1 /**
2    nsc_gpio.c
3 
4    National Semiconductor GPIO common access methods.
5 
6    struct nsc_gpio_ops abstracts the low-level access
7    operations for the GPIO units on 2 NSC chip families; the GEODE
8    integrated CPU, and the PC-8736[03456] integrated PC-peripheral
9    chips.
10 
11    The GPIO units on these chips have the same pin architecture, but
12    the access methods differ.  Thus, scx200_gpio and pc8736x_gpio
13    implement their own versions of these routines; and use the common
14    file-operations routines implemented in nsc_gpio module.
15 
16    Copyright (c) 2005 Jim Cromie <jim.cromie@gmail.com>
17 
18    NB: this work was tested on the Geode SC-1100 and PC-87366 chips.
19    NSC sold the GEODE line to AMD, and the PC-8736x line to Winbond.
20 */
21 
22 struct nsc_gpio_ops {
23 	struct module*	owner;
24 	u32	(*gpio_config)	(unsigned iminor, u32 mask, u32 bits);
25 	void	(*gpio_dump)	(struct nsc_gpio_ops *amp, unsigned iminor);
26 	int	(*gpio_get)	(unsigned iminor);
27 	void	(*gpio_set)	(unsigned iminor, int state);
28 	void	(*gpio_change)	(unsigned iminor);
29 	int	(*gpio_current)	(unsigned iminor);
30 	struct device*	dev;	/* for dev_dbg() support, set in init  */
31 };
32 
33 extern ssize_t nsc_gpio_write(struct file *file, const char __user *data,
34 			      size_t len, loff_t *ppos);
35 
36 extern ssize_t nsc_gpio_read(struct file *file, char __user *buf,
37 			     size_t len, loff_t *ppos);
38 
39 extern void nsc_gpio_dump(struct nsc_gpio_ops *amp, unsigned index);
40 
41