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