Commit 235dae5d authored by Philippe Langlais's avatar Philippe Langlais Committed by Greg Kroah-Hartman
Browse files

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: default avatarPhilippe Langlais <philippe.langlais@stericsson.com>
Acked-by: default avatarAlan Cox <alan@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent bf9c1fca

drivers/serial/8250.c

+34 −3
Original line number Diff line number Diff line
@@ -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)

include/linux/serial.h

+2 −1
Original line number Diff line number Diff line
@@ -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

include/linux/serial_8250.h

+5 −0
Original line number Diff line number Diff line
@@ -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

include/linux/serial_core.h

+3 −0
Original line number Diff line number Diff line
@@ -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 */

CRA Git | Maintained and supported by SUSTech CRA and CCSE