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Diffstat (limited to '')
| -rw-r--r-- | drivers/hid/hid-picolcd_backlight.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/drivers/hid/hid-picolcd_backlight.c b/drivers/hid/hid-picolcd_backlight.c new file mode 100644 index 000000000..5bd2a8c4b --- /dev/null +++ b/drivers/hid/hid-picolcd_backlight.c @@ -0,0 +1,109 @@ +// SPDX-License-Identifier: GPL-2.0-only +/*************************************************************************** + * Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org> * + * * + * Based on Logitech G13 driver (v0.4) * + * Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu> * + * * + ***************************************************************************/ + +#include <linux/hid.h> + +#include <linux/fb.h> +#include <linux/backlight.h> + +#include "hid-picolcd.h" + +static int picolcd_get_brightness(struct backlight_device *bdev) +{ + struct picolcd_data *data = bl_get_data(bdev); + return data->lcd_brightness; +} + +static int picolcd_set_brightness(struct backlight_device *bdev) +{ + struct picolcd_data *data = bl_get_data(bdev); + struct hid_report *report = picolcd_out_report(REPORT_BRIGHTNESS, data->hdev); + unsigned long flags; + + if (!report || report->maxfield != 1 || report->field[0]->report_count != 1) + return -ENODEV; + + data->lcd_brightness = bdev->props.brightness & 0x0ff; + data->lcd_power = bdev->props.power; + spin_lock_irqsave(&data->lock, flags); + hid_set_field(report->field[0], 0, data->lcd_power == FB_BLANK_UNBLANK ? data->lcd_brightness : 0); + if (!(data->status & PICOLCD_FAILED)) + hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT); + spin_unlock_irqrestore(&data->lock, flags); + return 0; +} + +static int picolcd_check_bl_fb(struct backlight_device *bdev, struct fb_info *fb) +{ + return fb && fb == picolcd_fbinfo((struct picolcd_data *)bl_get_data(bdev)); +} + +static const struct backlight_ops picolcd_blops = { + .update_status = picolcd_set_brightness, + .get_brightness = picolcd_get_brightness, + .check_fb = picolcd_check_bl_fb, +}; + +int picolcd_init_backlight(struct picolcd_data *data, struct hid_report *report) +{ + struct device *dev = &data->hdev->dev; + struct backlight_device *bdev; + struct backlight_properties props; + if (!report) + return -ENODEV; + if (report->maxfield != 1 || report->field[0]->report_count != 1 || + report->field[0]->report_size != 8) { + dev_err(dev, "unsupported BRIGHTNESS report"); + return -EINVAL; + } + + memset(&props, 0, sizeof(props)); + props.type = BACKLIGHT_RAW; + props.max_brightness = 0xff; + bdev = backlight_device_register(dev_name(dev), dev, data, + &picolcd_blops, &props); + if (IS_ERR(bdev)) { + dev_err(dev, "failed to register backlight\n"); + return PTR_ERR(bdev); + } + bdev->props.brightness = 0xff; + data->lcd_brightness = 0xff; + data->backlight = bdev; + picolcd_set_brightness(bdev); + return 0; +} + +void picolcd_exit_backlight(struct picolcd_data *data) +{ + struct backlight_device *bdev = data->backlight; + + data->backlight = NULL; + backlight_device_unregister(bdev); +} + +int picolcd_resume_backlight(struct picolcd_data *data) +{ + if (!data->backlight) + return 0; + return picolcd_set_brightness(data->backlight); +} + +#ifdef CONFIG_PM +void picolcd_suspend_backlight(struct picolcd_data *data) +{ + int bl_power = data->lcd_power; + if (!data->backlight) + return; + + data->backlight->props.power = FB_BLANK_POWERDOWN; + picolcd_set_brightness(data->backlight); + data->lcd_power = data->backlight->props.power = bl_power; +} +#endif /* CONFIG_PM */ + |