[PATCH 01/06] serial8250: Add dl_read()/dl_write() callbacks

From: Magnus Damm
Date: Wed May 02 2012 - 08:46:07 EST


From: Magnus Damm <damm@xxxxxxxxxxxxx>

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@xxxxxxxxxxxxx>
---

drivers/tty/serial/8250/8250.c | 117 +++++++++++++++++++++-------------------
drivers/tty/serial/8250/8250.h | 14 ++++
2 files changed, 78 insertions(+), 53 deletions(-)

--- 0001/drivers/tty/serial/8250/8250.c
+++ work/drivers/tty/serial/8250/8250.c 2012-05-01 22:50:38.000000000 +0900
@@ -284,6 +284,66 @@ static const struct serial8250_config ua
},
};

+/* 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 */
@@ -434,6 +494,10 @@ static void set_io_from_upio(struct uart
{
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;
@@ -481,59 +545,6 @@ serial_port_out_sync(struct uart_port *p
}
}

-/* 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
*/
--- 0001/drivers/tty/serial/8250/8250.h
+++ work/drivers/tty/serial/8250/8250.h 2012-05-01 22:50:38.000000000 +0900
@@ -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 {
@@ -96,6 +100,16 @@ static inline void serial_out(struct uar
up->port.serial_out(&up->port, offset, value);
}

+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
--
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