[PATCH v1] drm/ast: Fixed the casting issue reported by sparse

[KuoHsiang Chou]

V1:
1.Fixed sparse:cast truncates bits form constant value ()cast
  truncates bits from constant value (ffffffffffffff00 becomes 0)

Reported-by: kernel test robot <l...@intel.com>
Signed-off-by: KuoHsiang Chou <kuohsiang_c...@aspeedtech.com>
---
 drivers/gpu/drm/ast/ast_dp.c  | 8 ++++----
 drivers/gpu/drm/ast/ast_drv.h | 2 +-
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_dp.c b/drivers/gpu/drm/ast/ast_dp.c
index f573d5824..2c71b8eef 100644
--- a/drivers/gpu/drm/ast/ast_dp.c
+++ b/drivers/gpu/drm/ast/ast_dp.c
@@ -34,7 +34,7 @@ int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata)
                 * CRE4[7:0]: Read-Pointer for EDID (Unit: 4bytes); valid 
range: 0~64
                 */
                ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xE4,
-                                       (u8) ~ASTDP_EDID_READ_POINTER_MASK, 
(u8) i);
+                                       ASTDP_AND_CLEAR_MASK, (u8) i);
                j = 0;

                /*
@@ -274,8 +274,8 @@ void ast_dp_set_mode(struct drm_crtc *crtc, struct 
ast_vbios_mode_info *vbios_mo
         * CRE1[7:0]: MISC1 (default: 0x00)
         * CRE2[7:0]: video format index (0x00 ~ 0x20 or 0x40 ~ 0x50)
         */
-       ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xE0, (u8) 
~ASTDP_CLEAR_MASK,
+       ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xE0, 
ASTDP_AND_CLEAR_MASK,
                                ASTDP_MISC0_24bpp);
-       ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xE1, (u8) 
~ASTDP_CLEAR_MASK, ASTDP_MISC1);
-       ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xE2, (u8) 
~ASTDP_CLEAR_MASK, ModeIdx);
+       ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xE1, 
ASTDP_AND_CLEAR_MASK, ASTDP_MISC1);
+       ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xE2, 
ASTDP_AND_CLEAR_MASK, ModeIdx);
 }
diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index a34db4380..2e44b971c 100644
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -433,7 +433,7 @@ int ast_mode_config_init(struct ast_private *ast);
  */
 #define ASTDP_MISC0_24bpp                      BIT(5)
 #define ASTDP_MISC1                            0
-#define ASTDP_CLEAR_MASK                       GENMASK(7, 0)
+#define ASTDP_AND_CLEAR_MASK           0x00

 /*
  * ASTDP resoultion table:

base-commit: ab3bfa333f25d26bb8bf414419f9a2e6a46a141f
--
2.27.0