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(adsp_chan->ch, &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(&pdev->dev, pdev->dev.parent);
 80
 81	adsp_ipc = devm_kzalloc(dev, 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, adsp_mbox_ch_names[i]);
 97		if (IS_ERR(adsp_chan->ch)) {
 98			ret = PTR_ERR(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(adsp_chan->ch);
106			}
107
108			return ret;
109		}
110	}
111
112	adsp_ipc->dev = dev;
113	dev_set_drvdata(dev, 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(&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(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");