1 // SPDX-License-Identifier: GPL-2.0-or-later
14  * Note: Although this driver assumes a 16550A-like UART implementation,
89 	int index, ret = -EBUSY;  in sdio_uart_add_port()
91 	mutex_init(&port->func_lock);  in sdio_uart_add_port()
92 	spin_lock_init(&port->write_lock);  in sdio_uart_add_port()
93 	if (kfifo_alloc(&port->xmit_fifo, FIFO_SIZE, GFP_KERNEL))  in sdio_uart_add_port()
94 		return -ENOMEM;  in sdio_uart_add_port()
99 			port->index = index;  in sdio_uart_add_port()
120 		tty_port_get(&port->port);  in sdio_uart_port_get()
128 	tty_port_put(&port->port);  in sdio_uart_port_put()
136 	sdio_uart_table[port->index] = NULL;  in sdio_uart_port_remove()
146 	mutex_lock(&port->port.mutex);  in sdio_uart_port_remove()
147 	mutex_lock(&port->func_lock);  in sdio_uart_port_remove()
148 	func = port->func;  in sdio_uart_port_remove()
150 	port->func = NULL;  in sdio_uart_port_remove()
151 	mutex_unlock(&port->func_lock);  in sdio_uart_port_remove()
153 	tty_port_tty_hangup(&port->port, false);  in sdio_uart_port_remove()
154 	mutex_unlock(&port->port.mutex);  in sdio_uart_port_remove()
164 	mutex_lock(&port->func_lock);  in sdio_uart_claim_func()
165 	if (unlikely(!port->func)) {  in sdio_uart_claim_func()
166 		mutex_unlock(&port->func_lock);  in sdio_uart_claim_func()
167 		return -ENODEV;  in sdio_uart_claim_func()
169 	if (likely(port->in_sdio_uart_irq != current))  in sdio_uart_claim_func()
170 		sdio_claim_host(port->func);  in sdio_uart_claim_func()
171 	mutex_unlock(&port->func_lock);  in sdio_uart_claim_func()
177 	if (likely(port->in_sdio_uart_irq != current))  in sdio_uart_release_func()
178 		sdio_release_host(port->func);  in sdio_uart_release_func()
183 	return sdio_readb(port->func, port->regs_offset + offset, NULL);  in sdio_in()
188 	sdio_writeb(port->func, value, port->regs_offset + offset, NULL);  in sdio_out()
236 	old = port->mctrl;  in sdio_uart_update_mctrl()
237 	port->mctrl = (old & ~clear) | set;  in sdio_uart_update_mctrl()
238 	if (old != port->mctrl)  in sdio_uart_update_mctrl()
239 		sdio_uart_write_mctrl(port, port->mctrl);  in sdio_uart_update_mctrl()
252 	cval = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag));  in sdio_uart_change_speed()
254 	if (termios->c_cflag & CSTOPB)  in sdio_uart_change_speed()
256 	if (termios->c_cflag & PARENB)  in sdio_uart_change_speed()
258 	if (!(termios->c_cflag & PARODD))  in sdio_uart_change_speed()
265 		if (baud <= port->uartclk)  in sdio_uart_change_speed()
271 		termios->c_cflag &= ~CBAUD;  in sdio_uart_change_speed()
273 			termios->c_cflag |= old->c_cflag & CBAUD;  in sdio_uart_change_speed()
276 			termios->c_cflag |= B9600;  in sdio_uart_change_speed()
278 	quot = (2 * port->uartclk + baud) / (2 * baud);  in sdio_uart_change_speed()
285 	port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;  in sdio_uart_change_speed()
286 	if (termios->c_iflag & INPCK)  in sdio_uart_change_speed()
287 		port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;  in sdio_uart_change_speed()
288 	if (termios->c_iflag & (BRKINT | PARMRK))  in sdio_uart_change_speed()
289 		port->read_status_mask |= UART_LSR_BI;  in sdio_uart_change_speed()
294 	port->ignore_status_mask = 0;  in sdio_uart_change_speed()
295 	if (termios->c_iflag & IGNPAR)  in sdio_uart_change_speed()
296 		port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;  in sdio_uart_change_speed()
297 	if (termios->c_iflag & IGNBRK) {  in sdio_uart_change_speed()
298 		port->ignore_status_mask |= UART_LSR_BI;  in sdio_uart_change_speed()
301 		 * ignore overruns too (for real raw support).  in sdio_uart_change_speed()
303 		if (termios->c_iflag & IGNPAR)  in sdio_uart_change_speed()
304 			port->ignore_status_mask |= UART_LSR_OE;  in sdio_uart_change_speed()
310 	if ((termios->c_cflag & CREAD) == 0)  in sdio_uart_change_speed()
311 		port->ignore_status_mask |= UART_LSR_DR;  in sdio_uart_change_speed()
316 	port->ier &= ~UART_IER_MSI;  in sdio_uart_change_speed()
317 	if ((termios->c_cflag & CRTSCTS) || !(termios->c_cflag & CLOCAL))  in sdio_uart_change_speed()
318 		port->ier |= UART_IER_MSI;  in sdio_uart_change_speed()
320 	port->lcr = cval;  in sdio_uart_change_speed()
322 	sdio_out(port, UART_IER, port->ier);  in sdio_uart_change_speed()
329 	sdio_uart_write_mctrl(port, port->mctrl);  in sdio_uart_change_speed()
334 	if (!(port->ier & UART_IER_THRI)) {  in sdio_uart_start_tx()
335 		port->ier |= UART_IER_THRI;  in sdio_uart_start_tx()
336 		sdio_out(port, UART_IER, port->ier);  in sdio_uart_start_tx()
342 	if (port->ier & UART_IER_THRI) {  in sdio_uart_stop_tx()
343 		port->ier &= ~UART_IER_THRI;  in sdio_uart_stop_tx()
344 		sdio_out(port, UART_IER, port->ier);  in sdio_uart_stop_tx()
350 	port->ier &= ~UART_IER_RLSI;  in sdio_uart_stop_rx()
351 	port->read_status_mask &= ~UART_LSR_DR;  in sdio_uart_stop_rx()
352 	sdio_out(port, UART_IER, port->ier);  in sdio_uart_stop_rx()
362 		port->icount.rx++;  in sdio_uart_receive_chars()
371 				port->icount.brk++;  in sdio_uart_receive_chars()
373 				port->icount.parity++;  in sdio_uart_receive_chars()
375 				port->icount.frame++;  in sdio_uart_receive_chars()
377 				port->icount.overrun++;  in sdio_uart_receive_chars()
382 			*status &= port->read_status_mask;  in sdio_uart_receive_chars()
391 		if ((*status & port->ignore_status_mask & ~UART_LSR_OE) == 0)  in sdio_uart_receive_chars()
392 			tty_insert_flip_char(&port->port, ch, flag);  in sdio_uart_receive_chars()
398 		if (*status & ~port->ignore_status_mask & UART_LSR_OE)  in sdio_uart_receive_chars()
399 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);  in sdio_uart_receive_chars()
402 	} while ((*status & UART_LSR_DR) && (max_count-- > 0));  in sdio_uart_receive_chars()
404 	tty_flip_buffer_push(&port->port);  in sdio_uart_receive_chars()
409 	struct kfifo *xmit = &port->xmit_fifo;  in sdio_uart_transmit_chars()
415 	if (port->x_char) {  in sdio_uart_transmit_chars()
416 		sdio_out(port, UART_TX, port->x_char);  in sdio_uart_transmit_chars()
417 		port->icount.tx++;  in sdio_uart_transmit_chars()
418 		port->x_char = 0;  in sdio_uart_transmit_chars()
422 	tty = tty_port_tty_get(&port->port);  in sdio_uart_transmit_chars()
425 				tty->flow.stopped || tty->hw_stopped) {  in sdio_uart_transmit_chars()
431 	len = kfifo_out_locked(xmit, iobuf, 16, &port->write_lock);  in sdio_uart_transmit_chars()
434 		port->icount.tx++;  in sdio_uart_transmit_chars()
457 		port->icount.rng++;  in sdio_uart_check_modem_status()
459 		port->icount.dsr++;  in sdio_uart_check_modem_status()
461 		port->icount.dcd++;  in sdio_uart_check_modem_status()
462 		/* DCD raise - wake for open */  in sdio_uart_check_modem_status()
464 			wake_up_interruptible(&port->port.open_wait);  in sdio_uart_check_modem_status()
466 			/* DCD drop - hang up if tty attached */  in sdio_uart_check_modem_status()
467 			tty_port_tty_hangup(&port->port, false);  in sdio_uart_check_modem_status()
471 		port->icount.cts++;  in sdio_uart_check_modem_status()
472 		tty = tty_port_tty_get(&port->port);  in sdio_uart_check_modem_status()
475 			if (tty->hw_stopped) {  in sdio_uart_check_modem_status()
477 					tty->hw_stopped = false;  in sdio_uart_check_modem_status()
483 					tty->hw_stopped = true;  in sdio_uart_check_modem_status()
508 	if (unlikely(port->in_sdio_uart_irq == current))  in sdio_uart_irq()
515 	port->in_sdio_uart_irq = current;  in sdio_uart_irq()
522 	port->in_sdio_uart_irq = NULL;  in sdio_uart_irq()
539  *	uart_dtr_rts		-	 port helper to set uart signals
562  *	sdio_uart_activate	-	start up hardware
583 	 * Set the TTY IO error marker - we will only clear this  in sdio_uart_activate()
586 	set_bit(TTY_IO_ERROR, &tty->flags);  in sdio_uart_activate()
588 	kfifo_reset(&port->xmit_fifo);  in sdio_uart_activate()
593 	ret = sdio_enable_func(port->func);  in sdio_uart_activate()
596 	ret = sdio_claim_irq(port->func, sdio_uart_irq);  in sdio_uart_activate()
622 	port->ier = UART_IER_RLSI|UART_IER_RDI|UART_IER_RTOIE|UART_IER_UUE;  in sdio_uart_activate()
623 	port->mctrl = TIOCM_OUT2;  in sdio_uart_activate()
625 	sdio_uart_change_speed(port, &tty->termios, NULL);  in sdio_uart_activate()
632 			tty->hw_stopped = true;  in sdio_uart_activate()
634 	clear_bit(TTY_IO_ERROR, &tty->flags);  in sdio_uart_activate()
637 	sdio_uart_irq(port->func);  in sdio_uart_activate()
643 	sdio_disable_func(port->func);  in sdio_uart_activate()
650  *	sdio_uart_shutdown	-	stop hardware
672 	sdio_release_irq(port->func);  in sdio_uart_shutdown()
673 	port->ier = 0;  in sdio_uart_shutdown()
679 	port->lcr &= ~UART_LCR_SBC;  in sdio_uart_shutdown()
680 	sdio_out(port, UART_LCR, port->lcr);  in sdio_uart_shutdown()
686 	sdio_disable_func(port->func);  in sdio_uart_shutdown()
695 	kfifo_free(&port->xmit_fifo);  in sdio_uart_port_destroy()
700  *	sdio_uart_install	-	install method
710 	int idx = tty->index;  in sdio_uart_install()
716 		tty->driver_data = port;  in sdio_uart_install()
723  *	sdio_uart_cleanup	-	called on the last tty kref drop
727  *	We cannot destroy the tty->driver_data port kref until this point
732 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_cleanup()
733 	tty->driver_data = NULL;	/* Bug trap */  in sdio_uart_cleanup()
743 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_open()
744 	return tty_port_open(&port->port, tty, filp);  in sdio_uart_open()
749 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_close()
750 	tty_port_close(&port->port, tty, filp);  in sdio_uart_close()
755 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_hangup()
756 	tty_port_hangup(&port->port);  in sdio_uart_hangup()
762 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_write()
765 	if (!port->func)  in sdio_uart_write()
766 		return -ENODEV;  in sdio_uart_write()
768 	ret = kfifo_in_locked(&port->xmit_fifo, buf, count, &port->write_lock);  in sdio_uart_write()
769 	if (!(port->ier & UART_IER_THRI)) {  in sdio_uart_write()
773 			sdio_uart_irq(port->func);  in sdio_uart_write()
784 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_write_room()
785 	return FIFO_SIZE - kfifo_len(&port->xmit_fifo);  in sdio_uart_write_room()
790 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_chars_in_buffer()
791 	return kfifo_len(&port->xmit_fifo);  in sdio_uart_chars_in_buffer()
796 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_send_xchar()
798 	port->x_char = ch;  in sdio_uart_send_xchar()
799 	if (ch && !(port->ier & UART_IER_THRI)) {  in sdio_uart_send_xchar()
803 		sdio_uart_irq(port->func);  in sdio_uart_send_xchar()
810 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_throttle()
819 		port->x_char = STOP_CHAR(tty);  in sdio_uart_throttle()
826 	sdio_uart_irq(port->func);  in sdio_uart_throttle()
832 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_unthrottle()
841 		if (port->x_char) {  in sdio_uart_unthrottle()
842 			port->x_char = 0;  in sdio_uart_unthrottle()
844 			port->x_char = START_CHAR(tty);  in sdio_uart_unthrottle()
852 	sdio_uart_irq(port->func);  in sdio_uart_unthrottle()
859 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_set_termios()
860 	unsigned int cflag = tty->termios.c_cflag;  in sdio_uart_set_termios()
865 	sdio_uart_change_speed(port, &tty->termios, old_termios);  in sdio_uart_set_termios()
868 	if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD))  in sdio_uart_set_termios()
872 	if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {  in sdio_uart_set_termios()
880 	if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) {  in sdio_uart_set_termios()
881 		tty->hw_stopped = false;  in sdio_uart_set_termios()
886 	if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {  in sdio_uart_set_termios()
888 			tty->hw_stopped = true;  in sdio_uart_set_termios()
898 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_break_ctl()
905 	if (break_state == -1)  in sdio_uart_break_ctl()
906 		port->lcr |= UART_LCR_SBC;  in sdio_uart_break_ctl()
908 		port->lcr &= ~UART_LCR_SBC;  in sdio_uart_break_ctl()
909 	sdio_out(port, UART_LCR, port->lcr);  in sdio_uart_break_ctl()
917 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_tiocmget()
922 		result = port->mctrl | sdio_uart_get_mctrl(port);  in sdio_uart_tiocmget()
932 	struct sdio_uart_port *port = tty->driver_data;  in sdio_uart_tiocmset()
956 					      port->icount.tx, port->icount.rx);  in sdio_uart_proc_show()
957 				if (port->icount.frame)  in sdio_uart_proc_show()
959 						      port->icount.frame);  in sdio_uart_proc_show()
960 				if (port->icount.parity)  in sdio_uart_proc_show()
962 						      port->icount.parity);  in sdio_uart_proc_show()
963 				if (port->icount.brk)  in sdio_uart_proc_show()
965 						      port->icount.brk);  in sdio_uart_proc_show()
966 				if (port->icount.overrun)  in sdio_uart_proc_show()
968 						      port->icount.overrun);  in sdio_uart_proc_show()
969 				if (port->icount.cts)  in sdio_uart_proc_show()
971 						      port->icount.cts);  in sdio_uart_proc_show()
972 				if (port->icount.dsr)  in sdio_uart_proc_show()
974 						      port->icount.dsr);  in sdio_uart_proc_show()
975 				if (port->icount.rng)  in sdio_uart_proc_show()
977 						      port->icount.rng);  in sdio_uart_proc_show()
978 				if (port->icount.dcd)  in sdio_uart_proc_show()
980 						      port->icount.dcd);  in sdio_uart_proc_show()
1026 		return -ENOMEM;  in sdio_uart_probe()
1028 	if (func->class == SDIO_CLASS_UART) {  in sdio_uart_probe()
1032 		return -ENOSYS;  in sdio_uart_probe()
1033 	} else if (func->class == SDIO_CLASS_GPS) {  in sdio_uart_probe()
1038 		struct sdio_func_tuple *tpl;  in sdio_uart_probe()  local
1039 		for (tpl = func->tuples; tpl; tpl = tpl->next) {  in sdio_uart_probe()
1040 			if (tpl->code != 0x91)  in sdio_uart_probe()
1042 			if (tpl->size < 10)  in sdio_uart_probe()
1044 			if (tpl->data[1] == 0)  /* SUBTPL_SIOREG */  in sdio_uart_probe()
1047 		if (!tpl) {  in sdio_uart_probe()
1051 			return -EINVAL;  in sdio_uart_probe()
1054 		       sdio_func_id(func), tpl->data[2], tpl->data[3]);  in sdio_uart_probe()
1055 		port->regs_offset = (tpl->data[4] << 0) |  in sdio_uart_probe()
1056 				    (tpl->data[5] << 8) |  in sdio_uart_probe()
1057 				    (tpl->data[6] << 16);  in sdio_uart_probe()
1059 		       sdio_func_id(func), port->regs_offset);  in sdio_uart_probe()
1060 		port->uartclk = tpl->data[7] * 115200;  in sdio_uart_probe()
1061 		if (port->uartclk == 0)  in sdio_uart_probe()
1062 			port->uartclk = 115200;  in sdio_uart_probe()
1063 		pr_debug("%s: clk %d baudcode %u 4800-div %u\n",  in sdio_uart_probe()
1064 		       sdio_func_id(func), port->uartclk,  in sdio_uart_probe()
1065 		       tpl->data[7], tpl->data[8] | (tpl->data[9] << 8));  in sdio_uart_probe()
1068 		return -EINVAL;  in sdio_uart_probe()
1071 	port->func = func;  in sdio_uart_probe()
1073 	tty_port_init(&port->port);  in sdio_uart_probe()
1074 	port->port.ops = &sdio_uart_port_ops;  in sdio_uart_probe()
1081 		dev = tty_port_register_device(&port->port,  in sdio_uart_probe()
1082 				sdio_uart_tty_driver, port->index, &func->dev);  in sdio_uart_probe()
1096 	tty_unregister_device(sdio_uart_tty_driver, port->index);  in sdio_uart_remove()
1125 	tty_drv->driver_name = "sdio_uart";  in sdio_uart_init()
1126 	tty_drv->name =   "ttySDIO";  in sdio_uart_init()
1127 	tty_drv->major = 0;  /* dynamically allocated */  in sdio_uart_init()
1128 	tty_drv->minor_start = 0;  in sdio_uart_init()
1129 	tty_drv->type = TTY_DRIVER_TYPE_SERIAL;  in sdio_uart_init()
1130 	tty_drv->subtype = SERIAL_TYPE_NORMAL;  in sdio_uart_init()
1131 	tty_drv->init_termios = tty_std_termios;  in sdio_uart_init()
1132 	tty_drv->init_termios.c_cflag = B4800 | CS8 | CREAD | HUPCL | CLOCAL;  in sdio_uart_init()
1133 	tty_drv->init_termios.c_ispeed = 4800;  in sdio_uart_init()
1134 	tty_drv->init_termios.c_ospeed = 4800;  in sdio_uart_init()