Commit e302cd93 authored by Emilio López's avatar Emilio López Committed by Greg Kroah-Hartman

serial: 8250_dw: add support for clk api

This commit implements support for using the clk api; this lets us use
the "clocks" property with device tree, instead of having to use
clock-frequency.
Signed-off-by: default avatarEmilio López <emilio@elopez.com.ar>
Signed-off-by: default avatarMaxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 38adbc54
......@@ -26,6 +26,7 @@
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/acpi.h>
#include <linux/clk.h>
#include "8250.h"
......@@ -57,6 +58,7 @@
struct dw8250_data {
int last_lcr;
int line;
struct clk *clk;
};
static void dw8250_serial_out(struct uart_port *p, int offset, int value)
......@@ -136,8 +138,13 @@ static int dw8250_probe_of(struct uart_port *p)
if (!of_property_read_u32(np, "reg-shift", &val))
p->regshift = val;
/* clock got configured through clk api, all done */
if (p->uartclk)
return 0;
/* try to find out clock frequency from DT as fallback */
if (of_property_read_u32(np, "clock-frequency", &val)) {
dev_err(p->dev, "no clock-frequency property set\n");
dev_err(p->dev, "clk or clock-frequency not defined\n");
return -EINVAL;
}
p->uartclk = val;
......@@ -294,9 +301,20 @@ static int dw8250_probe(struct platform_device *pdev)
if (!uart.port.membase)
return -ENOMEM;
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->clk = devm_clk_get(&pdev->dev, NULL);
if (!IS_ERR(data->clk)) {
clk_prepare_enable(data->clk);
uart.port.uartclk = clk_get_rate(data->clk);
}
uart.port.iotype = UPIO_MEM;
uart.port.serial_in = dw8250_serial_in;
uart.port.serial_out = dw8250_serial_out;
uart.port.private_data = data;
dw8250_setup_port(&uart);
......@@ -312,12 +330,6 @@ static int dw8250_probe(struct platform_device *pdev)
return -ENODEV;
}
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
uart.port.private_data = data;
data->line = serial8250_register_8250_port(&uart);
if (data->line < 0)
return data->line;
......@@ -333,6 +345,9 @@ static int dw8250_remove(struct platform_device *pdev)
serial8250_unregister_port(data->line);
if (!IS_ERR(data->clk))
clk_disable_unprepare(data->clk);
return 0;
}
......
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