen_write_STA(acpi_device_status(dev)); |
| |
| /* Resources */ |
| acpigen_write_name("_CRS"); |
| acpigen_write_resourcetemplate_header(); |
| |
| /* Fix up resource pointer to this scope */ |
| config->uart.resource = scope; |
| acpi_device_write_uart(&config->uart); |
| |
| /* Use either Interrupt() or GpioInt() */ |
| if (config->irq_gpio.pin_count) |
| acpi_device_write_gpio(&config->irq_gpio); |
| else |
| acpi_device_write_interrupt(&config->irq); |
| |
| /* Add enable/reset GPIOs if needed */ |
| if (uart_acpi_add_gpios_to_crs(config)) { |
| reset_gpio_index = uart_acpi_write_gpio(&config->reset_gpio, |
| &curr_index); |
| enable_gpio_index = uart_acpi_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_COLD); |
| acpigen_write_PRW(config->wake, SLP_TYP_S3); |
| }; |
| |
| /* Write device properties if needed */ |
| if (config->compat_string || irq_gpio_index >= 0 || |
| reset_gpio_index >= 0 || enable_gpio_index >= 0) { |
| struct acpi_dp *dsd = acpi_dp_new_table("_DSD"); |
| if (config->compat_string) |
| acpi_dp_add_string(dsd, "compatible", |
| config->compat_string); |
| if (irq_gpio_index >= 0) |
| acpi_dp_add_gpio(dsd, "irq-gpios", path, |
| irq_gpio_index, 0, |
| config->irq_gpio.polarity); |
| if (reset_gpio_index >= 0) |
| acpi_dp_add_gpio(dsd, "reset-gpios", path, |
| reset_gpio_index, 0, |
| config->reset_gpio.polarity); |
| if (enable_gpio_index >= 0) |
| acpi_dp_add_gpio(dsd, "enable-gpios", path, |
| enable_gpio_index, 0, |
| config->enable_gpio.polarity); |
| 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); |
| } |
| |
| acpigen_pop_len(); /* Device */ |
| acpigen_pop_len(); /* Scope */ |
| |
| printk(BIOS_INFO, "%s: %s at %s\n", path, config->desc, dev_path(dev)); |
| } |
| |
| static const char *uart_acpi_name(const struct device *dev) |
| { |
| struct drivers_uart_acpi_config *config = dev->chip_info; |
| static char name[5]; |
| |
| if (config->name) |
| return config->name; |
| |
| snprintf(name, sizeof(name), "D%03.3X", dev->path.generic.id); |
| return name; |
| } |
| |
| static struct device_operations uart_acpi_dev_ops = { |
| .read_resources = noop_read_resources, |
| .set_resources = noop_set_resources, |
| .acpi_fill_ssdt = uart_acpi_fill_ssdt, |
| .acpi_name = uart_acpi_name, |
| }; |
| |
| static void uart_acpi_enable(struct device *dev) |
| { |
| struct drivers_uart_acpi_config *config = dev->chip_info; |
| |
| if (config->desc) |
| dev->name = config->desc; |
| else |
| config->desc = dev->chip_ops->name; |
| |
| dev->ops = &uart_acpi_dev_ops; |
| } |
| |
| struct chip_operations drivers_uart_acpi_ops = { |
| CHIP_NAME("ACPI UART Device") |
| .enable_dev = uart_acpi_enable |
| }; |