linux-sg2042/include/linux/gpio.h

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
/* SPDX-License-Identifier: GPL-2.0 */
/*
* <linux/gpio.h>
*
* This is the LEGACY GPIO bulk include file, including legacy APIs. It is
* used for GPIO drivers still referencing the global GPIO numberspace,
* and should not be included in new code.
*
* If you're implementing a GPIO driver, only include <linux/gpio/driver.h>
* If you're implementing a GPIO consumer, only include <linux/gpio/consumer.h>
*/
#ifndef __LINUX_GPIO_H
#define __LINUX_GPIO_H
#include <linux/errno.h>
/* see Documentation/driver-api/gpio/legacy.rst */
/* make these flag values available regardless of GPIO kconfig options */
#define GPIOF_DIR_OUT (0 << 0)
#define GPIOF_DIR_IN (1 << 0)
#define GPIOF_INIT_LOW (0 << 1)
#define GPIOF_INIT_HIGH (1 << 1)
#define GPIOF_IN (GPIOF_DIR_IN)
#define GPIOF_OUT_INIT_LOW (GPIOF_DIR_OUT | GPIOF_INIT_LOW)
#define GPIOF_OUT_INIT_HIGH (GPIOF_DIR_OUT | GPIOF_INIT_HIGH)
/* Gpio pin is active-low */
#define GPIOF_ACTIVE_LOW (1 << 2)
/* Gpio pin is open drain */
#define GPIOF_OPEN_DRAIN (1 << 3)
/* Gpio pin is open source */
#define GPIOF_OPEN_SOURCE (1 << 4)
#define GPIOF_EXPORT (1 << 5)
#define GPIOF_EXPORT_CHANGEABLE (1 << 6)
#define GPIOF_EXPORT_DIR_FIXED (GPIOF_EXPORT)
#define GPIOF_EXPORT_DIR_CHANGEABLE (GPIOF_EXPORT | GPIOF_EXPORT_CHANGEABLE)
/**
* struct gpio - a structure describing a GPIO with configuration
* @gpio: the GPIO number
* @flags: GPIO configuration as specified by GPIOF_*
* @label: a literal description string of this GPIO
*/
struct gpio {
unsigned gpio;
unsigned long flags;
const char *label;
};
#ifdef CONFIG_GPIOLIB
#ifdef CONFIG_ARCH_HAVE_CUSTOM_GPIO_H
#include <asm/gpio.h>
#else
#include <asm-generic/gpio.h>
static inline int gpio_get_value(unsigned int gpio)
{
return __gpio_get_value(gpio);
}
static inline void gpio_set_value(unsigned int gpio, int value)
{
__gpio_set_value(gpio, value);
}
static inline int gpio_cansleep(unsigned int gpio)
{
return __gpio_cansleep(gpio);
}
static inline int gpio_to_irq(unsigned int gpio)
{
return __gpio_to_irq(gpio);
}
static inline int irq_to_gpio(unsigned int irq)
{
return -EINVAL;
}
#endif /* ! CONFIG_ARCH_HAVE_CUSTOM_GPIO_H */
/* CONFIG_GPIOLIB: bindings for managed devices that want to request gpios */
struct device;
int devm_gpio_request(struct device *dev, unsigned gpio, const char *label);
int devm_gpio_request_one(struct device *dev, unsigned gpio,
unsigned long flags, const char *label);
void devm_gpio_free(struct device *dev, unsigned int gpio);
#else /* ! CONFIG_GPIOLIB */
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/bug.h>
struct device;
struct gpio_chip;
static inline bool gpio_is_valid(int number)
{
return false;
}
static inline int gpio_request(unsigned gpio, const char *label)
{
return -ENOSYS;
}
static inline int gpio_request_one(unsigned gpio,
unsigned long flags, const char *label)
{
return -ENOSYS;
}
static inline int gpio_request_array(const struct gpio *array, size_t num)
{
return -ENOSYS;
}
static inline void gpio_free(unsigned gpio)
{
might_sleep();
/* GPIO can never have been requested */
WARN_ON(1);
}
static inline void gpio_free_array(const struct gpio *array, size_t num)
{
might_sleep();
/* GPIO can never have been requested */
WARN_ON(1);
}
static inline int gpio_direction_input(unsigned gpio)
{
return -ENOSYS;
}
static inline int gpio_direction_output(unsigned gpio, int value)
{
return -ENOSYS;
}
2010-05-27 05:42:23 +08:00
static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
{
return -ENOSYS;
}
static inline int gpio_get_value(unsigned gpio)
{
/* GPIO can never have been requested or set as {in,out}put */
WARN_ON(1);
return 0;
}
static inline void gpio_set_value(unsigned gpio, int value)
{
/* GPIO can never have been requested or set as output */
WARN_ON(1);
}
static inline int gpio_cansleep(unsigned gpio)
{
/* GPIO can never have been requested or set as {in,out}put */
WARN_ON(1);
return 0;
}
static inline int gpio_get_value_cansleep(unsigned gpio)
{
/* GPIO can never have been requested or set as {in,out}put */
WARN_ON(1);
return 0;
}
static inline void gpio_set_value_cansleep(unsigned gpio, int value)
{
/* GPIO can never have been requested or set as output */
WARN_ON(1);
}
gpio: sysfs interface This adds a simple sysfs interface for GPIOs. /sys/class/gpio /export ... asks the kernel to export a GPIO to userspace /unexport ... to return a GPIO to the kernel /gpioN ... for each exported GPIO #N /value ... always readable, writes fail for input GPIOs /direction ... r/w as: in, out (default low); write high, low /gpiochipN ... for each gpiochip; #N is its first GPIO /base ... (r/o) same as N /label ... (r/o) descriptive, not necessarily unique /ngpio ... (r/o) number of GPIOs; numbered N .. N+(ngpio - 1) GPIOs claimed by kernel code may be exported by its owner using a new gpio_export() call, which should be most useful for driver debugging. Such exports may optionally be done without a "direction" attribute. Userspace may ask to take over a GPIO by writing to a sysfs control file, helping to cope with incomplete board support or other "one-off" requirements that don't merit full kernel support: echo 23 > /sys/class/gpio/export ... will gpio_request(23, "sysfs") and gpio_export(23); use /sys/class/gpio/gpio-23/direction to (re)configure it, when that GPIO can be used as both input and output. echo 23 > /sys/class/gpio/unexport ... will gpio_free(23), when it was exported as above The extra D-space footprint is a few hundred bytes, except for the sysfs resources associated with each exported GPIO. The additional I-space footprint is about two thirds of the current size of gpiolib (!). Since no /dev node creation is involved, no "udev" support is needed. Related changes: * This adds a device pointer to "struct gpio_chip". When GPIO providers initialize that, sysfs gpio class devices become children of that device instead of being "virtual" devices. * The (few) gpio_chip providers which have such a device node have been updated. * Some gpio_chip drivers also needed to update their module "owner" field ... for which missing kerneldoc was added. * Some gpio_chips don't support input GPIOs. Those GPIOs are now flagged appropriately when the chip is registered. Based on previous patches, and discussion both on and off LKML. A Documentation/ABI/testing/sysfs-gpio update is ready to submit once this merges to mainline. [akpm@linux-foundation.org: a few maintenance build fixes] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 16:46:07 +08:00
static inline int gpio_export(unsigned gpio, bool direction_may_change)
{
/* GPIO can never have been requested or set as {in,out}put */
WARN_ON(1);
return -EINVAL;
}
static inline int gpio_export_link(struct device *dev, const char *name,
unsigned gpio)
{
/* GPIO can never have been exported */
WARN_ON(1);
return -EINVAL;
}
gpio: sysfs interface This adds a simple sysfs interface for GPIOs. /sys/class/gpio /export ... asks the kernel to export a GPIO to userspace /unexport ... to return a GPIO to the kernel /gpioN ... for each exported GPIO #N /value ... always readable, writes fail for input GPIOs /direction ... r/w as: in, out (default low); write high, low /gpiochipN ... for each gpiochip; #N is its first GPIO /base ... (r/o) same as N /label ... (r/o) descriptive, not necessarily unique /ngpio ... (r/o) number of GPIOs; numbered N .. N+(ngpio - 1) GPIOs claimed by kernel code may be exported by its owner using a new gpio_export() call, which should be most useful for driver debugging. Such exports may optionally be done without a "direction" attribute. Userspace may ask to take over a GPIO by writing to a sysfs control file, helping to cope with incomplete board support or other "one-off" requirements that don't merit full kernel support: echo 23 > /sys/class/gpio/export ... will gpio_request(23, "sysfs") and gpio_export(23); use /sys/class/gpio/gpio-23/direction to (re)configure it, when that GPIO can be used as both input and output. echo 23 > /sys/class/gpio/unexport ... will gpio_free(23), when it was exported as above The extra D-space footprint is a few hundred bytes, except for the sysfs resources associated with each exported GPIO. The additional I-space footprint is about two thirds of the current size of gpiolib (!). Since no /dev node creation is involved, no "udev" support is needed. Related changes: * This adds a device pointer to "struct gpio_chip". When GPIO providers initialize that, sysfs gpio class devices become children of that device instead of being "virtual" devices. * The (few) gpio_chip providers which have such a device node have been updated. * Some gpio_chip drivers also needed to update their module "owner" field ... for which missing kerneldoc was added. * Some gpio_chips don't support input GPIOs. Those GPIOs are now flagged appropriately when the chip is registered. Based on previous patches, and discussion both on and off LKML. A Documentation/ABI/testing/sysfs-gpio update is ready to submit once this merges to mainline. [akpm@linux-foundation.org: a few maintenance build fixes] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25 16:46:07 +08:00
static inline void gpio_unexport(unsigned gpio)
{
/* GPIO can never have been exported */
WARN_ON(1);
}
static inline int gpio_to_irq(unsigned gpio)
{
/* GPIO can never have been requested or set as input */
WARN_ON(1);
return -EINVAL;
}
static inline int irq_to_gpio(unsigned irq)
{
/* irq can never have been returned from gpio_to_irq() */
WARN_ON(1);
return -EINVAL;
}
static inline int devm_gpio_request(struct device *dev, unsigned gpio,
const char *label)
{
WARN_ON(1);
return -EINVAL;
}
static inline int devm_gpio_request_one(struct device *dev, unsigned gpio,
unsigned long flags, const char *label)
{
WARN_ON(1);
return -EINVAL;
}
static inline void devm_gpio_free(struct device *dev, unsigned int gpio)
{
WARN_ON(1);
}
#endif /* ! CONFIG_GPIOLIB */
#endif /* __LINUX_GPIO_H */