From 235dae5d094c415fcf0fc79fa637f1901bc8afe2 Mon Sep 17 00:00:00 2001 From: Philippe Langlais Date: Thu, 29 Jul 2010 17:13:57 +0200 Subject: U6715 16550A serial driver support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit UART Features extract from STEricsson U6715 data-sheet (arm926 SoC for mobile phone): * Fully compatible with industry standard 16C550 and 16C450 from various manufacturers * RX and TX 64 byte FIFO reduces CPU interrupts * Full double buffering * Modem control signals include CTS, RTS, (and DSR, DTR on UART1 only) * Automatic baud rate selection * Manual or automatic RTS/CTS smart hardware flow control * Programmable serial characteristics: – Baud rate generation (50 to 3.25M baud) – 5, 6, 7 or 8-bit characters – Even, odd or no-parity bit generation and detection – 1, 1.5 or 2 stop bit generation * Independent control of transmit, receive, line status, data set interrupts and FIFOs * Full status-reporting capabilities * Separate DMA signaling for RX and TX * Timed interrupt to spread receive interrupt on known duration * DMA time-out interrupt to allow detection of end of reception * Carkit pulse coding and decoding compliant with USB carkit control interface [40] In 16550A auto-configuration, if the fifo size is 64 then it's an U6 16550A port Add set_termios hook & export serial8250_do_set_termios to change uart clock following baudrate Signed-off-by: Philippe Langlais Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/serial/8250.c | 37 ++++++++++++++++++++++++++++++++++--- 1 file changed, 34 insertions(+), 3 deletions(-) (limited to 'drivers/serial') diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index 355148dc085e..24110f6f61e0 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -300,6 +300,13 @@ static const struct serial8250_config uart_config[] = { .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_00, .flags = UART_CAP_FIFO | UART_CAP_AFE, }, + [PORT_U6_16550A] = { + .name = "U6_16550A", + .fifo_size = 64, + .tx_loadsz = 64, + .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10, + .flags = UART_CAP_FIFO | UART_CAP_AFE, + }, }; #if defined(CONFIG_MIPS_ALCHEMY) @@ -1070,6 +1077,15 @@ static void autoconfig_16550a(struct uart_8250_port *up) DEBUG_AUTOCONF("Couldn't force IER_UUE to 0 "); } serial_outp(up, UART_IER, iersave); + + /* + * We distinguish between 16550A and U6 16550A by counting + * how many bytes are in the FIFO. + */ + if (up->port.type == PORT_16550A && size_fifo(up) == 64) { + up->port.type = PORT_U6_16550A; + up->capabilities |= UART_CAP_AFE; + } } /* @@ -2224,9 +2240,9 @@ static unsigned int serial8250_get_divisor(struct uart_port *port, unsigned int return quot; } -static void -serial8250_set_termios(struct uart_port *port, struct ktermios *termios, - struct ktermios *old) +void +serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) { struct uart_8250_port *up = (struct uart_8250_port *)port; unsigned char cval, fcr = 0; @@ -2402,6 +2418,17 @@ serial8250_set_termios(struct uart_port *port, struct ktermios *termios, if (tty_termios_baud_rate(termios)) tty_termios_encode_baud_rate(termios, baud, baud); } +EXPORT_SYMBOL(serial8250_do_set_termios); + +static void +serial8250_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) +{ + if (port->set_termios) + port->set_termios(port, termios, old); + else + serial8250_do_set_termios(port, termios, old); +} static void serial8250_set_ldisc(struct uart_port *port, int new) @@ -2982,6 +3009,7 @@ static int __devinit serial8250_probe(struct platform_device *dev) port.type = p->type; port.serial_in = p->serial_in; port.serial_out = p->serial_out; + port.set_termios = p->set_termios; port.dev = &dev->dev; port.irqflags |= irqflag; ret = serial8250_register_port(&port); @@ -3145,6 +3173,9 @@ int serial8250_register_port(struct uart_port *port) uart->port.serial_in = port->serial_in; if (port->serial_out) uart->port.serial_out = port->serial_out; + /* Possibly override set_termios call */ + if (port->set_termios) + uart->port.set_termios = port->set_termios; ret = uart_add_one_port(&serial8250_reg, &uart->port); if (ret == 0) -- cgit v1.2.2