media: firewire: Fix app_info parameter type in avc_ca{,_app}_info

[ Upstream commit b2e9a4eda11fd2cb1e6714e9ad3f455c402568ff ]

Clang warns:

drivers/media/firewire/firedtv-avc.c:999:45: warning: implicit
conversion from 'int' to 'char' changes value from 159 to -97
[-Wconstant-conversion]
        app_info[0] = (EN50221_TAG_APP_INFO >> 16) & 0xff;
                    ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
drivers/media/firewire/firedtv-avc.c:1000:45: warning: implicit
conversion from 'int' to 'char' changes value from 128 to -128
[-Wconstant-conversion]
        app_info[1] = (EN50221_TAG_APP_INFO >>  8) & 0xff;
                    ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
drivers/media/firewire/firedtv-avc.c:1040:44: warning: implicit
conversion from 'int' to 'char' changes value from 159 to -97
[-Wconstant-conversion]
        app_info[0] = (EN50221_TAG_CA_INFO >> 16) & 0xff;
                    ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
drivers/media/firewire/firedtv-avc.c:1041:44: warning: implicit
conversion from 'int' to 'char' changes value from 128 to -128
[-Wconstant-conversion]
        app_info[1] = (EN50221_TAG_CA_INFO >>  8) & 0xff;
                    ~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~
4 warnings generated.

Change app_info's type to unsigned char to match the type of the
member msg in struct ca_msg, which is the only thing passed into the
app_info parameter in this function.

Link: https://github.com/ClangBuiltLinux/linux/issues/105

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/media/firewire/firedtv-avc.c

@@ -968,7 +968,8 @@ static int get_ca_object_length(struct avc_response_frame *r)
 	return r->operand[7];
 }
 
-int avc_ca_app_info(struct firedtv *fdtv, char *app_info, unsigned int *len)
+int avc_ca_app_info(struct firedtv *fdtv, unsigned char *app_info,
+		    unsigned int *len)
 {
 	struct avc_command_frame *c = (void *)fdtv->avc_data;
 	struct avc_response_frame *r = (void *)fdtv->avc_data;
@@ -1009,7 +1010,8 @@ out:
 	return ret;
 }
 
-int avc_ca_info(struct firedtv *fdtv, char *app_info, unsigned int *len)
+int avc_ca_info(struct firedtv *fdtv, unsigned char *app_info,
+		unsigned int *len)
 {
 	struct avc_command_frame *c = (void *)fdtv->avc_data;
 	struct avc_response_frame *r = (void *)fdtv->avc_data;

drivers/media/firewire/firedtv.h

@@ -124,8 +124,10 @@ int avc_lnb_control(struct firedtv *fdtv, char voltage, char burst,
 		    struct dvb_diseqc_master_cmd *diseqcmd);
 void avc_remote_ctrl_work(struct work_struct *work);
 int avc_register_remote_control(struct firedtv *fdtv);
-int avc_ca_app_info(struct firedtv *fdtv, char *app_info, unsigned int *len);
-int avc_ca_info(struct firedtv *fdtv, char *app_info, unsigned int *len);
+int avc_ca_app_info(struct firedtv *fdtv, unsigned char *app_info,
+		    unsigned int *len);
+int avc_ca_info(struct firedtv *fdtv, unsigned char *app_info,
+		unsigned int *len);
 int avc_ca_reset(struct firedtv *fdtv);
 int avc_ca_pmt(struct firedtv *fdtv, char *app_info, int length);
 int avc_ca_get_time_date(struct firedtv *fdtv, int *interval);