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From: Niklas Schnelle <schnelle@linux.ibm.com>
To: Helge Deller <deller@gmx.de>
Cc: linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
        Arnd Bergmann <arnd@kernel.org>, Heiko Carstens <hca@linux.ibm.com>,
        linux-kernel@vger.kernel.org, Niklas Schnelle <schnelle@linux.ibm.com>
Subject: [PATCH v2 1/1] video: Handle HAS_IOPORT dependencies
Date: Tue, 14 May 2024 15:08:58 +0200
Message-Id: <20240514130858.3048650-2-schnelle@linux.ibm.com>
In-Reply-To: <20240514130858.3048650-1-schnelle@linux.ibm.com>
References: <20240514130858.3048650-1-schnelle@linux.ibm.com>
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In a future patch HAS_IOPORT=n will disable inb()/outb() and friends at
compile time. We thus need to #ifdef functions and their callsites which
unconditionally use these I/O accessors. In the include/video/vga.h
these are conveniently all those functions with the vga_io_* prefix.

Co-developed-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
---
Note: This patch does not depend any not-yet-mainline HAS_IOPORT changes
and may be merged via subsystem specific trees at your earliest
convenience.

v1 -> v2:
- Moved vga_mm_r(), vga_mm_w(), vga_mm_w_fast() above #ifdef CONFIG_HAS_IOPORT
  to use them in with or without I/O port variants.
- Duplicated vga_r(), vga_w(), vga_w_fast() functions as non-I/O port variants
  to get rid of in-code #ifdef (Arnd)
- Got rid of if (regbase) logic inversion needed for in-code #ifdef

 include/video/vga.h | 58 ++++++++++++++++++++++++++++++++-------------
 1 file changed, 42 insertions(+), 16 deletions(-)

diff --git a/include/video/vga.h b/include/video/vga.h
index 947c0abd04ef..468764d6727a 100644
--- a/include/video/vga.h
+++ b/include/video/vga.h
@@ -197,9 +197,26 @@ struct vgastate {
 extern int save_vga(struct vgastate *state);
 extern int restore_vga(struct vgastate *state);
 
+static inline unsigned char vga_mm_r (void __iomem *regbase, unsigned short port)
+{
+	return readb (regbase + port);
+}
+
+static inline void vga_mm_w (void __iomem *regbase, unsigned short port, unsigned char val)
+{
+	writeb (val, regbase + port);
+}
+
+static inline void vga_mm_w_fast (void __iomem *regbase, unsigned short port,
+				  unsigned char reg, unsigned char val)
+{
+	writew (VGA_OUT16VAL (val, reg), regbase + port);
+}
+
 /*
  * generic VGA port read/write
  */
+#ifdef CONFIG_HAS_IOPORT
 
 static inline unsigned char vga_io_r (unsigned short port)
 {
@@ -217,22 +234,6 @@ static inline void vga_io_w_fast (unsigned short port, unsigned char reg,
 	outw(VGA_OUT16VAL (val, reg), port);
 }
 
-static inline unsigned char vga_mm_r (void __iomem *regbase, unsigned short port)
-{
-	return readb (regbase + port);
-}
-
-static inline void vga_mm_w (void __iomem *regbase, unsigned short port, unsigned char val)
-{
-	writeb (val, regbase + port);
-}
-
-static inline void vga_mm_w_fast (void __iomem *regbase, unsigned short port,
-				  unsigned char reg, unsigned char val)
-{
-	writew (VGA_OUT16VAL (val, reg), regbase + port);
-}
-
 static inline unsigned char vga_r (void __iomem *regbase, unsigned short port)
 {
 	if (regbase)
@@ -258,7 +259,24 @@ static inline void vga_w_fast (void __iomem *regbase, unsigned short port,
 	else
 		vga_io_w_fast (port, reg, val);
 }
+#else /* CONFIG_HAS_IOPORT */
+static inline unsigned char vga_r (void __iomem *regbase, unsigned short port)
+{
+	return vga_mm_r (regbase, port);
+}
 
+static inline void vga_w (void __iomem *regbase, unsigned short port, unsigned char val)
+{
+	vga_mm_w (regbase, port, val);
+}
+
+
+static inline void vga_w_fast (void __iomem *regbase, unsigned short port,
+			       unsigned char reg, unsigned char val)
+{
+	vga_mm_w_fast (regbase, port, reg, val);
+}
+#endif /* CONFIG_HAS_IOPORT */
 
 /*
  * VGA CRTC register read/write
@@ -280,6 +298,7 @@ static inline void vga_wcrt (void __iomem *regbase, unsigned char reg, unsigned
 #endif /* VGA_OUTW_WRITE */
 }
 
+#ifdef CONFIG_HAS_IOPORT
 static inline unsigned char vga_io_rcrt (unsigned char reg)
 {
         vga_io_w (VGA_CRT_IC, reg);
@@ -295,6 +314,7 @@ static inline void vga_io_wcrt (unsigned char reg, unsigned char val)
         vga_io_w (VGA_CRT_DC, val);
 #endif /* VGA_OUTW_WRITE */
 }
+#endif /* CONFIG_HAS_IOPORT */
 
 static inline unsigned char vga_mm_rcrt (void __iomem *regbase, unsigned char reg)
 {
@@ -333,6 +353,7 @@ static inline void vga_wseq (void __iomem *regbase, unsigned char reg, unsigned
 #endif /* VGA_OUTW_WRITE */
 }
 
+#ifdef CONFIG_HAS_IOPORT
 static inline unsigned char vga_io_rseq (unsigned char reg)
 {
         vga_io_w (VGA_SEQ_I, reg);
@@ -348,6 +369,7 @@ static inline void vga_io_wseq (unsigned char reg, unsigned char val)
         vga_io_w (VGA_SEQ_D, val);
 #endif /* VGA_OUTW_WRITE */
 }
+#endif /* CONFIG_HAS_IOPORT */
 
 static inline unsigned char vga_mm_rseq (void __iomem *regbase, unsigned char reg)
 {
@@ -385,6 +407,7 @@ static inline void vga_wgfx (void __iomem *regbase, unsigned char reg, unsigned
 #endif /* VGA_OUTW_WRITE */
 }
 
+#ifdef CONFIG_HAS_IOPORT
 static inline unsigned char vga_io_rgfx (unsigned char reg)
 {
         vga_io_w (VGA_GFX_I, reg);
@@ -400,6 +423,7 @@ static inline void vga_io_wgfx (unsigned char reg, unsigned char val)
         vga_io_w (VGA_GFX_D, val);
 #endif /* VGA_OUTW_WRITE */
 }
+#endif /* CONFIG_HAS_IOPORT */
 
 static inline unsigned char vga_mm_rgfx (void __iomem *regbase, unsigned char reg)
 {
@@ -434,6 +458,7 @@ static inline void vga_wattr (void __iomem *regbase, unsigned char reg, unsigned
         vga_w (regbase, VGA_ATT_W, val);
 }
 
+#ifdef CONFIG_HAS_IOPORT
 static inline unsigned char vga_io_rattr (unsigned char reg)
 {
         vga_io_w (VGA_ATT_IW, reg);
@@ -445,6 +470,7 @@ static inline void vga_io_wattr (unsigned char reg, unsigned char val)
         vga_io_w (VGA_ATT_IW, reg);
         vga_io_w (VGA_ATT_W, val);
 }
+#endif /* CONFIG_HAS_IOPORT */
 
 static inline unsigned char vga_mm_rattr (void __iomem *regbase, unsigned char reg)
 {
-- 
2.40.1