linux_dsm_epyc7002/drivers/leds/leds-gpio.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* LEDs driver for GPIOs
*
* Copyright (C) 2007 8D Technologies inc.
* Raphael Assenat <raph@8d.com>
* Copyright (C) 2008 Freescale Semiconductor, Inc.
*/
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/kernel.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/property.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 15:04:11 +07:00
#include <linux/slab.h>
struct gpio_led_data {
struct led_classdev cdev;
struct gpio_desc *gpiod;
u8 can_sleep;
u8 blinking;
gpio_blink_set_t platform_gpio_blink_set;
};
static inline struct gpio_led_data *
cdev_to_gpio_led_data(struct led_classdev *led_cdev)
{
return container_of(led_cdev, struct gpio_led_data, cdev);
}
static void gpio_led_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
int level;
if (value == LED_OFF)
level = 0;
else
level = 1;
if (led_dat->blinking) {
led_dat->platform_gpio_blink_set(led_dat->gpiod, level,
NULL, NULL);
led_dat->blinking = 0;
} else {
if (led_dat->can_sleep)
gpiod_set_value_cansleep(led_dat->gpiod, level);
else
gpiod_set_value(led_dat->gpiod, level);
}
}
static int gpio_led_set_blocking(struct led_classdev *led_cdev,
enum led_brightness value)
{
gpio_led_set(led_cdev, value);
return 0;
}
static int gpio_blink_set(struct led_classdev *led_cdev,
unsigned long *delay_on, unsigned long *delay_off)
{
struct gpio_led_data *led_dat = cdev_to_gpio_led_data(led_cdev);
led_dat->blinking = 1;
return led_dat->platform_gpio_blink_set(led_dat->gpiod, GPIO_LED_BLINK,
delay_on, delay_off);
}
static int create_gpio_led(const struct gpio_led *template,
struct gpio_led_data *led_dat, struct device *parent,
struct fwnode_handle *fwnode, gpio_blink_set_t blink_set)
{
struct led_init_data init_data = {};
leds: Add options to have GPIO LEDs start on or keep their state There already is a "default-on" trigger but there are problems with it. For one, it's a inefficient way to do it and requires led trigger support to be compiled in. But the real reason is that is produces a glitch on the LED. The GPIO is allocate with the LED *off*, then *later* when the trigger runs it is turned back on. If the LED was already on via the GPIO's reset default or action of the firmware, this produces a glitch where the LED goes from on to off to on. While normally this is fast enough that it wouldn't be noticeable to a human observer, there are still serious problems. One is that there may be something else on the GPIO line, like a hardware alarm or watchdog, that is fast enough to notice the glitch. Another is that the kernel may panic before the LED is turned back on, thus hanging with the LED in the wrong state. This is not just speculation, but actually happened to me with an embedded system that has an LED which should turn off when the kernel finishes booting, which was left in the incorrect state due to a bug in the OF LED binding code. We also let GPIO LEDs get their initial value from whatever the current state of the GPIO line is. On some systems the LEDs are put into some state by the firmware or hardware before Linux boots, and it is desired to have them keep this state which is otherwise unknown to Linux. This requires that the underlying GPIO driver support reading the value of output GPIOs. Some drivers support this and some do not. The platform device binding gains a field in the platform data "default_state" that controls this. There are three constants defined to select from on, off, or keeping the current state. The OpenFirmware binding uses a property named "default-state" that can be set to "on", "off", or "keep". The default if the property isn't present is off. Signed-off-by: Trent Piepho <xyzzy@speakeasy.org> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-05-13 05:33:12 +07:00
int ret, state;
led_dat->cdev.default_trigger = template->default_trigger;
led_dat->can_sleep = gpiod_cansleep(led_dat->gpiod);
if (!led_dat->can_sleep)
led_dat->cdev.brightness_set = gpio_led_set;
else
led_dat->cdev.brightness_set_blocking = gpio_led_set_blocking;
led_dat->blinking = 0;
if (blink_set) {
led_dat->platform_gpio_blink_set = blink_set;
led_dat->cdev.blink_set = gpio_blink_set;
}
if (template->default_state == LEDS_GPIO_DEFSTATE_KEEP) {
state = gpiod_get_value_cansleep(led_dat->gpiod);
if (state < 0)
return state;
} else {
leds: Add options to have GPIO LEDs start on or keep their state There already is a "default-on" trigger but there are problems with it. For one, it's a inefficient way to do it and requires led trigger support to be compiled in. But the real reason is that is produces a glitch on the LED. The GPIO is allocate with the LED *off*, then *later* when the trigger runs it is turned back on. If the LED was already on via the GPIO's reset default or action of the firmware, this produces a glitch where the LED goes from on to off to on. While normally this is fast enough that it wouldn't be noticeable to a human observer, there are still serious problems. One is that there may be something else on the GPIO line, like a hardware alarm or watchdog, that is fast enough to notice the glitch. Another is that the kernel may panic before the LED is turned back on, thus hanging with the LED in the wrong state. This is not just speculation, but actually happened to me with an embedded system that has an LED which should turn off when the kernel finishes booting, which was left in the incorrect state due to a bug in the OF LED binding code. We also let GPIO LEDs get their initial value from whatever the current state of the GPIO line is. On some systems the LEDs are put into some state by the firmware or hardware before Linux boots, and it is desired to have them keep this state which is otherwise unknown to Linux. This requires that the underlying GPIO driver support reading the value of output GPIOs. Some drivers support this and some do not. The platform device binding gains a field in the platform data "default_state" that controls this. There are three constants defined to select from on, off, or keeping the current state. The OpenFirmware binding uses a property named "default-state" that can be set to "on", "off", or "keep". The default if the property isn't present is off. Signed-off-by: Trent Piepho <xyzzy@speakeasy.org> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-05-13 05:33:12 +07:00
state = (template->default_state == LEDS_GPIO_DEFSTATE_ON);
}
leds: Add options to have GPIO LEDs start on or keep their state There already is a "default-on" trigger but there are problems with it. For one, it's a inefficient way to do it and requires led trigger support to be compiled in. But the real reason is that is produces a glitch on the LED. The GPIO is allocate with the LED *off*, then *later* when the trigger runs it is turned back on. If the LED was already on via the GPIO's reset default or action of the firmware, this produces a glitch where the LED goes from on to off to on. While normally this is fast enough that it wouldn't be noticeable to a human observer, there are still serious problems. One is that there may be something else on the GPIO line, like a hardware alarm or watchdog, that is fast enough to notice the glitch. Another is that the kernel may panic before the LED is turned back on, thus hanging with the LED in the wrong state. This is not just speculation, but actually happened to me with an embedded system that has an LED which should turn off when the kernel finishes booting, which was left in the incorrect state due to a bug in the OF LED binding code. We also let GPIO LEDs get their initial value from whatever the current state of the GPIO line is. On some systems the LEDs are put into some state by the firmware or hardware before Linux boots, and it is desired to have them keep this state which is otherwise unknown to Linux. This requires that the underlying GPIO driver support reading the value of output GPIOs. Some drivers support this and some do not. The platform device binding gains a field in the platform data "default_state" that controls this. There are three constants defined to select from on, off, or keeping the current state. The OpenFirmware binding uses a property named "default-state" that can be set to "on", "off", or "keep". The default if the property isn't present is off. Signed-off-by: Trent Piepho <xyzzy@speakeasy.org> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-05-13 05:33:12 +07:00
led_dat->cdev.brightness = state ? LED_FULL : LED_OFF;
if (!template->retain_state_suspended)
led_dat->cdev.flags |= LED_CORE_SUSPENDRESUME;
if (template->panic_indicator)
led_dat->cdev.flags |= LED_PANIC_INDICATOR;
if (template->retain_state_shutdown)
led_dat->cdev.flags |= LED_RETAIN_AT_SHUTDOWN;
ret = gpiod_direction_output(led_dat->gpiod, state);
if (ret < 0)
return ret;
if (template->name) {
led_dat->cdev.name = template->name;
ret = devm_led_classdev_register(parent, &led_dat->cdev);
} else {
init_data.fwnode = fwnode;
ret = devm_led_classdev_register_ext(parent, &led_dat->cdev,
&init_data);
}
return ret;
}
struct gpio_leds_priv {
int num_leds;
struct gpio_led_data leds[];
};
static struct gpio_leds_priv *gpio_leds_create(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct fwnode_handle *child;
struct gpio_leds_priv *priv;
int count, ret;
count = device_get_child_node_count(dev);
if (!count)
return ERR_PTR(-ENODEV);
priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL);
if (!priv)
return ERR_PTR(-ENOMEM);
device_for_each_child_node(dev, child) {
struct gpio_led_data *led_dat = &priv->leds[priv->num_leds];
struct gpio_led led = {};
const char *state = NULL;
/*
* Acquire gpiod from DT with uninitialized label, which
* will be updated after LED class device is registered,
* Only then the final LED name is known.
*/
led.gpiod = devm_fwnode_get_gpiod_from_child(dev, NULL, child,
GPIOD_ASIS,
NULL);
if (IS_ERR(led.gpiod)) {
fwnode_handle_put(child);
return ERR_CAST(led.gpiod);
}
led_dat->gpiod = led.gpiod;
if (!fwnode_property_read_string(child, "default-state",
&state)) {
leds: Add options to have GPIO LEDs start on or keep their state There already is a "default-on" trigger but there are problems with it. For one, it's a inefficient way to do it and requires led trigger support to be compiled in. But the real reason is that is produces a glitch on the LED. The GPIO is allocate with the LED *off*, then *later* when the trigger runs it is turned back on. If the LED was already on via the GPIO's reset default or action of the firmware, this produces a glitch where the LED goes from on to off to on. While normally this is fast enough that it wouldn't be noticeable to a human observer, there are still serious problems. One is that there may be something else on the GPIO line, like a hardware alarm or watchdog, that is fast enough to notice the glitch. Another is that the kernel may panic before the LED is turned back on, thus hanging with the LED in the wrong state. This is not just speculation, but actually happened to me with an embedded system that has an LED which should turn off when the kernel finishes booting, which was left in the incorrect state due to a bug in the OF LED binding code. We also let GPIO LEDs get their initial value from whatever the current state of the GPIO line is. On some systems the LEDs are put into some state by the firmware or hardware before Linux boots, and it is desired to have them keep this state which is otherwise unknown to Linux. This requires that the underlying GPIO driver support reading the value of output GPIOs. Some drivers support this and some do not. The platform device binding gains a field in the platform data "default_state" that controls this. There are three constants defined to select from on, off, or keeping the current state. The OpenFirmware binding uses a property named "default-state" that can be set to "on", "off", or "keep". The default if the property isn't present is off. Signed-off-by: Trent Piepho <xyzzy@speakeasy.org> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-05-13 05:33:12 +07:00
if (!strcmp(state, "keep"))
led.default_state = LEDS_GPIO_DEFSTATE_KEEP;
else if (!strcmp(state, "on"))
leds: Add options to have GPIO LEDs start on or keep their state There already is a "default-on" trigger but there are problems with it. For one, it's a inefficient way to do it and requires led trigger support to be compiled in. But the real reason is that is produces a glitch on the LED. The GPIO is allocate with the LED *off*, then *later* when the trigger runs it is turned back on. If the LED was already on via the GPIO's reset default or action of the firmware, this produces a glitch where the LED goes from on to off to on. While normally this is fast enough that it wouldn't be noticeable to a human observer, there are still serious problems. One is that there may be something else on the GPIO line, like a hardware alarm or watchdog, that is fast enough to notice the glitch. Another is that the kernel may panic before the LED is turned back on, thus hanging with the LED in the wrong state. This is not just speculation, but actually happened to me with an embedded system that has an LED which should turn off when the kernel finishes booting, which was left in the incorrect state due to a bug in the OF LED binding code. We also let GPIO LEDs get their initial value from whatever the current state of the GPIO line is. On some systems the LEDs are put into some state by the firmware or hardware before Linux boots, and it is desired to have them keep this state which is otherwise unknown to Linux. This requires that the underlying GPIO driver support reading the value of output GPIOs. Some drivers support this and some do not. The platform device binding gains a field in the platform data "default_state" that controls this. There are three constants defined to select from on, off, or keeping the current state. The OpenFirmware binding uses a property named "default-state" that can be set to "on", "off", or "keep". The default if the property isn't present is off. Signed-off-by: Trent Piepho <xyzzy@speakeasy.org> Acked-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Sean MacLennan <smaclennan@pikatech.com> Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>
2009-05-13 05:33:12 +07:00
led.default_state = LEDS_GPIO_DEFSTATE_ON;
else
led.default_state = LEDS_GPIO_DEFSTATE_OFF;
}
if (fwnode_property_present(child, "retain-state-suspended"))
led.retain_state_suspended = 1;
if (fwnode_property_present(child, "retain-state-shutdown"))
led.retain_state_shutdown = 1;
if (fwnode_property_present(child, "panic-indicator"))
led.panic_indicator = 1;
ret = create_gpio_led(&led, led_dat, dev, child, NULL);
if (ret < 0) {
fwnode_handle_put(child);
return ERR_PTR(ret);
}
/* Set gpiod label to match the corresponding LED name. */
gpiod_set_consumer_name(led_dat->gpiod,
led_dat->cdev.dev->kobj.name);
priv->num_leds++;
}
return priv;
}
static const struct of_device_id of_gpio_leds_match[] = {
{ .compatible = "gpio-leds", },
{},
};
MODULE_DEVICE_TABLE(of, of_gpio_leds_match);
static struct gpio_desc *gpio_led_get_gpiod(struct device *dev, int idx,
const struct gpio_led *template)
{
struct gpio_desc *gpiod;
unsigned long flags = GPIOF_OUT_INIT_LOW;
int ret;
/*
* This means the LED does not come from the device tree
* or ACPI, so let's try just getting it by index from the
* device, this will hit the board file, if any and get
* the GPIO from there.
*/
gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOD_OUT_LOW);
if (!IS_ERR(gpiod)) {
gpiod_set_consumer_name(gpiod, template->name);
return gpiod;
}
if (PTR_ERR(gpiod) != -ENOENT)
return gpiod;
/*
* This is the legacy code path for platform code that
* still uses GPIO numbers. Ultimately we would like to get
* rid of this block completely.
*/
/* skip leds that aren't available */
if (!gpio_is_valid(template->gpio))
return ERR_PTR(-ENOENT);
if (template->active_low)
flags |= GPIOF_ACTIVE_LOW;
ret = devm_gpio_request_one(dev, template->gpio, flags,
template->name);
if (ret < 0)
return ERR_PTR(ret);
gpiod = gpio_to_desc(template->gpio);
if (!gpiod)
return ERR_PTR(-EINVAL);
return gpiod;
}
static int gpio_led_probe(struct platform_device *pdev)
{
struct gpio_led_platform_data *pdata = dev_get_platdata(&pdev->dev);
struct gpio_leds_priv *priv;
int i, ret = 0;
if (pdata && pdata->num_leds) {
priv = devm_kzalloc(&pdev->dev, struct_size(priv, leds, pdata->num_leds),
GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->num_leds = pdata->num_leds;
for (i = 0; i < priv->num_leds; i++) {
const struct gpio_led *template = &pdata->leds[i];
struct gpio_led_data *led_dat = &priv->leds[i];
if (template->gpiod)
led_dat->gpiod = template->gpiod;
else
led_dat->gpiod =
gpio_led_get_gpiod(&pdev->dev,
i, template);
if (IS_ERR(led_dat->gpiod)) {
dev_info(&pdev->dev, "Skipping unavailable LED gpio %d (%s)\n",
template->gpio, template->name);
continue;
}
ret = create_gpio_led(template, led_dat,
&pdev->dev, NULL,
pdata->gpio_blink_set);
if (ret < 0)
return ret;
}
} else {
priv = gpio_leds_create(pdev);
if (IS_ERR(priv))
return PTR_ERR(priv);
}
platform_set_drvdata(pdev, priv);
return 0;
}
static void gpio_led_shutdown(struct platform_device *pdev)
{
struct gpio_leds_priv *priv = platform_get_drvdata(pdev);
int i;
for (i = 0; i < priv->num_leds; i++) {
struct gpio_led_data *led = &priv->leds[i];
if (!(led->cdev.flags & LED_RETAIN_AT_SHUTDOWN))
gpio_led_set(&led->cdev, LED_OFF);
}
}
static struct platform_driver gpio_led_driver = {
.probe = gpio_led_probe,
.shutdown = gpio_led_shutdown,
.driver = {
.name = "leds-gpio",
.of_match_table = of_gpio_leds_match,
},
};
module_platform_driver(gpio_led_driver);
MODULE_AUTHOR("Raphael Assenat <raph@8d.com>, Trent Piepho <tpiepho@freescale.com>");
MODULE_DESCRIPTION("GPIO LED driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:leds-gpio");