regmap: mmio: Fix the bug of 'offset' value parsing.
'offset = *(u32 *)reg;'
This will be okey for 32/64-bits register device, but for 8/16-bits
register ones, the 'offset' value will overflow, for example:
The IMX2 Watchdog, whose registers and values are all 16-bits:
If the IO base virtual address is ctx->regs = 0x888c0000, and the now
doing the 0x00 register accessing:
Using 'offset = *(u32 *)reg' the offset value will possiblly be 0x77310000,
Using 'offset = *(u16 *)reg' the offset value will be 0x0000.
In the regmap_mmio_gather_write(), ctx->regs + 0x7731000 will be 0xffbd0000,
but actually it should be ctx->regs + 0x0000 = 0x888c0000.
Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
diff --git a/drivers/base/regmap/regmap-mmio.c b/drivers/base/regmap/regmap-mmio.c
index 1e03e7f..dff32c6 100644
--- a/drivers/base/regmap/regmap-mmio.c
+++ b/drivers/base/regmap/regmap-mmio.c
@@ -66,12 +66,31 @@
BUG_ON(count % 2 != 0);
}
+static inline unsigned int
+regmap_mmio_get_offset(const void *reg, size_t reg_size)
+{
+ switch (reg_size) {
+ case 1:
+ return *(u8 *)reg;
+ case 2:
+ return *(u16 *)reg;
+ case 4:
+ return *(u32 *)reg;
+#ifdef CONFIG_64BIT
+ case 8:
+ return *(u64 *)reg;
+#endif
+ default:
+ BUG();
+ }
+}
+
static int regmap_mmio_gather_write(void *context,
const void *reg, size_t reg_size,
const void *val, size_t val_size)
{
struct regmap_mmio_context *ctx = context;
- u32 offset;
+ unsigned int offset;
int ret;
regmap_mmio_regsize_check(reg_size);
@@ -82,7 +101,7 @@
return ret;
}
- offset = *(u32 *)reg;
+ offset = regmap_mmio_get_offset(reg, reg_size);
while (val_size) {
switch (ctx->val_bytes) {
@@ -118,7 +137,7 @@
static int regmap_mmio_write(void *context, const void *data, size_t count)
{
struct regmap_mmio_context *ctx = context;
- u32 offset = ctx->reg_bytes + ctx->pad_bytes;
+ unsigned int offset = ctx->reg_bytes + ctx->pad_bytes;
regmap_mmio_count_check(count);
@@ -131,7 +150,7 @@
void *val, size_t val_size)
{
struct regmap_mmio_context *ctx = context;
- u32 offset;
+ unsigned int offset;
int ret;
regmap_mmio_regsize_check(reg_size);
@@ -142,7 +161,7 @@
return ret;
}
- offset = *(u32 *)reg;
+ offset = regmap_mmio_get_offset(reg, reg_size);
while (val_size) {
switch (ctx->val_bytes) {