drivers/tty/ehv_bytechan.c

86 static void enable_tx_interrupt(struct ehv_bc_data *bc)
88 	if (!bc->tx_irq_enabled) {
89 		enable_irq(bc->tx_irq);
90 		bc->tx_irq_enabled = 1;
94 static void disable_tx_interrupt(struct ehv_bc_data *bc)
96 	if (bc->tx_irq_enabled) {
97 		disable_irq_nosync(bc->tx_irq);
98 		bc->tx_irq_enabled = 0;
122 		pr_err("ehv-bc: no 'interrupts' property in %pOF node\n", np);
131 		pr_err("ehv-bc: no 'hv-handle' property in %pOFn node\n",
217 	udbg_printf("ehv-bc: early console using byte channel handle %u\n",
316 		pr_debug("ehv-bc: stdout is not a byte channel\n");
325 		pr_warn("ehv-bc: udbg handle %u is not the stdout handle\n",
336 	pr_info("ehv-bc: registered console driver for byte channel %u\n",
352 	struct ehv_bc_data *bc = data;
362 	ev_byte_channel_poll(bc->handle, &rx_count, &tx_count);
363 	count = tty_buffer_request_room(&bc->port, rx_count);
377 		ev_byte_channel_receive(bc->handle, &len, buffer);
384 		ret = tty_insert_flip_string(&bc->port, buffer, len);
399 	tty_flip_buffer_push(&bc->port);
410 static void ehv_bc_tx_dequeue(struct ehv_bc_data *bc)
417 		spin_lock_irqsave(&bc->lock, flags);
419 			    CIRC_CNT_TO_END(bc->head, bc->tail, BUF_SIZE),
422 		ret = local_ev_byte_channel_send(bc->handle, &len, bc->buf + bc->tail);
426 			bc->tail = (bc->tail + len) & (BUF_SIZE - 1);
428 		count = CIRC_CNT(bc->head, bc->tail, BUF_SIZE);
429 		spin_unlock_irqrestore(&bc->lock, flags);
432 	spin_lock_irqsave(&bc->lock, flags);
433 	if (CIRC_CNT(bc->head, bc->tail, BUF_SIZE))
439 		enable_tx_interrupt(bc);
441 		disable_tx_interrupt(bc);
442 	spin_unlock_irqrestore(&bc->lock, flags);
453 	struct ehv_bc_data *bc = data;
455 	ehv_bc_tx_dequeue(bc);
456 	tty_port_tty_wakeup(&bc->port);
475 	struct ehv_bc_data *bc = ttys->driver_data;
480 		spin_lock_irqsave(&bc->lock, flags);
481 		len = CIRC_SPACE_TO_END(bc->head, bc->tail, BUF_SIZE);
485 			memcpy(bc->buf + bc->head, s, len);
486 			bc->head = (bc->head + len) & (BUF_SIZE - 1);
488 		spin_unlock_irqrestore(&bc->lock, flags);
497 	ehv_bc_tx_dequeue(bc);
504  * why we initialize bc->ttys in ehv_bc_tty_port_activate() instead.
513 	struct ehv_bc_data *bc = &bcs[ttys->index];
515 	if (!bc->dev)
518 	return tty_port_open(&bc->port, ttys, filp);
528 	struct ehv_bc_data *bc = &bcs[ttys->index];
530 	if (bc->dev)
531 		tty_port_close(&bc->port, ttys, filp);
543 	struct ehv_bc_data *bc = ttys->driver_data;
547 	spin_lock_irqsave(&bc->lock, flags);
548 	count = CIRC_SPACE(bc->head, bc->tail, BUF_SIZE);
549 	spin_unlock_irqrestore(&bc->lock, flags);
568 	struct ehv_bc_data *bc = ttys->driver_data;
570 	disable_irq(bc->rx_irq);
582 	struct ehv_bc_data *bc = ttys->driver_data;
587 	enable_irq(bc->rx_irq);
592 	struct ehv_bc_data *bc = ttys->driver_data;
594 	ehv_bc_tx_dequeue(bc);
595 	tty_port_hangup(&bc->port);
625 	struct ehv_bc_data *bc = container_of(port, struct ehv_bc_data, port);
628 	ttys->driver_data = bc;
630 	ret = request_irq(bc->rx_irq, ehv_bc_tty_rx_isr, 0, "ehv-bc", bc);
632 		dev_err(bc->dev, "could not request rx irq %u (ret=%i)\n",
633 		       bc->rx_irq, ret);
638 	bc->tx_irq_enabled = 1;
640 	ret = request_irq(bc->tx_irq, ehv_bc_tty_tx_isr, 0, "ehv-bc", bc);
642 		dev_err(bc->dev, "could not request tx irq %u (ret=%i)\n",
643 		       bc->tx_irq, ret);
644 		free_irq(bc->rx_irq, bc);
651 	disable_tx_interrupt(bc);
658 	struct ehv_bc_data *bc = container_of(port, struct ehv_bc_data, port);
660 	free_irq(bc->tx_irq, bc);
661 	free_irq(bc->rx_irq, bc);
672 	struct ehv_bc_data *bc;
692 	bc = &bcs[i];
694 	bc->handle = handle;
695 	bc->head = 0;
696 	bc->tail = 0;
697 	spin_lock_init(&bc->lock);
699 	bc->rx_irq = irq_of_parse_and_map(np, 0);
700 	bc->tx_irq = irq_of_parse_and_map(np, 1);
701 	if (!bc->rx_irq || !bc->tx_irq) {
708 	tty_port_init(&bc->port);
709 	bc->port.ops = &ehv_bc_tty_port_ops;
711 	bc->dev = tty_port_register_device(&bc->port, ehv_bc_driver, i,
713 	if (IS_ERR(bc->dev)) {
714 		ret = PTR_ERR(bc->dev);
719 	dev_set_drvdata(&pdev->dev, bc);
722 		ehv_bc_driver->name, i, bc->handle);
727 	tty_port_destroy(&bc->port);
728 	irq_dispose_mapping(bc->tx_irq);
729 	irq_dispose_mapping(bc->rx_irq);
731 	memset(bc, 0, sizeof(struct ehv_bc_data));
742 		.name = "ehv-bc",
772 	 * array, then you can use pointer math (e.g. "bc - bcs") to get its
786 	driver->driver_name = "ehv-bc";
795 		pr_err("ehv-bc: could not register tty driver (ret=%i)\n", ret);
803 		pr_err("ehv-bc: could not register platform driver (ret=%i)\n",