1 /*************************************************************************** 2 * Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org> * 3 * * 4 * Based on Logitech G13 driver (v0.4) * 5 * Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu> * 6 * * 7 * This program is free software: you can redistribute it and/or modify * 8 * it under the terms of the GNU General Public License as published by * 9 * the Free Software Foundation, version 2 of the License. * 10 * * 11 * This driver is distributed in the hope that it will be useful, but * 12 * WITHOUT ANY WARRANTY; without even the implied warranty of * 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * 14 * General Public License for more details. * 15 * * 16 * You should have received a copy of the GNU General Public License * 17 * along with this software. If not see <http://www.gnu.org/licenses/>. * 18 ***************************************************************************/ 19 20 #include <linux/hid.h> 21 22 #include <linux/fb.h> 23 #include <linux/lcd.h> 24 25 #include "hid-picolcd.h" 26 27 /* 28 * lcd class device 29 */ 30 static int picolcd_get_contrast(struct lcd_device *ldev) 31 { 32 struct picolcd_data *data = lcd_get_data(ldev); 33 return data->lcd_contrast; 34 } 35 36 static int picolcd_set_contrast(struct lcd_device *ldev, int contrast) 37 { 38 struct picolcd_data *data = lcd_get_data(ldev); 39 struct hid_report *report = picolcd_out_report(REPORT_CONTRAST, data->hdev); 40 unsigned long flags; 41 42 if (!report || report->maxfield != 1 || report->field[0]->report_count != 1) 43 return -ENODEV; 44 45 data->lcd_contrast = contrast & 0x0ff; 46 spin_lock_irqsave(&data->lock, flags); 47 hid_set_field(report->field[0], 0, data->lcd_contrast); 48 if (!(data->status & PICOLCD_FAILED)) 49 hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT); 50 spin_unlock_irqrestore(&data->lock, flags); 51 return 0; 52 } 53 54 static int picolcd_check_lcd_fb(struct lcd_device *ldev, struct fb_info *fb) 55 { 56 return fb && fb == picolcd_fbinfo((struct picolcd_data *)lcd_get_data(ldev)); 57 } 58 59 static struct lcd_ops picolcd_lcdops = { 60 .get_contrast = picolcd_get_contrast, 61 .set_contrast = picolcd_set_contrast, 62 .check_fb = picolcd_check_lcd_fb, 63 }; 64 65 int picolcd_init_lcd(struct picolcd_data *data, struct hid_report *report) 66 { 67 struct device *dev = &data->hdev->dev; 68 struct lcd_device *ldev; 69 70 if (!report) 71 return -ENODEV; 72 if (report->maxfield != 1 || report->field[0]->report_count != 1 || 73 report->field[0]->report_size != 8) { 74 dev_err(dev, "unsupported CONTRAST report"); 75 return -EINVAL; 76 } 77 78 ldev = lcd_device_register(dev_name(dev), dev, data, &picolcd_lcdops); 79 if (IS_ERR(ldev)) { 80 dev_err(dev, "failed to register LCD\n"); 81 return PTR_ERR(ldev); 82 } 83 ldev->props.max_contrast = 0x0ff; 84 data->lcd_contrast = 0xe5; 85 data->lcd = ldev; 86 picolcd_set_contrast(ldev, 0xe5); 87 return 0; 88 } 89 90 void picolcd_exit_lcd(struct picolcd_data *data) 91 { 92 struct lcd_device *ldev = data->lcd; 93 94 data->lcd = NULL; 95 if (ldev) 96 lcd_device_unregister(ldev); 97 } 98 99 int picolcd_resume_lcd(struct picolcd_data *data) 100 { 101 if (!data->lcd) 102 return 0; 103 return picolcd_set_contrast(data->lcd, data->lcd_contrast); 104 } 105 106