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-rw-r--r--fs/debugfs/file.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c
index 90f76575c056..ea62afa4fd57 100644
--- a/fs/debugfs/file.c
+++ b/fs/debugfs/file.c
@@ -15,9 +15,11 @@
15 15
16#include <linux/module.h> 16#include <linux/module.h>
17#include <linux/fs.h> 17#include <linux/fs.h>
18#include <linux/seq_file.h>
18#include <linux/pagemap.h> 19#include <linux/pagemap.h>
19#include <linux/namei.h> 20#include <linux/namei.h>
20#include <linux/debugfs.h> 21#include <linux/debugfs.h>
22#include <linux/io.h>
21 23
22static ssize_t default_read_file(struct file *file, char __user *buf, 24static ssize_t default_read_file(struct file *file, char __user *buf,
23 size_t count, loff_t *ppos) 25 size_t count, loff_t *ppos)
@@ -525,3 +527,96 @@ struct dentry *debugfs_create_blob(const char *name, mode_t mode,
525 return debugfs_create_file(name, mode, parent, blob, &fops_blob); 527 return debugfs_create_file(name, mode, parent, blob, &fops_blob);
526} 528}
527EXPORT_SYMBOL_GPL(debugfs_create_blob); 529EXPORT_SYMBOL_GPL(debugfs_create_blob);
530
531#ifdef CONFIG_HAS_IOMEM
532
533/*
534 * The regset32 stuff is used to print 32-bit registers using the
535 * seq_file utilities. We offer printing a register set in an already-opened
536 * sequential file or create a debugfs file that only prints a regset32.
537 */
538
539/**
540 * debugfs_print_regs32 - use seq_print to describe a set of registers
541 * @s: the seq_file structure being used to generate output
542 * @regs: an array if struct debugfs_reg32 structures
543 * @mregs: the length of the above array
544 * @base: the base address to be used in reading the registers
545 * @prefix: a string to be prefixed to every output line
546 *
547 * This function outputs a text block describing the current values of
548 * some 32-bit hardware registers. It is meant to be used within debugfs
549 * files based on seq_file that need to show registers, intermixed with other
550 * information. The prefix argument may be used to specify a leading string,
551 * because some peripherals have several blocks of identical registers,
552 * for example configuration of dma channels
553 */
554int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
555 int nregs, void __iomem *base, char *prefix)
556{
557 int i, ret = 0;
558
559 for (i = 0; i < nregs; i++, regs++) {
560 if (prefix)
561 ret += seq_printf(s, "%s", prefix);
562 ret += seq_printf(s, "%s = 0x%08x\n", regs->name,
563 readl(base + regs->offset));
564 }
565 return ret;
566}
567EXPORT_SYMBOL_GPL(debugfs_print_regs32);
568
569static int debugfs_show_regset32(struct seq_file *s, void *data)
570{
571 struct debugfs_regset32 *regset = s->private;
572
573 debugfs_print_regs32(s, regset->regs, regset->nregs, regset->base, "");
574 return 0;
575}
576
577static int debugfs_open_regset32(struct inode *inode, struct file *file)
578{
579 return single_open(file, debugfs_show_regset32, inode->i_private);
580}
581
582static const struct file_operations fops_regset32 = {
583 .open = debugfs_open_regset32,
584 .read = seq_read,
585 .llseek = seq_lseek,
586 .release = single_release,
587};
588
589/**
590 * debugfs_create_regset32 - create a debugfs file that returns register values
591 * @name: a pointer to a string containing the name of the file to create.
592 * @mode: the permission that the file should have
593 * @parent: a pointer to the parent dentry for this file. This should be a
594 * directory dentry if set. If this parameter is %NULL, then the
595 * file will be created in the root of the debugfs filesystem.
596 * @regset: a pointer to a struct debugfs_regset32, which contains a pointer
597 * to an array of register definitions, the array size and the base
598 * address where the register bank is to be found.
599 *
600 * This function creates a file in debugfs with the given name that reports
601 * the names and values of a set of 32-bit registers. If the @mode variable
602 * is so set it can be read from. Writing is not supported.
603 *
604 * This function will return a pointer to a dentry if it succeeds. This
605 * pointer must be passed to the debugfs_remove() function when the file is
606 * to be removed (no automatic cleanup happens if your module is unloaded,
607 * you are responsible here.) If an error occurs, %NULL will be returned.
608 *
609 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
610 * returned. It is not wise to check for this value, but rather, check for
611 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
612 * code.
613 */
614struct dentry *debugfs_create_regset32(const char *name, mode_t mode,
615 struct dentry *parent,
616 struct debugfs_regset32 *regset)
617{
618 return debugfs_create_file(name, mode, parent, regset, &fops_regset32);
619}
620EXPORT_SYMBOL_GPL(debugfs_create_regset32);
621
622#endif /* CONFIG_HAS_IOMEM */