diff options
Diffstat (limited to 'drivers/base/regmap/regmap-debugfs.c')
| -rw-r--r-- | drivers/base/regmap/regmap-debugfs.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c new file mode 100644 index 00000000000..6f397476e27 --- /dev/null +++ b/drivers/base/regmap/regmap-debugfs.c @@ -0,0 +1,209 @@ +/* + * Register map access API - debugfs + * + * Copyright 2011 Wolfson Microelectronics plc + * + * Author: Mark Brown <broonie@opensource.wolfsonmicro.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> + +#include "internal.h" + +static struct dentry *regmap_debugfs_root; + +/* Calculate the length of a fixed format */ +static size_t regmap_calc_reg_len(int max_val, char *buf, size_t buf_size) +{ + snprintf(buf, buf_size, "%x", max_val); + return strlen(buf); +} + +static int regmap_open_file(struct inode *inode, struct file *file) +{ + file->private_data = inode->i_private; + return 0; +} + +static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + int reg_len, val_len, tot_len; + size_t buf_pos = 0; + loff_t p = 0; + ssize_t ret; + int i; + struct regmap *map = file->private_data; + char *buf; + unsigned int val; + + if (*ppos < 0 || !count) + return -EINVAL; + + buf = kmalloc(count, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + /* Calculate the length of a fixed format */ + reg_len = regmap_calc_reg_len(map->max_register, buf, count); + val_len = 2 * map->format.val_bytes; + tot_len = reg_len + val_len + 3; /* : \n */ + + for (i = 0; i < map->max_register + 1; i++) { + if (!regmap_readable(map, i)) + continue; + + if (regmap_precious(map, i)) + continue; + + /* If we're in the region the user is trying to read */ + if (p >= *ppos) { + /* ...but not beyond it */ + if (buf_pos >= count - 1 - tot_len) + break; + + /* Format the register */ + snprintf(buf + buf_pos, count - buf_pos, "%.*x: ", + reg_len, i); + buf_pos += reg_len + 2; + + /* Format the value, write all X if we can't read */ + ret = regmap_read(map, i, &val); + if (ret == 0) + snprintf(buf + buf_pos, count - buf_pos, + "%.*x", val_len, val); + else + memset(buf + buf_pos, 'X', val_len); + buf_pos += 2 * map->format.val_bytes; + + buf[buf_pos++] = '\n'; + } + p += tot_len; + } + + ret = buf_pos; + + if (copy_to_user(user_buf, buf, buf_pos)) { + ret = -EFAULT; + goto out; + } + + *ppos += buf_pos; + +out: + kfree(buf); + return ret; +} + +static const struct file_operations regmap_map_fops = { + .open = regmap_open_file, + .read = regmap_map_read_file, + .llseek = default_llseek, +}; + +static ssize_t regmap_access_read_file(struct file *file, + char __user *user_buf, size_t count, + loff_t *ppos) +{ + int reg_len, tot_len; + size_t buf_pos = 0; + loff_t p = 0; + ssize_t ret; + int i; + struct regmap *map = file->private_data; + char *buf; + + if (*ppos < 0 || !count) + return -EINVAL; + + buf = kmalloc(count, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + /* Calculate the length of a fixed format */ + reg_len = regmap_calc_reg_len(map->max_register, buf, count); + tot_len = reg_len + 10; /* ': R W V P\n' */ + + for (i = 0; i < map->max_register + 1; i++) { + /* Ignore registers which are neither readable nor writable */ + if (!regmap_readable(map, i) && !regmap_writeable(map, i)) + continue; + + /* If we're in the region the user is trying to read */ + if (p >= *ppos) { + /* ...but not beyond it */ + if (buf_pos >= count - 1 - tot_len) + break; + + /* Format the register */ + snprintf(buf + buf_pos, count - buf_pos, + "%.*x: %c %c %c %c\n", + reg_len, i, + regmap_readable(map, i) ? 'y' : 'n', + regmap_writeable(map, i) ? 'y' : 'n', + regmap_volatile(map, i) ? 'y' : 'n', + regmap_precious(map, i) ? 'y' : 'n'); + + buf_pos += tot_len; + } + p += tot_len; + } + + ret = buf_pos; + + if (copy_to_user(user_buf, buf, buf_pos)) { + ret = -EFAULT; + goto out; + } + + *ppos += buf_pos; + +out: + kfree(buf); + return ret; +} + +static const struct file_operations regmap_access_fops = { + .open = regmap_open_file, + .read = regmap_access_read_file, + .llseek = default_llseek, +}; + +void regmap_debugfs_init(struct regmap *map) +{ + map->debugfs = debugfs_create_dir(dev_name(map->dev), + regmap_debugfs_root); + if (!map->debugfs) { + dev_warn(map->dev, "Failed to create debugfs directory\n"); + return; + } + + if (map->max_register) { + debugfs_create_file("registers", 0400, map->debugfs, + map, ®map_map_fops); + debugfs_create_file("access", 0400, map->debugfs, + map, ®map_access_fops); + } +} + +void regmap_debugfs_exit(struct regmap *map) +{ + debugfs_remove_recursive(map->debugfs); +} + +void regmap_debugfs_initcall(void) +{ + regmap_debugfs_root = debugfs_create_dir("regmap", NULL); + if (!regmap_debugfs_root) { + pr_warn("regmap: Failed to create debugfs root\n"); + return; + } +} |