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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: Andrey 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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Andrey Smirnov 2019-07-29 12:52:11 -07:00 committed by Greg Kroah-Hartman
parent 15dd287b28
commit 93b9523a8e
1 changed files with 35 additions and 26 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

61
drivers/tty/serial/fsl_lpuart.c
View File

@ -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:
lpuart_transmit_buffer(sport);
spin_unlock_irqrestore(&sport->port.lock, flags);
}
@ -876,6 +876,15 @@ static void lpuart_rxint(struct lpuart_port *sport)
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;