diff --git a/linux_spi.c b/linux_spi.c
index de82def..44a2fcd 100644
--- a/linux_spi.c
+++ b/linux_spi.c
@@ -36,10 +36,10 @@
 static int linux_spi_shutdown(void *data);
 static int linux_spi_send_command(unsigned int writecnt, unsigned int readcnt,
 			const unsigned char *txbuf, unsigned char *rxbuf);
-static int linux_spi_read(struct flashchip *flash, uint8_t *buf, int start,
-			  int len);
+static int linux_spi_read(struct flashchip *flash, uint8_t *buf,
+			  unsigned int start, unsigned int len);
 static int linux_spi_write_256(struct flashchip *flash, uint8_t *buf,
-			       int start, int len);
+			       unsigned int start, unsigned int len);
 
 static const struct spi_programmer spi_programmer_linux = {
 	.type		= SPI_CONTROLLER_LINUX,
@@ -131,14 +131,14 @@
 	return 0;
 }
 
-static int linux_spi_read(struct flashchip *flash, uint8_t *buf, int start,
-			  int len)
+static int linux_spi_read(struct flashchip *flash, uint8_t *buf,
+			  unsigned int start, unsigned int len)
 {
-	return spi_read_chunked(flash, buf, start, len, getpagesize());
+	return spi_read_chunked(flash, buf, start, len, (unsigned)getpagesize());
 }
 
 static int linux_spi_write_256(struct flashchip *flash, uint8_t *buf,
-			       int start, int len)
+			       unsigned int start, unsigned int len)
 {
-	return spi_write_chunked(flash, buf, start, len, getpagesize() - 4);
+	return spi_write_chunked(flash, buf, start, len, ((unsigned)getpagesize()) - 4);
 }