mirror of
https://github.com/torvalds/linux.git
synced 2024-11-13 23:51:39 +00:00
b8beae9494
'struct lcd_ops' is not modified by core backlight code, so it can be made const for increased code safety. Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Reviewed-by: Bruno Prémont <bonbons@linux-vserver.org> Link: https://lore.kernel.org/r/20240424-video-backlight-lcd-ops-v2-15-1aaa82b07bc6@kernel.org Signed-off-by: Lee Jones <lee@kernel.org>
95 lines
2.7 KiB
C
95 lines
2.7 KiB
C
// 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/lcd.h>
|
|
|
|
#include "hid-picolcd.h"
|
|
|
|
/*
|
|
* lcd class device
|
|
*/
|
|
static int picolcd_get_contrast(struct lcd_device *ldev)
|
|
{
|
|
struct picolcd_data *data = lcd_get_data(ldev);
|
|
return data->lcd_contrast;
|
|
}
|
|
|
|
static int picolcd_set_contrast(struct lcd_device *ldev, int contrast)
|
|
{
|
|
struct picolcd_data *data = lcd_get_data(ldev);
|
|
struct hid_report *report = picolcd_out_report(REPORT_CONTRAST, data->hdev);
|
|
unsigned long flags;
|
|
|
|
if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)
|
|
return -ENODEV;
|
|
|
|
data->lcd_contrast = contrast & 0x0ff;
|
|
spin_lock_irqsave(&data->lock, flags);
|
|
hid_set_field(report->field[0], 0, data->lcd_contrast);
|
|
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_lcd_fb(struct lcd_device *ldev, struct fb_info *fb)
|
|
{
|
|
return fb && fb == picolcd_fbinfo((struct picolcd_data *)lcd_get_data(ldev));
|
|
}
|
|
|
|
static const struct lcd_ops picolcd_lcdops = {
|
|
.get_contrast = picolcd_get_contrast,
|
|
.set_contrast = picolcd_set_contrast,
|
|
.check_fb = picolcd_check_lcd_fb,
|
|
};
|
|
|
|
int picolcd_init_lcd(struct picolcd_data *data, struct hid_report *report)
|
|
{
|
|
struct device *dev = &data->hdev->dev;
|
|
struct lcd_device *ldev;
|
|
|
|
if (!report)
|
|
return -ENODEV;
|
|
if (report->maxfield != 1 || report->field[0]->report_count != 1 ||
|
|
report->field[0]->report_size != 8) {
|
|
dev_err(dev, "unsupported CONTRAST report");
|
|
return -EINVAL;
|
|
}
|
|
|
|
ldev = lcd_device_register(dev_name(dev), dev, data, &picolcd_lcdops);
|
|
if (IS_ERR(ldev)) {
|
|
dev_err(dev, "failed to register LCD\n");
|
|
return PTR_ERR(ldev);
|
|
}
|
|
ldev->props.max_contrast = 0x0ff;
|
|
data->lcd_contrast = 0xe5;
|
|
data->lcd = ldev;
|
|
picolcd_set_contrast(ldev, 0xe5);
|
|
return 0;
|
|
}
|
|
|
|
void picolcd_exit_lcd(struct picolcd_data *data)
|
|
{
|
|
struct lcd_device *ldev = data->lcd;
|
|
|
|
data->lcd = NULL;
|
|
lcd_device_unregister(ldev);
|
|
}
|
|
|
|
int picolcd_resume_lcd(struct picolcd_data *data)
|
|
{
|
|
if (!data->lcd)
|
|
return 0;
|
|
return picolcd_set_contrast(data->lcd, data->lcd_contrast);
|
|
}
|
|
|