regmap: debugfs: Optimize seeking within blocks of registers

Optimize this so that we can better guess where to start scanning
from.  We know the length of the register field format, therefore
given the file pointer position align to the nearest register
field and scan from there onwards.  We round down in this calculation
and we let the rest of the code figure out where to start scanning
from.

Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/drivers/base/regmap/regmap-debugfs.c b/drivers/base/regmap/regmap-debugfs.c
index 3fade1ceaf151ccc16dc3116e0bda74047246f75..246f459e91708008f4ca4fe539a72e3cf7944374 100644 (file)
--- a/drivers/base/regmap/regmap-debugfs.c
+++ b/drivers/base/regmap/regmap-debugfs.c
@@ -139,15 +139,17 @@ static unsigned int regmap_debugfs_get_dump_start(struct regmap *map,
        WARN_ON(list_empty(&map->debugfs_off_cache));
        ret = base;
 
-       /* Find the relevant block */
+       /* Find the relevant block:offset */
        list_for_each_entry(c, &map->debugfs_off_cache, list) {
                if (from >= c->min && from <= c->max) {
-                       *pos = c->min;
-                       return c->base_reg;
+                       fpos_offset = from - c->min;
+                       reg_offset = fpos_offset / map->debugfs_tot_len;
+                       *pos = c->min + (reg_offset * map->debugfs_tot_len);
+                       return c->base_reg + reg_offset;
                }
 
-               *pos = c->min;
-               ret = c->base_reg;
+               *pos = c->max;
+               ret = c->max_reg;
        }
 
        return ret;