xref: /openbmc/linux/drivers/parport/parport_gsc.h (revision 3ddc8b84)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *	Low-level parallel-support for PC-style hardware integrated in the
4  *	LASI-Controller (on GSC-Bus) for HP-PARISC Workstations
5  *
6  *	(C) 1999-2001 by Helge Deller <deller@gmx.de>
7  *
8  * based on parport_pc.c by
9  * 	    Grant Guenther <grant@torque.net>
10  * 	    Phil Blundell <Philip.Blundell@pobox.com>
11  *          Tim Waugh <tim@cyberelk.demon.co.uk>
12  *	    Jose Renau <renau@acm.org>
13  *          David Campbell
14  *          Andrea Arcangeli
15  */
16 
17 #ifndef	__DRIVERS_PARPORT_PARPORT_GSC_H
18 #define	__DRIVERS_PARPORT_PARPORT_GSC_H
19 
20 #include <asm/io.h>
21 #include <linux/delay.h>
22 
23 #undef	DEBUG_PARPORT	/* undefine for production */
24 #define DELAY_TIME 	0
25 
26 #if DELAY_TIME == 0
27 #define parport_readb	gsc_readb
28 #define parport_writeb	gsc_writeb
29 #else
30 static __inline__ unsigned char parport_readb( unsigned long port )
31 {
32     udelay(DELAY_TIME);
33     return gsc_readb(port);
34 }
35 
36 static __inline__ void parport_writeb( unsigned char value, unsigned long port )
37 {
38     gsc_writeb(value,port);
39     udelay(DELAY_TIME);
40 }
41 #endif
42 
43 /* --- register definitions ------------------------------- */
44 
45 #define EPPDATA(p)  ((p)->base    + 0x4)
46 #define EPPADDR(p)  ((p)->base    + 0x3)
47 #define CONTROL(p)  ((p)->base    + 0x2)
48 #define STATUS(p)   ((p)->base    + 0x1)
49 #define DATA(p)     ((p)->base    + 0x0)
50 
51 struct parport_gsc_private {
52 	/* Contents of CTR. */
53 	unsigned char ctr;
54 
55 	/* Bitmask of writable CTR bits. */
56 	unsigned char ctr_writable;
57 
58 	/* Number of bytes per portword. */
59 	int pword;
60 
61 	/* Not used yet. */
62 	int readIntrThreshold;
63 	int writeIntrThreshold;
64 
65 	/* buffer suitable for DMA, if DMA enabled */
66 	struct pci_dev *dev;
67 };
68 
69 static inline void parport_gsc_write_data(struct parport *p, unsigned char d)
70 {
71 #ifdef DEBUG_PARPORT
72 	printk(KERN_DEBUG "%s(%p,0x%02x)\n", __func__, p, d);
73 #endif
74 	parport_writeb(d, DATA(p));
75 }
76 
77 static inline unsigned char parport_gsc_read_data(struct parport *p)
78 {
79 	unsigned char val = parport_readb (DATA (p));
80 #ifdef DEBUG_PARPORT
81 	printk(KERN_DEBUG "%s(%p) = 0x%02x\n", __func__, p, val);
82 #endif
83 	return val;
84 }
85 
86 /* __parport_gsc_frob_control differs from parport_gsc_frob_control in that
87  * it doesn't do any extra masking. */
88 static inline unsigned char __parport_gsc_frob_control(struct parport *p,
89 							unsigned char mask,
90 							unsigned char val)
91 {
92 	struct parport_gsc_private *priv = p->physport->private_data;
93 	unsigned char ctr = priv->ctr;
94 #ifdef DEBUG_PARPORT
95 	printk(KERN_DEBUG "%s(%02x,%02x): %02x -> %02x\n",
96 	       __func__, mask, val,
97 	       ctr, ((ctr & ~mask) ^ val) & priv->ctr_writable);
98 #endif
99 	ctr = (ctr & ~mask) ^ val;
100 	ctr &= priv->ctr_writable; /* only write writable bits. */
101 	parport_writeb (ctr, CONTROL (p));
102 	priv->ctr = ctr;	/* Update soft copy */
103 	return ctr;
104 }
105 
106 static inline void parport_gsc_data_reverse(struct parport *p)
107 {
108 	__parport_gsc_frob_control (p, 0x20, 0x20);
109 }
110 
111 static inline void parport_gsc_data_forward(struct parport *p)
112 {
113 	__parport_gsc_frob_control (p, 0x20, 0x00);
114 }
115 
116 static inline void parport_gsc_write_control(struct parport *p,
117 						 unsigned char d)
118 {
119 	const unsigned char wm = (PARPORT_CONTROL_STROBE |
120 				  PARPORT_CONTROL_AUTOFD |
121 				  PARPORT_CONTROL_INIT |
122 				  PARPORT_CONTROL_SELECT);
123 
124 	/* Take this out when drivers have adapted to newer interface. */
125 	if (d & 0x20) {
126 		printk(KERN_DEBUG "%s (%s): use data_reverse for this!\n",
127 		       p->name, p->cad->name);
128 		parport_gsc_data_reverse (p);
129 	}
130 
131 	__parport_gsc_frob_control (p, wm, d & wm);
132 }
133 
134 static inline unsigned char parport_gsc_read_control(struct parport *p)
135 {
136 	const unsigned char rm = (PARPORT_CONTROL_STROBE |
137 				  PARPORT_CONTROL_AUTOFD |
138 				  PARPORT_CONTROL_INIT |
139 				  PARPORT_CONTROL_SELECT);
140 	const struct parport_gsc_private *priv = p->physport->private_data;
141 	return priv->ctr & rm; /* Use soft copy */
142 }
143 
144 static inline unsigned char parport_gsc_frob_control(struct parport *p,
145 							unsigned char mask,
146 							unsigned char val)
147 {
148 	const unsigned char wm = (PARPORT_CONTROL_STROBE |
149 				  PARPORT_CONTROL_AUTOFD |
150 				  PARPORT_CONTROL_INIT |
151 				  PARPORT_CONTROL_SELECT);
152 
153 	/* Take this out when drivers have adapted to newer interface. */
154 	if (mask & 0x20) {
155 		printk(KERN_DEBUG "%s (%s): use data_%s for this!\n",
156 		       p->name, p->cad->name,
157 		       (val & 0x20) ? "reverse" : "forward");
158 		if (val & 0x20)
159 			parport_gsc_data_reverse (p);
160 		else
161 			parport_gsc_data_forward (p);
162 	}
163 
164 	/* Restrict mask and val to control lines. */
165 	mask &= wm;
166 	val &= wm;
167 
168 	return __parport_gsc_frob_control (p, mask, val);
169 }
170 
171 static inline unsigned char parport_gsc_read_status(struct parport *p)
172 {
173 	return parport_readb (STATUS(p));
174 }
175 
176 static inline void parport_gsc_disable_irq(struct parport *p)
177 {
178 	__parport_gsc_frob_control (p, 0x10, 0x00);
179 }
180 
181 static inline void parport_gsc_enable_irq(struct parport *p)
182 {
183 	__parport_gsc_frob_control (p, 0x10, 0x10);
184 }
185 
186 extern void parport_gsc_release_resources(struct parport *p);
187 
188 extern int parport_gsc_claim_resources(struct parport *p);
189 
190 extern void parport_gsc_init_state(struct pardevice *, struct parport_state *s);
191 
192 extern void parport_gsc_save_state(struct parport *p, struct parport_state *s);
193 
194 extern void parport_gsc_restore_state(struct parport *p, struct parport_state *s);
195 
196 extern void parport_gsc_inc_use_count(void);
197 
198 extern void parport_gsc_dec_use_count(void);
199 
200 #endif	/* __DRIVERS_PARPORT_PARPORT_GSC_H */
201