1 // SPDX-License-Identifier: GPL-2.0-only
3  * Driver for the Diolan DLN-2 USB adapter
8  *  i2c-diolan-u2c.c
9  *  Copyright (c) 2010-2011 Ericsson AB
66 	/* if non-NULL the URB contains the response */
76  * the echo header field to index the slots field and find the receive context
80 	/* RX slots bitmap */
83 	/* used to wait for a free RX slot */
86 	/* used to wait for an RX operation to complete */
87 	struct dln2_rx_context slots[DLN2_MAX_RX_SLOTS];  member
123 	struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);  in dln2_register_event_cb()
130 		return -ENOMEM;  in dln2_register_event_cb()
132 	entry->id = id;  in dln2_register_event_cb()
133 	entry->callback = event_cb;  in dln2_register_event_cb()
134 	entry->pdev = pdev;  in dln2_register_event_cb()
136 	spin_lock_irqsave(&dln2->event_cb_lock, flags);  in dln2_register_event_cb()
138 	list_for_each_entry(i, &dln2->event_cb_list, list) {  in dln2_register_event_cb()
139 		if (i->id == id) {  in dln2_register_event_cb()
140 			ret = -EBUSY;  in dln2_register_event_cb()
146 		list_add_rcu(&entry->list, &dln2->event_cb_list);  in dln2_register_event_cb()
148 	spin_unlock_irqrestore(&dln2->event_cb_lock, flags);  in dln2_register_event_cb()
159 	struct dln2_dev *dln2 = dev_get_drvdata(pdev->dev.parent);  in dln2_unregister_event_cb()
164 	spin_lock_irqsave(&dln2->event_cb_lock, flags);  in dln2_unregister_event_cb()
166 	list_for_each_entry(i, &dln2->event_cb_list, list) {  in dln2_unregister_event_cb()
167 		if (i->id == id) {  in dln2_unregister_event_cb()
168 			list_del_rcu(&i->list);  in dln2_unregister_event_cb()
174 	spin_unlock_irqrestore(&dln2->event_cb_lock, flags);  in dln2_unregister_event_cb()
191 	struct device *dev = &dln2->interface->dev;  in dln2_transfer_complete()
192 	struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];  in dln2_transfer_complete()
200 	rxc = &rxs->slots[rx_slot];  in dln2_transfer_complete()
202 	spin_lock_irqsave(&rxs->lock, flags);  in dln2_transfer_complete()
203 	if (rxc->in_use && !rxc->urb) {  in dln2_transfer_complete()
204 		rxc->urb = urb;  in dln2_transfer_complete()
205 		complete(&rxc->done);  in dln2_transfer_complete()
208 	spin_unlock_irqrestore(&rxs->lock, flags);  in dln2_transfer_complete()
224 	list_for_each_entry_rcu(i, &dln2->event_cb_list, list) {  in dln2_run_event_callbacks()
225 		if (i->id == id) {  in dln2_run_event_callbacks()
226 			i->callback(i->pdev, echo, data, len);  in dln2_run_event_callbacks()
236 	struct dln2_dev *dln2 = urb->context;  in dln2_rx()
237 	struct dln2_header *hdr = urb->transfer_buffer;  in dln2_rx()
238 	struct device *dev = &dln2->interface->dev;  in dln2_rx()
244 	switch (urb->status) {  in dln2_rx()
248 	case -ECONNRESET:  in dln2_rx()
249 	case -ENOENT:  in dln2_rx()
250 	case -ESHUTDOWN:  in dln2_rx()
251 	case -EPIPE:  in dln2_rx()
253 		dev_dbg(dev, "urb shutting down with status %d\n", urb->status);  in dln2_rx()
256 		dev_dbg(dev, "nonzero urb status received %d\n", urb->status);  in dln2_rx()
260 	if (urb->actual_length < sizeof(struct dln2_header)) {  in dln2_rx()
261 		dev_err(dev, "short response: %d\n", urb->actual_length);  in dln2_rx()
265 	handle = le16_to_cpu(hdr->handle);  in dln2_rx()
266 	id = le16_to_cpu(hdr->id);  in dln2_rx()
267 	echo = le16_to_cpu(hdr->echo);  in dln2_rx()
268 	size = le16_to_cpu(hdr->size);  in dln2_rx()
270 	if (size != urb->actual_length) {  in dln2_rx()
272 			handle, id, echo, size, urb->actual_length);  in dln2_rx()
281 	data = urb->transfer_buffer + sizeof(struct dln2_header);  in dln2_rx()
282 	len = urb->actual_length - sizeof(struct dln2_header);  in dln2_rx()
287 		spin_lock_irqsave(&dln2->event_cb_lock, flags);  in dln2_rx()
289 		spin_unlock_irqrestore(&dln2->event_cb_lock, flags);  in dln2_rx()
291 		/* URB will be re-submitted in _dln2_transfer (free_rx_slot) */  in dln2_rx()
299 		dev_err(dev, "failed to resubmit RX URB: %d\n", err);  in dln2_rx()
315 	hdr->id = cpu_to_le16(cmd);  in dln2_prep_buf()
316 	hdr->size = cpu_to_le16(len);  in dln2_prep_buf()
317 	hdr->echo = cpu_to_le16(echo);  in dln2_prep_buf()
318 	hdr->handle = cpu_to_le16(handle);  in dln2_prep_buf()
337 		return -ENOMEM;  in dln2_send_wait()
339 	ret = usb_bulk_msg(dln2->usb_dev,  in dln2_send_wait()
340 			   usb_sndbulkpipe(dln2->usb_dev, dln2->ep_out),  in dln2_send_wait()
353 	if (dln2->disconnect) {  in find_free_slot()
354 		*slot = -ENODEV;  in find_free_slot()
358 	rxs = &dln2->mod_rx_slots[handle];  in find_free_slot()
360 	spin_lock_irqsave(&rxs->lock, flags);  in find_free_slot()
362 	*slot = find_first_zero_bit(rxs->bmap, DLN2_MAX_RX_SLOTS);  in find_free_slot()
365 		struct dln2_rx_context *rxc = &rxs->slots[*slot];  in find_free_slot()
367 		set_bit(*slot, rxs->bmap);  in find_free_slot()
368 		rxc->in_use = true;  in find_free_slot()
371 	spin_unlock_irqrestore(&rxs->lock, flags);  in find_free_slot()
385 	ret = wait_event_interruptible(dln2->mod_rx_slots[handle].wq,  in alloc_rx_slot()
400 	rxs = &dln2->mod_rx_slots[handle];  in free_rx_slot()
402 	spin_lock_irqsave(&rxs->lock, flags);  in free_rx_slot()
404 	clear_bit(slot, rxs->bmap);  in free_rx_slot()
406 	rxc = &rxs->slots[slot];  in free_rx_slot()
407 	rxc->in_use = false;  in free_rx_slot()
408 	urb = rxc->urb;  in free_rx_slot()
409 	rxc->urb = NULL;  in free_rx_slot()
410 	reinit_completion(&rxc->done);  in free_rx_slot()
412 	spin_unlock_irqrestore(&rxs->lock, flags);  in free_rx_slot()
416 		struct device *dev = &dln2->interface->dev;  in free_rx_slot()
420 			dev_err(dev, "failed to resubmit RX URB: %d\n", err);  in free_rx_slot()
423 	wake_up_interruptible(&rxs->wq);  in free_rx_slot()
434 	struct device *dev = &dln2->interface->dev;  in _dln2_transfer()
436 	struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[handle];  in _dln2_transfer()
439 	spin_lock(&dln2->disconnect_lock);  in _dln2_transfer()
440 	if (!dln2->disconnect)  in _dln2_transfer()
441 		dln2->active_transfers++;  in _dln2_transfer()
443 		ret = -ENODEV;  in _dln2_transfer()
444 	spin_unlock(&dln2->disconnect_lock);  in _dln2_transfer()
461 	rxc = &rxs->slots[rx_slot];  in _dln2_transfer()
463 	ret = wait_for_completion_interruptible_timeout(&rxc->done, timeout);  in _dln2_transfer()
466 			ret = -ETIMEDOUT;  in _dln2_transfer()
472 	if (dln2->disconnect) {  in _dln2_transfer()
473 		ret = -ENODEV;  in _dln2_transfer()
478 	rsp = rxc->urb->transfer_buffer;  in _dln2_transfer()
479 	size = le16_to_cpu(rsp->hdr.size);  in _dln2_transfer()
482 		ret = -EPROTO;  in _dln2_transfer()
486 	if (le16_to_cpu(rsp->result) > 0x80) {  in _dln2_transfer()
488 			handle, le16_to_cpu(rsp->result));  in _dln2_transfer()
489 		ret = -EREMOTEIO;  in _dln2_transfer()
496 	if (*ibuf_len > size - sizeof(*rsp))  in _dln2_transfer()
497 		*ibuf_len = size - sizeof(*rsp);  in _dln2_transfer()
504 	spin_lock(&dln2->disconnect_lock);  in _dln2_transfer()
505 	dln2->active_transfers--;  in _dln2_transfer()
506 	spin_unlock(&dln2->disconnect_lock);  in _dln2_transfer()
507 	if (dln2->disconnect)  in _dln2_transfer()
508 		wake_up(&dln2->disconnect_wq);  in _dln2_transfer()
521 	dln2 = dev_get_drvdata(pdev->dev.parent);  in dln2_transfer()
522 	dln2_pdata = dev_get_platdata(&pdev->dev);  in dln2_transfer()
523 	handle = dln2_pdata->handle;  in dln2_transfer()
541 		return -EREMOTEIO;  in dln2_check_hw()
544 		dev_err(&dln2->interface->dev, "Device ID 0x%x not supported\n",  in dln2_check_hw()
546 		return -ENODEV;  in dln2_check_hw()
557 	struct device *dev = &dln2->interface->dev;  in dln2_print_serialno()
564 		return -EREMOTEIO;  in dln2_print_serialno()
587 		usb_free_urb(dln2->rx_urb[i]);  in dln2_free_rx_urbs()
588 		kfree(dln2->rx_buf[i]);  in dln2_free_rx_urbs()
597 		usb_kill_urb(dln2->rx_urb[i]);  in dln2_stop_rx_urbs()
603 	usb_put_dev(dln2->usb_dev);  in dln2_free()
614 		dln2->rx_buf[i] = kmalloc(rx_max_size, GFP_KERNEL);  in dln2_setup_rx_urbs()
615 		if (!dln2->rx_buf[i])  in dln2_setup_rx_urbs()
616 			return -ENOMEM;  in dln2_setup_rx_urbs()
618 		dln2->rx_urb[i] = usb_alloc_urb(0, GFP_KERNEL);  in dln2_setup_rx_urbs()
619 		if (!dln2->rx_urb[i])  in dln2_setup_rx_urbs()
620 			return -ENOMEM;  in dln2_setup_rx_urbs()
622 		usb_fill_bulk_urb(dln2->rx_urb[i], dln2->usb_dev,  in dln2_setup_rx_urbs()
623 				  usb_rcvbulkpipe(dln2->usb_dev, dln2->ep_in),  in dln2_setup_rx_urbs()
624 				  dln2->rx_buf[i], rx_max_size, dln2_rx, dln2);  in dln2_setup_rx_urbs()
632 	struct device *dev = &dln2->interface->dev;  in dln2_start_rx_urbs()
637 		ret = usb_submit_urb(dln2->rx_urb[i], gfp);  in dln2_start_rx_urbs()
639 			dev_err(dev, "failed to submit RX URB: %d\n", ret);  in dln2_start_rx_urbs()
694 		.name = "dln2-gpio",
700 		.name = "dln2-i2c",
706 		.name = "dln2-spi",
712 		.name = "dln2-adc",
724 	spin_lock(&dln2->disconnect_lock);  in dln2_stop()
725 	dln2->disconnect = true;  in dln2_stop()
726 	spin_unlock(&dln2->disconnect_lock);  in dln2_stop()
730 		struct dln2_mod_rx_slots *rxs = &dln2->mod_rx_slots[i];  in dln2_stop()
733 		spin_lock_irqsave(&rxs->lock, flags);  in dln2_stop()
737 			struct dln2_rx_context *rxc = &rxs->slots[j];  in dln2_stop()
739 			if (rxc->in_use)  in dln2_stop()
740 				complete(&rxc->done);  in dln2_stop()
743 		spin_unlock_irqrestore(&rxs->lock, flags);  in dln2_stop()
747 	wait_event(dln2->disconnect_wq, !dln2->active_transfers);  in dln2_stop()
758 	mfd_remove_devices(&interface->dev);  in dln2_disconnect()
766 	struct usb_host_interface *hostif = interface->cur_altsetting;  in dln2_probe()
769 	struct device *dev = &interface->dev;  in dln2_probe()
774 	if (hostif->desc.bInterfaceNumber != 0)  in dln2_probe()
775 		return -ENODEV;  in dln2_probe()
783 		return -ENOMEM;  in dln2_probe()
785 	dln2->ep_out = epout->bEndpointAddress;  in dln2_probe()
786 	dln2->ep_in = epin->bEndpointAddress;  in dln2_probe()
787 	dln2->usb_dev = usb_get_dev(interface_to_usbdev(interface));  in dln2_probe()
788 	dln2->interface = interface;  in dln2_probe()
790 	init_waitqueue_head(&dln2->disconnect_wq);  in dln2_probe()
793 		init_waitqueue_head(&dln2->mod_rx_slots[i].wq);  in dln2_probe()
794 		spin_lock_init(&dln2->mod_rx_slots[i].lock);  in dln2_probe()
796 			init_completion(&dln2->mod_rx_slots[i].slots[j].done);  in dln2_probe()
799 	spin_lock_init(&dln2->event_cb_lock);  in dln2_probe()
800 	spin_lock_init(&dln2->disconnect_lock);  in dln2_probe()
801 	INIT_LIST_HEAD(&dln2->event_cb_list);  in dln2_probe()
847 	dln2->disconnect = false;  in dln2_resume()