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1// SPDX-License-Identifier: GPL-2.0-only2//3// Copyright(c) 2023 Google Inc4//5// Author: Curtis Malainey <cujomalainey@chromium.org>6//7 8#include <linux/auxiliary_bus.h>9#include <linux/debugfs.h>10#include <linux/mod_devicetable.h>11#include <linux/module.h>12#include <linux/pm_runtime.h>13#include <sound/sof/header.h>14 15#include "sof-client.h"16 17#define SOF_IPC_CLIENT_SUSPEND_DELAY_MS 300018 19struct sof_msg_inject_priv {20 struct dentry *kernel_dfs_file;21 size_t max_msg_size;22 23 void *kernel_buffer;24};25 26static int sof_msg_inject_dfs_open(struct inode *inode, struct file *file)27{28 int ret = debugfs_file_get(file->f_path.dentry);29 30 if (unlikely(ret))31 return ret;32 33 ret = simple_open(inode, file);34 if (ret)35 debugfs_file_put(file->f_path.dentry);36 37 return ret;38}39 40static ssize_t sof_kernel_msg_inject_dfs_write(struct file *file, const char __user *buffer,41 size_t count, loff_t *ppos)42{43 struct sof_client_dev *cdev = file->private_data;44 struct sof_msg_inject_priv *priv = cdev->data;45 struct sof_ipc_cmd_hdr *hdr = priv->kernel_buffer;46 struct device *dev = &cdev->auxdev.dev;47 ssize_t size;48 int ret;49 50 if (*ppos)51 return 0;52 53 size = simple_write_to_buffer(priv->kernel_buffer, priv->max_msg_size,54 ppos, buffer, count);55 if (size < 0)56 return size;57 if (size != count)58 return -EFAULT;59 60 ret = pm_runtime_resume_and_get(dev);61 if (ret < 0 && ret != -EACCES) {62 dev_err_ratelimited(dev, "debugfs write failed to resume %d\n", ret);63 return ret;64 }65 66 sof_client_ipc_rx_message(cdev, hdr, priv->kernel_buffer);67 68 pm_runtime_mark_last_busy(dev);69 ret = pm_runtime_put_autosuspend(dev);70 if (ret < 0)71 dev_err_ratelimited(dev, "debugfs write failed to idle %d\n", ret);72 73 return count;74};75 76static int sof_msg_inject_dfs_release(struct inode *inode, struct file *file)77{78 debugfs_file_put(file->f_path.dentry);79 80 return 0;81}82 83static const struct file_operations sof_kernel_msg_inject_fops = {84 .open = sof_msg_inject_dfs_open,85 .write = sof_kernel_msg_inject_dfs_write,86 .release = sof_msg_inject_dfs_release,87 88 .owner = THIS_MODULE,89};90 91static int sof_msg_inject_probe(struct auxiliary_device *auxdev,92 const struct auxiliary_device_id *id)93{94 struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);95 struct dentry *debugfs_root = sof_client_get_debugfs_root(cdev);96 struct device *dev = &auxdev->dev;97 struct sof_msg_inject_priv *priv;98 size_t alloc_size;99 100 /* allocate memory for client data */101 priv = devm_kzalloc(&auxdev->dev, sizeof(*priv), GFP_KERNEL);102 if (!priv)103 return -ENOMEM;104 105 priv->max_msg_size = sof_client_get_ipc_max_payload_size(cdev);106 alloc_size = priv->max_msg_size;107 priv->kernel_buffer = devm_kmalloc(dev, alloc_size, GFP_KERNEL);108 109 if (!priv->kernel_buffer)110 return -ENOMEM;111 112 cdev->data = priv;113 114 priv->kernel_dfs_file = debugfs_create_file("kernel_ipc_msg_inject", 0644,115 debugfs_root, cdev,116 &sof_kernel_msg_inject_fops);117 118 /* enable runtime PM */119 pm_runtime_set_autosuspend_delay(dev, SOF_IPC_CLIENT_SUSPEND_DELAY_MS);120 pm_runtime_use_autosuspend(dev);121 pm_runtime_set_active(dev);122 pm_runtime_enable(dev);123 pm_runtime_mark_last_busy(dev);124 pm_runtime_idle(dev);125 126 return 0;127}128 129static void sof_msg_inject_remove(struct auxiliary_device *auxdev)130{131 struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);132 struct sof_msg_inject_priv *priv = cdev->data;133 134 pm_runtime_disable(&auxdev->dev);135 136 debugfs_remove(priv->kernel_dfs_file);137}138 139static const struct auxiliary_device_id sof_msg_inject_client_id_table[] = {140 { .name = "snd_sof.kernel_injector" },141 {},142};143MODULE_DEVICE_TABLE(auxiliary, sof_msg_inject_client_id_table);144 145/*146 * No need for driver pm_ops as the generic pm callbacks in the auxiliary bus147 * type are enough to ensure that the parent SOF device resumes to bring the DSP148 * back to D0.149 * Driver name will be set based on KBUILD_MODNAME.150 */151static struct auxiliary_driver sof_msg_inject_client_drv = {152 .probe = sof_msg_inject_probe,153 .remove = sof_msg_inject_remove,154 155 .id_table = sof_msg_inject_client_id_table,156};157 158module_auxiliary_driver(sof_msg_inject_client_drv);159 160MODULE_LICENSE("GPL");161MODULE_DESCRIPTION("SOF IPC Kernel Injector Client Driver");162MODULE_IMPORT_NS(SND_SOC_SOF_CLIENT);163