cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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kb3886_bl.c (4468B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 *  Backlight Driver for the KB3886 Backlight
      4 *
      5 *  Copyright (c) 2007-2008 Claudio Nieder
      6 *
      7 *  Based on corgi_bl.c by Richard Purdie and kb3886 driver by Robert Woerle
      8 */
      9
     10#include <linux/module.h>
     11#include <linux/kernel.h>
     12#include <linux/init.h>
     13#include <linux/platform_device.h>
     14#include <linux/mutex.h>
     15#include <linux/fb.h>
     16#include <linux/backlight.h>
     17#include <linux/delay.h>
     18#include <linux/dmi.h>
     19
     20#define KB3886_PARENT 0x64
     21#define KB3886_IO 0x60
     22#define KB3886_ADC_DAC_PWM 0xC4
     23#define KB3886_PWM0_WRITE 0x81
     24#define KB3886_PWM0_READ 0x41
     25
     26static DEFINE_MUTEX(bl_mutex);
     27
     28static void kb3886_bl_set_intensity(int intensity)
     29{
     30	mutex_lock(&bl_mutex);
     31	intensity = intensity&0xff;
     32	outb(KB3886_ADC_DAC_PWM, KB3886_PARENT);
     33	usleep_range(10000, 11000);
     34	outb(KB3886_PWM0_WRITE, KB3886_IO);
     35	usleep_range(10000, 11000);
     36	outb(intensity, KB3886_IO);
     37	mutex_unlock(&bl_mutex);
     38}
     39
     40struct kb3886bl_machinfo {
     41	int max_intensity;
     42	int default_intensity;
     43	int limit_mask;
     44	void (*set_bl_intensity)(int intensity);
     45};
     46
     47static struct kb3886bl_machinfo kb3886_bl_machinfo = {
     48	.max_intensity = 0xff,
     49	.default_intensity = 0xa0,
     50	.limit_mask = 0x7f,
     51	.set_bl_intensity = kb3886_bl_set_intensity,
     52};
     53
     54static struct platform_device kb3886bl_device = {
     55	.name		= "kb3886-bl",
     56	.dev		= {
     57		.platform_data	= &kb3886_bl_machinfo,
     58	},
     59	.id		= -1,
     60};
     61
     62static struct platform_device *devices[] __initdata = {
     63	&kb3886bl_device,
     64};
     65
     66/*
     67 * Back to driver
     68 */
     69
     70static int kb3886bl_intensity;
     71static struct backlight_device *kb3886_backlight_device;
     72static struct kb3886bl_machinfo *bl_machinfo;
     73
     74static unsigned long kb3886bl_flags;
     75#define KB3886BL_SUSPENDED     0x01
     76
     77static const struct dmi_system_id kb3886bl_device_table[] __initconst = {
     78	{
     79		.ident = "Sahara Touch-iT",
     80		.matches = {
     81			DMI_MATCH(DMI_SYS_VENDOR, "SDV"),
     82			DMI_MATCH(DMI_PRODUCT_NAME, "iTouch T201"),
     83		},
     84	},
     85	{ }
     86};
     87
     88static int kb3886bl_send_intensity(struct backlight_device *bd)
     89{
     90	int intensity = backlight_get_brightness(bd);
     91
     92	if (kb3886bl_flags & KB3886BL_SUSPENDED)
     93		intensity = 0;
     94
     95	bl_machinfo->set_bl_intensity(intensity);
     96
     97	kb3886bl_intensity = intensity;
     98	return 0;
     99}
    100
    101#ifdef CONFIG_PM_SLEEP
    102static int kb3886bl_suspend(struct device *dev)
    103{
    104	struct backlight_device *bd = dev_get_drvdata(dev);
    105
    106	kb3886bl_flags |= KB3886BL_SUSPENDED;
    107	backlight_update_status(bd);
    108	return 0;
    109}
    110
    111static int kb3886bl_resume(struct device *dev)
    112{
    113	struct backlight_device *bd = dev_get_drvdata(dev);
    114
    115	kb3886bl_flags &= ~KB3886BL_SUSPENDED;
    116	backlight_update_status(bd);
    117	return 0;
    118}
    119#endif
    120
    121static SIMPLE_DEV_PM_OPS(kb3886bl_pm_ops, kb3886bl_suspend, kb3886bl_resume);
    122
    123static int kb3886bl_get_intensity(struct backlight_device *bd)
    124{
    125	return kb3886bl_intensity;
    126}
    127
    128static const struct backlight_ops kb3886bl_ops = {
    129	.get_brightness = kb3886bl_get_intensity,
    130	.update_status  = kb3886bl_send_intensity,
    131};
    132
    133static int kb3886bl_probe(struct platform_device *pdev)
    134{
    135	struct backlight_properties props;
    136	struct kb3886bl_machinfo *machinfo = dev_get_platdata(&pdev->dev);
    137
    138	bl_machinfo = machinfo;
    139	if (!machinfo->limit_mask)
    140		machinfo->limit_mask = -1;
    141
    142	memset(&props, 0, sizeof(struct backlight_properties));
    143	props.type = BACKLIGHT_RAW;
    144	props.max_brightness = machinfo->max_intensity;
    145	kb3886_backlight_device = devm_backlight_device_register(&pdev->dev,
    146							"kb3886-bl", &pdev->dev,
    147							NULL, &kb3886bl_ops,
    148							&props);
    149	if (IS_ERR(kb3886_backlight_device))
    150		return PTR_ERR(kb3886_backlight_device);
    151
    152	platform_set_drvdata(pdev, kb3886_backlight_device);
    153
    154	kb3886_backlight_device->props.power = FB_BLANK_UNBLANK;
    155	kb3886_backlight_device->props.brightness = machinfo->default_intensity;
    156	backlight_update_status(kb3886_backlight_device);
    157
    158	return 0;
    159}
    160
    161static struct platform_driver kb3886bl_driver = {
    162	.probe		= kb3886bl_probe,
    163	.driver		= {
    164		.name	= "kb3886-bl",
    165		.pm	= &kb3886bl_pm_ops,
    166	},
    167};
    168
    169static int __init kb3886_init(void)
    170{
    171	if (!dmi_check_system(kb3886bl_device_table))
    172		return -ENODEV;
    173
    174	platform_add_devices(devices, ARRAY_SIZE(devices));
    175	return platform_driver_register(&kb3886bl_driver);
    176}
    177
    178static void __exit kb3886_exit(void)
    179{
    180	platform_driver_unregister(&kb3886bl_driver);
    181}
    182
    183module_init(kb3886_init);
    184module_exit(kb3886_exit);
    185
    186MODULE_AUTHOR("Claudio Nieder <private@claudio.ch>");
    187MODULE_DESCRIPTION("Tabletkiosk Sahara Touch-iT Backlight Driver");
    188MODULE_LICENSE("GPL");
    189MODULE_ALIAS("dmi:*:svnSDV:pniTouchT201:*");