1 // SPDX-License-Identifier: GPL-2.0
3  * System Control and Management Interface (SCMI) Message Mailbox Transport
19  * struct scmi_mailbox - Structure representing a SCMI mailbox transport
22  * @chan: Transmit/Receive mailbox uni/bi-directional channel
43 	shmem_tx_prepare(smbox->shmem, m, smbox->cinfo);  in tx_prepare()
56 	 * a previous timed-out reply which arrived late could be wrongly  in rx_callback()
59 	if (cl->knows_txdone && !shmem_channel_free(smbox->shmem)) {  in rx_callback()
60 		dev_warn(smbox->cinfo->dev, "Ignoring spurious A2P IRQ !\n");  in rx_callback()
64 	scmi_rx_callback(smbox->cinfo, shmem_read_header(smbox->shmem), NULL);  in rx_callback()
76 	num_mb = of_count_phandle_with_args(of_node, "mboxes", "#mbox-cells");  in mailbox_chan_available()
81 					   "#mbox-cells", idx, NULL);  in mailbox_chan_available()
85  * mailbox_chan_validate  - Validate transport configuration and map channels
91  * @p2a_chan: A reference to the optional p2a channel.
104 	struct device_node *np = cdev->of_node;  in mailbox_chan_validate()
106 	num_mb = of_count_phandle_with_args(np, "mboxes", "#mbox-cells");  in mailbox_chan_validate()
114 			 "Invalid channel descriptor for '%s' - mbs:%d  shm:%d\n",  in mailbox_chan_validate()
116 		return -EINVAL;  in mailbox_chan_validate()
128 			ret = -EINVAL;  in mailbox_chan_validate()
165 	struct device *cdev = cinfo->dev;  in mailbox_chan_setup()
178 		return -ENODEV;  in mailbox_chan_setup()
182 		return -ENOMEM;  in mailbox_chan_setup()
184 	shmem = of_parse_phandle(cdev->of_node, "shmem", idx);  in mailbox_chan_setup()
185 	if (!of_device_is_compatible(shmem, "arm,scmi-shmem")) {  in mailbox_chan_setup()
187 		return -ENXIO;  in mailbox_chan_setup()
198 	smbox->shmem = devm_ioremap(dev, res.start, size);  in mailbox_chan_setup()
199 	if (!smbox->shmem) {  in mailbox_chan_setup()
201 		return -EADDRNOTAVAIL;  in mailbox_chan_setup()
204 	cl = &smbox->cl;  in mailbox_chan_setup()
205 	cl->dev = cdev;  in mailbox_chan_setup()
206 	cl->tx_prepare = tx ? tx_prepare : NULL;  in mailbox_chan_setup()
207 	cl->rx_callback = rx_callback;  in mailbox_chan_setup()
208 	cl->tx_block = false;  in mailbox_chan_setup()
209 	cl->knows_txdone = tx;  in mailbox_chan_setup()
211 	smbox->chan = mbox_request_channel(cl, tx ? 0 : p2a_chan);  in mailbox_chan_setup()
212 	if (IS_ERR(smbox->chan)) {  in mailbox_chan_setup()
213 		ret = PTR_ERR(smbox->chan);  in mailbox_chan_setup()
214 		if (ret != -EPROBE_DEFER)  in mailbox_chan_setup()
222 		smbox->chan_receiver = mbox_request_channel(cl, a2p_rx_chan);  in mailbox_chan_setup()
223 		if (IS_ERR(smbox->chan_receiver)) {  in mailbox_chan_setup()
224 			ret = PTR_ERR(smbox->chan_receiver);  in mailbox_chan_setup()
225 			if (ret != -EPROBE_DEFER)  in mailbox_chan_setup()
231 	cinfo->transport_info = smbox;  in mailbox_chan_setup()
232 	smbox->cinfo = cinfo;  in mailbox_chan_setup()
233 	mutex_init(&smbox->chan_lock);  in mailbox_chan_setup()
241 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_chan_free()
243 	if (smbox && !IS_ERR(smbox->chan)) {  in mailbox_chan_free()
244 		mbox_free_channel(smbox->chan);  in mailbox_chan_free()
245 		mbox_free_channel(smbox->chan_receiver);  in mailbox_chan_free()
246 		cinfo->transport_info = NULL;  in mailbox_chan_free()
247 		smbox->chan = NULL;  in mailbox_chan_free()
248 		smbox->chan_receiver = NULL;  in mailbox_chan_free()
249 		smbox->cinfo = NULL;  in mailbox_chan_free()
258 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_send_message()
268 	mutex_lock(&smbox->chan_lock);  in mailbox_send_message()
270 	ret = mbox_send_message(smbox->chan, xfer);  in mailbox_send_message()
271 	/* mbox_send_message returns non-negative value on success */  in mailbox_send_message()
273 		mutex_unlock(&smbox->chan_lock);  in mailbox_send_message()
283 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_mark_txdone()
285 	mbox_client_txdone(smbox->chan, ret);  in mailbox_mark_txdone()
288 	mutex_unlock(&smbox->chan_lock);  in mailbox_mark_txdone()
294 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_fetch_response()
296 	shmem_fetch_response(smbox->shmem, xfer);  in mailbox_fetch_response()
302 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_fetch_notification()
304 	shmem_fetch_notification(smbox->shmem, max_len, xfer);  in mailbox_fetch_notification()
309 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_clear_channel()
311 	shmem_clear_channel(smbox->shmem);  in mailbox_clear_channel()
317 	struct scmi_mailbox *smbox = cinfo->transport_info;  in mailbox_poll_done()
319 	return shmem_poll_done(smbox->shmem, xfer);  in mailbox_poll_done()