Re: [PATCH v6 7/8] Loongson: YeeLoong: add suspend driver

[Ralf Baechle <ralf@linux-mips.org>]

On Tue, Dec 01, 2009 at 07:11:55PM +0800, Wu Zhangin wrote:
> From: Wu Zhangin <wuzhangjin@gmail.com>
> Date:   Tue,  1 Dec 2009 19:11:55 +0800
> To: Ralf Baechle <ralf@linux-mips.org>
> Cc: linux-mips@linux-mips.org, zhangfx@lemote.com,
> 	Pavel Machek <pavel@ucw.cz>, "Rafael J. Wysocki" <rjw@sisk.pl>,
> 	linux-pm@lists.linux-foundation.org,
> 	Wu Zhangjin <wuzhangjin@gmail.com>
> Subject: [PATCH v6 7/8] Loongson: YeeLoong: add suspend driver
> 
> From: Wu Zhangjin <wuzhangjin@gmail.com>
> 
> This patch adds Suspend Driver, which will suspend the YeeLoong Platform
> specific devices.
> 
> Acked-by: Pavel Machek <pavel@ucw.cz>
> Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
> ---
>  .../loongson/lemote-2f/yeeloong_laptop/Kconfig     |    8 +
>  .../loongson/lemote-2f/yeeloong_laptop/Makefile    |    1 +
>  .../lemote-2f/yeeloong_laptop/yl_suspend.c         |  135 ++++++++++++++++++++
>  3 files changed, 144 insertions(+), 0 deletions(-)
>  create mode 100644 arch/mips/loongson/lemote-2f/yeeloong_laptop/yl_suspend.c
> 
> diff --git a/arch/mips/loongson/lemote-2f/yeeloong_laptop/Kconfig b/arch/mips/loongson/lemote-2f/yeeloong_laptop/Kconfig
> index 7cf6071..f1211b4 100644
> --- a/arch/mips/loongson/lemote-2f/yeeloong_laptop/Kconfig
> +++ b/arch/mips/loongson/lemote-2f/yeeloong_laptop/Kconfig
> @@ -45,4 +45,12 @@ config YEELOONG_VO
>  	  This option adds Video Output Driver, which provides standard
>  	  interface to turn on/off the video output of LCD, CRT.
>  
> +config YEELOONG_SUSPEND
> +	tristate "Suspend Driver"
> +	depends on YEELOONG_VO && LOONGSON_SUSPEND
> +	default y
> +	help
> +	  This option adds Suspend Driver, which will suspend the YeeLoong
> +	  Platform specific devices.
> +
>  endif
> diff --git a/arch/mips/loongson/lemote-2f/yeeloong_laptop/Makefile b/arch/mips/loongson/lemote-2f/yeeloong_laptop/Makefile
> index aa01140..29f8050 100644
> --- a/arch/mips/loongson/lemote-2f/yeeloong_laptop/Makefile
> +++ b/arch/mips/loongson/lemote-2f/yeeloong_laptop/Makefile
> @@ -6,3 +6,4 @@ obj-$(CONFIG_YEELOONG_BACKLIGHT) += yl_backlight.o
>  obj-$(CONFIG_YEELOONG_BATTERY) += yl_battery.o
>  obj-$(CONFIG_YEELOONG_HWMON) += yl_hwmon.o
>  obj-$(CONFIG_YEELOONG_VO) += yl_vo.o
> +obj-$(CONFIG_YEELOONG_SUSPEND) += yl_suspend.o
> diff --git a/arch/mips/loongson/lemote-2f/yeeloong_laptop/yl_suspend.c b/arch/mips/loongson/lemote-2f/yeeloong_laptop/yl_suspend.c
> new file mode 100644
> index 0000000..9f53a69
> --- /dev/null
> +++ b/arch/mips/loongson/lemote-2f/yeeloong_laptop/yl_suspend.c
> @@ -0,0 +1,135 @@
> +/*
> + * YeeLoong Platform Specific Suspend Driver
> + *
> + *  Copyright (C) 2009 Lemote Inc.
> + *  Author: Wu Zhangjin <wuzj@lemote.com>
> + *
> + *  This program is free software; you can redistribute it and/or modify
> + *  it under the terms of the GNU General Public License version 2 as
> + *  published by the Free Software Foundation.
> + */
> +
> +#include <linux/err.h>
> +#include <linux/platform_device.h>
> +
> +#include <asm/bootinfo.h>
> +
> +#include "ec_kb3310b.h"
> +
> +MODULE_AUTHOR("Wu Zhangjin <wuzj@lemote.com>");
> +MODULE_DESCRIPTION("YeeLoong laptop suspend driver");
> +MODULE_LICENSE("GPL");
> +
> +static struct platform_device *yeeloong_pdev;
> +
> +static void usb_ports_set(int status)
> +{
> +	status = !!status;
> +
> +	ec_write(REG_USB0_FLAG, status);
> +	ec_write(REG_USB1_FLAG, status);
> +	ec_write(REG_USB2_FLAG, status);
> +}
> +
> +static int yeeloong_suspend(struct platform_device *pdev,
> +		pm_message_t state)
> +{
> +	pr_info("yeeloong specific suspend\n");
> +
> +	/* Turn off LCD */
> +	yeeloong_lcd_vo_set(BIT_DISPLAY_LCD_OFF);
> +	/* Turn off CRT */
> +	yeeloong_crt_vo_set(BIT_CRT_DETECT_UNPLUG);
> +	/* Poweroff three usb ports */
> +	usb_ports_set(BIT_USB_FLAG_OFF);
> +
> +	return 0;
> +}
> +
> +static int yeeloong_resume(struct platform_device *pdev)
> +{
> +	pr_info("yeeloong specific resume\n");
> +
> +	/* Resume the status of lcd & crt */
> +	yeeloong_lcd_vo_set(BIT_DISPLAY_LCD_ON);
> +	yeeloong_crt_vo_set(BIT_CRT_DETECT_PLUG);
> +
> +	/* Poweron three usb ports */
> +	usb_ports_set(BIT_USB_FLAG_ON);
> +
> +	return 0;
> +}
> +
> +static struct platform_driver platform_driver = {
> +	.driver = {
> +		   .name = "yeeloong-laptop",
> +		   .owner = THIS_MODULE,
> +		   },
> +	.suspend = yeeloong_suspend,
> +	.resume = yeeloong_resume,
> +};
> +
> +static ssize_t yeeloong_pdev_name_show(struct device *dev,
> +				       struct device_attribute *attr, char *buf)
> +{
> +	return sprintf(buf, "yeeloong laptop\n");
> +}
> +
> +static struct device_attribute dev_attr_yeeloong_pdev_name =
> +__ATTR(name, S_IRUGO, yeeloong_pdev_name_show, NULL);
> +
> +static int __init yeeloong_suspend_init(void)
> +{
> +	int ret;
> +
> +	if (mips_machtype != MACH_LEMOTE_YL2F89) {
> +		pr_err("This Driver is only for YeeLoong laptop\n");
> +		return -EFAULT;
> +	}

No need to signal an error here.  A platform device should only be
registered on a platform that actually has the device.  If you handle
all that registration business in a central platform.c file which
always is compiled into the YeeLoong kernel, this check can go away and
you at the same time assure the actual driver module can only be loaded
into the right kernel.

> +
> +	/* Register platform stuff */
> +	ret = platform_driver_register(&platform_driver);
> +	if (ret)
> +		return ret;
> +
> +	yeeloong_pdev = platform_device_alloc("yeeloong-laptop", -1);
> +	if (!yeeloong_pdev) {
> +		ret = -ENOMEM;
> +		platform_driver_unregister(&platform_driver);
> +		return ret;
> +	}
> +
> +	ret = platform_device_add(yeeloong_pdev);
> +	if (ret) {
> +		platform_device_put(yeeloong_pdev);
> +		return ret;
> +	}
> +
> +	if (IS_ERR(yeeloong_pdev)) {
> +		ret = PTR_ERR(yeeloong_pdev);
> +		yeeloong_pdev = NULL;
> +		pr_err("Fail to register platform device\n");
> +		return ret;
> +	}
> +
> +	ret = device_create_file(&yeeloong_pdev->dev,
> +				 &dev_attr_yeeloong_pdev_name);
> +	if (ret) {
> +		pr_err("Fail to create sysfs device attributes\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void __exit yeeloong_suspend_exit(void)
> +{
> +	if (yeeloong_pdev) {
> +		platform_device_unregister(yeeloong_pdev);
> +		yeeloong_pdev = NULL;
> +		platform_driver_unregister(&platform_driver);
> +	}
> +}
> +
> +module_init(yeeloong_suspend_init);
> +module_exit(yeeloong_suspend_exit);
> -- 
> 1.6.2.1

  Ralf