From 815806e39bf6f7e7b34875d4a9609dbe76661782 Mon Sep 17 00:00:00 2001
From: Elaine Zhang <zhangqing@rock-chips.com>
Date: Thu, 18 Aug 2016 17:01:55 +0800
Subject: [PATCH] regmap: drop cache if the bus transfer error
regmap_write
->_regmap_raw_write
-->regcache_write first and than use map->bus->write to wirte i2c or spi
But if the i2c or spi transfer failed, But the cache is updated, So if I use
regmap_read will get the cache data which is not the real register value.
Signed-off-by: Elaine Zhang <zhangqing@rock-chips.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
drivers/base/regmap/regmap.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c
index 51fa7d66a393b..25d26bb189706 100644
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -1474,6 +1474,8 @@ int _regmap_raw_write(struct regmap *map, unsigned int reg,
ret = map->bus->write(map->bus_context, buf, len);
kfree(buf);
+ } else if (ret != 0 && !map->cache_bypass && map->format.parse_val) {
+ regcache_drop_region(map, reg, reg + 1);
}
trace_regmap_hw_write_done(map, reg, val_len / map->format.val_bytes);
--
2.30.2