diff options
| author | Lech Perczak <l.perczak@camlintechnologies.com> | 2022-02-21 11:56:13 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-02-25 10:24:27 +0100 |
| commit | c112653b89e0cea4aa2ea26fcfbbb30a2193339e (patch) | |
| tree | e24b54727a9a59274efb3ce8d1cc16dbe63bccd9 /drivers/tty/serial/sc16is7xx.c | |
| parent | serial: 8250: Return early in .start_tx() if there are no chars to send (diff) | |
| download | linux-c112653b89e0cea4aa2ea26fcfbbb30a2193339e.tar.xz linux-c112653b89e0cea4aa2ea26fcfbbb30a2193339e.zip | |
sc16is7xx: Preserve EFR bits on update
Preserve unaffected bits state when accessing EFR register. This
prevents hardware flow control bits from being cleared on enhanced
functions access.
Signed-off-by: Lech Perczak <l.perczak@camlintechnologies.com>
Signed-off-by: Tomasz Moń <tomasz.mon@camlingroup.com>
Link: https://lore.kernel.org/r/20220221105618.3503470-2-tomasz.mon@camlingroup.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/sc16is7xx.c')
| -rw-r--r-- | drivers/tty/serial/sc16is7xx.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index 64e7e6c8145f..3a808b2cae4f 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -289,6 +289,14 @@ * XON1, XON2, XOFF1 and * XOFF2 */ +#define SC16IS7XX_EFR_FLOWCTRL_BITS (SC16IS7XX_EFR_AUTORTS_BIT | \ + SC16IS7XX_EFR_AUTOCTS_BIT | \ + SC16IS7XX_EFR_XOFF2_DETECT_BIT | \ + SC16IS7XX_EFR_SWFLOW3_BIT | \ + SC16IS7XX_EFR_SWFLOW2_BIT | \ + SC16IS7XX_EFR_SWFLOW1_BIT | \ + SC16IS7XX_EFR_SWFLOW0_BIT) + /* Misc definitions */ #define SC16IS7XX_FIFO_SIZE (64) @@ -523,8 +531,10 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) /* Enable enhanced features */ regcache_cache_bypass(s->regmap, true); - sc16is7xx_port_write(port, SC16IS7XX_EFR_REG, - SC16IS7XX_EFR_ENABLE_BIT); + sc16is7xx_port_update(port, SC16IS7XX_EFR_REG, + SC16IS7XX_EFR_ENABLE_BIT, + SC16IS7XX_EFR_ENABLE_BIT); + regcache_cache_bypass(s->regmap, false); /* Put LCR back to the normal mode */ @@ -932,7 +942,10 @@ static void sc16is7xx_set_termios(struct uart_port *port, if (termios->c_iflag & IXOFF) flow |= SC16IS7XX_EFR_SWFLOW1_BIT; - sc16is7xx_port_write(port, SC16IS7XX_EFR_REG, flow); + sc16is7xx_port_update(port, + SC16IS7XX_EFR_REG, + SC16IS7XX_EFR_FLOWCTRL_BITS, + flow); regcache_cache_bypass(s->regmap, false); /* Update LCR register */ @@ -1007,8 +1020,9 @@ static int sc16is7xx_startup(struct uart_port *port) regcache_cache_bypass(s->regmap, true); /* Enable write access to enhanced features and internal clock div */ - sc16is7xx_port_write(port, SC16IS7XX_EFR_REG, - SC16IS7XX_EFR_ENABLE_BIT); + sc16is7xx_port_update(port, SC16IS7XX_EFR_REG, + SC16IS7XX_EFR_ENABLE_BIT, + SC16IS7XX_EFR_ENABLE_BIT); /* Enable TCR/TLR */ sc16is7xx_port_update(port, SC16IS7XX_MCR_REG, |