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

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>
Signed-off-by: David S. Miller <davem@davemloft.net>

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,

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);

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);

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 */