Skip to content

Commit

Permalink
altera_uart: Add support for different address strides
Browse files Browse the repository at this point in the history 
Some controllers implement registers with a stride, to support
those we must implement the proper IO accessors.

Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Acked-by: Tobias Klauser <tklauser@distanz.ch>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
  • Loading branch information
Anton Vorontsov authored and Greg Kroah-Hartman committed Oct 22, 2010
1 parent 6b5756f commit 0d426ed
Show file tree
Hide file tree
Showing 2 changed files with 38 additions and 21 deletions.
58 changes: 37 additions & 21 deletions drivers/serial/altera_uart.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -82,9 +82,23 @@ struct altera_uart {
unsigned short imr; /* Local IMR mirror */
};

static u32 altera_uart_readl(struct uart_port *port, int reg)
{
struct altera_uart_platform_uart *platp = port->private_data;

return readl(port->membase + (reg << platp->bus_shift));
}

static void altera_uart_writel(struct uart_port *port, u32 dat, int reg)
{
struct altera_uart_platform_uart *platp = port->private_data;

writel(dat, port->membase + (reg << platp->bus_shift));
}

static unsigned int altera_uart_tx_empty(struct uart_port *port)
{
return (readl(port->membase + ALTERA_UART_STATUS_REG) &
return (altera_uart_readl(port, ALTERA_UART_STATUS_REG) &
ALTERA_UART_STATUS_TMT_MSK) ? TIOCSER_TEMT : 0;
}

Expand All @@ -93,8 +107,7 @@ static unsigned int altera_uart_get_mctrl(struct uart_port *port)
struct altera_uart *pp = container_of(port, struct altera_uart, port);
unsigned int sigs;

sigs =
(readl(port->membase + ALTERA_UART_STATUS_REG) &
sigs = (altera_uart_readl(port, ALTERA_UART_STATUS_REG) &
ALTERA_UART_STATUS_CTS_MSK) ? TIOCM_CTS : 0;
sigs |= (pp->sigs & TIOCM_RTS);

Expand All @@ -110,31 +123,31 @@ static void altera_uart_set_mctrl(struct uart_port *port, unsigned int sigs)
pp->imr |= ALTERA_UART_CONTROL_RTS_MSK;
else
pp->imr &= ~ALTERA_UART_CONTROL_RTS_MSK;
writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
altera_uart_writel(port, pp->imr, ALTERA_UART_CONTROL_REG);
}

static void altera_uart_start_tx(struct uart_port *port)
{
struct altera_uart *pp = container_of(port, struct altera_uart, port);

pp->imr |= ALTERA_UART_CONTROL_TRDY_MSK;
writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
altera_uart_writel(port, pp->imr, ALTERA_UART_CONTROL_REG);
}

static void altera_uart_stop_tx(struct uart_port *port)
{
struct altera_uart *pp = container_of(port, struct altera_uart, port);

pp->imr &= ~ALTERA_UART_CONTROL_TRDY_MSK;
writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
altera_uart_writel(port, pp->imr, ALTERA_UART_CONTROL_REG);
}

static void altera_uart_stop_rx(struct uart_port *port)
{
struct altera_uart *pp = container_of(port, struct altera_uart, port);

pp->imr &= ~ALTERA_UART_CONTROL_RRDY_MSK;
writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
altera_uart_writel(port, pp->imr, ALTERA_UART_CONTROL_REG);
}

static void altera_uart_break_ctl(struct uart_port *port, int break_state)
Expand All @@ -147,7 +160,7 @@ static void altera_uart_break_ctl(struct uart_port *port, int break_state)
pp->imr |= ALTERA_UART_CONTROL_TRBK_MSK;
else
pp->imr &= ~ALTERA_UART_CONTROL_TRBK_MSK;
writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
altera_uart_writel(port, pp->imr, ALTERA_UART_CONTROL_REG);
spin_unlock_irqrestore(&port->lock, flags);
}

Expand All @@ -171,7 +184,7 @@ static void altera_uart_set_termios(struct uart_port *port,

spin_lock_irqsave(&port->lock, flags);
uart_update_timeout(port, termios->c_cflag, baud);
writel(baudclk, port->membase + ALTERA_UART_DIVISOR_REG);
altera_uart_writel(port, baudclk, ALTERA_UART_DIVISOR_REG);
spin_unlock_irqrestore(&port->lock, flags);
}

Expand All @@ -181,14 +194,15 @@ static void altera_uart_rx_chars(struct altera_uart *pp)
unsigned char ch, flag;
unsigned short status;

while ((status = readl(port->membase + ALTERA_UART_STATUS_REG)) &
while ((status = altera_uart_readl(port, ALTERA_UART_STATUS_REG)) &
ALTERA_UART_STATUS_RRDY_MSK) {
ch = readl(port->membase + ALTERA_UART_RXDATA_REG);
ch = altera_uart_readl(port, ALTERA_UART_RXDATA_REG);
flag = TTY_NORMAL;
port->icount.rx++;

if (status & ALTERA_UART_STATUS_E_MSK) {
writel(status, port->membase + ALTERA_UART_STATUS_REG);
altera_uart_writel(port, status,
ALTERA_UART_STATUS_REG);

if (status & ALTERA_UART_STATUS_BRK_MSK) {
port->icount.brk++;
Expand Down Expand Up @@ -228,18 +242,18 @@ static void altera_uart_tx_chars(struct altera_uart *pp)

if (port->x_char) {
/* Send special char - probably flow control */
writel(port->x_char, port->membase + ALTERA_UART_TXDATA_REG);
altera_uart_writel(port, port->x_char, ALTERA_UART_TXDATA_REG);
port->x_char = 0;
port->icount.tx++;
return;
}

while (readl(port->membase + ALTERA_UART_STATUS_REG) &
while (altera_uart_readl(port, ALTERA_UART_STATUS_REG) &
ALTERA_UART_STATUS_TRDY_MSK) {
if (xmit->head == xmit->tail)
break;
writel(xmit->buf[xmit->tail],
port->membase + ALTERA_UART_TXDATA_REG);
altera_uart_writel(port, xmit->buf[xmit->tail],
ALTERA_UART_TXDATA_REG);
xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
port->icount.tx++;
}
Expand All @@ -249,7 +263,7 @@ static void altera_uart_tx_chars(struct altera_uart *pp)

if (xmit->head == xmit->tail) {
pp->imr &= ~ALTERA_UART_CONTROL_TRDY_MSK;
writel(pp->imr, port->membase + ALTERA_UART_CONTROL_REG);
altera_uart_writel(port, pp->imr, ALTERA_UART_CONTROL_REG);
}
}

Expand All @@ -259,7 +273,7 @@ static irqreturn_t altera_uart_interrupt(int irq, void *data)
struct altera_uart *pp = container_of(port, struct altera_uart, port);
unsigned int isr;

isr = readl(port->membase + ALTERA_UART_STATUS_REG) & pp->imr;
isr = altera_uart_readl(port, ALTERA_UART_STATUS_REG) & pp->imr;

spin_lock(&port->lock);
if (isr & ALTERA_UART_STATUS_RRDY_MSK)
Expand All @@ -285,9 +299,9 @@ static void altera_uart_config_port(struct uart_port *port, int flags)
port->type = PORT_ALTERA_UART;

/* Clear mask, so no surprise interrupts. */
writel(0, port->membase + ALTERA_UART_CONTROL_REG);
altera_uart_writel(port, 0, ALTERA_UART_CONTROL_REG);
/* Clear status register */
writel(0, port->membase + ALTERA_UART_STATUS_REG);
altera_uart_writel(port, 0, ALTERA_UART_STATUS_REG);
}

static int altera_uart_startup(struct uart_port *port)
Expand Down Expand Up @@ -407,14 +421,15 @@ int __init early_altera_uart_setup(struct altera_uart_platform_uart *platp)
port->uartclk = platp[i].uartclk;
port->flags = ASYNC_BOOT_AUTOCONF;
port->ops = &altera_uart_ops;
port->private_data = platp;
}

return 0;
}

static void altera_uart_console_putc(struct uart_port *port, const char c)
{
while (!(readl(port->membase + ALTERA_UART_STATUS_REG) &
while (!(altera_uart_readl(port, ALTERA_UART_STATUS_REG) &
ALTERA_UART_STATUS_TRDY_MSK))
cpu_relax();

Expand Down Expand Up @@ -535,6 +550,7 @@ static int __devinit altera_uart_probe(struct platform_device *pdev)
port->uartclk = platp->uartclk;
port->ops = &altera_uart_ops;
port->flags = ASYNC_BOOT_AUTOCONF;
port->private_data = platp;

uart_add_one_port(&altera_uart_driver, port);

Expand Down
1 change: 1 addition & 0 deletions include/linux/altera_uart.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@ struct altera_uart_platform_uart {
unsigned long mapbase; /* Physical address base */
unsigned int irq; /* Interrupt vector */
unsigned int uartclk; /* UART clock rate */
unsigned int bus_shift; /* Bus shift (address stride) */
};

#endif /* __ALTUART_H */

0 comments on commit 0d426ed

Please sign in to comment.