diff mbox series

[v3] isdn: hfc_{pci,sx}: Avoid empty body if statements

Message ID 20181019011103.32087-1-natechancellor@gmail.com
State Accepted, archived
Delegated to: David Miller
Headers show
Series [v3] isdn: hfc_{pci,sx}: Avoid empty body if statements | expand

Commit Message

Nathan Chancellor Oct. 19, 2018, 1:11 a.m. UTC 
Clang warns:

drivers/isdn/hisax/hfc_pci.c:131:34: error: if statement has empty body
[-Werror,-Wempty-body]
        if (Read_hfc(cs, HFCPCI_INT_S1));
                                        ^
drivers/isdn/hisax/hfc_pci.c:131:34: note: put the semicolon on a
separate line to silence this warning

In my attempt to hide the warnings because I thought they didn't serve
any purpose[1], Masahiro Yamada pointed out that {Read,Write}_hfc in
hci_pci.c should be using a standard register access method; otherwise,
the compiler will just remove the if statements.

For hfc_pci, use the versions of {Read,Write}_hfc found in
drivers/isdn/hardware/mISDN/hfc_pCI.h while converting pci_io to be
'void __iomem *' (and clean up ioremap) then remove the empty if
statements.

For hfc_sx, {Read,Write}_hfc are already use a proper register accessor
(inb, outb) so just remove the unnecessary if statements.

[1]: https://lore.kernel.org/lkml/20181016021454.11953-1-natechancellor@gmail.com/

Link: https://github.com/ClangBuiltLinux/linux/issues/66
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---

v1 -> v2:

* Remove unnecessary cast to void, just remove if statements (thanks to
  review from Masahiro).

* Clean up commit message.

v2 -> v3:

* Convert hfc_pci to properly use readb/writeb to avoid static checker
  issues.

 drivers/isdn/hisax/hfc_pci.c | 11 +++++------
 drivers/isdn/hisax/hfc_pci.h |  4 ++--
 drivers/isdn/hisax/hfc_sx.c  |  6 +++---
 drivers/isdn/hisax/hisax.h   |  2 +-
 4 files changed, 11 insertions(+), 12 deletions(-)

Comments

David Miller Oct. 23, 2018, 2:25 a.m. UTC | #1 
From: Nathan Chancellor <natechancellor@gmail.com>
Date: Thu, 18 Oct 2018 18:11:04 -0700

> Clang warns:
> 
> drivers/isdn/hisax/hfc_pci.c:131:34: error: if statement has empty body
> [-Werror,-Wempty-body]
>         if (Read_hfc(cs, HFCPCI_INT_S1));
>                                         ^
> drivers/isdn/hisax/hfc_pci.c:131:34: note: put the semicolon on a
> separate line to silence this warning
> 
> In my attempt to hide the warnings because I thought they didn't serve
> any purpose[1], Masahiro Yamada pointed out that {Read,Write}_hfc in
> hci_pci.c should be using a standard register access method; otherwise,
> the compiler will just remove the if statements.
> 
> For hfc_pci, use the versions of {Read,Write}_hfc found in
> drivers/isdn/hardware/mISDN/hfc_pCI.h while converting pci_io to be
> 'void __iomem *' (and clean up ioremap) then remove the empty if
> statements.
> 
> For hfc_sx, {Read,Write}_hfc are already use a proper register accessor
> (inb, outb) so just remove the unnecessary if statements.
> 
> [1]: https://lore.kernel.org/lkml/20181016021454.11953-1-natechancellor@gmail.com/
> 
> Link: https://github.com/ClangBuiltLinux/linux/issues/66
> Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Applied.
diff mbox series

Patch

diff --git a/drivers/isdn/hisax/hfc_pci.c b/drivers/isdn/hisax/hfc_pci.c
index 8e5b03161b2f..ea0e4c6de3fb 100644
--- a/drivers/isdn/hisax/hfc_pci.c
+++ b/drivers/isdn/hisax/hfc_pci.c
@@ -86,7 +86,7 @@  release_io_hfcpci(struct IsdnCardState *cs)
 	pci_free_consistent(cs->hw.hfcpci.dev, 0x8000,
 			    cs->hw.hfcpci.fifos, cs->hw.hfcpci.dma);
 	cs->hw.hfcpci.fifos = NULL;
-	iounmap((void *)cs->hw.hfcpci.pci_io);
+	iounmap(cs->hw.hfcpci.pci_io);
 }
 
 /********************************************************************************/
@@ -128,7 +128,7 @@  reset_hfcpci(struct IsdnCardState *cs)
 	Write_hfc(cs, HFCPCI_INT_M1, cs->hw.hfcpci.int_m1);
 
 	/* Clear already pending ints */
-	if (Read_hfc(cs, HFCPCI_INT_S1));
+	Read_hfc(cs, HFCPCI_INT_S1);
 
 	Write_hfc(cs, HFCPCI_STATES, HFCPCI_LOAD_STATE | 2);	/* HFC ST 2 */
 	udelay(10);
@@ -158,7 +158,7 @@  reset_hfcpci(struct IsdnCardState *cs)
 	/* Finally enable IRQ output */
 	cs->hw.hfcpci.int_m2 = HFCPCI_IRQ_ENABLE;
 	Write_hfc(cs, HFCPCI_INT_M2, cs->hw.hfcpci.int_m2);
-	if (Read_hfc(cs, HFCPCI_INT_S1));
+	Read_hfc(cs, HFCPCI_INT_S1);
 }
 
 /***************************************************/
@@ -1537,7 +1537,7 @@  hfcpci_bh(struct work_struct *work)
 					cs->hw.hfcpci.int_m1 &= ~HFCPCI_INTS_TIMER;
 					Write_hfc(cs, HFCPCI_INT_M1, cs->hw.hfcpci.int_m1);
 					/* Clear already pending ints */
-					if (Read_hfc(cs, HFCPCI_INT_S1));
+					Read_hfc(cs, HFCPCI_INT_S1);
 					Write_hfc(cs, HFCPCI_STATES, 4 | HFCPCI_LOAD_STATE);
 					udelay(10);
 					Write_hfc(cs, HFCPCI_STATES, 4);
@@ -1692,7 +1692,7 @@  setup_hfcpci(struct IsdnCard *card)
 		printk(KERN_WARNING "HFC-PCI: No IRQ for PCI card found\n");
 		return (0);
 	}
-	cs->hw.hfcpci.pci_io = (char *)(unsigned long)dev_hfcpci->resource[1].start;
+	cs->hw.hfcpci.pci_io = ioremap(dev_hfcpci->resource[1].start, 256);
 	printk(KERN_INFO "HiSax: HFC-PCI card manufacturer: %s card name: %s\n", id_list[i].vendor_name, id_list[i].card_name);
 
 	if (!cs->hw.hfcpci.pci_io) {
@@ -1716,7 +1716,6 @@  setup_hfcpci(struct IsdnCard *card)
 		return 0;
 	}
 	pci_write_config_dword(cs->hw.hfcpci.dev, 0x80, (u32)cs->hw.hfcpci.dma);
-	cs->hw.hfcpci.pci_io = ioremap((ulong) cs->hw.hfcpci.pci_io, 256);
 	printk(KERN_INFO
 	       "HFC-PCI: defined at mem %p fifo %p(%lx) IRQ %d HZ %d\n",
 	       cs->hw.hfcpci.pci_io,
diff --git a/drivers/isdn/hisax/hfc_pci.h b/drivers/isdn/hisax/hfc_pci.h
index 4e58700a3e61..4c3b3ba35726 100644
--- a/drivers/isdn/hisax/hfc_pci.h
+++ b/drivers/isdn/hisax/hfc_pci.h
@@ -228,8 +228,8 @@  typedef union {
 } fifo_area;
 
 
-#define Write_hfc(a, b, c) (*(((u_char *)a->hw.hfcpci.pci_io) + b) = c)
-#define Read_hfc(a, b) (*(((u_char *)a->hw.hfcpci.pci_io) + b))
+#define Write_hfc(a, b, c) (writeb(c, (a->hw.hfcpci.pci_io) + b))
+#define Read_hfc(a, b) (readb((a->hw.hfcpci.pci_io) + b))
 
 extern void main_irq_hcpci(struct BCState *bcs);
 extern void releasehfcpci(struct IsdnCardState *cs);
diff --git a/drivers/isdn/hisax/hfc_sx.c b/drivers/isdn/hisax/hfc_sx.c
index 4d3b4b2f2612..12af628d9b2c 100644
--- a/drivers/isdn/hisax/hfc_sx.c
+++ b/drivers/isdn/hisax/hfc_sx.c
@@ -381,7 +381,7 @@  reset_hfcsx(struct IsdnCardState *cs)
 	Write_hfc(cs, HFCSX_INT_M1, cs->hw.hfcsx.int_m1);
 
 	/* Clear already pending ints */
-	if (Read_hfc(cs, HFCSX_INT_S1));
+	Read_hfc(cs, HFCSX_INT_S1);
 
 	Write_hfc(cs, HFCSX_STATES, HFCSX_LOAD_STATE | 2);	/* HFC ST 2 */
 	udelay(10);
@@ -411,7 +411,7 @@  reset_hfcsx(struct IsdnCardState *cs)
 	/* Finally enable IRQ output */
 	cs->hw.hfcsx.int_m2 = HFCSX_IRQ_ENABLE;
 	Write_hfc(cs, HFCSX_INT_M2, cs->hw.hfcsx.int_m2);
-	if (Read_hfc(cs, HFCSX_INT_S2));
+	Read_hfc(cs, HFCSX_INT_S2);
 }
 
 /***************************************************/
@@ -1288,7 +1288,7 @@  hfcsx_bh(struct work_struct *work)
 					cs->hw.hfcsx.int_m1 &= ~HFCSX_INTS_TIMER;
 					Write_hfc(cs, HFCSX_INT_M1, cs->hw.hfcsx.int_m1);
 					/* Clear already pending ints */
-					if (Read_hfc(cs, HFCSX_INT_S1));
+					Read_hfc(cs, HFCSX_INT_S1);
 
 					Write_hfc(cs, HFCSX_STATES, 4 | HFCSX_LOAD_STATE);
 					udelay(10);
diff --git a/drivers/isdn/hisax/hisax.h b/drivers/isdn/hisax/hisax.h
index 338d0408b377..40080e06421c 100644
--- a/drivers/isdn/hisax/hisax.h
+++ b/drivers/isdn/hisax/hisax.h
@@ -703,7 +703,7 @@  struct hfcPCI_hw {
 	unsigned char nt_mode;
 	int nt_timer;
 	struct pci_dev *dev;
-	unsigned char *pci_io; /* start of PCI IO memory */
+	void __iomem *pci_io; /* start of PCI IO memory */
 	dma_addr_t dma; /* dma handle for Fifos */
 	void *fifos; /* FIFO memory */
 	int last_bfifo_cnt[2]; /* marker saving last b-fifo frame count */