Commit 8ad3b135 authored by Jingchang Lu's avatar Jingchang Lu Committed by Greg Kroah-Hartman
Browse files

serial: of-serial: add PM suspend/resume support 



This adds suspend/resume support for the of-serial driver
to provide power management support on devices attatched.

The handling may vary since not every of_serial device is
an 8250 port. Currently only 8250 port handling is added
in the suspend/resume function based on the type switch.

Signed-off-by: default avatarJingchang Lu <jingchang.lu@freescale.com>
Acked-by: default avatarArnd Bergmann <arnd@arndb.de>
Tested-by: default avatarJoseph Lo <josephl@nvidia.com>
Reviewed-by: default avatarPeter Hurley <peter@hurleysoftware.com>
Tested-by: default avatarFlorina Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 261119f7

drivers/tty/serial/of_serial.c

+66 −0
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
 *  2 of the License, or (at your option) any later version.

 *

 */

#include <linux/console.h>

#include <linux/module.h>

#include <linux/slab.h>

#include <linux/delay.h>
@@ -247,6 +248,70 @@ static int of_platform_serial_remove(struct platform_device *ofdev) 
	return 0;

}



#ifdef CONFIG_PM_SLEEP

#ifdef CONFIG_SERIAL_8250

static void of_serial_suspend_8250(struct of_serial_info *info)

{

	struct uart_8250_port *port8250 = serial8250_get_port(info->line);

	struct uart_port *port = &port8250->port;



	serial8250_suspend_port(info->line);

	if (info->clk && (!uart_console(port) || console_suspend_enabled))

		clk_disable_unprepare(info->clk);

}



static void of_serial_resume_8250(struct of_serial_info *info)

{

	struct uart_8250_port *port8250 = serial8250_get_port(info->line);

	struct uart_port *port = &port8250->port;



	if (info->clk && (!uart_console(port) || console_suspend_enabled))

		clk_prepare_enable(info->clk);



	serial8250_resume_port(info->line);

}

#else

static inline void of_serial_suspend_8250(struct of_serial_info *info)

{

}



static inline void of_serial_resume_8250(struct of_serial_info *info)

{

}

#endif



static int of_serial_suspend(struct device *dev)

{

	struct of_serial_info *info = dev_get_drvdata(dev);



	switch (info->type) {

	case PORT_8250 ... PORT_MAX_8250:

		of_serial_suspend_8250(info);

		break;

	default:

		break;

	}



	return 0;

}



static int of_serial_resume(struct device *dev)

{

	struct of_serial_info *info = dev_get_drvdata(dev);



	switch (info->type) {

	case PORT_8250 ... PORT_MAX_8250:

		of_serial_resume_8250(info);

		break;

	default:

		break;

	}



	return 0;

}

#endif

static SIMPLE_DEV_PM_OPS(of_serial_pm_ops, of_serial_suspend, of_serial_resume);



/*

 * A few common types, add more as needed.

 */
@@ -279,6 +344,7 @@ static struct platform_driver of_platform_serial_driver = { 
		.name = "of_serial",

		.owner = THIS_MODULE,

		.of_match_table = of_platform_serial_table,

		.pm = &of_serial_pm_ops,

	},

	.probe = of_platform_serial_probe,

	.remove = of_platform_serial_remove,

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