1 // SPDX-License-Identifier: GPL-2.0
8  * This was inspired by Brendan Higgins' ipmi-bmc-bt-i2c driver.
34 #define IPMB_MSG_PAYLOAD_LEN_MAX (MAX_MSG_LEN - IPMB_REQUEST_LEN_MIN - 1)
71 	return container_of(file->private_data, struct ipmb_dev, miscdev);  in to_ipmb_dev()
84 	spin_lock_irq(&ipmb_dev->lock);  in ipmb_read()
86 	while (list_empty(&ipmb_dev->request_queue)) {  in ipmb_read()
87 		spin_unlock_irq(&ipmb_dev->lock);  in ipmb_read()
89 		if (file->f_flags & O_NONBLOCK)  in ipmb_read()
90 			return -EAGAIN;  in ipmb_read()
92 		ret = wait_event_interruptible(ipmb_dev->wait_queue,  in ipmb_read()
93 				!list_empty(&ipmb_dev->request_queue));  in ipmb_read()
97 		spin_lock_irq(&ipmb_dev->lock);  in ipmb_read()
100 	queue_elem = list_first_entry(&ipmb_dev->request_queue,  in ipmb_read()
102 	memcpy(&msg, &queue_elem->request, sizeof(msg));  in ipmb_read()
103 	list_del(&queue_elem->list);  in ipmb_read()
105 	atomic_dec(&ipmb_dev->request_queue_len);  in ipmb_read()
107 	spin_unlock_irq(&ipmb_dev->lock);  in ipmb_read()
111 		ret = -EFAULT;  in ipmb_read()
124 	i2c_msg.len = msg[IPMB_MSG_LEN_IDX] - 1;  in ipmb_i2c_write()
130 	i2c_msg.flags = client->flags & I2C_CLIENT_PEC;  in ipmb_i2c_write()
132 	return i2c_transfer(client->adapter, &i2c_msg, 1);  in ipmb_i2c_write()
145 		return -EINVAL;  in ipmb_write()
148 		return -EFAULT;  in ipmb_write()
151 		return -EINVAL;  in ipmb_write()
157 	if (ipmb_dev->is_i2c_protocol) {  in ipmb_write()
158 		ret = ipmb_i2c_write(ipmb_dev->client, msg, rq_sa);  in ipmb_write()
164 	 * temporary client. Note that its use is an exception for IPMI.  in ipmb_write()
166 	msg_len = msg[IPMB_MSG_LEN_IDX] - SMBUS_MSG_HEADER_LENGTH;  in ipmb_write()
167 	temp_client = kmemdup(ipmb_dev->client, sizeof(*temp_client), GFP_KERNEL);  in ipmb_write()
169 		return -ENOMEM;  in ipmb_write()
171 	temp_client->addr = rq_sa;  in ipmb_write()
185 	mutex_lock(&ipmb_dev->file_mutex);  in ipmb_poll()
186 	poll_wait(file, &ipmb_dev->wait_queue, wait);  in ipmb_poll()
188 	if (atomic_read(&ipmb_dev->request_queue_len))  in ipmb_poll()
190 	mutex_unlock(&ipmb_dev->file_mutex);  in ipmb_poll()
202 /* Called with ipmb_dev->lock held. */
207 	if (atomic_read(&ipmb_dev->request_queue_len) >=  in ipmb_handle_request()
215 	memcpy(&queue_elem->request, &ipmb_dev->request,  in ipmb_handle_request()
217 	list_add(&queue_elem->list, &ipmb_dev->request_queue);  in ipmb_handle_request()
218 	atomic_inc(&ipmb_dev->request_queue_len);  in ipmb_handle_request()
219 	wake_up_all(&ipmb_dev->wait_queue);  in ipmb_handle_request()
225 	return (rs_sa + ipmb_dev->request.netfn_rs_lun +  in ipmb_verify_checksum1()
226 		ipmb_dev->request.checksum1);  in ipmb_verify_checksum1()
235 	if ((ipmb_dev->msg_idx >= IPMB_REQUEST_LEN_MIN) &&  in is_ipmb_msg()
253 	u8 *buf = (u8 *)&ipmb_dev->request;  in ipmb_slave_cb()
256 	spin_lock_irqsave(&ipmb_dev->lock, flags);  in ipmb_slave_cb()
259 		memset(&ipmb_dev->request, 0, sizeof(ipmb_dev->request));  in ipmb_slave_cb()
260 		ipmb_dev->msg_idx = 0;  in ipmb_slave_cb()
278 		buf[++ipmb_dev->msg_idx] = GET_8BIT_ADDR(client->addr);  in ipmb_slave_cb()
282 		if (ipmb_dev->msg_idx >= sizeof(struct ipmb_msg) - 1)  in ipmb_slave_cb()
285 		buf[++ipmb_dev->msg_idx] = *val;  in ipmb_slave_cb()
289 		ipmb_dev->request.len = ipmb_dev->msg_idx;  in ipmb_slave_cb()
290 		if (is_ipmb_msg(ipmb_dev, GET_8BIT_ADDR(client->addr)))  in ipmb_slave_cb()
297 	spin_unlock_irqrestore(&ipmb_dev->lock, flags);  in ipmb_slave_cb()
307 	ipmb_dev = devm_kzalloc(&client->dev, sizeof(*ipmb_dev),  in ipmb_probe()
310 		return -ENOMEM;  in ipmb_probe()
312 	spin_lock_init(&ipmb_dev->lock);  in ipmb_probe()
313 	init_waitqueue_head(&ipmb_dev->wait_queue);  in ipmb_probe()
314 	atomic_set(&ipmb_dev->request_queue_len, 0);  in ipmb_probe()
315 	INIT_LIST_HEAD(&ipmb_dev->request_queue);  in ipmb_probe()
317 	mutex_init(&ipmb_dev->file_mutex);  in ipmb_probe()
319 	ipmb_dev->miscdev.minor = MISC_DYNAMIC_MINOR;  in ipmb_probe()
321 	ipmb_dev->miscdev.name = devm_kasprintf(&client->dev, GFP_KERNEL,  in ipmb_probe()
322 						"%s%d", "ipmb-",  in ipmb_probe()
323 						client->adapter->nr);  in ipmb_probe()
324 	if (!ipmb_dev->miscdev.name)  in ipmb_probe()
325 		return -ENOMEM;  in ipmb_probe()
327 	ipmb_dev->miscdev.fops = &ipmb_fops;  in ipmb_probe()
328 	ipmb_dev->miscdev.parent = &client->dev;  in ipmb_probe()
329 	ret = misc_register(&ipmb_dev->miscdev);  in ipmb_probe()
333 	ipmb_dev->is_i2c_protocol  in ipmb_probe()
334 		= device_property_read_bool(&client->dev, "i2c-protocol");  in ipmb_probe()
336 	ipmb_dev->client = client;  in ipmb_probe()
340 		misc_deregister(&ipmb_dev->miscdev);  in ipmb_probe()
352 	misc_deregister(&ipmb_dev->miscdev);  in ipmb_remove()
356 	{ "ipmb-dev" },
371 		.name = "ipmb-dev",