diff options
| author | Eugen Hristev <eugen.hristev@microchip.com> | 2020-12-04 18:06:55 +0200 |
|---|---|---|
| committer | Heiko Schocher <hs@denx.de> | 2021-02-21 06:05:08 +0100 |
| commit | 73c16692bcf7505d01596f48d2006dadfa3d14ab (patch) | |
| tree | a83532fccdae9b6f9b7d7da1a32afb6f5f78a832 /drivers/i2c/at91_i2c.c | |
| parent | 6befb51f349459c96ed64412070feda7472cf152 (diff) | |
i2c: at91: fix crash when using 'i2c probe'
When issuing 'i2c probe', the driver was crashing, because at probe
there is a request with zero length buffer to write to i2c bus.
The xfer_msg function assumes the buffer is always there, and never
checks for the buffer length.
=> i2c dev 0
Setting bus to 0
=> i2c probe
Valid chip addresses:
data abort
pc : [<7ffa97dc>] lr : [<7ffa96f8>]
reloc pc : [<66f277dc>] lr : [<66f276f8>]
sp : 7fb7c110 ip : 7ff87a28 fp : 7ff99938
r10: 00000002 r9 : 7fb7dec0 r8 : 00000000
r7 : e181c600 r6 : 7fb88c20 r5 : 00000000 r4 : 7fb7c128
r3 : 00000000 r2 : 00000001 r1 : 00000000 r0 : 00000009
Flags: nZCv IRQs off FIQs off Mode SVC_32
Code: eb0092f4 e1a00005 e8bd81f0 e594300c (e5d33000)
Resetting CPU ...
Fixes: 8800e0fa20 ("i2c: atmel: add i2c driver")
Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com>
Diffstat (limited to 'drivers/i2c/at91_i2c.c')
| -rw-r--r-- | drivers/i2c/at91_i2c.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/i2c/at91_i2c.c b/drivers/i2c/at91_i2c.c index aca8de9436..6b4c0e4804 100644 --- a/drivers/i2c/at91_i2c.c +++ b/drivers/i2c/at91_i2c.c @@ -51,6 +51,10 @@ static int at91_i2c_xfer_msg(struct at91_i2c_bus *bus, struct i2c_msg *msg) u32 i; int ret = 0; + /* if there is no message to send/receive, just exit quietly */ + if (msg->len == 0) + return ret; + readl(®->sr); if (is_read) { writel(TWI_CR_START, ®->cr); |