From 6e64b6ccc1e46932768e3bb8974fc2e5589bca7a Mon Sep 17 00:00:00 2001 From: Pankaj Dubey Date: Thu, 18 Sep 2014 15:12:20 +0530 Subject: [PATCH] regmap: fix NULL pointer dereference in regmap_get_val_endian Recents commits for getting reg endianness causing NULL pointer dereference if dev is passed NULL in regmap_init_mmio. This patch fixes this issue, and allows to parse reg endianness only if dev and dev->of_node exist. Signed-off-by: Pankaj Dubey Signed-off-by: Mark Brown --- drivers/base/regmap/regmap.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 01ae4b829360..fd7ae9a10c4d 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -477,7 +477,7 @@ static enum regmap_endian regmap_get_val_endian(struct device *dev, const struct regmap_bus *bus, const struct regmap_config *config) { - struct device_node *np = dev->of_node; + struct device_node *np; enum regmap_endian endian; /* Retrieve the endianness specification from the regmap config */ @@ -487,15 +487,20 @@ static enum regmap_endian regmap_get_val_endian(struct device *dev, if (endian != REGMAP_ENDIAN_DEFAULT) return endian; - /* Parse the device's DT node for an endianness specification */ - if (of_property_read_bool(np, "big-endian")) - endian = REGMAP_ENDIAN_BIG; - else if (of_property_read_bool(np, "little-endian")) - endian = REGMAP_ENDIAN_LITTLE; + /* If the dev and dev->of_node exist try to get endianness from DT */ + if (dev && dev->of_node) { + np = dev->of_node; - /* If the endianness was specified in DT, use that */ - if (endian != REGMAP_ENDIAN_DEFAULT) - return endian; + /* Parse the device's DT node for an endianness specification */ + if (of_property_read_bool(np, "big-endian")) + endian = REGMAP_ENDIAN_BIG; + else if (of_property_read_bool(np, "little-endian")) + endian = REGMAP_ENDIAN_LITTLE; + + /* If the endianness was specified in DT, use that */ + if (endian != REGMAP_ENDIAN_DEFAULT) + return endian; + } /* Retrieve the endianness specification from the bus config */ if (bus && bus->val_format_endian_default)