diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_port.c')
-rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 36 |
1 files changed, 35 insertions, 1 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 1328c7e70108..95833cbc4338 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -47,6 +47,10 @@ #define UART_EXAR_SLEEP 0x8b /* Sleep mode */ #define UART_EXAR_DVID 0x8d /* Device identification */ +/* Nuvoton NPCM timeout register */ +#define UART_NPCM_TOR 7 +#define UART_NPCM_TOIE BIT(7) /* Timeout Interrupt Enable */ + /* * Debugging. */ @@ -293,6 +297,15 @@ static const struct serial8250_config uart_config[] = { UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT, .flags = UART_CAP_FIFO, }, + [PORT_NPCM] = { + .name = "Nuvoton 16550", + .fifo_size = 16, + .tx_loadsz = 16, + .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10 | + UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT, + .rxtrig_bytes = {1, 4, 8, 14}, + .flags = UART_CAP_FIFO, + }, }; /* Uart divisor latch read */ @@ -1854,7 +1867,8 @@ int serial8250_handle_irq(struct uart_port *port, unsigned int iir) status = serial_port_in(port, UART_LSR); - if (status & (UART_LSR_DR | UART_LSR_BI)) { + if (status & (UART_LSR_DR | UART_LSR_BI) && + iir & UART_IIR_RDI) { if (!up->dma || handle_rx_dma(up, iir)) status = serial8250_rx_chars(up, status); } @@ -2140,6 +2154,15 @@ int serial8250_do_startup(struct uart_port *port) UART_DA830_PWREMU_MGMT_FREE); } + if (port->type == PORT_NPCM) { + /* + * Nuvoton calls the scratch register 'UART_TOR' (timeout + * register). Enable it, and set TIOC (timeout interrupt + * comparator) to be 0x20 for correct operation. + */ + serial_port_out(port, UART_NPCM_TOR, UART_NPCM_TOIE | 0x20); + } + #ifdef CONFIG_SERIAL_8250_RSA /* * If this is an RSA port, see if we can kick it up to the @@ -2462,6 +2485,15 @@ static unsigned int xr17v35x_get_divisor(struct uart_8250_port *up, return quot_16 >> 4; } +/* Nuvoton NPCM UARTs have a custom divisor calculation */ +static unsigned int npcm_get_divisor(struct uart_8250_port *up, + unsigned int baud) +{ + struct uart_port *port = &up->port; + + return DIV_ROUND_CLOSEST(port->uartclk, 16 * baud + 2) - 2; +} + static unsigned int serial8250_get_divisor(struct uart_8250_port *up, unsigned int baud, unsigned int *frac) @@ -2482,6 +2514,8 @@ static unsigned int serial8250_get_divisor(struct uart_8250_port *up, quot = 0x8002; else if (up->port.type == PORT_XR17V35X) quot = xr17v35x_get_divisor(up, baud, frac); + else if (up->port.type == PORT_NPCM) + quot = npcm_get_divisor(up, baud); else quot = uart_get_divisor(port, baud); |