diff options
Diffstat (limited to 'include/linux/isa.h')
| -rw-r--r-- | include/linux/isa.h | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/include/linux/isa.h b/include/linux/isa.h index e394917d18c2..5ab85281230b 100644 --- a/include/linux/isa.h +++ b/include/linux/isa.h @@ -57,4 +57,15 @@ static void __exit __isa_driver##_exit(void) \ } \ module_exit(__isa_driver##_exit); +/** + * max_num_isa_dev() - Maximum possible number registered of an ISA device + * @__ida_dev_ext: ISA device address extent + * + * The highest base address possible for an ISA device is 0x3FF; this results in + * 1024 possible base addresses. Dividing the number of possible base addresses + * by the address extent taken by each device results in the maximum number of + * devices on a system. + */ +#define max_num_isa_dev(__isa_dev_ext) (1024 / __isa_dev_ext) + #endif /* __LINUX_ISA_H */ |