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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>
This commit is contained in:
Philippe Langlais 2010-07-29 17:13:57 +02:00 committed by Greg Kroah-Hartman
parent bf9c1fca9a
commit 235dae5d09
4 changed files with 44 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
drivers/serial/8250.c
View File

@ -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;
}
}
/*
@ -2224,8 +2240,8 @@ 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,
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;
@ -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)

3
include/linux/serial.h
View File

@ -77,7 +77,8 @@ struct serial_struct {
#define PORT_16654 11
#define PORT_16850 12
#define PORT_RSA 13 /* RSA-DV II/S card */
#define PORT_MAX 13
#define PORT_U6_16550A 14
#define PORT_MAX 14
#define SERIAL_IO_PORT 0
#define SERIAL_IO_HUB6 1

5
include/linux/serial_8250.h
View File

@ -32,6 +32,9 @@ struct plat_serial8250_port {
unsigned int type; /* If UPF_FIXED_TYPE */
unsigned int (*serial_in)(struct uart_port *, int);
void (*serial_out)(struct uart_port *, int, int);
void (*set_termios)(struct uart_port *,
struct ktermios *new,
struct ktermios *old);
};
/*
@ -71,5 +74,7 @@ extern int early_serial_setup(struct uart_port *port);
extern int serial8250_find_port(struct uart_port *p);
extern int serial8250_find_port_for_earlycon(void);
extern int setup_early_serial8250_console(char *cmdline);
extern void serial8250_do_set_termios(struct uart_port *port,
struct ktermios *termios, struct ktermios *old);
#endif

3
include/linux/serial_core.h
View File

@ -282,6 +282,9 @@ struct uart_port {
unsigned char __iomem *membase; /* read/write[bwl] */
unsigned int (*serial_in)(struct uart_port *, int);
void (*serial_out)(struct uart_port *, int, int);
void (*set_termios)(struct uart_port *,
struct ktermios *new,
struct ktermios *old);
unsigned int irq; /* irq number */
unsigned long irqflags; /* irq flags */
unsigned int uartclk; /* base uart clock */