cpm_uart: Add generic clock API support to set baudrates

This patch introduces baudrate setting support via the generic clock API.
When present the optional device tree clock property is used instead of
fsl-cpm-brg. Platforms can then define complex clock schemes, to output
the serial clock on an external pin for instance.

Signed-off-by: Laurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This commit is contained in:
Laurent Pinchart 2008-07-28 10:42:16 +02:00 committed by Kumar Gala
parent 7485d26b7e
commit 80776554b6
3 changed files with 21 additions and 7 deletions

View file

@ -283,6 +283,7 @@ config FSL_ULI1575
config CPM
bool
select PPC_CLOCK
config OF_RTC
bool

View file

@ -77,6 +77,7 @@ struct uart_cpm_port {
unsigned char *rx_buf;
u32 flags;
void (*set_lineif)(struct uart_cpm_port *);
struct clk *clk;
u8 brg;
uint dp_addr;
void *mem_addr;

View file

@ -45,6 +45,7 @@
#include <linux/of_platform.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
#include <linux/clk.h>
#include <asm/io.h>
#include <asm/irq.h>
@ -596,7 +597,10 @@ static void cpm_uart_set_termios(struct uart_port *port,
out_be16(&sccp->scc_psmr, (sbits << 12) | scval);
}
cpm_set_brg(pinfo->brg - 1, baud);
if (pinfo->clk)
clk_set_rate(pinfo->clk, baud);
else
cpm_set_brg(pinfo->brg - 1, baud);
spin_unlock_irqrestore(&port->lock, flags);
}
@ -1023,13 +1027,21 @@ static int cpm_uart_init_port(struct device_node *np,
int ret;
int i;
data = of_get_property(np, "fsl,cpm-brg", &len);
if (!data || len != 4) {
printk(KERN_ERR "CPM UART %s has no/invalid "
"fsl,cpm-brg property.\n", np->name);
return -EINVAL;
data = of_get_property(np, "clock", NULL);
if (data) {
struct clk *clk = clk_get(NULL, (const char*)data);
if (!IS_ERR(clk))
pinfo->clk = clk;
}
if (!pinfo->clk) {
data = of_get_property(np, "fsl,cpm-brg", &len);
if (!data || len != 4) {
printk(KERN_ERR "CPM UART %s has no/invalid "
"fsl,cpm-brg property.\n", np->name);
return -EINVAL;
}
pinfo->brg = *data;
}
pinfo->brg = *data;
data = of_get_property(np, "fsl,cpm-command", &len);
if (!data || len != 4) {