mmc/core/sdio_uart.c

22  * concurrent access to the same port.
65 	struct tty_port		port;
87 static int sdio_uart_add_port(struct sdio_uart_port *port)
91 	mutex_init(&port->func_lock);
92 	spin_lock_init(&port->write_lock);
93 	if (kfifo_alloc(&port->xmit_fifo, FIFO_SIZE, GFP_KERNEL))
99 			port->index = index;
100 			sdio_uart_table[index] = port;
112 	struct sdio_uart_port *port;
118 	port = sdio_uart_table[index];
119 	if (port)
120 		tty_port_get(&port->port);
123 	return port;
126 static void sdio_uart_port_put(struct sdio_uart_port *port)
128 	tty_port_put(&port->port);
131 static void sdio_uart_port_remove(struct sdio_uart_port *port)
136 	sdio_uart_table[port->index] = NULL;
140 	 * We're killing a port that potentially still is in use by
143 	 * give up on that port ASAP.
146 	mutex_lock(&port->port.mutex);
147 	mutex_lock(&port->func_lock);
148 	func = port->func;
150 	port->func = NULL;
151 	mutex_unlock(&port->func_lock);
153 	tty_port_tty_hangup(&port->port, false);
154 	mutex_unlock(&port->port.mutex);
159 	sdio_uart_port_put(port);
162 static int sdio_uart_claim_func(struct sdio_uart_port *port)
164 	mutex_lock(&port->func_lock);
165 	if (unlikely(!port->func)) {
166 		mutex_unlock(&port->func_lock);
169 	if (likely(port->in_sdio_uart_irq != current))
170 		sdio_claim_host(port->func);
171 	mutex_unlock(&port->func_lock);
175 static inline void sdio_uart_release_func(struct sdio_uart_port *port)
177 	if (likely(port->in_sdio_uart_irq != current))
178 		sdio_release_host(port->func);
181 static inline u8 sdio_in(struct sdio_uart_port *port, int offset)
183 	return sdio_readb(port->func, port->regs_offset + offset, NULL);
186 static inline void sdio_out(struct sdio_uart_port *port, int offset, int value)
188 	sdio_writeb(port->func, value, port->regs_offset + offset, NULL);
191 static unsigned int sdio_uart_get_mctrl(struct sdio_uart_port *port)
198 	status = sdio_in(port, UART_MSR);
212 static void sdio_uart_write_mctrl(struct sdio_uart_port *port,
228 	sdio_out(port, UART_MCR, mcr);
231 static inline void sdio_uart_update_mctrl(struct sdio_uart_port *port,
236 	old = port->mctrl;
237 	port->mctrl = (old & ~clear) | set;
238 	if (old != port->mctrl)
239 		sdio_uart_write_mctrl(port, port->mctrl);
242 #define sdio_uart_set_mctrl(port, x)	sdio_uart_update_mctrl(port, x, 0)
243 #define sdio_uart_clear_mctrl(port, x)	sdio_uart_update_mctrl(port, 0, x)
245 static void sdio_uart_change_speed(struct sdio_uart_port *port,
265 		if (baud <= port->uartclk)
278 	quot = (2 * port->uartclk + baud) / (2 * baud);
285 	port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
287 		port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
289 		port->read_status_mask |= UART_LSR_BI;
294 	port->ignore_status_mask = 0;
296 		port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
298 		port->ignore_status_mask |= UART_LSR_BI;
304 			port->ignore_status_mask |= UART_LSR_OE;
311 		port->ignore_status_mask |= UART_LSR_DR;
316 	port->ier &= ~UART_IER_MSI;
318 		port->ier |= UART_IER_MSI;
320 	port->lcr = cval;
322 	sdio_out(port, UART_IER, port->ier);
323 	sdio_out(port, UART_LCR, cval | UART_LCR_DLAB);
324 	sdio_out(port, UART_DLL, quot & 0xff);
325 	sdio_out(port, UART_DLM, quot >> 8);
326 	sdio_out(port, UART_LCR, cval);
327 	sdio_out(port, UART_FCR, fcr);
329 	sdio_uart_write_mctrl(port, port->mctrl);
332 static void sdio_uart_start_tx(struct sdio_uart_port *port)
334 	if (!(port->ier & UART_IER_THRI)) {
335 		port->ier |= UART_IER_THRI;
336 		sdio_out(port, UART_IER, port->ier);
340 static void sdio_uart_stop_tx(struct sdio_uart_port *port)
342 	if (port->ier & UART_IER_THRI) {
343 		port->ier &= ~UART_IER_THRI;
344 		sdio_out(port, UART_IER, port->ier);
348 static void sdio_uart_stop_rx(struct sdio_uart_port *port)
350 	port->ier &= ~UART_IER_RLSI;
351 	port->read_status_mask &= ~UART_LSR_DR;
352 	sdio_out(port, UART_IER, port->ier);
355 static void sdio_uart_receive_chars(struct sdio_uart_port *port, u8 *status)
360 		u8 ch = sdio_in(port, UART_RX);
362 		port->icount.rx++;
371 				port->icount.brk++;
373 				port->icount.parity++;
375 				port->icount.frame++;
377 				port->icount.overrun++;
382 			*status &= port->read_status_mask;
391 		if ((*status & port->ignore_status_mask & ~UART_LSR_OE) == 0)
392 			tty_insert_flip_char(&port->port, ch, flag);
398 		if (*status & ~port->ignore_status_mask & UART_LSR_OE)
399 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
401 		*status = sdio_in(port, UART_LSR);
404 	tty_flip_buffer_push(&port->port);
407 static void sdio_uart_transmit_chars(struct sdio_uart_port *port)
409 	struct kfifo *xmit = &port->xmit_fifo;
415 	if (port->x_char) {
416 		sdio_out(port, UART_TX, port->x_char);
417 		port->icount.tx++;
418 		port->x_char = 0;
422 	tty = tty_port_tty_get(&port->port);
426 		sdio_uart_stop_tx(port);
431 	len = kfifo_out_locked(xmit, iobuf, 16, &port->write_lock);
433 		sdio_out(port, UART_TX, iobuf[count]);
434 		port->icount.tx++;
441 			sdio_uart_stop_tx(port);
446 static void sdio_uart_check_modem_status(struct sdio_uart_port *port)
451 	status = sdio_in(port, UART_MSR);
457 		port->icount.rng++;
459 		port->icount.dsr++;
461 		port->icount.dcd++;
464 			wake_up_interruptible(&port->port.open_wait);
467 			tty_port_tty_hangup(&port->port, false);
471 		port->icount.cts++;
472 		tty = tty_port_tty_get(&port->port);
478 					sdio_uart_start_tx(port);
484 					sdio_uart_stop_tx(port);
493  * This handles the interrupt from one port.
497 	struct sdio_uart_port *port = sdio_get_drvdata(func);
508 	if (unlikely(port->in_sdio_uart_irq == current))
511 	iir = sdio_in(port, UART_IIR);
515 	port->in_sdio_uart_irq = current;
516 	lsr = sdio_in(port, UART_LSR);
518 		sdio_uart_receive_chars(port, &lsr);
519 	sdio_uart_check_modem_status(port);
521 		sdio_uart_transmit_chars(port);
522 	port->in_sdio_uart_irq = NULL;
527 	struct sdio_uart_port *port =
528 			container_of(tport, struct sdio_uart_port, port);
529 	unsigned int ret = sdio_uart_claim_func(port);
532 	ret = sdio_uart_get_mctrl(port);
533 	sdio_uart_release_func(port);
539  *	uart_dtr_rts		-	 port helper to set uart signals
540  *	@tport: tty port to be updated
543  *	Called by the tty port helpers when the modem signals need to be
549 	struct sdio_uart_port *port =
550 			container_of(tport, struct sdio_uart_port, port);
551 	int ret = sdio_uart_claim_func(port);
555 		sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
557 		sdio_uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
558 	sdio_uart_release_func(port);
563  *	@tport: tty port to activate
564  *	@tty: tty bound to this port
566  *	Activate a tty port. The port locking guarantees us this will be
572  *	If we successfully start up the port we take an extra kref as we
578 	struct sdio_uart_port *port =
579 			container_of(tport, struct sdio_uart_port, port);
584 	 * once we have successfully opened the port.
588 	kfifo_reset(&port->xmit_fifo);
590 	ret = sdio_uart_claim_func(port);
593 	ret = sdio_enable_func(port->func);
596 	ret = sdio_claim_irq(port->func, sdio_uart_irq);
604 	sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
605 	sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO |
607 	sdio_out(port, UART_FCR, 0);
612 	(void) sdio_in(port, UART_LSR);
613 	(void) sdio_in(port, UART_RX);
614 	(void) sdio_in(port, UART_IIR);
615 	(void) sdio_in(port, UART_MSR);
620 	sdio_out(port, UART_LCR, UART_LCR_WLEN8);
622 	port->ier = UART_IER_RLSI|UART_IER_RDI|UART_IER_RTOIE|UART_IER_UUE;
623 	port->mctrl = TIOCM_OUT2;
625 	sdio_uart_change_speed(port, &tty->termios, NULL);
628 		sdio_uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
631 		if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS))
637 	sdio_uart_irq(port->func);
639 	sdio_uart_release_func(port);
643 	sdio_disable_func(port->func);
645 	sdio_uart_release_func(port);
651  *	@tport: tty port to shut down
653  *	Deactivate a tty port. The port locking guarantees us this will be
661 	struct sdio_uart_port *port =
662 			container_of(tport, struct sdio_uart_port, port);
665 	ret = sdio_uart_claim_func(port);
669 	sdio_uart_stop_rx(port);
671 	/* Disable interrupts from this port */
672 	sdio_release_irq(port->func);
673 	port->ier = 0;
674 	sdio_out(port, UART_IER, 0);
676 	sdio_uart_clear_mctrl(port, TIOCM_OUT2);
679 	port->lcr &= ~UART_LCR_SBC;
680 	sdio_out(port, UART_LCR, port->lcr);
681 	sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO |
684 	sdio_out(port, UART_FCR, 0);
686 	sdio_disable_func(port->func);
688 	sdio_uart_release_func(port);
693 	struct sdio_uart_port *port =
694 		container_of(tport, struct sdio_uart_port, port);
695 	kfifo_free(&port->xmit_fifo);
696 	kfree(port);
711 	struct sdio_uart_port *port = sdio_uart_port_get(idx);
716 		tty->driver_data = port;
718 		sdio_uart_port_put(port);
727  *	We cannot destroy the tty->driver_data port kref until this point
732 	struct sdio_uart_port *port = tty->driver_data;
734 	sdio_uart_port_put(port);
743 	struct sdio_uart_port *port = tty->driver_data;
744 	return tty_port_open(&port->port, tty, filp);
749 	struct sdio_uart_port *port = tty->driver_data;
750 	tty_port_close(&port->port, tty, filp);
755 	struct sdio_uart_port *port = tty->driver_data;
756 	tty_port_hangup(&port->port);
762 	struct sdio_uart_port *port = tty->driver_data;
765 	if (!port->func)
768 	ret = kfifo_in_locked(&port->xmit_fifo, buf, count, &port->write_lock);
769 	if (!(port->ier & UART_IER_THRI)) {
770 		int err = sdio_uart_claim_func(port);
772 			sdio_uart_start_tx(port);
773 			sdio_uart_irq(port->func);
774 			sdio_uart_release_func(port);
784 	struct sdio_uart_port *port = tty->driver_data;
785 	return FIFO_SIZE - kfifo_len(&port->xmit_fifo);
790 	struct sdio_uart_port *port = tty->driver_data;
791 	return kfifo_len(&port->xmit_fifo);
796 	struct sdio_uart_port *port = tty->driver_data;
798 	port->x_char = ch;
799 	if (ch && !(port->ier & UART_IER_THRI)) {
800 		if (sdio_uart_claim_func(port) != 0)
802 		sdio_uart_start_tx(port);
803 		sdio_uart_irq(port->func);
804 		sdio_uart_release_func(port);
810 	struct sdio_uart_port *port = tty->driver_data;
815 	if (sdio_uart_claim_func(port) != 0)
819 		port->x_char = STOP_CHAR(tty);
820 		sdio_uart_start_tx(port);
824 		sdio_uart_clear_mctrl(port, TIOCM_RTS);
826 	sdio_uart_irq(port->func);
827 	sdio_uart_release_func(port);
832 	struct sdio_uart_port *port = tty->driver_data;
837 	if (sdio_uart_claim_func(port) != 0)
841 		if (port->x_char) {
842 			port->x_char = 0;
844 			port->x_char = START_CHAR(tty);
845 			sdio_uart_start_tx(port);
850 		sdio_uart_set_mctrl(port, TIOCM_RTS);
852 	sdio_uart_irq(port->func);
853 	sdio_uart_release_func(port);
859 	struct sdio_uart_port *port = tty->driver_data;
862 	if (sdio_uart_claim_func(port) != 0)
865 	sdio_uart_change_speed(port, &tty->termios, old_termios);
869 		sdio_uart_clear_mctrl(port, TIOCM_RTS | TIOCM_DTR);
876 		sdio_uart_set_mctrl(port, mask);
882 		sdio_uart_start_tx(port);
887 		if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS)) {
889 			sdio_uart_stop_tx(port);
893 	sdio_uart_release_func(port);
898 	struct sdio_uart_port *port = tty->driver_data;
901 	result = sdio_uart_claim_func(port);
906 		port->lcr |= UART_LCR_SBC;
908 		port->lcr &= ~UART_LCR_SBC;
909 	sdio_out(port, UART_LCR, port->lcr);
911 	sdio_uart_release_func(port);
917 	struct sdio_uart_port *port = tty->driver_data;
920 	result = sdio_uart_claim_func(port);
922 		result = port->mctrl | sdio_uart_get_mctrl(port);
923 		sdio_uart_release_func(port);
932 	struct sdio_uart_port *port = tty->driver_data;
935 	result = sdio_uart_claim_func(port);
937 		sdio_uart_update_mctrl(port, set, clear);
938 		sdio_uart_release_func(port);
951 		struct sdio_uart_port *port = sdio_uart_port_get(i);
952 		if (port) {
956 					      port->icount.tx, port->icount.rx);
957 				if (port->icount.frame)
959 						      port->icount.frame);
960 				if (port->icount.parity)
962 						      port->icount.parity);
963 				if (port->icount.brk)
965 						      port->icount.brk);
966 				if (port->icount.overrun)
968 						      port->icount.overrun);
969 				if (port->icount.cts)
971 						      port->icount.cts);
972 				if (port->icount.dsr)
974 						      port->icount.dsr);
975 				if (port->icount.rng)
977 						      port->icount.rng);
978 				if (port->icount.dcd)
980 						      port->icount.dcd);
982 			sdio_uart_port_put(port);
1021 	struct sdio_uart_port *port;
1024 	port = kzalloc(sizeof(struct sdio_uart_port), GFP_KERNEL);
1025 	if (!port)
1031 		kfree(port);
1050 			kfree(port);
1055 		port->regs_offset = (tpl->data[4] << 0) |
1059 		       sdio_func_id(func), port->regs_offset);
1060 		port->uartclk = tpl->data[7] * 115200;
1061 		if (port->uartclk == 0)
1062 			port->uartclk = 115200;
1064 		       sdio_func_id(func), port->uartclk,
1067 		kfree(port);
1071 	port->func = func;
1072 	sdio_set_drvdata(func, port);
1073 	tty_port_init(&port->port);
1074 	port->port.ops = &sdio_uart_port_ops;
1076 	ret = sdio_uart_add_port(port);
1078 		kfree(port);
1081 		dev = tty_port_register_device(&port->port,
1082 				sdio_uart_tty_driver, port->index, &func->dev);
1084 			sdio_uart_port_remove(port);
1094 	struct sdio_uart_port *port = sdio_get_drvdata(func);
1096 	tty_unregister_device(sdio_uart_tty_driver, port->index);
1097 	sdio_uart_port_remove(port);