![Ben Dooks](/assets/img/avatar_default.png)
Add the device to the notify callback's arguments in the PWM backlight driver. This brings the notify callback into line with the other callbacks defined by this driver. Signed-off-by: Ben Dooks <ben@simtec.co.uk> Signed-off-by: Simtec Linux Team <linux@simtec.co.uk> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
197 lines
4.6 KiB
C
197 lines
4.6 KiB
C
/*
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* linux/drivers/video/backlight/pwm_bl.c
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*
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* simple PWM based backlight control, board code has to setup
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* 1) pin configuration so PWM waveforms can output
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* 2) platform_data being correctly configured
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/module.h>
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#include <linux/kernel.h>
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#include <linux/init.h>
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#include <linux/platform_device.h>
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#include <linux/fb.h>
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#include <linux/backlight.h>
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#include <linux/err.h>
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#include <linux/pwm.h>
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#include <linux/pwm_backlight.h>
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struct pwm_bl_data {
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struct pwm_device *pwm;
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struct device *dev;
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unsigned int period;
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int (*notify)(struct device *,
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int brightness);
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};
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static int pwm_backlight_update_status(struct backlight_device *bl)
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{
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struct pwm_bl_data *pb = dev_get_drvdata(&bl->dev);
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int brightness = bl->props.brightness;
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int max = bl->props.max_brightness;
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if (bl->props.power != FB_BLANK_UNBLANK)
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brightness = 0;
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if (bl->props.fb_blank != FB_BLANK_UNBLANK)
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brightness = 0;
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if (pb->notify)
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brightness = pb->notify(pb->dev, brightness);
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if (brightness == 0) {
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pwm_config(pb->pwm, 0, pb->period);
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pwm_disable(pb->pwm);
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} else {
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pwm_config(pb->pwm, brightness * pb->period / max, pb->period);
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pwm_enable(pb->pwm);
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}
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return 0;
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}
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static int pwm_backlight_get_brightness(struct backlight_device *bl)
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{
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return bl->props.brightness;
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}
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static const struct backlight_ops pwm_backlight_ops = {
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.update_status = pwm_backlight_update_status,
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.get_brightness = pwm_backlight_get_brightness,
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};
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static int pwm_backlight_probe(struct platform_device *pdev)
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{
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struct platform_pwm_backlight_data *data = pdev->dev.platform_data;
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struct backlight_device *bl;
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struct pwm_bl_data *pb;
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int ret;
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if (!data) {
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dev_err(&pdev->dev, "failed to find platform data\n");
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return -EINVAL;
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}
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if (data->init) {
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ret = data->init(&pdev->dev);
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if (ret < 0)
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return ret;
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}
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pb = kzalloc(sizeof(*pb), GFP_KERNEL);
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if (!pb) {
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dev_err(&pdev->dev, "no memory for state\n");
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ret = -ENOMEM;
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goto err_alloc;
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}
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pb->period = data->pwm_period_ns;
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pb->notify = data->notify;
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pb->dev = &pdev->dev;
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pb->pwm = pwm_request(data->pwm_id, "backlight");
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if (IS_ERR(pb->pwm)) {
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dev_err(&pdev->dev, "unable to request PWM for backlight\n");
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ret = PTR_ERR(pb->pwm);
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goto err_pwm;
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} else
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dev_dbg(&pdev->dev, "got pwm for backlight\n");
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bl = backlight_device_register(dev_name(&pdev->dev), &pdev->dev,
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pb, &pwm_backlight_ops);
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if (IS_ERR(bl)) {
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dev_err(&pdev->dev, "failed to register backlight\n");
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ret = PTR_ERR(bl);
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goto err_bl;
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}
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bl->props.max_brightness = data->max_brightness;
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bl->props.brightness = data->dft_brightness;
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backlight_update_status(bl);
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platform_set_drvdata(pdev, bl);
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return 0;
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err_bl:
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pwm_free(pb->pwm);
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err_pwm:
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kfree(pb);
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err_alloc:
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if (data->exit)
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data->exit(&pdev->dev);
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return ret;
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}
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static int pwm_backlight_remove(struct platform_device *pdev)
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{
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struct platform_pwm_backlight_data *data = pdev->dev.platform_data;
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struct backlight_device *bl = platform_get_drvdata(pdev);
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struct pwm_bl_data *pb = dev_get_drvdata(&bl->dev);
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backlight_device_unregister(bl);
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pwm_config(pb->pwm, 0, pb->period);
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pwm_disable(pb->pwm);
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pwm_free(pb->pwm);
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kfree(pb);
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if (data->exit)
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data->exit(&pdev->dev);
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return 0;
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}
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#ifdef CONFIG_PM
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static int pwm_backlight_suspend(struct platform_device *pdev,
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pm_message_t state)
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{
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struct backlight_device *bl = platform_get_drvdata(pdev);
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struct pwm_bl_data *pb = dev_get_drvdata(&bl->dev);
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if (pb->notify)
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pb->notify(pb->dev, 0);
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pwm_config(pb->pwm, 0, pb->period);
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pwm_disable(pb->pwm);
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return 0;
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}
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static int pwm_backlight_resume(struct platform_device *pdev)
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{
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struct backlight_device *bl = platform_get_drvdata(pdev);
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backlight_update_status(bl);
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return 0;
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}
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#else
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#define pwm_backlight_suspend NULL
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#define pwm_backlight_resume NULL
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#endif
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static struct platform_driver pwm_backlight_driver = {
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.driver = {
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.name = "pwm-backlight",
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.owner = THIS_MODULE,
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},
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.probe = pwm_backlight_probe,
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.remove = pwm_backlight_remove,
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.suspend = pwm_backlight_suspend,
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.resume = pwm_backlight_resume,
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};
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static int __init pwm_backlight_init(void)
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{
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return platform_driver_register(&pwm_backlight_driver);
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}
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module_init(pwm_backlight_init);
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static void __exit pwm_backlight_exit(void)
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{
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platform_driver_unregister(&pwm_backlight_driver);
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}
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module_exit(pwm_backlight_exit);
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MODULE_DESCRIPTION("PWM based Backlight Driver");
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MODULE_LICENSE("GPL");
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MODULE_ALIAS("platform:pwm-backlight");
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