ARM: mostly harmless gcc warnings

Most patches from the first time this was posted have been adopted by a subsystem maintainer or were show to be obsolete. Here are the remaining ones again.

I'm planning to submit those patches that are still necessary by the time we have an -rc1 through the arm-soc tree, but my preference is still to have them go through the subsystem maintainers.

Olof: should we add it to for-next?

Arnd

Arnd Bergmann (8):
SCSI: ARM: ncr5380/oak uses no interrupts
SCSI: ARM: make fas216_dumpinfo function conditional mm/slob: use min_t() to compare ARCH_SLAB_MINALIGN
USB: EHCI: mark ehci_orion_conf_mbus_windows __devinit
clk: don't mark clkdev_add_table as init
pcmcia: sharpsl: don't discard sharpsl_pcmcia_ops
video: mark nuc900fb_map_video_memory as __devinit spi/s3c64xx: use correct dma_transfer_direction type

 drivers/clk/clkdev.c            |    2 +-
 drivers/pcmcia/pxa2xx_sharpsl.c |    2 +-
 drivers/scsi/arm/fas216.c       |    2 +-
 drivers/scsi/arm/oak.c          |    1 +
 drivers/spi/spi-s3c64xx.c       |    2 +-
 drivers/usb/host/ehci-orion.c   |    2 +-
 drivers/video/nuc900fb.c        |    2 +-
 mm/slob.c                       |    6 +++---
 8 files changed, 10 insertions(+), 9 deletions(-)

1.7.10

Cc: "James E.J. Bottomley" <[email protected]>
Cc: Ben Dooks <[email protected]>
Cc: Dominik Brodowski <[email protected]>
Cc: Florian Tobias Schandinat <[email protected]>
Cc: Grant Likely <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Jochen Friedrich <[email protected]>
Cc: Kukjin Kim <[email protected]>
Cc: Mike Turquette <[email protected]>
Cc: Pavel Machek <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: Russell King <[email protected]>
Cc: Wan ZongShun <[email protected]>
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-fbdev at vger.kernel.org
Cc: linux-pcmcia at lists.infradead.org
Cc: linux-samsung-soc at vger.kernel.org
Cc: linux-scsi at vger.kernel.org
Cc: linux-usb at vger.kernel.org
Cc: spi-devel-general at lists.sourceforge.net
Cc: stable at vger.kernel.org

The ncr5380 driver is included by multiple board specific drivers, which may or may not use the interrupt handler. The oak variant doesn't, and should set the DONT_USE_INTR macro.

Without this patch, building rpc_defconfig results in:

drivers/scsi/arm/../NCR5380.c:1160:20: warning: 'oakscsi_intr' defined but not used [-Wunused-function]

---
 drivers/scsi/arm/oak.c |    1 +
 1 file changed, 1 insertion(+)

index d25f944..fc6a5aa 100644
@@ -21,6 +21,7 @@
 /*#define PSEUDO_DMA*/
 
 #define OAKSCSI_PUBLIC_RELEASE 1
+#define DONT_USE_INTR
 
 #define priv(host)			((struct NCR5380_hostdata *)(host)->hostdata)
 #define NCR5380_local_declare()		void __iomem *_base

1.7.10

The fas216_dumpinfo function is only used by __fas216_checkmagic, which is conditionally compiled, so we should put both functions inside of the same #ifdef.

Without this patch, building rpc_defconfig results in:

drivers/scsi/arm/fas216.c:182:13: warning: 'fas216_dumpinfo' defined but not used [-Wunused-function]

---
 drivers/scsi/arm/fas216.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 6206a66..737554c 100644
@@ -179,6 +179,7 @@ static void print_SCp(struct scsi_pointer *SCp, const char *prefix, const char *
 		SCp->buffers_residual, suffix);
 }
 
+#ifdef CHECK_STRUCTURE
 static void fas216_dumpinfo(FAS216_Info *info)
 {
 	static int used = 0;

@@ -223,7 +224,6 @@ static void fas216_dumpinfo(FAS216_Info *info)
 		info->internal_done, info->magic_end);
 }
 
-#ifdef CHECK_STRUCTURE
 static void __fas216_checkmagic(FAS216_Info *info, const char *func)
 {
 	int corruption = 0;

1.7.10

The definition of ARCH_SLAB_MINALIGN is architecture dependent and can be either of type size_t or int. Comparing that value with ARCH_KMALLOC_MINALIGN can cause harmless warnings on platforms where they are different. Since both are always small positive integer numbers, using the size_t type to compare them is safe and gets rid of the warning.

Without this patch, building ARM collie_defconfig results in:

mm/slob.c: In function '__kmalloc_node':
mm/slob.c:431:152: warning: comparison of distinct pointer types lacks a cast [enabled by default] mm/slob.c: In function 'kfree':
mm/slob.c:484:153: warning: comparison of distinct pointer types lacks a cast [enabled by default] mm/slob.c: In function 'ksize':
mm/slob.c:503:153: warning: comparison of distinct pointer types lacks a cast [enabled by default]

---
 mm/slob.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

index 45d4ca7..497c55e 100644
@@ -428,7 +428,7 @@ out:
 void *__kmalloc_node(size_t size, gfp_t gfp, int node)
 {
 	unsigned int *m;
-	int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+	int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
 	void *ret;
 
 	gfp &= gfp_allowed_mask;

@@ -481,7 +481,7 @@ void kfree(const void *block)
 
 	sp = virt_to_page(block);
 	if (PageSlab(sp)) {
-		int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+		int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
 		unsigned int *m = (unsigned int *)(block - align);
 		slob_free(m, *m + align);
 	} else

@@ -500,7 +500,7 @@ size_t ksize(const void *block)
 
 	sp = virt_to_page(block);
 	if (PageSlab(sp)) {
-		int align = max(ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
+		int align = max_t(size_t, ARCH_KMALLOC_MINALIGN, ARCH_SLAB_MINALIGN);
 		unsigned int *m = (unsigned int *)(block - align);
 		return SLOB_UNITS(*m) * SLOB_UNIT;
 	} else

1.7.10

The __devinit section is going away soon, but while it's still there, we get a correct warning about ehci_orion_conf_mbus_windows being discarded before its caller, so it should be marked __devinit rather than __init.

Without this patch, building dove_defconfig results in:

WARNING: drivers/usb/host/built-in.o(.devinit.text+0x8a4): Section mismatch in reference from the function ehci_orion_drv_probe() to the function .init.text:ehci_orion_conf_mbus_windows() The function __devinit ehci_orion_drv_probe() references
a function __init ehci_orion_conf_mbus_windows().
If ehci_orion_conf_mbus_windows is only used by ehci_orion_drv_probe then
annotate ehci_orion_conf_mbus_windows with a matching annotation.

---
 drivers/usb/host/ehci-orion.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 8892d36..1f5dd5e 100644
@@ -160,7 +160,7 @@ static const struct hc_driver ehci_orion_hc_driver = {
 	.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
 };
 
-static void __init
+static void __devinit
 ehci_orion_conf_mbus_windows(struct usb_hcd *hcd,
 			     const struct mbus_dram_target_info *dram)
 {

1.7.10

s3c2440_clk_add is a subsys_interface method and calls clkdev_add_table, which means we might be calling it after the __init section is discarded.

Without this patch, building mini2440_defconfig results in:

WARNING: vmlinux.o(.text+0x9848): Section mismatch in reference from the function s3c2440_clk_add() to the function .init.text:clkdev_add_table() The function s3c2440_clk_add() references
the function __init clkdev_add_table().
This is often because s3c2440_clk_add lacks a __init
annotation or the annotation of clkdev_add_table is wrong.

---
 drivers/clk/clkdev.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 442a313..6956857 100644
@@ -179,7 +179,7 @@ void clkdev_add(struct clk_lookup *cl)
 }
 EXPORT_SYMBOL(clkdev_add);
 
-void __init clkdev_add_table(struct clk_lookup *cl, size_t num)
+void clkdev_add_table(struct clk_lookup *cl, size_t num)
 {
 	mutex_lock(&clocks_mutex);
 	while (num--) {

1.7.10

I'm not sure this is the right thing to do. I suspect this comes from the stupidly complex samsung code, and that this is actually safe - I suspect that s3c2440_clk_add() needs to be appropriately marked, but then you end up having to trace its call path through various structures etc.

Yes, you are right. I have verified now that the only code path into s3c2440_clk_add() is from "int __init s3c2440_init(void)", so s3c2440_clk_add can be marked __init_refok.

I'll follow up with a new patch to replace this one.

Arnd

The sharpsl_pcmcia_ops structure gets passed into sa11xx_drv_pcmcia_probe, where it gets accessed at run-time, unlike all other pcmcia drivers that pass their structures into platform_device_add_data, which makes a copy.

This means the gcc warning is valid and the structure must not be marked as __initdata.

Without this patch, building collie_defconfig results in:

drivers/pcmcia/pxa2xx_sharpsl.c:22:31: fatal error: mach-pxa/hardware.h: No such file or directory compilation terminated.
make[3]: *** [drivers/pcmcia/pxa2xx_sharpsl.o] Error 1
make[2]: *** [drivers/pcmcia] Error 2
make[1]: *** [drivers] Error 2
make: *** [sub-make] Error 2

---
 drivers/pcmcia/pxa2xx_sharpsl.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index b066273..7dd879c 100644
@@ -194,7 +194,7 @@ static void sharpsl_pcmcia_socket_suspend(struct soc_pcmcia_socket *skt)
 	sharpsl_pcmcia_init_reset(skt);
 }
 
-static struct pcmcia_low_level sharpsl_pcmcia_ops __initdata = {
+static struct pcmcia_low_level sharpsl_pcmcia_ops = {
 	.owner                  = THIS_MODULE,
 	.hw_init                = sharpsl_pcmcia_hw_init,
 	.socket_state           = sharpsl_pcmcia_socket_state,

1.7.10

nuc900fb_map_video_memory is called by an devinit function that may be called at run-time, but the function itself is marked __init and will be discarded after boot.

To avoid calling into a function that may have been overwritten, mark nuc900fb_map_video_memory itself as __devinit.

Without this patch, building nuc950_defconfig results in:

WARNING: drivers/video/built-in.o(.devinit.text+0x26c): Section mismatch in reference from the function nuc900fb_probe() to the function .init.text:nuc900fb_map_video_memory() The function __devinit nuc900fb_probe() references
a function __init nuc900fb_map_video_memory().
If nuc900fb_map_video_memory is only used by nuc900fb_probe then
annotate nuc900fb_map_video_memory with a matching annotation.

---
 drivers/video/nuc900fb.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index e10f551..b31b12b 100644
@@ -387,7 +387,7 @@ static int nuc900fb_init_registers(struct fb_info *info)
  *    The buffer should be a non-cached, non-buffered, memory region
  *    to allow palette and pixel writes without flushing the cache.
  */
-static int __init nuc900fb_map_video_memory(struct fb_info *info)
+static int __devinit nuc900fb_map_video_memory(struct fb_info *info)
 {
 	struct nuc900fb_info *fbi = info->par;
 	dma_addr_t map_dma;

1.7.10

2012/10/10 Arnd Bergmann <[email protected]>:

Thanks for your patch.

Wan ZongShun.
www.mcuos.com

Applied.

Thanks,

Florian Tobias Schandinat

There is a subtle difference between dma_transfer_direction and
dma_data_direction: the former is used by the dmaengine framework, while the latter is used by the dma-mapping API. Although the purpose is comparable, the actual values are different and must not be mixed. In this case, the driver just wants to use dma_transfer_direction.

Without this patch, building s3c6400_defconfig results in:

drivers/spi/spi-s3c64xx.c: In function 's3c64xx_spi_dmacb':
drivers/spi/spi-s3c64xx.c:239:21: warning: comparison between
'enum dma_data_direction' and 'enum dma_transfer_direction' [-Wenum-compare]

---
 drivers/spi/spi-s3c64xx.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index d1c8441f..2e44dd6 100644
@@ -132,7 +132,7 @@
 
 struct s3c64xx_spi_dma_data {
 	unsigned		ch;
-	enum dma_data_direction direction;
+	enum dma_transfer_direction direction;
 	enum dma_ch	dmach;
 	struct property		*dma_prop;
 };

1.7.10

BTW, don't we need following accordingly?

index 1a81c90..a0bb55e 100644
@@ -1067,11 +1067,11 @@ static int __devinit s3c64xx_spi_get_dmares(
 
 	if (tx) {
 		dma_data = &sdd->tx_dma;
-		dma_data->direction = DMA_TO_DEVICE;
+		dma_data->direction = DMA_MEM_TO_DEV;
 		chan_str = "tx";
 	} else {
 		dma_data = &sdd->rx_dma;
-		dma_data->direction = DMA_FROM_DEVICE;
+		dma_data->direction = DMA_DEV_TO_MEM;
 		chan_str = "rx";
 	}
 

Thanks.

Best regards,
Kgene.
--
Kukjin Kim <[email protected]>, Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd.

From: Arnd Bergmann <[email protected]>
Date: Mon, 30 Apr 2012 16:31:27 +0000
Subject: [PATCH] spi/s3c64xx: use correct dma_transfer_direction type

There is a subtle difference between dma_transfer_direction and
dma_data_direction: the former is used by the dmaengine framework, while the latter is used by the dma-mapping API. Although the purpose is comparable, the actual values are different and must not be mixed. In this case, the driver just wants to use dma_transfer_direction.

Without this patch, building s3c6400_defconfig results in:

drivers/spi/spi-s3c64xx.c: In function 's3c64xx_spi_dmacb':
drivers/spi/spi-s3c64xx.c:239:21: warning: comparison between
'enum dma_data_direction' and 'enum dma_transfer_direction' [-Wenum-compare]

As pointed out by Kukjin Kim, this also changes the use of constants from DMA_FROM_DEVICE/DMA_TO_DEVICE to DMA_DEV_TO_MEM/DMA_MEM_TO_DEV.

index d1c8441f..cd43b4b 100644
@@ -132,7 +132,7 @@
 
 struct s3c64xx_spi_dma_data {
 	unsigned		ch;
-	enum dma_data_direction direction;
+	enum dma_transfer_direction direction;
 	enum dma_ch	dmach;
 	struct property		*dma_prop;
 };

@@ -1065,11 +1065,11 @@ static int __devinit s3c64xx_spi_get_dmares(
 
 	if (tx) {
 		dma_data = &sdd->tx_dma;
-		dma_data->direction = DMA_TO_DEVICE;
+		dma_data->direction = DMA_MEM_TO_DEV;
 		chan_str = "tx";
 	} else {
 		dma_data = &sdd->rx_dma;
-		dma_data->direction = DMA_FROM_DEVICE;
+		dma_data->direction = DMA_DEV_TO_MEM;
 		chan_str = "rx";
 	}