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 #include "usbhid/usbhid.h" 22 #include <linux/usb.h> 23 24 #include <linux/fb.h> 25 #include <linux/lcd.h> 26 27 #include "hid-picolcd.h" 28 29 /* 30 * lcd class device 31 */ 32 static int picolcd_get_contrast(struct lcd_device *ldev) 33 { 34 struct picolcd_data *data = lcd_get_data(ldev); 35 return data->lcd_contrast; 36 } 37 38 static int picolcd_set_contrast(struct lcd_device *ldev, int contrast) 39 { 40 struct picolcd_data *data = lcd_get_data(ldev); 41 struct hid_report *report = picolcd_out_report(REPORT_CONTRAST, data->hdev); 42 unsigned long flags; 43 44 if (!report || report->maxfield != 1 || report->field[0]->report_count != 1) 45 return -ENODEV; 46 47 data->lcd_contrast = contrast & 0x0ff; 48 spin_lock_irqsave(&data->lock, flags); 49 hid_set_field(report->field[0], 0, data->lcd_contrast); 50 if (!(data->status & PICOLCD_FAILED)) 51 usbhid_submit_report(data->hdev, report, USB_DIR_OUT); 52 spin_unlock_irqrestore(&data->lock, flags); 53 return 0; 54 } 55 56 static int picolcd_check_lcd_fb(struct lcd_device *ldev, struct fb_info *fb) 57 { 58 return fb && fb == picolcd_fbinfo((struct picolcd_data *)lcd_get_data(ldev)); 59 } 60 61 static struct lcd_ops picolcd_lcdops = { 62 .get_contrast = picolcd_get_contrast, 63 .set_contrast = picolcd_set_contrast, 64 .check_fb = picolcd_check_lcd_fb, 65 }; 66 67 int picolcd_init_lcd(struct picolcd_data *data, struct hid_report *report) 68 { 69 struct device *dev = &data->hdev->dev; 70 struct lcd_device *ldev; 71 72 if (!report) 73 return -ENODEV; 74 if (report->maxfield != 1 || report->field[0]->report_count != 1 || 75 report->field[0]->report_size != 8) { 76 dev_err(dev, "unsupported CONTRAST report"); 77 return -EINVAL; 78 } 79 80 ldev = lcd_device_register(dev_name(dev), dev, data, &picolcd_lcdops); 81 if (IS_ERR(ldev)) { 82 dev_err(dev, "failed to register LCD\n"); 83 return PTR_ERR(ldev); 84 } 85 ldev->props.max_contrast = 0x0ff; 86 data->lcd_contrast = 0xe5; 87 data->lcd = ldev; 88 picolcd_set_contrast(ldev, 0xe5); 89 return 0; 90 } 91 92 void picolcd_exit_lcd(struct picolcd_data *data) 93 { 94 struct lcd_device *ldev = data->lcd; 95 96 data->lcd = NULL; 97 if (ldev) 98 lcd_device_unregister(ldev); 99 } 100 101 int picolcd_resume_lcd(struct picolcd_data *data) 102 { 103 if (!data->lcd) 104 return 0; 105 return picolcd_set_contrast(data->lcd, data->lcd_contrast); 106 } 107 108