Skip to content

Commit

Permalink
serial8250: Add dl_read()/dl_write() callbacks
Browse files Browse the repository at this point in the history 
Convert serial_dl_read() and serial_dl_write() from macro
to 8250 specific callbacks. This change makes it easier to
support 8250 hardware with non-standard DLL and DLM register
configurations such as Alchemy, RM9K and upcoming Emma Mobile
UART hardware.

Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  • Loading branch information
Magnus Damm authored and Greg Kroah-Hartman committed May 2, 2012
1 parent f9a9111 commit cc419fa
Show file tree
Hide file tree
Showing 2 changed files with 78 additions and 53 deletions.
117 changes: 64 additions & 53 deletions drivers/tty/serial/8250/8250.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -284,6 +284,66 @@ static const struct serial8250_config uart_config[] = {
},
};

/* Uart divisor latch read */
static int default_dl_read(struct uart_8250_port *up)
{
return serial_in(up, UART_DLL) | serial_in(up, UART_DLM) << 8;
}

/* Uart divisor latch write */
static void default_dl_write(struct uart_8250_port *up, int value)
{
serial_out(up, UART_DLL, value & 0xff);
serial_out(up, UART_DLM, value >> 8 & 0xff);
}

#if defined(CONFIG_MIPS_ALCHEMY)
/* Au1x00 haven't got a standard divisor latch */
static int _serial_dl_read(struct uart_8250_port *up)
{
if (up->port.iotype == UPIO_AU)
return __raw_readl(up->port.membase + 0x28);
else
return default_dl_read(up);
}

static void _serial_dl_write(struct uart_8250_port *up, int value)
{
if (up->port.iotype == UPIO_AU)
__raw_writel(value, up->port.membase + 0x28);
else
default_dl_write(up, value);
}
#elif defined(CONFIG_SERIAL_8250_RM9K)
static int _serial_dl_read(struct uart_8250_port *up)
{
return (up->port.iotype == UPIO_RM9000) ?
(((__raw_readl(up->port.membase + 0x10) << 8) |
(__raw_readl(up->port.membase + 0x08) & 0xff)) & 0xffff) :
default_dl_read(up);
}

static void _serial_dl_write(struct uart_8250_port *up, int value)
{
if (up->port.iotype == UPIO_RM9000) {
__raw_writel(value, up->port.membase + 0x08);
__raw_writel(value >> 8, up->port.membase + 0x10);
} else {
default_dl_write(up, value);
}
}
#else
static int _serial_dl_read(struct uart_8250_port *up)
{
return default_dl_read(up);
}

static void _serial_dl_write(struct uart_8250_port *up, int value)
{
default_dl_write(up, value);
}
#endif

#if defined(CONFIG_MIPS_ALCHEMY)

/* Au1x00 UART hardware has a weird register layout */
Expand Down Expand Up @@ -434,6 +494,10 @@ static void set_io_from_upio(struct uart_port *p)
{
struct uart_8250_port *up =
container_of(p, struct uart_8250_port, port);

up->dl_read = _serial_dl_read;
up->dl_write = _serial_dl_write;

switch (p->iotype) {
case UPIO_HUB6:
p->serial_in = hub6_serial_in;
Expand Down Expand Up @@ -481,59 +545,6 @@ serial_port_out_sync(struct uart_port *p, int offset, int value)
}
}

/* Uart divisor latch read */
static inline int _serial_dl_read(struct uart_8250_port *up)
{
return serial_in(up, UART_DLL) | serial_in(up, UART_DLM) << 8;
}

/* Uart divisor latch write */
static inline void _serial_dl_write(struct uart_8250_port *up, int value)
{
serial_out(up, UART_DLL, value & 0xff);
serial_out(up, UART_DLM, value >> 8 & 0xff);
}

#if defined(CONFIG_MIPS_ALCHEMY)
/* Au1x00 haven't got a standard divisor latch */
static int serial_dl_read(struct uart_8250_port *up)
{
if (up->port.iotype == UPIO_AU)
return __raw_readl(up->port.membase + 0x28);
else
return _serial_dl_read(up);
}

static void serial_dl_write(struct uart_8250_port *up, int value)
{
if (up->port.iotype == UPIO_AU)
__raw_writel(value, up->port.membase + 0x28);
else
_serial_dl_write(up, value);
}
#elif defined(CONFIG_SERIAL_8250_RM9K)
static int serial_dl_read(struct uart_8250_port *up)
{
return (up->port.iotype == UPIO_RM9000) ?
(((__raw_readl(up->port.membase + 0x10) << 8) |
(__raw_readl(up->port.membase + 0x08) & 0xff)) & 0xffff) :
_serial_dl_read(up);
}

static void serial_dl_write(struct uart_8250_port *up, int value)
{
if (up->port.iotype == UPIO_RM9000) {
__raw_writel(value, up->port.membase + 0x08);
__raw_writel(value >> 8, up->port.membase + 0x10);
} else {
_serial_dl_write(up, value);
}
}
#else
#define serial_dl_read(up) _serial_dl_read(up)
#define serial_dl_write(up, value) _serial_dl_write(up, value)
#endif

/*
* For the 16C950
*/
Expand Down
14 changes: 14 additions & 0 deletions drivers/tty/serial/8250/8250.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -37,6 +37,10 @@ struct uart_8250_port {
unsigned char lsr_saved_flags;
#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
unsigned char msr_saved_flags;

/* 8250 specific callbacks */
int (*dl_read)(struct uart_8250_port *);
void (*dl_write)(struct uart_8250_port *, int);
};

struct old_serial_port {
Expand Down Expand Up @@ -98,6 +102,16 @@ static inline void serial_out(struct uart_8250_port *up, int offset, int value)

void serial8250_clear_and_reinit_fifos(struct uart_8250_port *p);

static inline int serial_dl_read(struct uart_8250_port *up)
{
return up->dl_read(up);
}

static inline void serial_dl_write(struct uart_8250_port *up, int value)
{
up->dl_write(up, value);
}

#if defined(__alpha__) && !defined(CONFIG_PCI)
/*
* Digital did something really horribly wrong with the OUT1 and OUT2
Expand Down

0 comments on commit cc419fa

Please sign in to comment.