Sansa c200v2 : lcd & backlight support, using the c200v1 lcd driver

The LCD driver is unified and lcd_send_command now takes 2 arguments : the command and its argument.
    If there is no argument, it's set to 0 and a NOP command is issued
    If there is more than one argument (set X/Y address), the 2nd argument is sent as a 2nd command, and a NOP command is issued after it.
    Benefit : c200v2 transfers the command and the argument in one 16 bits transfer
    Performance should not be affected since commands without argument are only used in lcd_init() and lcd_enable()

lcd_send_data() now transfers whole lines (or columns) instead of single pixels
yuv is disabled for c200v2 for now

Some buttons can be read, including left button (bit 6 of DBOP_DIN), but for some reason they have no effect in rockbox: to be investigated

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21321 a1c6a512-1295-4272-9138-f99709370657

7 files changed, 282 insertions, 594 deletions

diff --git a/firmware/SOURCES b/firmware/SOURCES
index 48e4c77760..78f13a9444 100644
--- a/firmware/SOURCES
+++ b/firmware/SOURCES
@@ -535,7 +535,7 @@ target/arm/powermgmt-ascodec.c
 target/arm/usb-fw-pp502x.c
 target/arm/sandisk/backlight-c200_e200.c
 target/arm/sandisk/power-c200_e200.c
-target/arm/sandisk/sansa-c200/lcd-c200.c
+target/arm/lcd-c200_c200v2.c
 target/arm/sandisk/sansa-c200/lcd-as-c200.S
 target/arm/sandisk/sansa-c200/button-c200.c
 target/arm/sandisk/sansa-c200/powermgmt-c200.c
@@ -1137,7 +1137,7 @@ target/arm/as3525/sansa-e200v2/powermgmt-e200v2.c
 
 #ifdef SANSA_C200V2
 #ifndef SIMULATOR
-target/arm/as3525/sansa-c200v2/lcd-c200v2.c
+target/arm/lcd-c200_c200v2.c
 target/arm/as3525/sansa-c200v2/button-c200v2.c
 target/arm/as3525/sansa-c200v2/backlight-c200v2.c
 #ifndef BOOTLOADER
diff --git a/firmware/export/config-c200v2.h b/firmware/export/config-c200v2.h
index 775a39fc4c..03f6ac0698 100644
--- a/firmware/export/config-c200v2.h
+++ b/firmware/export/config-c200v2.h
@@ -1,21 +1,25 @@
 /*
- * This config file is for the Sandisk Sansa e200
+ * This config file is for the Sandisk Sansa c200v2
  */
 #define TARGET_TREE /* this target is using the target tree system */
 
 /* For Rolo and boot loader */
 #define MODEL_NUMBER 44
 #define MODEL_NAME   "Sandisk Sansa c200v2 series"
+#define FIRMWARE_OFFSET_FILE_DATA 8
+#define FIRMWARE_OFFSET_FILE_CRC 0
+
+#if 0
 
 #define HW_SAMPR_CAPS       (SAMPR_CAP_44)
 
-#if 0
 /* define this if you have recording possibility */
 #define HAVE_RECORDING
 
 #define REC_SAMPR_CAPS      (SAMPR_CAP_22)
 #define REC_FREQ_DEFAULT    REC_FREQ_22 /* Default is not 44.1kHz */
 #define REC_SAMPR_DEFAULT   SAMPR_22
+
 #endif
 
 /* Define bitmask of input sources - recordable bitmask can be defined
@@ -55,7 +59,6 @@
 #define LCD_DEPTH  16   /* 65536 colours */
 #define LCD_PIXELFORMAT RGB565 /* rgb565 */
 
-#ifndef BOOTLOADER
 /* define this if you have LCD enable function */
 #define HAVE_LCD_ENABLE
 
@@ -63,22 +66,21 @@
    should be defined as well. */
 /* TODO: #define HAVE_LCD_SLEEP */
 /* TODO: #define HAVE_LCD_SLEEP_SETTING <= optional */
-#endif
+
 /* define this if you can flip your LCD */
 #define HAVE_LCD_FLIP
 
 /* define this if you can invert the colours on your LCD */
 /* TODO: #define HAVE_LCD_INVERT */
 
-#if 0
 /* Define this if your LCD can set contrast */
 #define HAVE_LCD_CONTRAST
 
 #define MIN_CONTRAST_SETTING        0
 #define MAX_CONTRAST_SETTING        255
 #define DEFAULT_CONTRAST_SETTING    85
-#endif
-/* #define IRAM_LCDFRAMEBUFFER IDATA_ATTR *//* put the lcd frame buffer in IRAM */
+
+ #define IRAM_LCDFRAMEBUFFER IDATA_ATTR /* put the lcd frame buffer in IRAM */
 
 #define CONFIG_KEYPAD SANSA_C200_PAD
 
@@ -91,7 +93,7 @@
 /* There is no hardware tone control */
 #define HAVE_SW_TONE_CONTROLS
 
-/* The PP5024 has a built-in AustriaMicrosystems AS3514 */
+/* The AS3525 has a built-in AS3514 (or a newer version) */
 #define HAVE_AS3514
 
 /* define this if you have a real-time clock */
@@ -114,7 +116,7 @@
 #define AB_REPEAT_ENABLE 1
 
 /* FM Tuner - suspected to be the SI4702 */
-#define CONFIG_TUNER SI4700
+//#define CONFIG_TUNER SI4700
 /* #define HAVE_TUNER_PWR_CTRL */
 
 /* Define this for LCD backlight available */
@@ -159,30 +161,22 @@
 #define ROM_START 0x00000000
 
 /* Define this to the CPU frequency */
-#define CPU_FREQ      75000000
+#define CPU_FREQ      250000000
 
 /* Type of LCD TODO: hopefully the same as the x5 but check this*/
 #define CONFIG_LCD LCD_C200
 
-/* Offset ( in the firmware file's header ) to the file CRC and data. These are
-   only used when loading the old format rockbox.e200 file */
-#define FIRMWARE_OFFSET_FILE_CRC    0x0
-#define FIRMWARE_OFFSET_FILE_DATA   0x8
-
 #define USB_HANDLED_BY_OF
 
 #ifndef BOOTLOADER
-#define HAVE_MULTIVOLUME
-#define HAVE_HOTSWAP
+//#define HAVE_MULTIVOLUME
+//#define HAVE_HOTSWAP
 #endif
 
-/* USB On-the-go */
-#define CONFIG_USBOTG USBOTG_ARC
-
 /* enable these for the experimental usb stack */
 //#define HAVE_USBSTACK
 //#define USB_VENDOR_ID 0x0781
-//#define USB_PRODUCT_ID 0x7450
+//#define USB_PRODUCT_ID 0x7452
 /* Virtual LED (icon) */
 #define CONFIG_LED LED_VIRTUAL
 
diff --git a/firmware/target/arm/as3525/sansa-c200v2/backlight-c200v2.c b/firmware/target/arm/as3525/sansa-c200v2/backlight-c200v2.c
index f036792fc0..858e9aed49 100644
--- a/firmware/target/arm/as3525/sansa-c200v2/backlight-c200v2.c
+++ b/firmware/target/arm/as3525/sansa-c200v2/backlight-c200v2.c
@@ -26,8 +26,12 @@
 #include "ascodec-target.h"
 #include "as3514.h"
 
-/* TODO: This file is copy & pasted from backlight-e200v2-fuze.c, as I think
- * it'll be the same for c200v2; prove it */
+bool _backlight_init(void)
+{
+    GPIOA_DIR |= 1<<5;
+    return true;
+}
+
 void _backlight_set_brightness(int brightness)
 {
     if (brightness > 0)
@@ -41,12 +45,12 @@ void _backlight_on(void)
 #ifdef HAVE_LCD_ENABLE
     lcd_enable(true); /* power on lcd + visible display */
 #endif
-    ascodec_write(AS3514_DCDC15, backlight_brightness);
+    GPIOA_PIN(5) = 1<<5;
 }
 
 void _backlight_off(void)
 {
-    ascodec_write(AS3514_DCDC15, 0x0);
+    GPIOA_PIN(5) = 0;
 #ifdef HAVE_LCD_ENABLE
     lcd_enable(false); /* power off visible display */
 #endif
diff --git a/firmware/target/arm/as3525/sansa-c200v2/backlight-target.h b/firmware/target/arm/as3525/sansa-c200v2/backlight-target.h
index e8a60fa881..06076dd39f 100644
--- a/firmware/target/arm/as3525/sansa-c200v2/backlight-target.h
+++ b/firmware/target/arm/as3525/sansa-c200v2/backlight-target.h
@@ -21,7 +21,9 @@
 #ifndef BACKLIGHT_TARGET_H
 #define BACKLIGHT_TARGET_H
 
-#define _backlight_init() true
+#include <stdbool.h>
+
+bool _backlight_init(void);
 void _backlight_on(void);
 void _backlight_off(void);
 void _backlight_set_brightness(int brightness);
diff --git a/firmware/target/arm/as3525/sansa-c200v2/button-c200v2.c b/firmware/target/arm/as3525/sansa-c200v2/button-c200v2.c
index 86a6eb0c73..d3504c97e9 100644
--- a/firmware/target/arm/as3525/sansa-c200v2/button-c200v2.c
+++ b/firmware/target/arm/as3525/sansa-c200v2/button-c200v2.c
@@ -19,47 +19,70 @@
  *
  ****************************************************************************/
 
-/* Taken from button-h10.c by Barry Wardell and reverse engineering by MrH. */
-
 #include "system.h"
+#include "button-target.h"
 #include "button.h"
 #include "backlight.h"
 #include "powermgmt.h"
 
 
-#ifndef BOOTLOADER
-/* Buttons */
+unsigned short _dbop_din    = 0;
+
+/* in the lcd driver */
+extern bool lcd_button_support(void);
+
 static bool hold_button     = false;
+#ifndef BOOTLOADER
 static bool hold_button_old = false;
-#define _button_hold() hold_button
-#else
-#define _button_hold() false  /* FIXME */
-#endif /* BOOTLOADER */
-static int  int_btn         = BUTTON_NONE;
+#endif
 
 void button_init_device(void)
 {
+    GPIOA_DIR &= ~(1<<3);
 }
 
 bool button_hold(void)
 {
-    return _button_hold();
+    return hold_button;
+}
+
+static void button_read_dbop(void)
+{
+    /* Set up dbop for input */
+    DBOP_CTRL |= (1<<19);                /* Tri-state DBOP on read cycle */
+    DBOP_CTRL &= ~(1<<16);               /* disable output (1:write enabled) */
+    DBOP_TIMPOL_01 = 0xe167e167;         /* Set Timing & Polarity regs 0 & 1 */
+    DBOP_TIMPOL_23 = 0xe167006e;         /* Set Timing & Polarity regs 2 & 3 */
+
+    int i = 50;
+    while(i--) asm volatile ("nop\n");
+
+    DBOP_CTRL |= (1<<15);                /* start read */
+    while (!(DBOP_STAT & (1<<16)));      /* wait for valid data */
+
+    _dbop_din = DBOP_DIN;                /* Read dbop data*/
+
+    /* Reset dbop for output */
+    DBOP_TIMPOL_01 = 0x6e167;            /* Set Timing & Polarity regs 0 & 1 */
+    DBOP_TIMPOL_23 = 0xa167e06f;         /* Set Timing & Polarity regs 2 & 3 */
+    DBOP_CTRL |= (1<<16);                /* Enable output (0:write disable)  */
+    DBOP_CTRL &= ~(1<<19);               /* Tri-state when no active write */
 }
 
-/* device buttons */
-void button_int(void)
+/*
+ * Get button pressed from hardware
+ */
+int button_read_device(void)
 {
-    int delay = 0x50;
+    int delay;
     int dir_save_c = 0;
     int afsel_save_c = 0;
-
-    int_btn = BUTTON_NONE;
+    int btn = BUTTON_NONE;
 
     /* Save the current direction and afsel */
     dir_save_c = GPIOC_DIR;
     afsel_save_c = GPIOC_AFSEL;
 
-    GPIOA_DIR &= ~(1<<3);
     GPIOC_AFSEL &= ~(1<<6|1<<5|1<<4|1<<3);
     GPIOC_DIR |= (1<<6|1<<5|1<<4|1<<3);
 
@@ -72,32 +95,32 @@ void button_int(void)
     GPIOC_PIN(3) = (1<<3);
     GPIOC_DIR &= ~(1<<6|1<<5|1<<4|1<<3);
 
-    while(delay--);
+    delay = 100;
+    while(delay--)
+        asm volatile("nop\n");
     
     /* direct GPIO connections */
     if (GPIOA_PIN(3))
-        int_btn |= BUTTON_POWER;
+        btn |= BUTTON_POWER;
     if (!GPIOC_PIN(6))
-        int_btn |= BUTTON_RIGHT;
+        btn |= BUTTON_RIGHT;
     if (!GPIOC_PIN(5))
-        int_btn |= BUTTON_UP;
+        btn |= BUTTON_UP;
     if (!GPIOC_PIN(4))
-        int_btn |= BUTTON_SELECT;
+        btn |= BUTTON_SELECT;
     if (!GPIOC_PIN(3))
-        int_btn |= BUTTON_DOWN;
+        btn |= BUTTON_DOWN;
 
     /* return to settings needed for lcd */
     GPIOC_DIR = dir_save_c;
     GPIOC_AFSEL = afsel_save_c;
-}
 
-/*
- * Get button pressed from hardware
- */
-int button_read_device(void)
-{
-    /* Read buttons directly */
-    button_int();
+    if(lcd_button_support())
+        button_read_dbop();
+
+    if(_dbop_din & (1<<6))
+        btn |= BUTTON_LEFT;
+
 #ifndef BOOTLOADER
     /* light handling */
     if (hold_button != hold_button_old)
@@ -107,5 +130,5 @@ int button_read_device(void)
     }
 #endif /* BOOTLOADER */
 
-    return int_btn;
+    return btn;
 }
diff --git a/firmware/target/arm/as3525/sansa-c200v2/lcd-c200v2.c b/firmware/target/arm/as3525/sansa-c200v2/lcd-c200v2.c
deleted file mode 100644
index e16b082ce5..0000000000
--- a/firmware/target/arm/as3525/sansa-c200v2/lcd-c200v2.c
+++ /dev/null
@@ -1,429 +0,0 @@
-/***************************************************************************
- *             __________               __   ___.
- *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
- *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
- *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
- *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
- *                     \/            \/     \/    \/            \/
- * $Id: lcd-e200v2.c 19453 2008-12-16 02:50:39Z saratoga $
- *
- * Copyright (C) 2004 by Linus Nielsen Feltzing
- *
- * 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.
- *
- ****************************************************************************/
-
-/* FIXME: Copied from e200v2 lcd driver, unlikely to work, but maybe */
-
-#include "config.h"
-
-#include "cpu.h"
-#include "lcd.h"
-#include "kernel.h"
-#include "thread.h"
-#include <string.h>
-#include <stdlib.h>
-#include "file.h"
-#include "debug.h"
-#include "system.h"
-#include "font.h"
-#include "bidi.h"
-#include "clock-target.h"
-
-static bool display_on = false; /* is the display turned on? */
-static bool display_flipped = false;
-static int y_offset = 0; /* needed for flip */
-
-/* register defines */
-#define R_START_OSC             0x00
-#define R_DRV_OUTPUT_CONTROL    0x01
-#define R_DRV_WAVEFORM_CONTROL  0x02
-#define R_ENTRY_MODE            0x03
-#define R_COMPARE_REG1          0x04
-#define R_COMPARE_REG2          0x05
-
-#define R_DISP_CONTROL1     0x07
-#define R_DISP_CONTROL2     0x08
-#define R_DISP_CONTROL3     0x09
-
-#define R_FRAME_CYCLE_CONTROL 0x0b
-#define R_EXT_DISP_IF_CONTROL 0x0c
-
-#define R_POWER_CONTROL1    0x10
-#define R_POWER_CONTROL2    0x11
-#define R_POWER_CONTROL3    0x12
-#define R_POWER_CONTROL4    0x13
-
-#define R_RAM_ADDR_SET  0x21
-#define R_WRITE_DATA_2_GRAM 0x22
-
-#define R_GAMMA_FINE_ADJ_POS1   0x30
-#define R_GAMMA_FINE_ADJ_POS2   0x31
-#define R_GAMMA_FINE_ADJ_POS3   0x32
-#define R_GAMMA_GRAD_ADJ_POS    0x33
-
-#define R_GAMMA_FINE_ADJ_NEG1   0x34
-#define R_GAMMA_FINE_ADJ_NEG2   0x35
-#define R_GAMMA_FINE_ADJ_NEG3   0x36
-#define R_GAMMA_GRAD_ADJ_NEG    0x37
-
-#define R_GAMMA_AMP_ADJ_RES_POS     0x38
-#define R_GAMMA_AMP_AVG_ADJ_RES_NEG 0x39 
-
-#define R_GATE_SCAN_POS         0x40
-#define R_VERT_SCROLL_CONTROL   0x41
-#define R_1ST_SCR_DRV_POS       0x42
-#define R_2ND_SCR_DRV_POS       0x43
-#define R_HORIZ_RAM_ADDR_POS    0x44
-#define R_VERT_RAM_ADDR_POS     0x45
-
-#define R_ENTRY_MODE_HORZ 0x7030
-#define R_ENTRY_MODE_VERT 0x7038
-#define R_ENTRY_MODE_SOLID_VERT  0x1038
-
-/* TODO: Implement this function */
-static void lcd_delay(int x)
-{
-    /* This is just arbitrary - the OF does something more complex */
-    x *= 1024;
-    while (x--);
-}
-
-/* DBOP initialisation, do what OF does */
-static void ams3525_dbop_init(void)
-{
-    CGU_DBOP = (1<<3) | AS3525_DBOP_DIV;
-
-    DBOP_TIMPOL_01 = 0xe167e167;
-    DBOP_TIMPOL_23 = 0xe167006e;
-    DBOP_CTRL = 0x41008;
-
-    GPIOB_AFSEL = 0xfc;
-    GPIOC_AFSEL = 0xff;
-
-    DBOP_TIMPOL_23 = 0x6000e;
-    DBOP_CTRL = 0x51008;
-    DBOP_TIMPOL_01 = 0x6e167;
-    DBOP_TIMPOL_23 = 0xa167e06f;
-
-    /* TODO: The OF calls some other functions here, but maybe not important */
-}
-
-
-static void lcd_write_cmd(int cmd)
-{
-    /* Write register */
-    DBOP_CTRL &= ~(1<<14);
-
-    DBOP_TIMPOL_23 = 0xa167006e;
-
-    DBOP_DOUT = cmd;
-
-    /* Wait for fifo to empty */
-    while ((DBOP_STAT & (1<<10)) == 0);
-
-    DBOP_TIMPOL_23 = 0xa167e06f;
-}
-
-void lcd_write_data(const fb_data* p_bytes, int count)
-{
-    while (count--)
-    {
-        DBOP_DOUT = *p_bytes++;
-
-        /* Wait for fifo to empty */
-        while ((DBOP_STAT & (1<<10)) == 0);
-    }
-}
-
-static void lcd_write_reg(int reg, int value)
-{
-    unsigned short data = value;
-
-    lcd_write_cmd(reg);
-    lcd_write_data(&data, 1);
-}
-
-/*** hardware configuration ***/
-
-void lcd_set_contrast(int val)
-{
-    (void)val;
-}
-
-void lcd_set_invert_display(bool yesno)
-{
-    (void)yesno;
-}
-
-static void flip_lcd(bool yesno)
-{
-    (void)yesno;
-}
-
-
-/* turn the display upside down (call lcd_update() afterwards) */
-void lcd_set_flip(bool yesno)
-{
-    display_flipped = yesno;
-    y_offset = yesno ? 4 : 0;   /* FIXME: Is a y_offset needed? */
-
-    if (display_on)
-        flip_lcd(yesno);
-}
-
-static void _display_on(void)
-{
-    /* Initialisation the display the same way as the original firmware */
-
-    lcd_write_reg(R_START_OSC, 0x0001); /* Start Oscilation */
-
-    lcd_write_reg(R_DRV_OUTPUT_CONTROL, 0x011b); /* 220 lines, GS=0, SS=1 */
-
-    /* B/C = 1: n-line inversion form
-     * EOR = 1: polarity inversion occurs by applying an EOR to odd/even
-     *          frame select signal and an n-line inversion signal.
-     * FLD = 01b: 1 field interlaced scan, external display iface */
-    lcd_write_reg(R_DRV_WAVEFORM_CONTROL, 0x0700);
-
-    /* Address counter updated in horizontal direction; left to right;
-     * vertical increment horizontal increment.
-     * data format for 8bit transfer or spi = 65k (5,6,5) */
-    lcd_write_reg(R_ENTRY_MODE, 0x0030);
-
-    /* Replace data on writing to GRAM */
-    lcd_write_reg(R_COMPARE_REG1, 0);
-    lcd_write_reg(R_COMPARE_REG2, 0);
-
-    lcd_write_reg(R_DISP_CONTROL1, 0x0000);  /* GON = 0, DTE = 0, D1-0 = 00b */
-
-    /* Front porch lines: 2; Back porch lines: 2; */
-    lcd_write_reg(R_DISP_CONTROL2, 0x0203);
-
-    /* Scan cycle = 0 frames */
-    lcd_write_reg(R_DISP_CONTROL3, 0x0000);
-
-    /* 16 clocks */
-    lcd_write_reg(R_FRAME_CYCLE_CONTROL, 0x0000);
-
-    /* 18-bit RGB interface (one transfer/pixel)
-     * internal clock operation;
-     * System interface/VSYNC interface */
-    lcd_write_reg(R_EXT_DISP_IF_CONTROL, 0x0000);
-
-
-    /* zero everything*/
-    lcd_write_reg(R_POWER_CONTROL1, 0x0000); /* STB = 0, SLP = 0 */
-
-    lcd_delay(10);
-
-    /* initialise power supply */
-
-    /* DC12-10 = 000b: Step-up1 = clock/8,
-     * DC02-00 = 000b: Step-up2 = clock/16,
-     * VC2-0   = 010b: VciOUT = 0.87 * VciLVL */
-    lcd_write_reg(R_POWER_CONTROL2, 0x0002); 
-
-    /* VRH3-0 = 1000b: Vreg1OUT = REGP * 1.90 */
-    lcd_write_reg(R_POWER_CONTROL3, 0x0008);
-
-    lcd_delay(40);
-    
-    lcd_write_reg(R_POWER_CONTROL4, 0x0000); /* VCOMG = 0 */
-
-    /* This register is unknown */
-    lcd_write_reg(0x56, 0x80f);
-
-
-    lcd_write_reg(R_POWER_CONTROL1, 0x4140);
-
-    lcd_delay(10);
-
-    lcd_write_reg(R_POWER_CONTROL2, 0x0000); 
-    lcd_write_reg(R_POWER_CONTROL3, 0x0013); 
-
-    lcd_delay(20);
-
-    lcd_write_reg(R_POWER_CONTROL4, 0x6d0e);
-
-    lcd_delay(20);
-
-    lcd_write_reg(R_POWER_CONTROL4, 0x6d0e);
-
-    lcd_write_reg(R_GAMMA_FINE_ADJ_POS1, 0x0002);
-    lcd_write_reg(R_GAMMA_FINE_ADJ_POS2, 0x0707);
-    lcd_write_reg(R_GAMMA_FINE_ADJ_POS3, 0x0182);
-    lcd_write_reg(R_GAMMA_GRAD_ADJ_POS, 0x0203);
-    lcd_write_reg(R_GAMMA_FINE_ADJ_NEG1, 0x0706);
-    lcd_write_reg(R_GAMMA_FINE_ADJ_NEG2, 0x0006);
-    lcd_write_reg(R_GAMMA_FINE_ADJ_NEG3, 0x0706);
-    lcd_write_reg(R_GAMMA_GRAD_ADJ_NEG, 0x0000);
-    lcd_write_reg(R_GAMMA_AMP_ADJ_RES_POS, 0x030f);
-    lcd_write_reg(R_GAMMA_AMP_AVG_ADJ_RES_NEG, 0x0f08);
-
-
-    lcd_write_reg(R_RAM_ADDR_SET, 0);
-    lcd_write_reg(R_GATE_SCAN_POS, 0);
-    lcd_write_reg(R_VERT_SCROLL_CONTROL, 0);
-    
-    lcd_write_reg(R_1ST_SCR_DRV_POS, (LCD_HEIGHT-1) << 8);
-    lcd_write_reg(R_2ND_SCR_DRV_POS, (LCD_HEIGHT-1) << 8);
-
-    lcd_write_reg(R_HORIZ_RAM_ADDR_POS, (LCD_WIDTH-1) << 8);
-    lcd_write_reg(R_VERT_RAM_ADDR_POS, (LCD_HEIGHT-1) << 8);
-
-
-    lcd_write_reg(R_DISP_CONTROL1, 0x0037);
-
-    display_on=true;  /* must be done before calling lcd_update() */
-    lcd_update();
-}
-
-/* LCD init */
-void lcd_init_device(void)
-{
-    ams3525_dbop_init();
-
-    /* Init GPIOs the same as the OF */
-
-    GPIOA_DIR |= (1<<5);
-    GPIOA_PIN(5) = 0;
-
-    GPIOA_PIN(3) = (1<<3);
-
-    GPIOA_DIR |= (3<<3);
-
-    GPIOA_PIN(3) = (1<<3);
-
-    GPIOA_PIN(4) = 0;  /*c80b0040 := 0;*/
-
-    GPIOA_DIR |= (1<<7);
-    GPIOA_PIN(7) = 0;
-
-    lcd_delay(1);
-
-    GPIOA_PIN(5) = (1<<5);
-
-    lcd_delay(1);
-
-    _display_on();
-}
-
-void lcd_enable(bool on)
-{
-    if(display_on!=on)
-    {
-        if(on)
-        {
-            _display_on();
-            lcd_activation_call_hook();
-        }
-        else
-        {
-            /* TODO: Implement off sequence */
-            display_on=false;
-        }
-    }
-}
-
-bool lcd_active(void)
-{
-    return display_on;
-}
-
-void lcd_sleep(void)
-{
-    /* TODO */
-}
-
-/*** update functions ***/
-
-/* Performance function to blit a YUV bitmap directly to the LCD
- * src_x, src_y, width and height should be even
- * x, y, width and height have to be within LCD bounds
- */
-void lcd_blit_yuv(unsigned char * const src[3],
-                  int src_x, int src_y, int stride,
-                  int x, int y, int width, int height)
-{
-    (void)src;
-    (void)src_x;
-    (void)src_y;
-    (void)stride;
-    (void)x;
-    (void)y;
-    (void)width;
-    (void)height;
-}
-
-/* Update the display.
-   This must be called after all other LCD functions that change the display. */
-void lcd_update(void)
-{
-    if (!display_on)
-        return;
-
-    lcd_write_reg(R_ENTRY_MODE, R_ENTRY_MODE_HORZ);
-
-    /* Set start position and window */
-    lcd_write_reg(R_HORIZ_RAM_ADDR_POS, (LCD_WIDTH-1) << 8);
-    lcd_write_reg(R_VERT_RAM_ADDR_POS, 
-                  ((y_offset + LCD_HEIGHT-1) << 8) | y_offset);
-    lcd_write_reg(R_RAM_ADDR_SET, (y_offset) << 8);
-
-    lcd_write_cmd(R_WRITE_DATA_2_GRAM);
-
-    lcd_write_data((unsigned short *)lcd_framebuffer, LCD_WIDTH*LCD_HEIGHT);
-    
-} /* lcd_update */
-
-
-/* Update a fraction of the display. */
-void lcd_update_rect(int x, int y, int width, int height)
-{
-    int ymax;
-    const unsigned short *ptr;
-
-    if (!display_on)
-        return;
-
-    if (x + width > LCD_WIDTH)
-        width = LCD_WIDTH - x; /* Clip right */
-    if (x < 0)
-        width += x, x = 0; /* Clip left */
-    if (width <= 0)
-        return; /* nothing left to do */
-
-    ymax = y + height;
-    if (ymax > LCD_HEIGHT)
-        ymax = LCD_HEIGHT; /* Clip bottom */
-    if (y < 0)
-        y = 0; /* Clip top */
-    if (y >= ymax)
-        return; /* nothing left to do */
-
-    lcd_write_reg(R_ENTRY_MODE, R_ENTRY_MODE_HORZ);
-    /* Set start position and window */
-    lcd_write_reg(R_HORIZ_RAM_ADDR_POS, 
-                  ((x + width-1) << 8) | x);
-    lcd_write_reg(R_VERT_RAM_ADDR_POS, 
-                  ((y_offset + y + height - 1) << 8) | (y_offset + y));
-    lcd_write_reg(R_RAM_ADDR_SET, ((y + y_offset) << 8) | x);
-
-    lcd_write_cmd(R_WRITE_DATA_2_GRAM);
-
-    ptr = (unsigned short *)&lcd_framebuffer[y][x];
-
-    do
-    {
-        lcd_write_data(ptr, width);
-        ptr += LCD_WIDTH;
-    }
-    while (++y < ymax);
-} /* lcd_update_rect */
diff --git a/firmware/target/arm/sandisk/sansa-c200/lcd-c200.c b/firmware/target/arm/lcd-c200_c200v2.c
index 69578455ac..b3e8f0eb4f 100644
--- a/firmware/target/arm/sandisk/sansa-c200/lcd-c200.c
+++ b/firmware/target/arm/lcd-c200_c200v2.c
@@ -24,6 +24,11 @@
 #include "kernel.h"
 #include "system.h"
 
+#ifdef SANSA_C200V2
+/* button driver needs to know if a lcd operation is in progress */
+static bool lcd_busy = false;
+#endif
+
 /* Display status */
 static unsigned lcd_yuv_options SHAREDBSS_ATTR = 0;
 static bool is_lcd_enabled = true;
@@ -65,7 +70,7 @@ static bool is_lcd_enabled = true;
 #define R_SCROLL_START_LINE    0x5a
 #define R_DATA_FORMAT_SELECT   0x60
 
-
+#if defined(SANSA_C200)
 /* wait for LCD */
 static inline void lcd_wait_write(void)
 {
@@ -73,23 +78,28 @@ static inline void lcd_wait_write(void)
 }
 
 /* send LCD data */
-static void lcd_send_data(unsigned data)
+static void lcd_send_data(const fb_data *data, int width)
 {
-    lcd_wait_write();
-    LCD1_DATA = data >> 8;
-    lcd_wait_write();
-    LCD1_DATA = data & 0xff;
+    while(width--)
+    {
+        lcd_wait_write();
+        LCD1_DATA = *data >> 8;
+        lcd_wait_write();
+        LCD1_DATA = *data++ & 0xff;
+    }
 }
 
 /* send LCD command */
-static void lcd_send_command(unsigned cmd)
+static void lcd_send_command(unsigned char cmd, unsigned char arg)
 {
     lcd_wait_write();
     LCD1_CMD = cmd;
+    /* if the argument is 0, we send a NOP (= 0) command */
+    lcd_wait_write();
+    LCD1_CMD = arg;
 }
 
-/* LCD init */
-void lcd_init_device(void)
+static inline void c200v1_lcd_init(void)
 {
     /* This is from the c200 of bootloader beginning at offset 0xbbf4 */
     outl(inl(0x70000010) & ~0xfc000000, 0x70000010);
@@ -97,7 +107,7 @@ void lcd_init_device(void)
 
     DEV_INIT2 &= ~0x400;
     udelay(10000);
-    
+
     LCD1_CONTROL &= ~0x4;
     udelay(15);
 
@@ -106,70 +116,138 @@ void lcd_init_device(void)
 
     LCD1_CONTROL = 0x0084; /* bits (9,10) = 00 -> fastest setting */
     udelay(10000);
+}
+
+#define lcd_delay(delay) udelay((delay) * 1000)
+
+#elif defined(SANSA_C200V2)
+
+static inline void lcd_delay(int delay)
+{   //TUNEME : delay is in milliseconds
+    delay <<= 14;
+    while(delay--) ;
+}
+
+/* send LCD data */
+static void lcd_send_data(const fb_data *data, int width)
+{
+    while(width--)
+    {
+        DBOP_DOUT = *data << 8 | *data >> 8;
+        data++;
+        while ((DBOP_STAT & (1<<10)) == 0);
+    }
+}
+
+/* send LCD command */
+static void lcd_send_command(unsigned char cmd, unsigned char val)
+{
+    DBOP_TIMPOL_23 = 0xa167006e;
+
+    DBOP_DOUT = cmd | val << 8;
+
+    while ((DBOP_STAT & (1<<10)) == 0);
+
+    DBOP_TIMPOL_23 = 0xa167e06f;
+}
+
+static inline void as3525_dbop_init(void)
+{
+    CGU_DBOP = (1<<3) | AS3525_DBOP_DIV;
+
+    DBOP_TIMPOL_01 = 0xe167e167;
+    DBOP_TIMPOL_23 = 0xe167006e;
+    DBOP_CTRL = 0x40008;
+
+    GPIOB_AFSEL = 0xc;
+    GPIOC_AFSEL = 0xff;
+
+    DBOP_TIMPOL_23 = 0x6006e;
+    DBOP_CTRL = 0x52008;
+    DBOP_TIMPOL_01 = 0x6e167;
+    DBOP_TIMPOL_23 = 0xa167e06f;
+
+    lcd_delay(20);
+}
 
-    lcd_send_command(R_STANDBY_OFF);
-    udelay(20000);
+/* we need to set the DBOP_DOUT pins high, for correct dbop reads */
+bool lcd_button_support(void)
+{
+    const fb_data data = 0xffff;
+
+    if (lcd_busy)       /* we can't use dbop for reading if we are in the */
+        return false;   /* middle of a write operation */
+
+    /* use out of screen coordinates */
+    lcd_send_command(R_X_ADDR_AREA, 0);
+    lcd_send_command(1, 0);
+    lcd_send_command(R_Y_ADDR_AREA, 0);
+    lcd_send_command(1, 0);
+
+    lcd_send_data(&data, 1);
+
+    return true;
+}
+#endif
+
+/* LCD init */
+void lcd_init_device(void)
+{
+#if defined(SANSA_C200)
+    c200v1_lcd_init();
+#elif defined(SANSA_C200V2)
+    as3525_dbop_init();
+#endif
+
+    lcd_send_command(R_STANDBY_OFF, 0);
+    lcd_delay(20);
+
+    lcd_send_command(R_OSCILLATION_MODE, 0x01);
+    lcd_delay(20);
 
-    lcd_send_command(R_OSCILLATION_MODE);
-    lcd_send_command(0x01);
-    udelay(20000);
+    lcd_send_command(R_DCDC_AMP_ONOFF, 0x01);
+    lcd_delay(20);
 
-    lcd_send_command(R_DCDC_AMP_ONOFF);
-    lcd_send_command(0x01);
-    udelay(20000);
+    lcd_send_command(R_DCDC_AMP_ONOFF, 0x09);
+    lcd_delay(20);
 
-    lcd_send_command(R_DCDC_AMP_ONOFF);
-    lcd_send_command(0x09);
-    udelay(20000);
+    lcd_send_command(R_DCDC_AMP_ONOFF, 0x0b);
+    lcd_delay(20);
 
-    lcd_send_command(R_DCDC_AMP_ONOFF);
-    lcd_send_command(0x0b);
-    udelay(20000);
+    lcd_send_command(R_DCDC_AMP_ONOFF, 0x0f);
+    lcd_delay(20);
 
-    lcd_send_command(R_DCDC_AMP_ONOFF);
-    lcd_send_command(0x0f);
-    udelay(20000);
+    lcd_send_command(R_DRIVER_OUTPUT_MODE, 0x07);
 
-    lcd_send_command(R_DRIVER_OUTPUT_MODE);
-    lcd_send_command(0x07);
+    lcd_send_command(R_DCDC_SET, 0x03);
 
-    lcd_send_command(R_DCDC_SET);
-    lcd_send_command(0x03);
+    lcd_send_command(R_DCDC_CLOCK_DIV, 0x03);
 
-    lcd_send_command(R_DCDC_CLOCK_DIV);
-    lcd_send_command(0x03);
+    lcd_send_command(R_TEMP_COMPENSATION, 0x01);
 
-    lcd_send_command(R_TEMP_COMPENSATION);
-    lcd_send_command(0x01);
+    lcd_send_command(R_CONTRAST_CONTROL1, 0x55);
 
-    lcd_send_command(R_CONTRAST_CONTROL1);
-    lcd_send_command(0x55);
+    lcd_send_command(R_ADDRESSING_MODE, 0x10);
 
-    lcd_send_command(R_ADDRESSING_MODE);
-    lcd_send_command(0x10);
+    lcd_send_command(R_ROW_VECTOR_MODE, 0x0e);
 
-    lcd_send_command(R_ROW_VECTOR_MODE);
-    lcd_send_command(0x0e);
+    lcd_send_command(R_N_LINE_INVERSION, 0x0d);
 
-    lcd_send_command(R_N_LINE_INVERSION);
-    lcd_send_command(0x0d);
+    lcd_send_command(R_FRAME_FREQ_CONTROL, 0);
 
-    lcd_send_command(R_FRAME_FREQ_CONTROL);
-    lcd_send_command(0);
+    lcd_send_command(R_ENTRY_MODE, 0x82);
 
-    lcd_send_command(R_ENTRY_MODE);
-    lcd_send_command(0x82);
+    /* vertical dimensions */
+    lcd_send_command(R_Y_ADDR_AREA, 0x1a);      /* y1 + 0x1a */
+    lcd_send_command(LCD_HEIGHT - 1 + 0x1a, 0); /* y2 + 0x1a */
 
-    lcd_send_command(R_Y_ADDR_AREA);         /* vertical dimensions */
-    lcd_send_command(0x1a);                  /* y1 + 0x1a */
-    lcd_send_command(LCD_HEIGHT - 1 + 0x1a); /* y2 + 0x1a */
+    /* horizontal dimensions */
+    lcd_send_command(R_X_ADDR_AREA, 0); /* x1 */
+    lcd_send_command(LCD_WIDTH - 1, 0); /* x2 */
 
-    lcd_send_command(R_X_ADDR_AREA);         /* horizontal dimensions */
-    lcd_send_command(0);                     /* x1 */
-    lcd_send_command(LCD_WIDTH - 1);         /* x2 */
-    udelay(100000);
+    lcd_delay(100);
 
-    lcd_send_command(R_DISPLAY_ON);
+    lcd_send_command(R_DISPLAY_ON, 0);
 }
 
 /*** hardware configuration ***/
@@ -180,8 +258,13 @@ int lcd_default_contrast(void)
 
 void lcd_set_contrast(int val)
 {
-    lcd_send_command(R_CONTRAST_CONTROL1);
-    lcd_send_command(val);
+#ifdef SANSA_C200V2
+    lcd_busy = true;
+#endif
+    lcd_send_command(R_CONTRAST_CONTROL1, val);
+#ifdef SANSA_C200V2
+    lcd_busy = false;
+#endif
 }
 
 void lcd_set_invert_display(bool yesno)
@@ -196,16 +279,22 @@ void lcd_enable(bool yesno)
     if (yesno == is_lcd_enabled)
         return;
 
+#ifdef SANSA_C200V2
+    lcd_busy = true;
+#endif
     if ((is_lcd_enabled = yesno))
     {
-        lcd_send_command(R_STANDBY_OFF);
-        lcd_send_command(R_DISPLAY_ON);
+        lcd_send_command(R_STANDBY_OFF, 0);
+        lcd_send_command(R_DISPLAY_ON, 0);
         lcd_activation_call_hook();
     }
     else
     {
-        lcd_send_command(R_STANDBY_ON);
+        lcd_send_command(R_STANDBY_ON, 0);
     }
+#ifdef SANSA_C200V2
+    lcd_busy = false;
+#endif
 }
 #endif
 
@@ -220,8 +309,13 @@ bool lcd_active(void)
 /* turn the display upside down (call lcd_update() afterwards) */
 void lcd_set_flip(bool yesno)
 {
-    lcd_send_command(R_DRIVER_OUTPUT_MODE);
-    lcd_send_command(yesno ? 0x02 : 0x07);
+#ifdef SANSA_C200V2
+    lcd_busy = true;
+#endif
+    lcd_send_command(R_DRIVER_OUTPUT_MODE, yesno ? 0x02 : 0x07);
+#ifdef SANSA_C200V2
+    lcd_busy = false;
+#endif
 }
 
 /*** update functions ***/
@@ -248,10 +342,14 @@ void lcd_blit_yuv(unsigned char * const src[3],
     unsigned char const * yuv_src[3];
     off_t z;
 
+#ifdef SANSA_C200V2
+    lcd_busy = true;
+#endif
+
     /* Sorry, but width and height must be >= 2 or else */
     width &= ~1;
     height >>= 1;
-    
+
     y += 0x1a;
 
     z = stride*src_y;
@@ -259,27 +357,21 @@ void lcd_blit_yuv(unsigned char * const src[3],
     yuv_src[1] = src[1] + (z >> 2) + (src_x >> 1);
     yuv_src[2] = src[2] + (yuv_src[1] - src[1]);
 
-    lcd_send_command(R_ENTRY_MODE);
-    lcd_send_command(0x80);
+    lcd_send_command(R_ENTRY_MODE, 0x80);
 
-    lcd_send_command(R_X_ADDR_AREA);
-    lcd_send_command(x);
-    lcd_send_command(x + width - 1);
+    lcd_send_command(R_X_ADDR_AREA, x);
+    lcd_send_command(x + width - 1, 0);
 
     if (lcd_yuv_options & LCD_YUV_DITHER)
     {
         do
         {
-            lcd_send_command(R_Y_ADDR_AREA);
-            lcd_send_command(y);
-            lcd_send_command(y + 1);
-
-            /* NOP needed because on some c200s, the previous lcd_send_command
-               is interpreted as a separate command instead of part of
-               R_Y_ADDR_AREA. */
-            lcd_send_command(R_NOP);
+            lcd_send_command(R_Y_ADDR_AREA, y);
+            lcd_send_command(y + 1, 0);
 
+#ifndef SANSA_C200V2 // TODO
             lcd_write_yuv420_lines_odither(yuv_src, width, stride, x, y);
+#endif
             yuv_src[0] += stride << 1; /* Skip down two luma lines */
             yuv_src[1] += stride >> 1; /* Skip down one chroma line */
             yuv_src[2] += stride >> 1;
@@ -291,13 +383,12 @@ void lcd_blit_yuv(unsigned char * const src[3],
     {
         do
         {
-            lcd_send_command(R_Y_ADDR_AREA);
-            lcd_send_command(y);
-            lcd_send_command(y + 1);
-
-            lcd_send_command(R_NOP);
+            lcd_send_command(R_Y_ADDR_AREA, y);
+            lcd_send_command(y + 1, 0);
 
+#ifndef SANSA_C200V2 // TODO
             lcd_write_yuv420_lines(yuv_src, width, stride);
+#endif
             yuv_src[0] += stride << 1; /* Skip down two luma lines */
             yuv_src[1] += stride >> 1; /* Skip down one chroma line */
             yuv_src[2] += stride >> 1;
@@ -305,6 +396,10 @@ void lcd_blit_yuv(unsigned char * const src[3],
         }
          while (--height > 0);
     }
+
+#ifdef SANSA_C200V2
+    lcd_busy = false;
+#endif
 }
 
 /* Update the display.
@@ -318,44 +413,43 @@ void lcd_update(void)
 void lcd_update_rect(int x, int y, int width, int height)
 {
     const fb_data *addr;
-    
+
     if (x + width >= LCD_WIDTH)
         width = LCD_WIDTH - x;
     if (y + height >= LCD_HEIGHT)
         height = LCD_HEIGHT - y;
-        
+
     if ((width <= 0) || (height <= 0))
         return; /* Nothing left to do. */
 
     addr = &lcd_framebuffer[y][x];
 
-    if (width <= 1) {                    
-        lcd_send_command(R_ENTRY_MODE);  /* The X end address must be larger */
-        lcd_send_command(0x80);          /* that the X start address, so we */
-        lcd_send_command(R_X_ADDR_AREA); /* switch to vertical mode for */
-        lcd_send_command(x);             /* single column updates and set */
-        lcd_send_command(x + 1);         /* the window width to 2 */
+#ifdef SANSA_C200V2
+    lcd_busy = true;
+#endif
+
+    if (width <= 1) {
+        /* The X end address must be larger than the X start address, so we
+         * switch to vertical mode for single column updates and set the
+         * window width to 2 */
+        lcd_send_command(R_ENTRY_MODE, 0x80);
+        lcd_send_command(R_X_ADDR_AREA, x);
+        lcd_send_command(x + 1, 0);
     } else {
-        lcd_send_command(R_ENTRY_MODE);
-        lcd_send_command(0x82);
-        lcd_send_command(R_X_ADDR_AREA);
-        lcd_send_command(x);
-        lcd_send_command(x + width - 1);
+        lcd_send_command(R_ENTRY_MODE, 0x82);
+        lcd_send_command(R_X_ADDR_AREA, x);
+        lcd_send_command(x + width - 1, 0);
     }
 
-    lcd_send_command(R_Y_ADDR_AREA);
-    lcd_send_command(y + 0x1a);
-    lcd_send_command(y + height - 1 + 0x1a);
-
-    /* NOP needed because on some c200s, the previous lcd_send_command is
-       interpreted as a separate command instead of part of R_Y_ADDR_AREA. */
-    lcd_send_command(R_NOP);
+    lcd_send_command(R_Y_ADDR_AREA, y + 0x1a);
+    lcd_send_command(y + height - 1 + 0x1a, 0);
 
     do {
-        int w = width;
-        do {
-            lcd_send_data(*addr++);
-        } while (--w > 0);
-        addr += LCD_WIDTH - width;
+        lcd_send_data(addr, width);
+        addr += LCD_WIDTH;
     } while (--height > 0);
+
+#ifdef SANSA_C200V2
+    lcd_busy = false;
+#endif
 }