xref: /linux/sound/soc/sof/sof-client-ipc-msg-injector.c (revision ed85a6e6fe7c01faff4504af9d5569e8ba417999)
1 // SPDX-License-Identifier: GPL-2.0-only
2 //
3 // Copyright(c) 2022 Intel Corporation. All rights reserved.
4 //
5 // Author: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
6 //
7 
8 #include <linux/auxiliary_bus.h>
9 #include <linux/completion.h>
10 #include <linux/debugfs.h>
11 #include <linux/ktime.h>
12 #include <linux/mod_devicetable.h>
13 #include <linux/module.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/slab.h>
16 #include <linux/uaccess.h>
17 #include <sound/sof/header.h>
18 
19 #include "sof-client.h"
20 
21 #define SOF_IPC_CLIENT_SUSPEND_DELAY_MS	3000
22 
23 struct sof_msg_inject_priv {
24 	struct dentry *dfs_file;
25 
26 	void *tx_buffer;
27 	void *rx_buffer;
28 };
29 
30 static int sof_msg_inject_dfs_open(struct inode *inode, struct file *file)
31 {
32 	struct sof_client_dev *cdev = inode->i_private;
33 	int ret;
34 
35 	if (sof_client_get_fw_state(cdev) == SOF_FW_CRASHED)
36 		return -ENODEV;
37 
38 	ret = debugfs_file_get(file->f_path.dentry);
39 	if (unlikely(ret))
40 		return ret;
41 
42 	ret = simple_open(inode, file);
43 	if (ret)
44 		debugfs_file_put(file->f_path.dentry);
45 
46 	return ret;
47 }
48 
49 static ssize_t sof_msg_inject_dfs_read(struct file *file, char __user *buffer,
50 				       size_t count, loff_t *ppos)
51 {
52 	struct sof_client_dev *cdev = file->private_data;
53 	struct sof_msg_inject_priv *priv = cdev->data;
54 	struct sof_ipc_reply *rhdr = priv->rx_buffer;
55 
56 	if (!rhdr->hdr.size || !count || *ppos)
57 		return 0;
58 
59 	if (count > rhdr->hdr.size)
60 		count = rhdr->hdr.size;
61 
62 	if (copy_to_user(buffer, priv->rx_buffer, count))
63 		return -EFAULT;
64 
65 	*ppos += count;
66 	return count;
67 }
68 
69 static ssize_t sof_msg_inject_dfs_write(struct file *file, const char __user *buffer,
70 					size_t count, loff_t *ppos)
71 {
72 	struct sof_client_dev *cdev = file->private_data;
73 	struct sof_msg_inject_priv *priv = cdev->data;
74 	struct device *dev = &cdev->auxdev.dev;
75 	int ret, err;
76 	size_t size;
77 
78 	if (*ppos)
79 		return 0;
80 
81 	size = simple_write_to_buffer(priv->tx_buffer, SOF_IPC_MSG_MAX_SIZE,
82 				      ppos, buffer, count);
83 	if (size != count)
84 		return size > 0 ? -EFAULT : size;
85 
86 	ret = pm_runtime_resume_and_get(dev);
87 	if (ret < 0 && ret != -EACCES) {
88 		dev_err_ratelimited(dev, "debugfs write failed to resume %d\n", ret);
89 		return ret;
90 	}
91 
92 	/* send the message */
93 	memset(priv->rx_buffer, 0, SOF_IPC_MSG_MAX_SIZE);
94 	ret = sof_client_ipc_tx_message(cdev, priv->tx_buffer, priv->rx_buffer,
95 					SOF_IPC_MSG_MAX_SIZE);
96 	pm_runtime_mark_last_busy(dev);
97 	err = pm_runtime_put_autosuspend(dev);
98 	if (err < 0)
99 		dev_err_ratelimited(dev, "debugfs write failed to idle %d\n", err);
100 
101 	/* return size if test is successful */
102 	if (ret >= 0)
103 		ret = size;
104 
105 	return ret;
106 };
107 
108 static int sof_msg_inject_dfs_release(struct inode *inode, struct file *file)
109 {
110 	debugfs_file_put(file->f_path.dentry);
111 
112 	return 0;
113 }
114 
115 static const struct file_operations sof_msg_inject_fops = {
116 	.open = sof_msg_inject_dfs_open,
117 	.read = sof_msg_inject_dfs_read,
118 	.write = sof_msg_inject_dfs_write,
119 	.llseek = default_llseek,
120 	.release = sof_msg_inject_dfs_release,
121 
122 	.owner = THIS_MODULE,
123 };
124 
125 static int sof_msg_inject_probe(struct auxiliary_device *auxdev,
126 				const struct auxiliary_device_id *id)
127 {
128 	struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
129 	struct dentry *debugfs_root = sof_client_get_debugfs_root(cdev);
130 	struct device *dev = &auxdev->dev;
131 	struct sof_msg_inject_priv *priv;
132 
133 	/* allocate memory for client data */
134 	priv = devm_kzalloc(&auxdev->dev, sizeof(*priv), GFP_KERNEL);
135 	if (!priv)
136 		return -ENOMEM;
137 
138 	priv->tx_buffer = devm_kmalloc(dev, SOF_IPC_MSG_MAX_SIZE, GFP_KERNEL);
139 	priv->rx_buffer = devm_kzalloc(dev, SOF_IPC_MSG_MAX_SIZE, GFP_KERNEL);
140 	if (!priv->tx_buffer || !priv->rx_buffer)
141 		return -ENOMEM;
142 
143 	cdev->data = priv;
144 
145 	priv->dfs_file = debugfs_create_file("ipc_msg_inject", 0644, debugfs_root,
146 					     cdev, &sof_msg_inject_fops);
147 
148 	/* enable runtime PM */
149 	pm_runtime_set_autosuspend_delay(dev, SOF_IPC_CLIENT_SUSPEND_DELAY_MS);
150 	pm_runtime_use_autosuspend(dev);
151 	pm_runtime_enable(dev);
152 	pm_runtime_mark_last_busy(dev);
153 	pm_runtime_idle(dev);
154 
155 	return 0;
156 }
157 
158 static void sof_msg_inject_remove(struct auxiliary_device *auxdev)
159 {
160 	struct sof_client_dev *cdev = auxiliary_dev_to_sof_client_dev(auxdev);
161 	struct sof_msg_inject_priv *priv = cdev->data;
162 
163 	pm_runtime_disable(&auxdev->dev);
164 
165 	debugfs_remove(priv->dfs_file);
166 }
167 
168 static const struct auxiliary_device_id sof_msg_inject_client_id_table[] = {
169 	{ .name = "snd_sof.msg_injector" },
170 	{},
171 };
172 MODULE_DEVICE_TABLE(auxiliary, sof_msg_inject_client_id_table);
173 
174 /*
175  * No need for driver pm_ops as the generic pm callbacks in the auxiliary bus
176  * type are enough to ensure that the parent SOF device resumes to bring the DSP
177  * back to D0.
178  * Driver name will be set based on KBUILD_MODNAME.
179  */
180 static struct auxiliary_driver sof_msg_inject_client_drv = {
181 	.probe = sof_msg_inject_probe,
182 	.remove = sof_msg_inject_remove,
183 
184 	.id_table = sof_msg_inject_client_id_table,
185 };
186 
187 module_auxiliary_driver(sof_msg_inject_client_drv);
188 
189 MODULE_DESCRIPTION("SOF IPC Message Injector Client Driver");
190 MODULE_LICENSE("GPL");
191 MODULE_IMPORT_NS(SND_SOC_SOF_CLIENT);
192