Release 4.14 arch/powerpc/platforms/powermac/backlight.c
/*
* Miscellaneous procedures for dealing with the PowerMac hardware.
* Contains support for the backlight.
*
* Copyright (C) 2000 Benjamin Herrenschmidt
* Copyright (C) 2006 Michael Hanselmann <linux-kernel@hansmi.ch>
*
*/
#include <linux/kernel.h>
#include <linux/fb.h>
#include <linux/backlight.h>
#include <linux/adb.h>
#include <linux/pmu.h>
#include <linux/atomic.h>
#include <linux/export.h>
#include <asm/prom.h>
#include <asm/backlight.h>
#define OLD_BACKLIGHT_MAX 15
static void pmac_backlight_key_worker(struct work_struct *work);
static void pmac_backlight_set_legacy_worker(struct work_struct *work);
static DECLARE_WORK(pmac_backlight_key_work, pmac_backlight_key_worker);
static DECLARE_WORK(pmac_backlight_set_legacy_work, pmac_backlight_set_legacy_worker);
/* Although these variables are used in interrupt context, it makes no sense to
* protect them. No user is able to produce enough key events per second and
* notice the errors that might happen.
*/
static int pmac_backlight_key_queued;
static int pmac_backlight_set_legacy_queued;
/* The via-pmu code allows the backlight to be grabbed, in which case the
* in-kernel control of the brightness needs to be disabled. This should
* only be used by really old PowerBooks.
*/
static atomic_t kernel_backlight_disabled = ATOMIC_INIT(0);
/* Protect the pmac_backlight variable below.
You should hold this lock when using the pmac_backlight pointer to
prevent its potential removal. */
DEFINE_MUTEX(pmac_backlight_mutex);
/* Main backlight storage
*
* Backlight drivers in this variable are required to have the "ops"
* attribute set and to have an update_status function.
*
* We can only store one backlight here, but since Apple laptops have only one
* internal display, it doesn't matter. Other backlight drivers can be used
* independently.
*
*/
struct backlight_device *pmac_backlight;
int pmac_has_backlight_type(const char *type)
{
struct device_node* bk_node = of_find_node_by_name(NULL, "backlight");
if (bk_node) {
const char *prop = of_get_property(bk_node,
"backlight-control", NULL);
if (prop && strncmp(prop, type, strlen(type)) == 0) {
of_node_put(bk_node);
return 1;
}
of_node_put(bk_node);
}
return 0;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Paul Mackerras | 47 | 60.26% | 1 | 20.00% |
| Stephen Rothwell | 16 | 20.51% | 2 | 40.00% |
| Michael Hanselmann | 14 | 17.95% | 1 | 20.00% |
| Jeremy Kerr | 1 | 1.28% | 1 | 20.00% |
| Total | 78 | 100.00% | 5 | 100.00% |
int pmac_backlight_curve_lookup(struct fb_info *info, int value)
{
int level = (FB_BACKLIGHT_LEVELS - 1);
if (info && info->bl_dev) {
int i, max = 0;
/* Look for biggest value */
for (i = 0; i < FB_BACKLIGHT_LEVELS; i++)
max = max((int)info->bl_curve[i], max);
/* Look for nearest value */
for (i = 0; i < FB_BACKLIGHT_LEVELS; i++) {
int diff = abs(info->bl_curve[i] - value);
if (diff < max) {
max = diff;
level = i;
}
}
}
return level;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 92 | 76.67% | 1 | 50.00% |
| Paul Mackerras | 28 | 23.33% | 1 | 50.00% |
| Total | 120 | 100.00% | 2 | 100.00% |
static void pmac_backlight_key_worker(struct work_struct *work)
{
if (atomic_read(&kernel_backlight_disabled))
return;
mutex_lock(&pmac_backlight_mutex);
if (pmac_backlight) {
struct backlight_properties *props;
int brightness;
props = &pmac_backlight->props;
brightness = props->brightness +
((pmac_backlight_key_queued?-1:1) *
(props->max_brightness / 15));
if (brightness < 0)
brightness = 0;
else if (brightness > props->max_brightness)
brightness = props->max_brightness;
props->brightness = brightness;
backlight_update_status(pmac_backlight);
}
mutex_unlock(&pmac_backlight_mutex);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 86 | 75.44% | 3 | 42.86% |
| Paul Mackerras | 23 | 20.18% | 1 | 14.29% |
| David Howells | 3 | 2.63% | 1 | 14.29% |
| Richard Purdie | 2 | 1.75% | 2 | 28.57% |
| Total | 114 | 100.00% | 7 | 100.00% |
/* This function is called in interrupt context */
void pmac_backlight_key(int direction)
{
if (atomic_read(&kernel_backlight_disabled))
return;
/* we can receive multiple interrupts here, but the scheduled work
* will run only once, with the last value
*/
pmac_backlight_key_queued = direction;
schedule_work(&pmac_backlight_key_work);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 26 | 92.86% | 3 | 75.00% |
| Paul Mackerras | 2 | 7.14% | 1 | 25.00% |
| Total | 28 | 100.00% | 4 | 100.00% |
static int __pmac_backlight_set_legacy_brightness(int brightness)
{
int error = -ENXIO;
mutex_lock(&pmac_backlight_mutex);
if (pmac_backlight) {
struct backlight_properties *props;
props = &pmac_backlight->props;
props->brightness = brightness *
(props->max_brightness + 1) /
(OLD_BACKLIGHT_MAX + 1);
if (props->brightness > props->max_brightness)
props->brightness = props->max_brightness;
else if (props->brightness < 0)
props->brightness = 0;
backlight_update_status(pmac_backlight);
error = 0;
}
mutex_unlock(&pmac_backlight_mutex);
return error;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 88 | 80.00% | 3 | 50.00% |
| Paul Mackerras | 20 | 18.18% | 1 | 16.67% |
| Richard Purdie | 2 | 1.82% | 2 | 33.33% |
| Total | 110 | 100.00% | 6 | 100.00% |
static void pmac_backlight_set_legacy_worker(struct work_struct *work)
{
if (atomic_read(&kernel_backlight_disabled))
return;
__pmac_backlight_set_legacy_brightness(pmac_backlight_set_legacy_queued);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 22 | 88.00% | 1 | 50.00% |
| David Howells | 3 | 12.00% | 1 | 50.00% |
| Total | 25 | 100.00% | 2 | 100.00% |
/* This function is called in interrupt context */
void pmac_backlight_set_legacy_brightness_pmu(int brightness) {
if (atomic_read(&kernel_backlight_disabled))
return;
pmac_backlight_set_legacy_queued = brightness;
schedule_work(&pmac_backlight_set_legacy_work);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 27 | 100.00% | 1 | 100.00% |
| Total | 27 | 100.00% | 1 | 100.00% |
int pmac_backlight_set_legacy_brightness(int brightness)
{
return __pmac_backlight_set_legacy_brightness(brightness);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 14 | 100.00% | 1 | 100.00% |
| Total | 14 | 100.00% | 1 | 100.00% |
int pmac_backlight_get_legacy_brightness()
{
int result = -ENXIO;
mutex_lock(&pmac_backlight_mutex);
if (pmac_backlight) {
struct backlight_properties *props;
props = &pmac_backlight->props;
result = props->brightness *
(OLD_BACKLIGHT_MAX + 1) /
(props->max_brightness + 1);
}
mutex_unlock(&pmac_backlight_mutex);
return result;
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 50 | 78.12% | 2 | 50.00% |
| Paul Mackerras | 13 | 20.31% | 1 | 25.00% |
| Richard Purdie | 1 | 1.56% | 1 | 25.00% |
| Total | 64 | 100.00% | 4 | 100.00% |
void pmac_backlight_disable()
{
atomic_inc(&kernel_backlight_disabled);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 11 | 100.00% | 1 | 100.00% |
| Total | 11 | 100.00% | 1 | 100.00% |
void pmac_backlight_enable()
{
atomic_dec(&kernel_backlight_disabled);
}
Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 11 | 100.00% | 1 | 100.00% |
| Total | 11 | 100.00% | 1 | 100.00% |
EXPORT_SYMBOL_GPL(pmac_backlight);
EXPORT_SYMBOL_GPL(pmac_backlight_mutex);
EXPORT_SYMBOL_GPL(pmac_has_backlight_type);
Overall Contributors
| Person | Tokens | Prop | Commits | CommitProp |
| Michael Hanselmann | 530 | 73.82% | 4 | 30.77% |
| Paul Mackerras | 148 | 20.61% | 1 | 7.69% |
| Stephen Rothwell | 16 | 2.23% | 2 | 15.38% |
| David Howells | 12 | 1.67% | 1 | 7.69% |
| Richard Purdie | 7 | 0.97% | 2 | 15.38% |
| Paul Gortmaker | 3 | 0.42% | 1 | 7.69% |
| Jeremy Kerr | 1 | 0.14% | 1 | 7.69% |
| Arun Sharma | 1 | 0.14% | 1 | 7.69% |
| Total | 718 | 100.00% | 13 | 100.00% |
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