diff options
Diffstat (limited to 'drivers/base/regmap/regmap-debugfs.c')
| -rw-r--r-- | drivers/base/regmap/regmap-debugfs.c | 335 |
1 files changed, 312 insertions, 23 deletions
diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c index bb1ff175b96..45d812c0ea7 100644 --- a/drivers/base/regmap/regmap-debugfs.c +++ b/drivers/base/regmap/regmap-debugfs.c @@ -15,10 +15,19 @@ #include <linux/debugfs.h> #include <linux/uaccess.h> #include <linux/device.h> +#include <linux/list.h> #include "internal.h" +struct regmap_debugfs_node { + struct regmap *map; + const char *name; + struct list_head link; +}; + static struct dentry *regmap_debugfs_root; +static LIST_HEAD(regmap_debugfs_early_list); +static DEFINE_MUTEX(regmap_debugfs_early_lock); /* Calculate the length of a fixed format */ static size_t regmap_calc_reg_len(int max_val, char *buf, size_t buf_size) @@ -56,17 +65,133 @@ static const struct file_operations regmap_name_fops = { .llseek = default_llseek, }; -static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf, - size_t count, loff_t *ppos) +static void regmap_debugfs_free_dump_cache(struct regmap *map) { - int reg_len, val_len, tot_len; - size_t buf_pos = 0; + struct regmap_debugfs_off_cache *c; + + while (!list_empty(&map->debugfs_off_cache)) { + c = list_first_entry(&map->debugfs_off_cache, + struct regmap_debugfs_off_cache, + list); + list_del(&c->list); + kfree(c); + } +} + +/* + * Work out where the start offset maps into register numbers, bearing + * in mind that we suppress hidden registers. + */ +static unsigned int regmap_debugfs_get_dump_start(struct regmap *map, + unsigned int base, + loff_t from, + loff_t *pos) +{ + struct regmap_debugfs_off_cache *c = NULL; loff_t p = 0; + unsigned int i, ret; + unsigned int fpos_offset; + unsigned int reg_offset; + + /* Suppress the cache if we're using a subrange */ + if (base) + return base; + + /* + * If we don't have a cache build one so we don't have to do a + * linear scan each time. + */ + mutex_lock(&map->cache_lock); + i = base; + if (list_empty(&map->debugfs_off_cache)) { + for (; i <= map->max_register; i += map->reg_stride) { + /* Skip unprinted registers, closing off cache entry */ + if (!regmap_readable(map, i) || + regmap_precious(map, i)) { + if (c) { + c->max = p - 1; + c->max_reg = i - map->reg_stride; + list_add_tail(&c->list, + &map->debugfs_off_cache); + c = NULL; + } + + continue; + } + + /* No cache entry? Start a new one */ + if (!c) { + c = kzalloc(sizeof(*c), GFP_KERNEL); + if (!c) { + regmap_debugfs_free_dump_cache(map); + mutex_unlock(&map->cache_lock); + return base; + } + c->min = p; + c->base_reg = i; + } + + p += map->debugfs_tot_len; + } + } + + /* Close the last entry off if we didn't scan beyond it */ + if (c) { + c->max = p - 1; + c->max_reg = i - map->reg_stride; + list_add_tail(&c->list, + &map->debugfs_off_cache); + } + + /* + * This should never happen; we return above if we fail to + * allocate and we should never be in this code if there are + * no registers at all. + */ + WARN_ON(list_empty(&map->debugfs_off_cache)); + ret = base; + + /* Find the relevant block:offset */ + list_for_each_entry(c, &map->debugfs_off_cache, list) { + if (from >= c->min && from <= c->max) { + fpos_offset = from - c->min; + reg_offset = fpos_offset / map->debugfs_tot_len; + *pos = c->min + (reg_offset * map->debugfs_tot_len); + mutex_unlock(&map->cache_lock); + return c->base_reg + (reg_offset * map->reg_stride); + } + + *pos = c->max; + ret = c->max_reg; + } + mutex_unlock(&map->cache_lock); + + return ret; +} + +static inline void regmap_calc_tot_len(struct regmap *map, + void *buf, size_t count) +{ + /* Calculate the length of a fixed format */ + if (!map->debugfs_tot_len) { + map->debugfs_reg_len = regmap_calc_reg_len(map->max_register, + buf, count); + map->debugfs_val_len = 2 * map->format.val_bytes; + map->debugfs_tot_len = map->debugfs_reg_len + + map->debugfs_val_len + 3; /* : \n */ + } +} + +static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from, + unsigned int to, char __user *user_buf, + size_t count, loff_t *ppos) +{ + size_t buf_pos = 0; + loff_t p = *ppos; ssize_t ret; int i; - struct regmap *map = file->private_data; char *buf; - unsigned int val; + unsigned int val, start_reg; if (*ppos < 0 || !count) return -EINVAL; @@ -75,12 +200,12 @@ static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf, 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 */ + regmap_calc_tot_len(map, buf, count); - for (i = 0; i <= map->max_register; i += map->reg_stride) { + /* Work out which register we're starting at */ + start_reg = regmap_debugfs_get_dump_start(map, from, *ppos, &p); + + for (i = start_reg; i <= to; i += map->reg_stride) { if (!regmap_readable(map, i)) continue; @@ -90,26 +215,27 @@ static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf, /* 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) + if (buf_pos + map->debugfs_tot_len > count) break; /* Format the register */ snprintf(buf + buf_pos, count - buf_pos, "%.*x: ", - reg_len, i); - buf_pos += reg_len + 2; + map->debugfs_reg_len, i - from); + buf_pos += map->debugfs_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); + "%.*x", map->debugfs_val_len, val); else - memset(buf + buf_pos, 'X', val_len); + memset(buf + buf_pos, 'X', + map->debugfs_val_len); buf_pos += 2 * map->format.val_bytes; buf[buf_pos++] = '\n'; } - p += tot_len; + p += map->debugfs_tot_len; } ret = buf_pos; @@ -126,6 +252,15 @@ out: return ret; } +static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct regmap *map = file->private_data; + + return regmap_read_debugfs(map, 0, map->max_register, user_buf, + count, ppos); +} + #undef REGMAP_ALLOW_WRITE_DEBUGFS #ifdef REGMAP_ALLOW_WRITE_DEBUGFS /* @@ -143,6 +278,7 @@ static ssize_t regmap_map_write_file(struct file *file, char *start = buf; unsigned long reg, value; struct regmap *map = file->private_data; + int ret; buf_size = min(count, (sizeof(buf)-1)); if (copy_from_user(buf, user_buf, buf_size)) @@ -154,13 +290,15 @@ static ssize_t regmap_map_write_file(struct file *file, reg = simple_strtoul(start, &start, 16); while (*start == ' ') start++; - if (strict_strtoul(start, 16, &value)) + if (kstrtoul(start, 16, &value)) return -EINVAL; /* Userspace has been fiddling around behind the kernel's back */ - add_taint(TAINT_USER); + add_taint(TAINT_USER, LOCKDEP_STILL_OK); - regmap_write(map, reg, value); + ret = regmap_write(map, reg, value); + if (ret < 0) + return ret; return buf_size; } #else @@ -174,6 +312,95 @@ static const struct file_operations regmap_map_fops = { .llseek = default_llseek, }; +static ssize_t regmap_range_read_file(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct regmap_range_node *range = file->private_data; + struct regmap *map = range->map; + + return regmap_read_debugfs(map, range->range_min, range->range_max, + user_buf, count, ppos); +} + +static const struct file_operations regmap_range_fops = { + .open = simple_open, + .read = regmap_range_read_file, + .llseek = default_llseek, +}; + +static ssize_t regmap_reg_ranges_read_file(struct file *file, + char __user *user_buf, size_t count, + loff_t *ppos) +{ + struct regmap *map = file->private_data; + struct regmap_debugfs_off_cache *c; + loff_t p = 0; + size_t buf_pos = 0; + char *buf; + char *entry; + int ret; + + if (*ppos < 0 || !count) + return -EINVAL; + + buf = kmalloc(count, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + entry = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!entry) { + kfree(buf); + return -ENOMEM; + } + + /* While we are at it, build the register dump cache + * now so the read() operation on the `registers' file + * can benefit from using the cache. We do not care + * about the file position information that is contained + * in the cache, just about the actual register blocks */ + regmap_calc_tot_len(map, buf, count); + regmap_debugfs_get_dump_start(map, 0, *ppos, &p); + + /* Reset file pointer as the fixed-format of the `registers' + * file is not compatible with the `range' file */ + p = 0; + mutex_lock(&map->cache_lock); + list_for_each_entry(c, &map->debugfs_off_cache, list) { + snprintf(entry, PAGE_SIZE, "%x-%x", + c->base_reg, c->max_reg); + if (p >= *ppos) { + if (buf_pos + 1 + strlen(entry) > count) + break; + snprintf(buf + buf_pos, count - buf_pos, + "%s", entry); + buf_pos += strlen(entry); + buf[buf_pos] = '\n'; + buf_pos++; + } + p += strlen(entry) + 1; + } + mutex_unlock(&map->cache_lock); + + kfree(entry); + ret = buf_pos; + + if (copy_to_user(user_buf, buf, buf_pos)) { + ret = -EFAULT; + goto out_buf; + } + + *ppos += buf_pos; +out_buf: + kfree(buf); + return ret; +} + +static const struct file_operations regmap_reg_ranges_fops = { + .open = simple_open, + .read = regmap_reg_ranges_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) @@ -244,6 +471,26 @@ static const struct file_operations regmap_access_fops = { void regmap_debugfs_init(struct regmap *map, const char *name) { + struct rb_node *next; + struct regmap_range_node *range_node; + + /* If we don't have the debugfs root yet, postpone init */ + if (!regmap_debugfs_root) { + struct regmap_debugfs_node *node; + node = kzalloc(sizeof(*node), GFP_KERNEL); + if (!node) + return; + node->map = map; + node->name = name; + mutex_lock(®map_debugfs_early_lock); + list_add(&node->link, ®map_debugfs_early_list); + mutex_unlock(®map_debugfs_early_lock); + return; + } + + INIT_LIST_HEAD(&map->debugfs_off_cache); + mutex_init(&map->cache_lock); + if (name) { map->debugfs_name = kasprintf(GFP_KERNEL, "%s-%s", dev_name(map->dev), name); @@ -261,7 +508,10 @@ void regmap_debugfs_init(struct regmap *map, const char *name) debugfs_create_file("name", 0400, map->debugfs, map, ®map_name_fops); - if (map->max_register) { + debugfs_create_file("range", 0400, map->debugfs, + map, ®map_reg_ranges_fops); + + if (map->max_register || regmap_readable(map, 0)) { debugfs_create_file("registers", 0400, map->debugfs, map, ®map_map_fops); debugfs_create_file("access", 0400, map->debugfs, @@ -276,19 +526,58 @@ void regmap_debugfs_init(struct regmap *map, const char *name) debugfs_create_bool("cache_bypass", 0400, map->debugfs, &map->cache_bypass); } + + next = rb_first(&map->range_tree); + while (next) { + range_node = rb_entry(next, struct regmap_range_node, node); + + if (range_node->name) + debugfs_create_file(range_node->name, 0400, + map->debugfs, range_node, + ®map_range_fops); + + next = rb_next(&range_node->node); + } } void regmap_debugfs_exit(struct regmap *map) { - debugfs_remove_recursive(map->debugfs); - kfree(map->debugfs_name); + if (map->debugfs) { + debugfs_remove_recursive(map->debugfs); + mutex_lock(&map->cache_lock); + regmap_debugfs_free_dump_cache(map); + mutex_unlock(&map->cache_lock); + kfree(map->debugfs_name); + } else { + struct regmap_debugfs_node *node, *tmp; + + mutex_lock(®map_debugfs_early_lock); + list_for_each_entry_safe(node, tmp, ®map_debugfs_early_list, + link) { + if (node->map == map) { + list_del(&node->link); + kfree(node); + } + } + mutex_unlock(®map_debugfs_early_lock); + } } void regmap_debugfs_initcall(void) { + struct regmap_debugfs_node *node, *tmp; + regmap_debugfs_root = debugfs_create_dir("regmap", NULL); if (!regmap_debugfs_root) { pr_warn("regmap: Failed to create debugfs root\n"); return; } + + mutex_lock(®map_debugfs_early_lock); + list_for_each_entry_safe(node, tmp, ®map_debugfs_early_list, link) { + regmap_debugfs_init(node->map, node->name); + list_del(&node->link); + kfree(node); + } + mutex_unlock(®map_debugfs_early_lock); } |