From 8a2ceac6617a67d8a1ee4bd255743d577bde311a Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Thu, 4 Oct 2012 18:20:18 +0100 Subject: [PATCH] regmap: Split raw writes that cross window boundaries If a block write covers a paged memory region and crosses a window boundary then rather than failing the write split the transfer up into multiple writes, making the whole process more transparent for drivers. Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index baf9586b4fd8..96253cd949e9 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -852,8 +852,30 @@ static int _regmap_raw_write(struct regmap *map, unsigned int reg, range = _regmap_range_lookup(map, reg); if (range) { - ret = _regmap_select_page(map, ®, range, - val_len / map->format.val_bytes); + int val_num = val_len / map->format.val_bytes; + int win_offset = (reg - range->range_min) % range->window_len; + int win_residue = range->window_len - win_offset; + + /* If the write goes beyond the end of the window split it */ + while (val_num > win_residue) { + dev_dbg(map->dev, "Writing window %d/%d\n", + win_residue, val_len / map->format.val_bytes); + ret = _regmap_raw_write(map, reg, val, win_residue * + map->format.val_bytes); + if (ret != 0) + return ret; + + reg += win_residue; + val_num -= win_residue; + val += win_residue * map->format.val_bytes; + val_len -= win_residue * map->format.val_bytes; + + win_offset = (reg - range->range_min) % + range->window_len; + win_residue = range->window_len - win_offset; + } + + ret = _regmap_select_page(map, ®, range, val_num); if (ret != 0) return ret; } -- 2.20.1