Commit 4ae82e5d authored by Jakub Kicinski's avatar Jakub Kicinski Committed by Greg Kroah-Hartman

sc16is7xx: use LSR_TEMT_BIT in .tx_empty()

LSR_TEMT_BIT (LSR bit 6) provides us exactly the information
we need to determine if transmission is finished - FIFO level
and shift register empty.  We can save ourselves reading FIFO
level explicitly if we use this bit.
Signed-off-by: default avatarJakub Kicinski <kubakici@wp.pl>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 4117a60c
...@@ -683,12 +683,11 @@ static void sc16is7xx_start_tx(struct uart_port *port) ...@@ -683,12 +683,11 @@ static void sc16is7xx_start_tx(struct uart_port *port)
static unsigned int sc16is7xx_tx_empty(struct uart_port *port) static unsigned int sc16is7xx_tx_empty(struct uart_port *port)
{ {
unsigned int lvl, lsr; unsigned int lsr;
lvl = sc16is7xx_port_read(port, SC16IS7XX_TXLVL_REG);
lsr = sc16is7xx_port_read(port, SC16IS7XX_LSR_REG); lsr = sc16is7xx_port_read(port, SC16IS7XX_LSR_REG);
return ((lsr & SC16IS7XX_LSR_THRE_BIT) && !lvl) ? TIOCSER_TEMT : 0; return (lsr & SC16IS7XX_LSR_TEMT_BIT) ? TIOCSER_TEMT : 0;
} }
static unsigned int sc16is7xx_get_mctrl(struct uart_port *port) static unsigned int sc16is7xx_get_mctrl(struct uart_port *port)
......
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