Commit 93b9523a authored by Andrey Smirnov's avatar Andrey Smirnov Committed by Greg Kroah-Hartman
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tty: serial: fls_lpuart: Split shared TX IRQ handler into two 



While sharing code for Tx interrupt handler between 8 and 32 bit
variant of the peripheral saves a bit of code duplication it also adds
quite a number of lpuart_is_32() checks which makes it harder to
understand. Move shared bits back into corresponding
lpuart*_transmit_buffer functions, split lpuart_txint into
lpuart_txint and lpuart32_txint so we can drop all extra
lpuart_is_32() check and make the code flow more linear.

Signed-off-by: default avatarAndrey Smirnov <andrew.smirnov@gmail.com>
Cc: Stefan Agner <stefan@agner.ch>
Cc: Bhuvanchandra DV <bhuvanchandra.dv@toradex.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Cory Tusar <cory.tusar@zii.aero>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: linux-imx@nxp.com
Cc: linux-serial@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/20190729195226.8862-10-andrew.smirnov@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 15dd287b

drivers/tty/serial/fsl_lpuart.c

+35 −26
Original line number Diff line number Diff line
@@ -663,6 +663,18 @@ static inline void lpuart_transmit_buffer(struct lpuart_port *sport) 
{

	struct circ_buf *xmit = &sport->port.state->xmit;



	if (sport->port.x_char) {

		writeb(sport->port.x_char, sport->port.membase + UARTDR);

		sport->port.icount.tx++;

		sport->port.x_char = 0;

		return;

	}



	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {

		lpuart_stop_tx(&sport->port);

		return;

	}



	while (!uart_circ_empty(xmit) &&

		(readb(sport->port.membase + UARTTCFIFO) < sport->txfifo_size)) {

		writeb(xmit->buf[xmit->tail], sport->port.membase + UARTDR);
@@ -682,6 +694,18 @@ static inline void lpuart32_transmit_buffer(struct lpuart_port *sport) 
	struct circ_buf *xmit = &sport->port.state->xmit;

	unsigned long txcnt;



	if (sport->port.x_char) {

		lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);

		sport->port.icount.tx++;

		sport->port.x_char = 0;

		return;

	}



	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {

		lpuart32_stop_tx(&sport->port);

		return;

	}



	txcnt = lpuart32_read(&sport->port, UARTWATER);

	txcnt = txcnt >> UARTWATER_TXCNT_OFF;

	txcnt &= UARTWATER_COUNT_MASK;
@@ -773,34 +797,10 @@ static unsigned int lpuart32_tx_empty(struct uart_port *port) 


static void lpuart_txint(struct lpuart_port *sport)

{

	struct circ_buf *xmit = &sport->port.state->xmit;

	unsigned long flags;



	spin_lock_irqsave(&sport->port.lock, flags);

	if (sport->port.x_char) {

		if (lpuart_is_32(sport))

			lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);

		else

			writeb(sport->port.x_char, sport->port.membase + UARTDR);

		sport->port.icount.tx++;

		sport->port.x_char = 0;

		goto out;

	}



	if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {

		if (lpuart_is_32(sport))

			lpuart32_stop_tx(&sport->port);

		else

			lpuart_stop_tx(&sport->port);

		goto out;

	}



	if (lpuart_is_32(sport))

		lpuart32_transmit_buffer(sport);

	else

	lpuart_transmit_buffer(sport);



out:

	spin_unlock_irqrestore(&sport->port.lock, flags);

}
@@ -876,6 +876,15 @@ out: 
	tty_flip_buffer_push(port);

}



static void lpuart32_txint(struct lpuart_port *sport)

{

	unsigned long flags;



	spin_lock_irqsave(&sport->port.lock, flags);

	lpuart32_transmit_buffer(sport);

	spin_unlock_irqrestore(&sport->port.lock, flags);

}



static void lpuart32_rxint(struct lpuart_port *sport)

{

	unsigned int flg, ignored = 0;
@@ -967,7 +976,7 @@ static irqreturn_t lpuart32_int(int irq, void *dev_id) 
		lpuart32_rxint(sport);



	if ((sts & UARTSTAT_TDRE) && !sport->lpuart_dma_tx_use)

		lpuart_txint(sport);

		lpuart32_txint(sport);



	lpuart32_write(&sport->port, sts, UARTSTAT);

	return IRQ_HANDLED;

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