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Diffstat (limited to 'src/drivers/i2c/generic/generic.c')
-rw-r--r--src/drivers/i2c/generic/generic.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/src/drivers/i2c/generic/generic.c b/src/drivers/i2c/generic/generic.c
new file mode 100644
index 0000000000..1c10b0e3cf
--- /dev/null
+++ b/src/drivers/i2c/generic/generic.c
@@ -0,0 +1,124 @@
+/*
+ * 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 void i2c_generic_fill_ssdt(struct device *dev)
+{
+ struct drivers_i2c_generic_config *config = dev->chip_info;
+ 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->bus_speed ? : I2C_SPEED_FAST,
+ .resource = scope,
+ };
+
+ 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);
+ 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);
+ acpi_device_write_interrupt(&config->irq);
+ acpigen_write_resourcetemplate_footer();
+
+ /* Wake capabilities */
+ if (config->wake) {
+ acpigen_write_name_integer("_S0W", 4);
+ acpigen_write_PRW(config->wake, 3);
+ }
+
+ acpigen_pop_len(); /* Device */
+ acpigen_pop_len(); /* Scope */
+
+ printk(BIOS_INFO, "%s: %s at %s\n", acpi_device_path(dev),
+ config->desc ? : dev->chip_ops->name, dev_path(dev));
+}
+
+/* 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 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,
+#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
+};