leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

drm/radeon/atom: fix bus probes when hw_i2c is set (v2)

Browse Source 
When probing the bus, we need to set the byte count
to 0 rather than 1.

v2: Don't count the first byte.

bug:
https://bugzilla.kernel.org/show_bug.cgi?id=66241

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
This commit is contained in:
Alex Deucher 2013-12-03 17:16:49 -05:00
parent 53dc0b0c94
commit ffd3d3361d
1 changed files with 9 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
drivers/gpu/drm/radeon/atombios_i2c.c
View File

@ -44,7 +44,7 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args;
int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction);
unsigned char *base;
u16 out;
u16 out = cpu_to_le16(0);
memset(&args, 0, sizeof(args));
@ -55,11 +55,14 @@ static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 3)\n", num);
return -EINVAL;
}
args.ucRegIndex = buf[0];
if (num > 1) {
if (buf == NULL)
args.ucRegIndex = 0;
else
args.ucRegIndex = buf[0];
if (num)
num--;
if (num)
memcpy(&out, &buf[1], num);
}
args.lpI2CDataOut = cpu_to_le16(out);
} else {
if (num > ATOM_MAX_HW_I2C_READ) {
@ -96,14 +99,14 @@ int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
struct i2c_msg *p;
int i, remaining, current_count, buffer_offset, max_bytes, ret;
u8 buf = 0, flags;
u8 flags;
/* check for bus probe */
p = &msgs[0];
if ((num == 1) && (p->len == 0)) {
ret = radeon_process_i2c_ch(i2c,
p->addr, HW_I2C_WRITE,
&buf, 1);
NULL, 0);
if (ret)
return ret;
else