diff options
Diffstat (limited to 'drivers/firmware/qcom/qcom_qseecom.c')
-rw-r--r-- | drivers/firmware/qcom/qcom_qseecom.c | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/drivers/firmware/qcom/qcom_qseecom.c b/drivers/firmware/qcom/qcom_qseecom.c new file mode 100644 index 000000000000..731e6d5719f9 --- /dev/null +++ b/drivers/firmware/qcom/qcom_qseecom.c @@ -0,0 +1,120 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Driver for Qualcomm Secure Execution Environment (SEE) interface (QSEECOM). + * Responsible for setting up and managing QSEECOM client devices. + * + * Copyright (C) 2023 Maximilian Luz <luzmaximilian@gmail.com> + */ +#include <linux/auxiliary_bus.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/types.h> + +#include <linux/firmware/qcom/qcom_qseecom.h> +#include <linux/firmware/qcom/qcom_scm.h> + +struct qseecom_app_desc { + const char *app_name; + const char *dev_name; +}; + +static void qseecom_client_release(struct device *dev) +{ + struct qseecom_client *client; + + client = container_of(dev, struct qseecom_client, aux_dev.dev); + kfree(client); +} + +static void qseecom_client_remove(void *data) +{ + struct qseecom_client *client = data; + + auxiliary_device_delete(&client->aux_dev); + auxiliary_device_uninit(&client->aux_dev); +} + +static int qseecom_client_register(struct platform_device *qseecom_dev, + const struct qseecom_app_desc *desc) +{ + struct qseecom_client *client; + u32 app_id; + int ret; + + /* Try to find the app ID, skip device if not found */ + ret = qcom_scm_qseecom_app_get_id(desc->app_name, &app_id); + if (ret) + return ret == -ENOENT ? 0 : ret; + + dev_info(&qseecom_dev->dev, "setting up client for %s\n", desc->app_name); + + /* Allocate and set-up the client device */ + client = kzalloc(sizeof(*client), GFP_KERNEL); + if (!client) + return -ENOMEM; + + client->aux_dev.name = desc->dev_name; + client->aux_dev.dev.parent = &qseecom_dev->dev; + client->aux_dev.dev.release = qseecom_client_release; + client->app_id = app_id; + + ret = auxiliary_device_init(&client->aux_dev); + if (ret) { + kfree(client); + return ret; + } + + ret = auxiliary_device_add(&client->aux_dev); + if (ret) { + auxiliary_device_uninit(&client->aux_dev); + return ret; + } + + ret = devm_add_action_or_reset(&qseecom_dev->dev, qseecom_client_remove, client); + if (ret) + return ret; + + return 0; +} + +/* + * List of supported applications. One client device will be created per entry, + * assuming the app has already been loaded (usually by firmware bootloaders) + * and its ID can be queried successfully. + */ +static const struct qseecom_app_desc qcom_qseecom_apps[] = { + { "qcom.tz.uefisecapp", "uefisecapp" }, +}; + +static int qcom_qseecom_probe(struct platform_device *qseecom_dev) +{ + int ret; + int i; + + /* Set up client devices for each base application */ + for (i = 0; i < ARRAY_SIZE(qcom_qseecom_apps); i++) { + ret = qseecom_client_register(qseecom_dev, &qcom_qseecom_apps[i]); + if (ret) + return ret; + } + + return 0; +} + +static struct platform_driver qcom_qseecom_driver = { + .driver = { + .name = "qcom_qseecom", + }, + .probe = qcom_qseecom_probe, +}; + +static int __init qcom_qseecom_init(void) +{ + return platform_driver_register(&qcom_qseecom_driver); +} +subsys_initcall(qcom_qseecom_init); + +MODULE_AUTHOR("Maximilian Luz <luzmaximilian@gmail.com>"); +MODULE_DESCRIPTION("Driver for the Qualcomm SEE (QSEECOM) interface"); +MODULE_LICENSE("GPL"); |