summaryrefslogtreecommitdiffstats
path: root/firmware/target/arm/as3525/sansa-clipplus/lcd-clip-plus.c
blob: 7c0cfb53456f7522e66943b6f321e0ffe32bfa88 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
/***************************************************************************
 *             __________               __   ___.
 *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
 *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
 *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
 *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
 *                     \/            \/     \/    \/            \/
 * $Id$
 *
 * Copyright (C) 2008 François Dinel
 * Copyright (C) 2008-2009 Rafaël Carré
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
 * KIND, either express or implied.
 *
 ****************************************************************************/
#include "config.h"

#include "lcd.h"
#include "lcd-clip.h"
#include "system.h"
#include "cpu.h"

static void ssp_set_prescaler(unsigned int prescaler)
{
    int oldlevel = disable_interrupt_save(IRQ_FIQ_STATUS);
    /* must be on to write regs */
    bool ssp_enabled = bitset32(&CGU_PERI, CGU_SSP_CLOCK_ENABLE) &
                                           CGU_SSP_CLOCK_ENABLE;
    SSP_CPSR = prescaler;

    if (!ssp_enabled) /* put it back how we found it */
        bitclr32(&CGU_PERI, CGU_SSP_CLOCK_ENABLE);

    restore_irq(oldlevel);
}

int lcd_hw_init(void)
{
    bitset32(&CGU_PERI, CGU_SSP_CLOCK_ENABLE);

    ssp_set_prescaler(AS3525_SSP_PRESCALER);    /* OF = 0x10 */
    SSP_CR0 = (1<<7) | (1<<6) | 7;  /* Motorola SPI frame format, 8 bits */
    SSP_CR1 = (1<<3) | (1<<1);  /* SSP Operation enabled */
    SSP_IMSC = 0;       /* No interrupts */

    /* configure GPIO B2 (display D/C#) as output */
    GPIOB_DIR |= (1<<2);

    /* configure GPIO B3 (display type detect) as input */
    GPIOB_DIR &= ~(1<<3);

    /* reset display using GPIO A5 (display RESET#) */
    GPIOA_DIR |= (1<<5);
    GPIOA_PIN(5) = 0;
    udelay(1000);
    GPIOA_PIN(5) = (1<<5);

    /* detect display type on GPIO B3 */    
    return GPIOB_PIN(3) ? 1 : 0;
}

void lcd_write_command(int byte)
{
    while(SSP_SR & (1<<4))  /* BSY flag */
        ;

    /* LCD command mode */
    GPIOB_PIN(2) = 0;
    
    SSP_DATA = byte;
    while(SSP_SR & (1<<4))  /* BSY flag */
        ;
}

void lcd_write_cmd_triplet(int cmd1, int cmd2, int cmd3)
{
#ifndef LCD_USE_FIFO_FOR_COMMANDS
    lcd_write_command(cmd1);
    lcd_write_command(cmd2);
    lcd_write_command(cmd3);
#else
    /* combine writes to data register */
    while(SSP_SR & (1<<4))  /* BSY flag */
        ;
    /* FIFO is empty at this point */

    /* LCD command mode */
    GPIOB_PIN(2) = 0;

    /* !!makes assumption FIFO is at least (3) levels deep!! */
    SSP_DATA = cmd1;
    SSP_DATA = cmd2;
    SSP_DATA = cmd3;

    while(SSP_SR & (1<<4))  /* BSY flag */
        ;
#endif
}

void lcd_write_data(const fb_data* p_bytes, int count)
{
    /* LCD data mode */
    GPIOB_PIN(2) = (1<<2);

    while (count--)
    {
        while(!(SSP_SR & (1<<1)))   /* wait until transmit FIFO is not full */
            ;

        SSP_DATA = *p_bytes++;
    }
}

void lcd_enable_power(bool onoff)
{
#ifndef BOOTLOADER
    if (onoff)
        bitset32(&CGU_PERI, CGU_SSP_CLOCK_ENABLE);
    else
        bitclr32(&CGU_PERI, CGU_SSP_CLOCK_ENABLE);
#else
    (void) onoff;
#endif
}

#if defined(CONFIG_POWER_SAVING) && (CONFIG_POWER_SAVING & POWERSV_DISP)
/* declared in system-as3525.c */
void ams_ssp_set_low_speed(bool slow)
{
    ssp_set_prescaler(slow ? AS3525_SSP_PRESCALER_MAX : AS3525_SSP_PRESCALER);
}
#endif