[PATCH V6] staging: goldfish: Fix pointer cast for 32 bits

[Peter Senna Tschudin <peter.senna@gmail.com>]

As the first argument of gf_write64() was of type unsigned long, and as
some calls to gf_write64() were casting the first argument from void *
to u64 the compiler and/or sparse were printing warnings for casts of
wrong sizes when compiling for i386.

This patch changes the type of the first argument of gf_write64() to
const void *, and update calls to the function. This change fixed the
warnings and allowed to remove casts from 3 calls to gf_write64().

In addition gf_write64() was renamed to gf_write_ptr() as the name was
misleading because it only writes 32 bits on 32 bit systems.

gf_write_dma_addr() was added to handle dma_addr_t values which is
used at drivers/staging/goldfish/goldfish_audio.c.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
---
When submiting V5, I havent tested the patch properly. It was
my fault. Tested by compilation only for i386 and for x86_64.

Changes from v5:
 - Added const to first argument of both gf_write_ptr()
   and gf_write_dma_addr()

Changes from V4:
 - Added the function gf_write_dma_addr()
 - Changed the subject line

Changes from V3:
 - Changed type of first argument of gf_write64
 - Renamed from gf_write64 to gf_write_ptr
 - Updated all calls to gf_write_ptr

Changes from V2:
 - Fixed spelling of complains
 - Updated commit message

Changes from V1:
 - Updated commit message

 drivers/platform/goldfish/goldfish_pipe.c | 18 +++++++++---------
 drivers/staging/goldfish/goldfish_audio.c |  2 +-
 drivers/staging/goldfish/goldfish_nand.c  |  2 +-
 drivers/tty/goldfish.c                    |  4 ++--
 include/linux/goldfish.h                  | 19 +++++++++++++++----
 5 files changed, 28 insertions(+), 17 deletions(-)

diff --git a/drivers/platform/goldfish/goldfish_pipe.c b/drivers/platform/goldfish/goldfish_pipe.c
index d9a09d9..aad16bc 100644
--- a/drivers/platform/goldfish/goldfish_pipe.c
+++ b/drivers/platform/goldfish/goldfish_pipe.c
@@ -158,8 +158,8 @@ static u32 goldfish_cmd_status(struct goldfish_pipe *pipe, u32 cmd)
 	struct goldfish_pipe_dev *dev = pipe->dev;
 
 	spin_lock_irqsave(&dev->lock, flags);
-	gf_write64((u64)(unsigned long)pipe, dev->base + PIPE_REG_CHANNEL,
-				dev->base + PIPE_REG_CHANNEL_HIGH);
+	gf_write_ptr(pipe, dev->base + PIPE_REG_CHANNEL,
+		     dev->base + PIPE_REG_CHANNEL_HIGH);
 	writel(cmd, dev->base + PIPE_REG_COMMAND);
 	status = readl(dev->base + PIPE_REG_STATUS);
 	spin_unlock_irqrestore(&dev->lock, flags);
@@ -172,8 +172,8 @@ static void goldfish_cmd(struct goldfish_pipe *pipe, u32 cmd)
 	struct goldfish_pipe_dev *dev = pipe->dev;
 
 	spin_lock_irqsave(&dev->lock, flags);
-	gf_write64((u64)(unsigned long)pipe, dev->base + PIPE_REG_CHANNEL,
-				dev->base + PIPE_REG_CHANNEL_HIGH);
+	gf_write_ptr(pipe, dev->base + PIPE_REG_CHANNEL,
+		     dev->base + PIPE_REG_CHANNEL_HIGH);
 	writel(cmd, dev->base + PIPE_REG_COMMAND);
 	spin_unlock_irqrestore(&dev->lock, flags);
 }
@@ -327,12 +327,12 @@ static ssize_t goldfish_pipe_read_write(struct file *filp, char __user *buffer,
 		spin_lock_irqsave(&dev->lock, irq_flags);
 		if (access_with_param(dev, CMD_WRITE_BUFFER + cmd_offset,
 				address, avail, pipe, &status)) {
-			gf_write64((u64)(unsigned long)pipe,
-				   dev->base + PIPE_REG_CHANNEL,
-				   dev->base + PIPE_REG_CHANNEL_HIGH);
+			gf_write_ptr(pipe, dev->base + PIPE_REG_CHANNEL,
+				     dev->base + PIPE_REG_CHANNEL_HIGH);
 			writel(avail, dev->base + PIPE_REG_SIZE);
-			gf_write64(address, dev->base + PIPE_REG_ADDRESS,
-				dev->base + PIPE_REG_ADDRESS_HIGH);
+			gf_write_ptr((void *)address,
+				     dev->base + PIPE_REG_ADDRESS,
+				     dev->base + PIPE_REG_ADDRESS_HIGH);
 			writel(CMD_WRITE_BUFFER + cmd_offset,
 					dev->base + PIPE_REG_COMMAND);
 			status = readl(dev->base + PIPE_REG_STATUS);
diff --git a/drivers/staging/goldfish/goldfish_audio.c b/drivers/staging/goldfish/goldfish_audio.c
index 702ae04..b0927e4 100644
--- a/drivers/staging/goldfish/goldfish_audio.c
+++ b/drivers/staging/goldfish/goldfish_audio.c
@@ -63,7 +63,7 @@ struct goldfish_audio {
 #define AUDIO_READ(data, addr)		(readl(data->reg_base + addr))
 #define AUDIO_WRITE(data, addr, x)	(writel(x, data->reg_base + addr))
 #define AUDIO_WRITE64(data, addr, addr2, x)	\
-	(gf_write64((u64)(x), data->reg_base + addr, data->reg_base+addr2))
+	(gf_write_dma_addr((x), data->reg_base + addr, data->reg_base+addr2))
 
 /*
  *  temporary variable used between goldfish_audio_probe() and
diff --git a/drivers/staging/goldfish/goldfish_nand.c b/drivers/staging/goldfish/goldfish_nand.c
index 213877a..66ae48f 100644
--- a/drivers/staging/goldfish/goldfish_nand.c
+++ b/drivers/staging/goldfish/goldfish_nand.c
@@ -87,7 +87,7 @@ static u32 goldfish_nand_cmd(struct mtd_info *mtd, enum nand_cmd cmd,
 		writel((u32)(addr >> 32), base + NAND_ADDR_HIGH);
 		writel((u32)addr, base + NAND_ADDR_LOW);
 		writel(len, base + NAND_TRANSFER_SIZE);
-		gf_write64((u64)ptr, base + NAND_DATA, base + NAND_DATA_HIGH);
+		gf_write_ptr(ptr, base + NAND_DATA, base + NAND_DATA_HIGH);
 		writel(cmd, base + NAND_COMMAND);
 		rv = readl(base + NAND_RESULT);
 	}
diff --git a/drivers/tty/goldfish.c b/drivers/tty/goldfish.c
index 0655fec..0f82c0b 100644
--- a/drivers/tty/goldfish.c
+++ b/drivers/tty/goldfish.c
@@ -59,7 +59,7 @@ static void goldfish_tty_do_write(int line, const char *buf, unsigned count)
 	struct goldfish_tty *qtty = &goldfish_ttys[line];
 	void __iomem *base = qtty->base;
 	spin_lock_irqsave(&qtty->lock, irq_flags);
-	gf_write64((u64)buf, base + GOLDFISH_TTY_DATA_PTR,
+	gf_write_ptr(buf, base + GOLDFISH_TTY_DATA_PTR,
 				base + GOLDFISH_TTY_DATA_PTR_HIGH);
 	writel(count, base + GOLDFISH_TTY_DATA_LEN);
 	writel(GOLDFISH_TTY_CMD_WRITE_BUFFER, base + GOLDFISH_TTY_CMD);
@@ -81,7 +81,7 @@ static irqreturn_t goldfish_tty_interrupt(int irq, void *dev_id)
 
 	count = tty_prepare_flip_string(&qtty->port, &buf, count);
 	spin_lock_irqsave(&qtty->lock, irq_flags);
-	gf_write64((u64)buf, base + GOLDFISH_TTY_DATA_PTR,
+	gf_write_ptr(buf, base + GOLDFISH_TTY_DATA_PTR,
 				base + GOLDFISH_TTY_DATA_PTR_HIGH);
 	writel(count, base + GOLDFISH_TTY_DATA_LEN);
 	writel(GOLDFISH_TTY_CMD_READ_BUFFER, base + GOLDFISH_TTY_CMD);
diff --git a/include/linux/goldfish.h b/include/linux/goldfish.h
index 569236e..93e080b 100644
--- a/include/linux/goldfish.h
+++ b/include/linux/goldfish.h
@@ -3,13 +3,24 @@
 
 /* Helpers for Goldfish virtual platform */
 
-static inline void gf_write64(unsigned long data,
-		void __iomem *portl, void __iomem *porth)
+static inline void gf_write_ptr(const void *ptr, void __iomem *portl,
+				void __iomem *porth)
 {
-	writel((u32)data, portl);
+	writel((u32)(unsigned long)ptr, portl);
 #ifdef CONFIG_64BIT
-	writel(data>>32, porth);
+	writel((unsigned long)ptr >> 32, porth);
 #endif
 }
 
+static inline void gf_write_dma_addr(const dma_addr_t addr,
+				     void __iomem *portl,
+				     void __iomem *porth)
+{
+	writel((u32)addr, portl);
+#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
+	writel(addr >> 32, porth);
+#endif
+}
+
+
 #endif /* __LINUX_GOLDFISH_H */
-- 
2.1.0