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/of_platform.h>
 12#include <linux/platform_device.h>
 13#include <linux/slab.h>
 14
 15static const char * const adsp_mbox_ch_names[MTK_ADSP_MBOX_NUM] = { "rx", "tx" };
 16
 17/*
 18 * mtk_adsp_ipc_send - send ipc cmd to MTK ADSP
 19 *
 20 * @ipc: ADSP IPC handle
 21 * @idx: index of the mailbox channel
 22 * @msg: IPC cmd (reply or request)
 23 *
 24 * Returns zero for success from mbox_send_message
 25 * negative value for error
 26 */
 27int mtk_adsp_ipc_send(struct mtk_adsp_ipc *ipc, unsigned int idx, uint32_t msg)
 28{
 29	struct mtk_adsp_chan *adsp_chan;
 30	int ret;
 31
 32	if (idx >= MTK_ADSP_MBOX_NUM)
 33		return -EINVAL;
 34
 35	adsp_chan = &ipc->chans[idx];
 36	ret = mbox_send_message(adsp_chan->ch, &msg);
 37	if (ret < 0)
 38		return ret;
 39
 40	return 0;
 41}
 42EXPORT_SYMBOL_GPL(mtk_adsp_ipc_send);
 43
 44/*
 45 * mtk_adsp_ipc_recv - recv callback used by MTK ADSP mailbox
 46 *
 47 * @c: mbox client
 48 * @msg: message received
 49 *
 50 * Users of ADSP IPC will need to privde handle_reply and handle_request
 51 * callbacks.
 52 */
 53static void mtk_adsp_ipc_recv(struct mbox_client *c, void *msg)
 54{
 55	struct mtk_adsp_chan *chan = container_of(c, struct mtk_adsp_chan, cl);
 56	struct device *dev = c->dev;
 57
 58	switch (chan->idx) {
 59	case MTK_ADSP_MBOX_REPLY:
 60		chan->ipc->ops->handle_reply(chan->ipc);
 61		break;
 62	case MTK_ADSP_MBOX_REQUEST:
 63		chan->ipc->ops->handle_request(chan->ipc);
 64		break;
 65	default:
 66		dev_err(dev, "wrong mbox chan %d\n", chan->idx);
 67		break;
 68	}
 69}
 70
 71static int mtk_adsp_ipc_probe(struct platform_device *pdev)
 72{
 73	struct device *dev = &pdev->dev;
 74	struct mtk_adsp_ipc *adsp_ipc;
 75	struct mtk_adsp_chan *adsp_chan;
 76	struct mbox_client *cl;
 77	int ret;
 78	int i, j;
 79
 80	device_set_of_node_from_dev(&pdev->dev, pdev->dev.parent);
 81
 82	adsp_ipc = devm_kzalloc(dev, sizeof(*adsp_ipc), GFP_KERNEL);
 83	if (!adsp_ipc)
 84		return -ENOMEM;
 85
 86	for (i = 0; i < MTK_ADSP_MBOX_NUM; i++) {
 87		adsp_chan = &adsp_ipc->chans[i];
 88		cl = &adsp_chan->cl;
 89		cl->dev = dev->parent;
 90		cl->tx_block = false;
 91		cl->knows_txdone = false;
 92		cl->tx_prepare = NULL;
 93		cl->rx_callback = mtk_adsp_ipc_recv;
 94
 95		adsp_chan->ipc = adsp_ipc;
 96		adsp_chan->idx = i;
 97		adsp_chan->ch = mbox_request_channel_byname(cl, adsp_mbox_ch_names[i]);
 98		if (IS_ERR(adsp_chan->ch)) {
 99			ret = PTR_ERR(adsp_chan->ch);
100			if (ret != -EPROBE_DEFER)
101				dev_err(dev, "Failed to request mbox chan %s ret %d\n",
102					adsp_mbox_ch_names[i], ret);
103
104			for (j = 0; j < i; j++) {
105				adsp_chan = &adsp_ipc->chans[j];
106				mbox_free_channel(adsp_chan->ch);
107			}
108
109			return ret;
110		}
111	}
112
113	adsp_ipc->dev = dev;
114	dev_set_drvdata(dev, adsp_ipc);
115	dev_dbg(dev, "MTK ADSP IPC initialized\n");
116
117	return 0;
118}
119
120static int mtk_adsp_ipc_remove(struct platform_device *pdev)
121{
122	struct mtk_adsp_ipc *adsp_ipc = dev_get_drvdata(&pdev->dev);
123	struct mtk_adsp_chan *adsp_chan;
124	int i;
125
126	for (i = 0; i < MTK_ADSP_MBOX_NUM; i++) {
127		adsp_chan = &adsp_ipc->chans[i];
128		mbox_free_channel(adsp_chan->ch);
129	}
130
131	return 0;
132}
133
134static struct platform_driver mtk_adsp_ipc_driver = {
135	.driver = {
136		.name = "mtk-adsp-ipc",
137	},
138	.probe = mtk_adsp_ipc_probe,
139	.remove = mtk_adsp_ipc_remove,
140};
141builtin_platform_driver(mtk_adsp_ipc_driver);
142
143MODULE_AUTHOR("Allen-KH Cheng <allen-kh.cheng@mediatek.com>");
144MODULE_DESCRIPTION("MTK ADSP IPC Driver");
145MODULE_LICENSE("GPL");