[ 10/22] drm/radeon: fix endian bugs in hw i2c atom routines

Greg Kroah-Hartman
2013-09-29T19:27:44Z

From: Alex Deucher <alexander.deucher@amd.com>

commit 4543eda52113d1e2cc0e9bf416f79597e6ef1ec7 upstream.

Need to swap the data fetched over i2c properly. This
is the same fix as the endian fix for aux channel
transactions.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/radeon/atombios_dp.c | 6 +++---
drivers/gpu/drm/radeon/atombios_i2c.c | 4 +++-
2 files changed, 6 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/radeon/atombios_dp.c
+++ b/drivers/gpu/drm/radeon/atombios_dp.c
@@ -51,7 +51,7 @@ static char *pre_emph_names[] = {
* or from atom. Note that atom operates on
* dw units.
*/
-static void radeon_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le)
+void radeon_atom_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le)
{
#ifdef __BIG_ENDIAN
u8 src_tmp[20], dst_tmp[20]; /* used for byteswapping */
@@ -101,7 +101,7 @@ static int radeon_process_aux_ch(struct

base = (unsigned char *)(rdev->mode_info.atom_context->scratch + 1);

- radeon_copy_swap(base, send, send_bytes, true);
+ radeon_atom_copy_swap(base, send, send_bytes, true);

args.v1.lpAuxRequest = cpu_to_le16((u16)(0 + 4));
args.v1.lpDataOut = cpu_to_le16((u16)(16 + 4));
@@ -138,7 +138,7 @@ static int radeon_process_aux_ch(struct
recv_bytes = recv_size;

if (recv && recv_size)
- radeon_copy_swap(recv, base + 16, recv_bytes, false);
+ radeon_atom_copy_swap(recv, base + 16, recv_bytes, false);

return recv_bytes;
}
--- a/drivers/gpu/drm/radeon/atombios_i2c.c
+++ b/drivers/gpu/drm/radeon/atombios_i2c.c
@@ -27,6 +27,8 @@
#include "radeon.h"
#include "atom.h"

+extern void radeon_atom_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le);
+
#define TARGET_HW_I2C_CLOCK 50

/* these are a limitation of ProcessI2cChannelTransaction not the hw */
@@ -77,7 +79,7 @@ static int radeon_process_i2c_ch(struct
}

if (!(flags & HW_I2C_WRITE))
- memcpy(buf, base, num);
+ radeon_atom_copy_swap(buf, base, num, false);

return 0;
}