[PATCH v2] staging: fbtft: differentiate between buffer and data types to fix sparse warning

[Alfonso Lima Astor]

sparse was complaning about an incorrect type cast:
drivers/staging/fbtft/fbtft-bus.c:60:1: warning: incorrect type in assignment 
(different base types)
drivers/staging/fbtft/fbtft-bus.c:60:1:expected unsigned short [unsigned] 
[short] [usertype] 
drivers/staging/fbtft/fbtft-bus.c:60:1:got restricted __be16 [usertype] 

drivers/staging/fbtft/fbtft-bus.c:60:1: warning: incorrect type in assignment 
(different base types)
drivers/staging/fbtft/fbtft-bus.c:60:1:expected unsigned short [unsigned] 
[short] [usertype] 
drivers/staging/fbtft/fbtft-bus.c:60:1:got restricted __be16 [usertype] 


The solution is to add an extra parameter to the macro to
differentiate between buffer type and data type.

Cc: Thomas Petazzoni 
Signed-off-by: Alfonso Lima Astor 

---
changes for v2:
Add maintainer to CC and add result of macro below '---'
to ease review of changes.

For "fbtft_write_reg8_bus8" and "fbtft_write_reg16_bus16 result"
is the same before and after patch. For "fbtft_write_reg16_bus8"
macro result after patch is:

void fbtft_write_reg16_bus8(struct fbtft_par *par, int len, ...)
{
va_list args;
int i, ret;
int offset = 0;
__be16 *buf = (__be16 *)par->buf;

if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) {
va_start(args, len);
for (i = 0; i < len; i++) {
buf[i] = cpu_to_be16((u16)va_arg(args, unsigned int));
}
va_end(args);
fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, 
__be16, buf, len, "%s: ", __func__);
}

va_start(args, len);

if (par->startbyte) {
*(u8 *)par->buf = par->startbyte;
buf = (__be16 *)(par->buf + 1);
offset = 1;
}

*buf = cpu_to_be16((u16)va_arg(args, unsigned int));
ret = fbtft_write_buf_dc(par, par->buf, sizeof(u16) + offset, 0);
if (ret < 0)
goto out;
len--;

if (par->startbyte)
*(u8 *)par->buf = par->startbyte | 0x2;

if (len) {
i = len;
while (i--)
*buf++ = cpu_to_be16((u16)va_arg(args, unsigned int));
fbtft_write_buf_dc(par, par->buf,
   len * (sizeof(u16) + offset), 1);
}
out:
va_end(args);
}

 drivers/staging/fbtft/fbtft-bus.c | 24 
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/staging/fbtft/fbtft-bus.c 
b/drivers/staging/fbtft/fbtft-bus.c
index a80b5d1..81e8af7 100644
--- a/drivers/staging/fbtft/fbtft-bus.c
+++ b/drivers/staging/fbtft/fbtft-bus.c
@@ -10,33 +10,33 @@
  *
  */
 
-#define define_fbtft_write_reg(func, type, modifier)  \
+#define define_fbtft_write_reg(func, buffer_type, data_type, modifier)\
 void func(struct fbtft_par *par, int len, ...)\
 { \
va_list args; \
int i, ret;   \
int offset = 0;   \
-   type *buf = (type *)par->buf; \
+   buffer_type *buf = (buffer_type *)par->buf;   \
  \
if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) {\
va_start(args, len);  \
for (i = 0; i < len; i++) {   \
-   buf[i] = (type)va_arg(args, unsigned int);\
+   buf[i] = modifier((data_type)va_arg(args, unsigned 
int)); \
} \
va_end(args); \
-   fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, 
type, buf, len, "%s: ", __func__);   \
+   fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, 
buffer_type, buf, len, "%s: ", __func__); \
} \
  \
va_start(args, len);  \
  \
if (par->startbyte) { \
*(u8 *)par->buf = par->startbyte; \
- 

[PATCH v2] staging: fbtft: differentiate between buffer and data types to fix sparse warning

[Alfonso Lima Astor]

sparse was complaning about an incorrect type cast:
drivers/staging/fbtft/fbtft-bus.c:60:1: warning: incorrect type in assignment 
(different base types)
drivers/staging/fbtft/fbtft-bus.c:60:1:expected unsigned short [unsigned] 
[short] [usertype] 
drivers/staging/fbtft/fbtft-bus.c:60:1:got restricted __be16 [usertype] 

drivers/staging/fbtft/fbtft-bus.c:60:1: warning: incorrect type in assignment 
(different base types)
drivers/staging/fbtft/fbtft-bus.c:60:1:expected unsigned short [unsigned] 
[short] [usertype] 
drivers/staging/fbtft/fbtft-bus.c:60:1:got restricted __be16 [usertype] 


The solution is to add an extra parameter to the macro to
differentiate between buffer type and data type.

Cc: Thomas Petazzoni 
Signed-off-by: Alfonso Lima Astor 

---
changes for v2:
Add maintainer to CC and add result of macro below '---'
to ease review of changes.

For "fbtft_write_reg8_bus8" and "fbtft_write_reg16_bus16 result"
is the same before and after patch. For "fbtft_write_reg16_bus8"
macro result after patch is:

void fbtft_write_reg16_bus8(struct fbtft_par *par, int len, ...)
{
va_list args;
int i, ret;
int offset = 0;
__be16 *buf = (__be16 *)par->buf;

if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) {
va_start(args, len);
for (i = 0; i < len; i++) {
buf[i] = cpu_to_be16((u16)va_arg(args, unsigned int));
}
va_end(args);
fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, 
__be16, buf, len, "%s: ", __func__);
}

va_start(args, len);

if (par->startbyte) {
*(u8 *)par->buf = par->startbyte;
buf = (__be16 *)(par->buf + 1);
offset = 1;
}

*buf = cpu_to_be16((u16)va_arg(args, unsigned int));
ret = fbtft_write_buf_dc(par, par->buf, sizeof(u16) + offset, 0);
if (ret < 0)
goto out;
len--;

if (par->startbyte)
*(u8 *)par->buf = par->startbyte | 0x2;

if (len) {
i = len;
while (i--)
*buf++ = cpu_to_be16((u16)va_arg(args, unsigned int));
fbtft_write_buf_dc(par, par->buf,
   len * (sizeof(u16) + offset), 1);
}
out:
va_end(args);
}

 drivers/staging/fbtft/fbtft-bus.c | 24 
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/staging/fbtft/fbtft-bus.c 
b/drivers/staging/fbtft/fbtft-bus.c
index a80b5d1..81e8af7 100644
--- a/drivers/staging/fbtft/fbtft-bus.c
+++ b/drivers/staging/fbtft/fbtft-bus.c
@@ -10,33 +10,33 @@
  *
  */
 
-#define define_fbtft_write_reg(func, type, modifier)  \
+#define define_fbtft_write_reg(func, buffer_type, data_type, modifier)\
 void func(struct fbtft_par *par, int len, ...)\
 { \
va_list args; \
int i, ret;   \
int offset = 0;   \
-   type *buf = (type *)par->buf; \
+   buffer_type *buf = (buffer_type *)par->buf;   \
  \
if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) {\
va_start(args, len);  \
for (i = 0; i < len; i++) {   \
-   buf[i] = (type)va_arg(args, unsigned int);\
+   buf[i] = modifier((data_type)va_arg(args, unsigned 
int)); \
} \
va_end(args); \
-   fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, 
type, buf, len, "%s: ", __func__);   \
+   fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, 
buffer_type, buf, len, "%s: ", __func__); \
} \
  \
va_start(args, len);  \
  \
if (par->startbyte) { \
*(u8 *)par->buf = par->startbyte; \
-