| /* |
| * This file is part of the coreboot project. |
| * |
| * Copyright 2016 Google Inc. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; version 2 of the License. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #include <arch/acpi_device.h> |
| #include <arch/acpigen.h> |
| #include <console/console.h> |
| #include <device/i2c.h> |
| #include <device/device.h> |
| #include <device/path.h> |
| #include <gpio.h> |
| #include <stdint.h> |
| #include <string.h> |
| #include "chip.h" |
| |
| #if IS_ENABLED(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(struct device *dev, |
| void (*callback)(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 (!dev->enabled || !scope) |
| return; |
| |
| if (!config->hid) { |
| printk(BIOS_ERR, "%s: ERROR: HID required\n", dev_path(dev)); |
| return; |
| } |
| |
| /* 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); |
| acpigen_write_name_string("_DDN", config->desc); |
| acpigen_write_STA(ACPI_STATUS_DEVICE_ALL_ON); |
| |
| /* 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", 4); |
| acpigen_write_PRW(config->wake, 3); |
| } |
| |
| /* DSD */ |
| if (config->probed || (reset_gpio_index != -1) || |
| (enable_gpio_index != -1) || (irq_gpio_index != -1)) { |
| dsd = acpi_dp_new_table("_DSD"); |
| 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.polarity == |
| ACPI_GPIO_ACTIVE_LOW); |
| if (reset_gpio_index != -1) |
| acpi_dp_add_gpio(dsd, "reset-gpios", path, |
| reset_gpio_index, 0, |
| config->reset_gpio.polarity); |
| if (enable_gpio_index != -1) |
| 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) |
| acpi_device_add_power_res( |
| &config->reset_gpio, config->reset_delay_ms, |
| &config->enable_gpio, config->enable_delay_ms); |
| |
| /* 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(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(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 = DEVICE_NOOP, |
| .set_resources = DEVICE_NOOP, |
| .enable_resources = DEVICE_NOOP, |
| #if IS_ENABLED(CONFIG_HAVE_ACPI_TABLES) |
| .acpi_name = &i2c_generic_acpi_name, |
| .acpi_fill_ssdt_generator = &i2c_generic_fill_ssdt_generator, |
| #endif |
| }; |
| |
| static void i2c_generic_enable(struct device *dev) |
| { |
| struct drivers_i2c_generic_config *config = dev->chip_info; |
| |
| /* 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; |
| } |
| |
| struct chip_operations drivers_i2c_generic_ops = { |
| CHIP_NAME("I2C Device") |
| .enable_dev = &i2c_generic_enable |
| }; |