1 /*
2  * Picvue PVC160206 display driver
3  *
4  * Brian Murphy <brian@murphy.dk>
5  *
6  */
7 #include <linux/kernel.h>
8 #include <linux/delay.h>
9 #include <asm/bootinfo.h>
10 #include <asm/lasat/lasat.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/errno.h>
14 #include <linux/string.h>
15 
16 #include "picvue.h"
17 
18 #define PVC_BUSY		0x80
19 #define PVC_NLINES		2
20 #define PVC_DISPMEM		80
21 #define PVC_LINELEN		PVC_DISPMEM / PVC_NLINES
22 
23 struct pvc_defs *picvue;
24 
pvc_reg_write(u32 val)25 static void pvc_reg_write(u32 val)
26 {
27 	*picvue->reg = val;
28 }
29 
pvc_reg_read(void)30 static u32 pvc_reg_read(void)
31 {
32 	u32 tmp = *picvue->reg;
33 	return tmp;
34 }
35 
pvc_write_byte(u32 data,u8 byte)36 static void pvc_write_byte(u32 data, u8 byte)
37 {
38 	data |= picvue->e;
39 	pvc_reg_write(data);
40 	data &= ~picvue->data_mask;
41 	data |= byte << picvue->data_shift;
42 	pvc_reg_write(data);
43 	ndelay(220);
44 	pvc_reg_write(data & ~picvue->e);
45 	ndelay(220);
46 }
47 
pvc_read_byte(u32 data)48 static u8 pvc_read_byte(u32 data)
49 {
50 	u8 byte;
51 
52 	data |= picvue->e;
53 	pvc_reg_write(data);
54 	ndelay(220);
55 	byte = (pvc_reg_read() & picvue->data_mask) >> picvue->data_shift;
56 	data &= ~picvue->e;
57 	pvc_reg_write(data);
58 	ndelay(220);
59 	return byte;
60 }
61 
pvc_read_data(void)62 static u8 pvc_read_data(void)
63 {
64 	u32 data = pvc_reg_read();
65 	u8 byte;
66 	data |= picvue->rw;
67 	data &= ~picvue->rs;
68 	pvc_reg_write(data);
69 	ndelay(40);
70 	byte = pvc_read_byte(data);
71 	data |= picvue->rs;
72 	pvc_reg_write(data);
73 	return byte;
74 }
75 
76 #define TIMEOUT 1000
pvc_wait(void)77 static int pvc_wait(void)
78 {
79 	int i = TIMEOUT;
80 	int err = 0;
81 
82 	while ((pvc_read_data() & PVC_BUSY) && i)
83 		i--;
84 	if (i == 0)
85 		err = -ETIME;
86 
87 	return err;
88 }
89 
90 #define MODE_INST 0
91 #define MODE_DATA 1
pvc_write(u8 byte,int mode)92 static void pvc_write(u8 byte, int mode)
93 {
94 	u32 data = pvc_reg_read();
95 	data &= ~picvue->rw;
96 	if (mode == MODE_DATA)
97 		data |= picvue->rs;
98 	else
99 		data &= ~picvue->rs;
100 	pvc_reg_write(data);
101 	ndelay(40);
102 	pvc_write_byte(data, byte);
103 	if (mode == MODE_DATA)
104 		data &= ~picvue->rs;
105 	else
106 		data |= picvue->rs;
107 	pvc_reg_write(data);
108 	pvc_wait();
109 }
110 
pvc_write_string(const unsigned char * str,u8 addr,int line)111 void pvc_write_string(const unsigned char *str, u8 addr, int line)
112 {
113 	int i = 0;
114 
115 	if (line > 0 && (PVC_NLINES > 1))
116 		addr += 0x40 * line;
117 	pvc_write(0x80 | addr, MODE_INST);
118 
119 	while (*str != 0 && i < PVC_LINELEN) {
120 		pvc_write(*str++, MODE_DATA);
121 		i++;
122 	}
123 }
124 
pvc_write_string_centered(const unsigned char * str,int line)125 void pvc_write_string_centered(const unsigned char *str, int line)
126 {
127 	int len = strlen(str);
128 	u8 addr;
129 
130 	if (len > PVC_VISIBLE_CHARS)
131 		addr = 0;
132 	else
133 		addr = (PVC_VISIBLE_CHARS - strlen(str))/2;
134 
135 	pvc_write_string(str, addr, line);
136 }
137 
pvc_dump_string(const unsigned char * str)138 void pvc_dump_string(const unsigned char *str)
139 {
140 	int len = strlen(str);
141 
142 	pvc_write_string(str, 0, 0);
143 	if (len > PVC_VISIBLE_CHARS)
144 		pvc_write_string(&str[PVC_VISIBLE_CHARS], 0, 1);
145 }
146 
147 #define BM_SIZE			8
148 #define MAX_PROGRAMMABLE_CHARS	8
pvc_program_cg(int charnum,u8 bitmap[BM_SIZE])149 int pvc_program_cg(int charnum, u8 bitmap[BM_SIZE])
150 {
151 	int i;
152 	int addr;
153 
154 	if (charnum > MAX_PROGRAMMABLE_CHARS)
155 		return -ENOENT;
156 
157 	addr = charnum * 8;
158 	pvc_write(0x40 | addr, MODE_INST);
159 
160 	for (i = 0; i < BM_SIZE; i++)
161 		pvc_write(bitmap[i], MODE_DATA);
162 	return 0;
163 }
164 
165 #define FUNC_SET_CMD	0x20
166 #define  EIGHT_BYTE	(1 << 4)
167 #define  FOUR_BYTE	0
168 #define  TWO_LINES	(1 << 3)
169 #define  ONE_LINE	0
170 #define  LARGE_FONT	(1 << 2)
171 #define  SMALL_FONT	0
172 
pvc_funcset(u8 cmd)173 static void pvc_funcset(u8 cmd)
174 {
175 	pvc_write(FUNC_SET_CMD | (cmd & (EIGHT_BYTE|TWO_LINES|LARGE_FONT)),
176 		  MODE_INST);
177 }
178 
179 #define ENTRYMODE_CMD		0x4
180 #define  AUTO_INC		(1 << 1)
181 #define  AUTO_DEC		0
182 #define  CURSOR_FOLLOWS_DISP	(1 << 0)
183 
pvc_entrymode(u8 cmd)184 static void pvc_entrymode(u8 cmd)
185 {
186 	pvc_write(ENTRYMODE_CMD | (cmd & (AUTO_INC|CURSOR_FOLLOWS_DISP)),
187 		  MODE_INST);
188 }
189 
190 #define DISP_CNT_CMD	0x08
191 #define  DISP_OFF	0
192 #define  DISP_ON	(1 << 2)
193 #define  CUR_ON		(1 << 1)
194 #define  CUR_BLINK	(1 << 0)
pvc_dispcnt(u8 cmd)195 void pvc_dispcnt(u8 cmd)
196 {
197 	pvc_write(DISP_CNT_CMD | (cmd & (DISP_ON|CUR_ON|CUR_BLINK)), MODE_INST);
198 }
199 
200 #define MOVE_CMD	0x10
201 #define  DISPLAY	(1 << 3)
202 #define  CURSOR		0
203 #define  RIGHT		(1 << 2)
204 #define  LEFT		0
pvc_move(u8 cmd)205 void pvc_move(u8 cmd)
206 {
207 	pvc_write(MOVE_CMD | (cmd & (DISPLAY|RIGHT)), MODE_INST);
208 }
209 
210 #define CLEAR_CMD	0x1
pvc_clear(void)211 void pvc_clear(void)
212 {
213 	pvc_write(CLEAR_CMD, MODE_INST);
214 }
215 
216 #define HOME_CMD	0x2
pvc_home(void)217 void pvc_home(void)
218 {
219 	pvc_write(HOME_CMD, MODE_INST);
220 }
221 
pvc_init(void)222 int pvc_init(void)
223 {
224 	u8 cmd = EIGHT_BYTE;
225 
226 	if (PVC_NLINES == 2)
227 		cmd |= (SMALL_FONT|TWO_LINES);
228 	else
229 		cmd |= (LARGE_FONT|ONE_LINE);
230 	pvc_funcset(cmd);
231 	pvc_dispcnt(DISP_ON);
232 	pvc_entrymode(AUTO_INC);
233 
234 	pvc_clear();
235 	pvc_write_string_centered("Display", 0);
236 	pvc_write_string_centered("Initialized", 1);
237 
238 	return 0;
239 }
240 
241 module_init(pvc_init);
242 MODULE_LICENSE("GPL");
243