video/backlight/jornada720_lcd.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  *
0004  * LCD driver for HP Jornada 700 series (710/720/728)
0005  * Copyright (C) 2006-2009 Kristoffer Ericson <kristoffer.ericson@gmail.com>
0006  */
0007
0008 #include <linux/device.h>
0009 #include <linux/fb.h>
0010 #include <linux/kernel.h>
0011 #include <linux/lcd.h>
0012 #include <linux/module.h>
0013 #include <linux/platform_device.h>
0014 #include <linux/delay.h>
0015
0016 #include <mach/jornada720.h>
0017 #include <mach/hardware.h>
0018
0019 #include <video/s1d13xxxfb.h>
0020
0021 #define LCD_MAX_CONTRAST    0xff
0022 #define LCD_DEF_CONTRAST    0x80
0023
0024 static int jornada_lcd_get_power(struct lcd_device *ld)
0025 {
0026     return PPSR & PPC_LDD2 ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
0027 }
0028
0029 static int jornada_lcd_get_contrast(struct lcd_device *ld)
0030 {
0031     int ret;
0032
0033     if (jornada_lcd_get_power(ld) != FB_BLANK_UNBLANK)
0034         return 0;
0035
0036     jornada_ssp_start();
0037
0038     if (jornada_ssp_byte(GETCONTRAST) == TXDUMMY) {
0039         ret = jornada_ssp_byte(TXDUMMY);
0040         goto success;
0041     }
0042
0043     dev_err(&ld->dev, "failed to set contrast\n");
0044     ret = -ETIMEDOUT;
0045
0046 success:
0047     jornada_ssp_end();
0048     return ret;
0049 }
0050
0051 static int jornada_lcd_set_contrast(struct lcd_device *ld, int value)
0052 {
0053     int ret = 0;
0054
0055     jornada_ssp_start();
0056
0057     /* start by sending our set contrast cmd to mcu */
0058     if (jornada_ssp_byte(SETCONTRAST) == TXDUMMY) {
0059         /* if successful push the new value */
0060         if (jornada_ssp_byte(value) == TXDUMMY)
0061             goto success;
0062     }
0063
0064     dev_err(&ld->dev, "failed to set contrast\n");
0065     ret = -ETIMEDOUT;
0066
0067 success:
0068     jornada_ssp_end();
0069     return ret;
0070 }
0071
0072 static int jornada_lcd_set_power(struct lcd_device *ld, int power)
0073 {
0074     if (power != FB_BLANK_UNBLANK) {
0075         PPSR &= ~PPC_LDD2;
0076         PPDR |= PPC_LDD2;
0077     } else {
0078         PPSR |= PPC_LDD2;
0079     }
0080
0081     return 0;
0082 }
0083
0084 static struct lcd_ops jornada_lcd_props = {
0085     .get_contrast = jornada_lcd_get_contrast,
0086     .set_contrast = jornada_lcd_set_contrast,
0087     .get_power = jornada_lcd_get_power,
0088     .set_power = jornada_lcd_set_power,
0089 };
0090
0091 static int jornada_lcd_probe(struct platform_device *pdev)
0092 {
0093     struct lcd_device *lcd_device;
0094     int ret;
0095
0096     lcd_device = devm_lcd_device_register(&pdev->dev, S1D_DEVICENAME,
0097                     &pdev->dev, NULL, &jornada_lcd_props);
0098
0099     if (IS_ERR(lcd_device)) {
0100         ret = PTR_ERR(lcd_device);
0101         dev_err(&pdev->dev, "failed to register device\n");
0102         return ret;
0103     }
0104
0105     platform_set_drvdata(pdev, lcd_device);
0106
0107     /* lets set our default values */
0108     jornada_lcd_set_contrast(lcd_device, LCD_DEF_CONTRAST);
0109     jornada_lcd_set_power(lcd_device, FB_BLANK_UNBLANK);
0110     /* give it some time to startup */
0111     msleep(100);
0112
0113     return 0;
0114 }
0115
0116 static struct platform_driver jornada_lcd_driver = {
0117     .probe  = jornada_lcd_probe,
0118     .driver = {
0119         .name   = "jornada_lcd",
0120     },
0121 };
0122
0123 module_platform_driver(jornada_lcd_driver);
0124
0125 MODULE_AUTHOR("Kristoffer Ericson <kristoffer.ericson@gmail.com>");
0126 MODULE_DESCRIPTION("HP Jornada 710/720/728 LCD driver");
0127 MODULE_LICENSE("GPL");