1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (c) 2022 MediaTek Corporation. All rights reserved.
4 * Author: Allen-KH Cheng <allen-kh.cheng@mediatek.com>
5 */
6
7#include <linux/firmware/mediatek/mtk-adsp-ipc.h>
8#include <linux/kernel.h>
9#include <linux/mailbox_client.h>
10#include <linux/module.h>
11#include <linux/platform_device.h>
12#include <linux/slab.h>
13
14static const char * const adsp_mbox_ch_names[MTK_ADSP_MBOX_NUM] = { "rx", "tx" };
15
16/*
17 * mtk_adsp_ipc_send - send ipc cmd to MTK ADSP
18 *
19 * @ipc: ADSP IPC handle
20 * @idx: index of the mailbox channel
21 * @msg: IPC cmd (reply or request)
22 *
23 * Returns zero for success from mbox_send_message
24 * negative value for error
25 */
26int mtk_adsp_ipc_send(struct mtk_adsp_ipc *ipc, unsigned int idx, uint32_t msg)
27{
28 struct mtk_adsp_chan *adsp_chan;
29 int ret;
30
31 if (idx >= MTK_ADSP_MBOX_NUM)
32 return -EINVAL;
33
34 adsp_chan = &ipc->chans[idx];
35 ret = mbox_send_message(chan: adsp_chan->ch, mssg: &msg);
36 if (ret < 0)
37 return ret;
38
39 return 0;
40}
41EXPORT_SYMBOL_GPL(mtk_adsp_ipc_send);
42
43/*
44 * mtk_adsp_ipc_recv - recv callback used by MTK ADSP mailbox
45 *
46 * @c: mbox client
47 * @msg: message received
48 *
49 * Users of ADSP IPC will need to privde handle_reply and handle_request
50 * callbacks.
51 */
52static void mtk_adsp_ipc_recv(struct mbox_client *c, void *msg)
53{
54 struct mtk_adsp_chan *chan = container_of(c, struct mtk_adsp_chan, cl);
55 struct device *dev = c->dev;
56
57 switch (chan->idx) {
58 case MTK_ADSP_MBOX_REPLY:
59 chan->ipc->ops->handle_reply(chan->ipc);
60 break;
61 case MTK_ADSP_MBOX_REQUEST:
62 chan->ipc->ops->handle_request(chan->ipc);
63 break;
64 default:
65 dev_err(dev, "wrong mbox chan %d\n", chan->idx);
66 break;
67 }
68}
69
70static int mtk_adsp_ipc_probe(struct platform_device *pdev)
71{
72 struct device *dev = &pdev->dev;
73 struct mtk_adsp_ipc *adsp_ipc;
74 struct mtk_adsp_chan *adsp_chan;
75 struct mbox_client *cl;
76 int ret;
77 int i, j;
78
79 device_set_of_node_from_dev(dev: &pdev->dev, dev2: pdev->dev.parent);
80
81 adsp_ipc = devm_kzalloc(dev, size: sizeof(*adsp_ipc), GFP_KERNEL);
82 if (!adsp_ipc)
83 return -ENOMEM;
84
85 for (i = 0; i < MTK_ADSP_MBOX_NUM; i++) {
86 adsp_chan = &adsp_ipc->chans[i];
87 cl = &adsp_chan->cl;
88 cl->dev = dev->parent;
89 cl->tx_block = false;
90 cl->knows_txdone = false;
91 cl->tx_prepare = NULL;
92 cl->rx_callback = mtk_adsp_ipc_recv;
93
94 adsp_chan->ipc = adsp_ipc;
95 adsp_chan->idx = i;
96 adsp_chan->ch = mbox_request_channel_byname(cl, name: adsp_mbox_ch_names[i]);
97 if (IS_ERR(ptr: adsp_chan->ch)) {
98 ret = PTR_ERR(ptr: adsp_chan->ch);
99 if (ret != -EPROBE_DEFER)
100 dev_err(dev, "Failed to request mbox chan %s ret %d\n",
101 adsp_mbox_ch_names[i], ret);
102
103 for (j = 0; j < i; j++) {
104 adsp_chan = &adsp_ipc->chans[j];
105 mbox_free_channel(chan: adsp_chan->ch);
106 }
107
108 return ret;
109 }
110 }
111
112 adsp_ipc->dev = dev;
113 dev_set_drvdata(dev, data: adsp_ipc);
114 dev_dbg(dev, "MTK ADSP IPC initialized\n");
115
116 return 0;
117}
118
119static void mtk_adsp_ipc_remove(struct platform_device *pdev)
120{
121 struct mtk_adsp_ipc *adsp_ipc = dev_get_drvdata(dev: &pdev->dev);
122 struct mtk_adsp_chan *adsp_chan;
123 int i;
124
125 for (i = 0; i < MTK_ADSP_MBOX_NUM; i++) {
126 adsp_chan = &adsp_ipc->chans[i];
127 mbox_free_channel(chan: adsp_chan->ch);
128 }
129}
130
131static struct platform_driver mtk_adsp_ipc_driver = {
132 .driver = {
133 .name = "mtk-adsp-ipc",
134 },
135 .probe = mtk_adsp_ipc_probe,
136 .remove_new = mtk_adsp_ipc_remove,
137};
138builtin_platform_driver(mtk_adsp_ipc_driver);
139
140MODULE_AUTHOR("Allen-KH Cheng <allen-kh.cheng@mediatek.com>");
141MODULE_DESCRIPTION("MTK ADSP IPC Driver");
142MODULE_LICENSE("GPL");
143

source code of linux/drivers/firmware/mtk-adsp-ipc.c