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1// SPDX-License-Identifier: GPL-2.0-only2/***************************************************************************3 * Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org> *4 * *5 * Based on Logitech G13 driver (v0.4) *6 * Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu> *7 * *8 ***************************************************************************/9 10#include <linux/hid.h>11 12#include <linux/fb.h>13#include <linux/lcd.h>14 15#include "hid-picolcd.h"16 17/*18 * lcd class device19 */20static int picolcd_get_contrast(struct lcd_device *ldev)21{22 struct picolcd_data *data = lcd_get_data(ldev);23 return data->lcd_contrast;24}25 26static int picolcd_set_contrast(struct lcd_device *ldev, int contrast)27{28 struct picolcd_data *data = lcd_get_data(ldev);29 struct hid_report *report = picolcd_out_report(REPORT_CONTRAST, data->hdev);30 unsigned long flags;31 32 if (!report || report->maxfield != 1 || report->field[0]->report_count != 1)33 return -ENODEV;34 35 data->lcd_contrast = contrast & 0x0ff;36 spin_lock_irqsave(&data->lock, flags);37 hid_set_field(report->field[0], 0, data->lcd_contrast);38 if (!(data->status & PICOLCD_FAILED))39 hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);40 spin_unlock_irqrestore(&data->lock, flags);41 return 0;42}43 44static int picolcd_check_lcd_fb(struct lcd_device *ldev, struct fb_info *fb)45{46 return fb && fb == picolcd_fbinfo((struct picolcd_data *)lcd_get_data(ldev));47}48 49static const struct lcd_ops picolcd_lcdops = {50 .get_contrast = picolcd_get_contrast,51 .set_contrast = picolcd_set_contrast,52 .check_fb = picolcd_check_lcd_fb,53};54 55int picolcd_init_lcd(struct picolcd_data *data, struct hid_report *report)56{57 struct device *dev = &data->hdev->dev;58 struct lcd_device *ldev;59 60 if (!report)61 return -ENODEV;62 if (report->maxfield != 1 || report->field[0]->report_count != 1 ||63 report->field[0]->report_size != 8) {64 dev_err(dev, "unsupported CONTRAST report");65 return -EINVAL;66 }67 68 ldev = lcd_device_register(dev_name(dev), dev, data, &picolcd_lcdops);69 if (IS_ERR(ldev)) {70 dev_err(dev, "failed to register LCD\n");71 return PTR_ERR(ldev);72 }73 ldev->props.max_contrast = 0x0ff;74 data->lcd_contrast = 0xe5;75 data->lcd = ldev;76 picolcd_set_contrast(ldev, 0xe5);77 return 0;78}79 80void picolcd_exit_lcd(struct picolcd_data *data)81{82 struct lcd_device *ldev = data->lcd;83 84 data->lcd = NULL;85 lcd_device_unregister(ldev);86}87 88int picolcd_resume_lcd(struct picolcd_data *data)89{90 if (!data->lcd)91 return 0;92 return picolcd_set_contrast(data->lcd, data->lcd_contrast);93}94 95