The Linux Manuals (man pages) document is an important part of Linux documents. Linux Manuals are organized as several sections. Each section has a group of commands for a specific area in Linux usage, administration or development.
clk_is_match – check if two clk’s point to the same hardware clock Synopsis bool clk_is_match(const struct clk * p, const struct clk * q); Arguments p clk compared against q q clk compared against p Description Returns true if the two struct clk pointers both point to the same hardware clock node. Put differently, returns true if struct clk…
clk_has_parent – check if a clock is a possible parent for another Synopsis bool clk_has_parent(struct clk * clk, struct clk * parent); Arguments clk clock source parent parent clock source Description This function can be used in drivers that need to check that a clock can be the parent of another without actually changing the parent. Returns true if…
clk_get_sys – get a clock based upon the device name Synopsis struct clk *clk_get_sys(const char *dev_id, const char *con_id); Arguments dev_id device name con_id connection ID Description Returns a struct clk corresponding to the clock producer, or valid IS_ERR condition containing errno. The implementation uses dev_id and con_id to determine the clock consumer, and thereby…
clk_get_rate – obtain the current clock rate (in Hz) for a clock source. This is only valid once the clock source has been enabled. Synopsis unsigned long clk_get_rate(struct clk *clk); Arguments clk clock source Copyright
clk_get_phase – return the phase shift of a clock signal Synopsis int clk_get_phase(struct clk *clk); Arguments clk clock signal source Description Returns the phase shift of a clock node in degrees, otherwise returns -EERROR. Copyright
clk_get_parent – get the parent clock source for this clock Synopsis struct clk *clk_get_parent(struct clk *clk); Arguments clk clock source Description Returns struct clk corresponding to parent clock source, or valid IS_ERR condition containing errno. Copyright
clk_get_accuracy – obtain the clock accuracy in ppb (parts per billion) for a clock source. Synopsis long clk_get_accuracy(struct clk *clk); Arguments clk clock source Description This gets the clock source accuracy expressed in ppb. A perfect clock returns 0. Copyright
clk_get – lookup and obtain a reference to a clock producer. Synopsis struct clk *clk_get(struct device *dev, const char *id); Arguments dev device for clock “consumer” id clock consumer ID Description Returns a struct clk corresponding to the clock producer, or valid IS_ERR condition containing errno. The implementation uses dev and id to determine the…
clk_enable – inform the system when the clock source should be running. Synopsis int clk_enable(struct clk *clk); Arguments clk clock source Description If the clock can not be enabled/disabled, this should return success. May be called from atomic contexts. Returns success (0) or negative errno. Copyright
clk_disable – inform the system when the clock source is no longer required. Synopsis void clk_disable(struct clk *clk); Arguments clk clock source Description Inform the system that a clock source is no longer required by a driver and may be shut down. May be called from atomic contexts. Implementation detail: if the clock source is…
clear_user – Zero a block of memory in user space. Synopsis unsigned long clear_user(void __user *to, unsigned long n); Arguments to Destination address, in user space. n Number of bytes to zero. Description Zero a block of memory in user space. Returns number of bytes that could not be cleared. On success, this will be…
clear_nlink – directly zero an inode’s link count Synopsis void clear_nlink(struct inode *inode); Arguments inode inode Description This is a low-level filesystem helper to replace any direct filesystem manipulation of i_nlink. See drop_nlink for why we care about i_nlink hitting zero. Copyright
clear_bit – Clears a bit in memory Synopsis void clear_bit(long nr, volatile unsigned long *addr); Arguments nr Bit to clear addr Address to start counting from Description clear_bit is atomic and may not be reordered. However, it does not contain a memory barrier, so if it is used for locking purposes, you should call smp_mb__before_atomic…
check_short_pattern – [GENERIC] check if a pattern is in the buffer Synopsis int check_short_pattern(uint8_t *buf, struct nand_bbt_descr *td); Arguments buf the buffer to search td search pattern descriptor Description Check for a pattern at the given place. Used to search bad block tables and good / bad block identifiers. Same as check_pattern, but no optional…
check_pattern – [GENERIC] check if a pattern is in the buffer Synopsis int check_pattern(uint8_t *buf, int len, int paglen, struct nand_bbt_descr *td); Arguments buf the buffer to search len the length of buffer to search paglen the pagelength td search pattern descriptor Description Check for a pattern at the given place. Used to search bad…
check_disk_size_change – checks for disk size change and adjusts bdev size. Synopsis void check_disk_size_change(struct gendisk *disk, struct block_device *bdev); Arguments disk struct gendisk to check bdev struct bdev to adjust. Description This routine checks to see if the bdev size does not match the disk size and adjusts it if it differs. Copyright
check_create – [GENERIC] create and write bbt(s) if necessary Synopsis int check_create(struct mtd_info *mtd, uint8_t *buf, struct nand_bbt_descr *bd); Arguments mtd MTD device structure buf temporary buffer bd descriptor for the good/bad block search pattern Description The function checks the results of the previous call to read_bbt and creates / updates the bbt(s) if necessary….
check_conflicting_open – see if the given dentry points to a file that has an existing open that would conflict with the desired lease. Synopsis int check_conflicting_open(const struct dentry *dentry, const long arg, int flags); Arguments dentry dentry to check arg type of lease that we’re trying to acquire flags current lock flags Description Check to…
change_bit – Toggle a bit in memory Synopsis void change_bit(long nr, volatile unsigned long *addr); Arguments nr Bit to change addr Address to start counting from Description change_bit is atomic and may not be reordered. Note that nr may be almost arbitrarily large; this function is not restricted to acting on a single-word quantity. Copyright
cdev_init – initialize a cdev structure Synopsis void cdev_init(struct cdev *cdev, const struct file_operations *fops); Arguments cdev the structure to initialize fops the file_operations for this device Description Initializes cdev, remembering fops, making it ready to add to the system with cdev_add. Copyright