staging: gs_fpgaboot: change char to u8

The bitstream storage variables were changed from char to u8 arrays to
prevent issues such as negative lengths. This change makes the code
compatible with the "data" field in "struct firmware" which is of type
u8.
Signed-off-by: Jacob von Chorus <jacobvonchorus@cwphoto.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/gs_fpgaboot/gs_fpgaboot.c

@@ -42,16 +42,16 @@ static char	*file = "xlinx_fpga_firmware.bit";
 module_param(file, charp, 0444);
 MODULE_PARM_DESC(file, "Xilinx FPGA firmware file.");
 
-static void read_bitstream(char *bitdata, char *buf, int *offset, int rdsize)
+static void read_bitstream(u8 *bitdata, u8 *buf, int *offset, int rdsize)
 {
 	memcpy(buf, bitdata + *offset, rdsize);
 	*offset += rdsize;
 }
 
-static int readinfo_bitstream(char *bitdata, char *buf, int size, int *offset)
+static int readinfo_bitstream(u8 *bitdata, u8 *buf, int size, int *offset)
 {
-	char tbuf[64];
-	s32 len;
+	u8 tbuf[2];
+	u16 len;
 
 	/* read section char */
 	read_bitstream(bitdata, tbuf, offset, 1);
@@ -74,9 +74,9 @@ static int readinfo_bitstream(char *bitdata, char *buf, int size, int *offset)
 /*
  * read bitdata length
  */
-static int readlength_bitstream(char *bitdata, int *lendata, int *offset)
+static int readlength_bitstream(u8 *bitdata, int *lendata, int *offset)
 {
-	char tbuf[64];
+	u8 tbuf[4];
 
 	/* read section char */
 	read_bitstream(bitdata, tbuf, offset, 1);
@@ -98,9 +98,9 @@ static int readlength_bitstream(char *bitdata, int *lendata, int *offset)
 /*
  * read first 13 bytes to check bitstream magic number
  */
-static int readmagic_bitstream(char *bitdata, int *offset)
+static int readmagic_bitstream(u8 *bitdata, int *offset)
 {
-	char buf[13];
+	u8 buf[13];
 	int r;
 
 	read_bitstream(bitdata, buf, offset, 13);
@@ -135,12 +135,12 @@ static void gs_print_header(struct fpgaimage *fimage)
 
 static int gs_read_bitstream(struct fpgaimage *fimage)
 {
-	char *bitdata;
+	u8 *bitdata;
 	int offset;
 	int err;
 
 	offset = 0;
-	bitdata = (char *)fimage->fw_entry->data;
+	bitdata = (u8 *)fimage->fw_entry->data;
 
 	err = readmagic_bitstream(bitdata, &offset);
 	if (err)
@@ -209,11 +209,11 @@ static int gs_load_image(struct fpgaimage *fimage, char *fw_file)
 
 static int gs_download_image(struct fpgaimage *fimage, enum wbus bus_bytes)
 {
-	char *bitdata;
+	u8 *bitdata;
 	int size, i, cnt;
 
 	cnt = 0;
-	bitdata = (char *)fimage->fpgadata;
+	bitdata = (u8 *)fimage->fpgadata;
 	size = fimage->lendata;
 
 #ifdef DEBUG_FPGA

drivers/staging/gs_fpgaboot/gs_fpgaboot.h

@@ -47,5 +47,5 @@ struct fpgaimage {
 	char	date[MAX_STR];
 	char	time[MAX_STR];
 	int	lendata;
-	char	*fpgadata;
+	u8	*fpgadata;
 };