[i2c] [PATCH] basic gpio_chip support for 16-bit PCA9539 GPIO expander

[David Brownell]

Kconfig needs to say that it depends on GPIO_LIB...

And none of the IRQ logic should be included in modular builds;
see below.

- Dave



scripts/kconfig/conf -s arch/arm/Kconfig
drivers/dma/Kconfig:22:warning: 'select' used by config symbol 'INTEL_IOATDMA' refers to undefined symbol 'DCA'
  CHK     include/linux/version.h
  SYMLINK include/asm-arm/arch -> include/asm-arm/arch-omap
make[1]: `include/asm-arm/mach-types.h' is up to date.
  CHK     include/linux/utsrelease.h
  CALL    scripts/checksyscalls.sh
<stdin>:1097:2: warning: #warning syscall fadvise64 not implemented
<stdin>:1265:2: warning: #warning syscall migrate_pages not implemented
<stdin>:1321:2: warning: #warning syscall pselect6 not implemented
<stdin>:1325:2: warning: #warning syscall ppoll not implemented
<stdin>:1365:2: warning: #warning syscall epoll_pwait not implemented
  CHK     include/linux/compile.h
  GZIP    kernel/config_data.gz
  IKCFG   kernel/config_data.h
  CC      kernel/configs.o
  LD      kernel/built-in.o
  CC [M]  drivers/i2c/chips/pca9539.o
  GEN     .version
  CHK     include/linux/compile.h
  UPD     include/linux/compile.h
  CC      init/version.o
  LD      init/built-in.o
  LD      .tmp_vmlinux1
  KSYM    .tmp_kallsyms1.S
  AS      .tmp_kallsyms1.o
  LD      .tmp_vmlinux2
  KSYM    .tmp_kallsyms2.S
  AS      .tmp_kallsyms2.o
  LD      vmlinux.o
  MODPOST vmlinux.o
  LD      vmlinux
  SYSMAP  System.map
  SYSMAP  .tmp_System.map
  OBJCOPY arch/arm/boot/Image
  Kernel: arch/arm/boot/Image is ready
  GZIP    arch/arm/boot/compressed/piggy.gz
  AS      arch/arm/boot/compressed/piggy.o
  LD      arch/arm/boot/compressed/vmlinux
  OBJCOPY arch/arm/boot/zImage
  Kernel: arch/arm/boot/zImage is ready
  Building modules, stage 2.
  MODPOST 25 modules
ERROR: "irq_exit" [drivers/i2c/chips/pca9539.ko] undefined!
ERROR: "irq_enter" [drivers/i2c/chips/pca9539.ko] undefined!
ERROR: "handle_edge_irq" [drivers/i2c/chips/pca9539.ko] undefined!
ERROR: "set_irq_flags" [drivers/i2c/chips/pca9539.ko] undefined!
ERROR: "__set_irq_handler" [drivers/i2c/chips/pca9539.ko] undefined!
ERROR: "irq_desc" [drivers/i2c/chips/pca9539.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2