riscv: io: avoid null-pointer arithmetic in PIO helpers

When port I/O is not supported, exposing the port-string helpers is both
unnecessary and can make clang diagnose null-pointer arithmetic from the
PCI_IOBASE based address expression.  Keep the MMIO string helpers
available as before, but only provide the port I/O variants when
CONFIG_HAS_IOPORT is enabled.

Signed-off-by: Yunhui Cui <cuiyunhui@bytedance.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20260703122832.15984-2-cuiyunhui@bytedance.com
Signed-off-by: Paul Walmsley <pjw@kernel.org>

Author: cuiyunhui

arch/riscv/include/asm/io.h

@@ -102,12 +102,14 @@ __io_reads_ins(reads, u32, l, __io_br(), __io_ar(addr))
 #define readsw(addr, buffer, count) __readsw(addr, buffer, count)
 #define readsl(addr, buffer, count) __readsl(addr, buffer, count)
 
+#ifdef CONFIG_HAS_IOPORT
 __io_reads_ins(ins,  u8, b, __io_pbr(), __io_par(addr))
 __io_reads_ins(ins, u16, w, __io_pbr(), __io_par(addr))
 __io_reads_ins(ins, u32, l, __io_pbr(), __io_par(addr))
 #define insb(addr, buffer, count) __insb(PCI_IOBASE + (addr), buffer, count)
 #define insw(addr, buffer, count) __insw(PCI_IOBASE + (addr), buffer, count)
 #define insl(addr, buffer, count) __insl(PCI_IOBASE + (addr), buffer, count)
+#endif
 
 __io_writes_outs(writes,  u8, b, __io_bw(), __io_aw())
 __io_writes_outs(writes, u16, w, __io_bw(), __io_aw())
@@ -116,26 +118,32 @@ __io_writes_outs(writes, u32, l, __io_bw(), __io_aw())
 #define writesw(addr, buffer, count) __writesw(addr, buffer, count)
 #define writesl(addr, buffer, count) __writesl(addr, buffer, count)
 
+#ifdef CONFIG_HAS_IOPORT
 __io_writes_outs(outs,  u8, b, __io_pbw(), __io_paw())
 __io_writes_outs(outs, u16, w, __io_pbw(), __io_paw())
 __io_writes_outs(outs, u32, l, __io_pbw(), __io_paw())
 #define outsb(addr, buffer, count) __outsb(PCI_IOBASE + (addr), buffer, count)
 #define outsw(addr, buffer, count) __outsw(PCI_IOBASE + (addr), buffer, count)
 #define outsl(addr, buffer, count) __outsl(PCI_IOBASE + (addr), buffer, count)
+#endif
 
 #ifdef CONFIG_64BIT
 __io_reads_ins(reads, u64, q, __io_br(), __io_ar(addr))
 #define readsq(addr, buffer, count) __readsq(addr, buffer, count)
 
+#ifdef CONFIG_HAS_IOPORT
 __io_reads_ins(ins, u64, q, __io_pbr(), __io_par(addr))
 #define insq(addr, buffer, count) __insq(PCI_IOBASE + (addr), buffer, count)
+#endif
 
 __io_writes_outs(writes, u64, q, __io_bw(), __io_aw())
 #define writesq(addr, buffer, count) __writesq(addr, buffer, count)
 
+#ifdef CONFIG_HAS_IOPORT
 __io_writes_outs(outs, u64, q, __io_pbr(), __io_paw())
 #define outsq(addr, buffer, count) __outsq(PCI_IOBASE + (addr), buffer, count)
 #endif
+#endif
 
 #include <asm-generic/io.h>