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Diffstat (limited to 'include/linux/isa.h')
-rw-r--r--include/linux/isa.h37
1 files changed, 35 insertions, 2 deletions
diff --git a/include/linux/isa.h b/include/linux/isa.h
index b0270e381..f2d025841 100644
--- a/include/linux/isa.h
+++ b/include/linux/isa.h
@@ -6,6 +6,7 @@
#define __LINUX_ISA_H
#include <linux/device.h>
+#include <linux/errno.h>
#include <linux/kernel.h>
struct isa_driver {
@@ -22,13 +23,13 @@ struct isa_driver {
#define to_isa_driver(x) container_of((x), struct isa_driver, driver)
-#ifdef CONFIG_ISA
+#ifdef CONFIG_ISA_BUS_API
int isa_register_driver(struct isa_driver *, unsigned int);
void isa_unregister_driver(struct isa_driver *);
#else
static inline int isa_register_driver(struct isa_driver *d, unsigned int i)
{
- return 0;
+ return -ENODEV;
}
static inline void isa_unregister_driver(struct isa_driver *d)
@@ -36,4 +37,36 @@ static inline void isa_unregister_driver(struct isa_driver *d)
}
#endif
+/**
+ * module_isa_driver() - Helper macro for registering a ISA driver
+ * @__isa_driver: isa_driver struct
+ * @__num_isa_dev: number of devices to register
+ *
+ * Helper macro for ISA drivers which do not do anything special in module
+ * init/exit. This eliminates a lot of boilerplate code. Each module may only
+ * use this macro once, and calling it replaces module_init and module_exit.
+ */
+#define module_isa_driver(__isa_driver, __num_isa_dev) \
+static int __init __isa_driver##_init(void) \
+{ \
+ return isa_register_driver(&(__isa_driver), __num_isa_dev); \
+} \
+module_init(__isa_driver##_init); \
+static void __exit __isa_driver##_exit(void) \
+{ \
+ isa_unregister_driver(&(__isa_driver)); \
+} \
+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 */