U6715 16550A serial driver support
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 <philippe.langlais@stericsson.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 355148d..24110f6 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -300,6 +300,13 @@
.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 @@
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 @@
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 @@
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 @@
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 @@
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)