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serial: mxs-auart: Allow device tree probing

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Allow device tree probing.

Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Alan Cox <alan@linux.intel.com>
Cc: <linux-serial@vger.kernel.org>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Subodh Nijsure <snijsure@grid-net.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
This commit is contained in:
Fabio Estevam 2012-06-18 10:06:09 -03:00 committed by Shawn Guo
parent a217c46c2e
commit 1ea6607d4c
2 changed files with 67 additions and 2 deletions
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27
Documentation/devicetree/bindings/tty/serial/fsl-mxs-auart.txt Normal file
View file

@ -0,0 +1,27 @@
* Freescale MXS Application UART (AUART)
Required properties:
- compatible : Should be "fsl,<soc>-auart". The supported SoCs include
imx23 and imx28.
- reg : Address and length of the register set for the device
- interrupts : Should contain the auart interrupt numbers
Example:
auart0: serial@8006a000 {
compatible = "fsl,imx28-auart", "fsl,imx23-auart";
reg = <0x8006a000 0x2000>;
interrupts = <112 70 71>;
};
Note: Each auart port should have an alias correctly numbered in "aliases"
node.
Example:
aliases {
serial0 = &auart0;
serial1 = &auart1;
serial2 = &auart2;
serial3 = &auart3;
serial4 = &auart4;
};

42
drivers/tty/serial/mxs-auart.c
View file

@ -33,6 +33,7 @@
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/pinctrl/consumer.h>
#include <linux/of_device.h>
#include <asm/cacheflush.h>
@ -675,6 +676,30 @@ static struct uart_driver auart_driver = {
#endif
};
/*
* This function returns 1 if pdev isn't a device instatiated by dt, 0 if it
* could successfully get all information from dt or a negative errno.
*/
static int serial_mxs_probe_dt(struct mxs_auart_port *s,
struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
int ret;
if (!np)
/* no device tree device */
return 1;
ret = of_alias_get_id(np, "serial");
if (ret < 0) {
dev_err(&pdev->dev, "failed to get alias id: %d\n", ret);
return ret;
}
s->port.line = ret;
return 0;
}
static int __devinit mxs_auart_probe(struct platform_device *pdev)
{
struct mxs_auart_port *s;
@ -689,6 +714,12 @@ static int __devinit mxs_auart_probe(struct platform_device *pdev)
goto out;
}
ret = serial_mxs_probe_dt(s, pdev);
if (ret > 0)
s->port.line = pdev->id < 0 ? 0 : pdev->id;
else if (ret < 0)
goto out_free;
pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
if (IS_ERR(pinctrl)) {
ret = PTR_ERR(pinctrl);
@ -711,7 +742,6 @@ static int __devinit mxs_auart_probe(struct platform_device *pdev)
s->port.membase = ioremap(r->start, resource_size(r));
s->port.ops = &mxs_auart_ops;
s->port.iotype = UPIO_MEM;
s->port.line = pdev->id < 0 ? 0 : pdev->id;
s->port.fifosize = 16;
s->port.uartclk = clk_get_rate(s->clk);
s->port.type = PORT_IMX;
@ -728,7 +758,7 @@ static int __devinit mxs_auart_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, s);
auart_port[pdev->id] = s;
auart_port[s->port.line] = s;
mxs_auart_reset(&s->port);
@ -769,12 +799,19 @@ static int __devexit mxs_auart_remove(struct platform_device *pdev)
return 0;
}
static struct of_device_id mxs_auart_dt_ids[] = {
{ .compatible = "fsl,imx23-auart", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, mxs_auart_dt_ids);
static struct platform_driver mxs_auart_driver = {
.probe = mxs_auart_probe,
.remove = __devexit_p(mxs_auart_remove),
.driver = {
.name = "mxs-auart",
.owner = THIS_MODULE,
.of_match_table = mxs_auart_dt_ids,
},
};
@ -807,3 +844,4 @@ module_init(mxs_auart_init);
module_exit(mxs_auart_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Freescale MXS application uart driver");
MODULE_ALIAS("platform:mxs-auart");