Add support for scroll wheel to Sansa button driver. Should be replaced with an interrupt based driver to improve responsiveness (once we figure out how).

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@11772 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Barry Wardell 2006-12-16 00:21:41 +00:00
parent eb56c8a8d1
commit 331e34bfd4

View file

@ -28,11 +28,17 @@
#include "backlight.h"
#include "system.h"
static unsigned int old_wheel_value = 0;
static unsigned int wheel_repeat = BUTTON_NONE;
void button_init_device(void)
{
/* Enable all buttons except the wheel */
/* Enable all buttons */
GPIOF_ENABLE |= 0xff;
GPIOH_ENABLE |= 0xc0;
/* Read initial wheel value (bit 6-7 of GPIOH) */
old_wheel_value = GPIOH_INPUT_VAL & 0xc0;
}
bool button_hold(void)
@ -49,6 +55,7 @@ int button_read_device(void)
unsigned char state;
static bool hold_button = false;
bool hold_button_old;
unsigned int new_wheel_value;
/* Hold */
hold_button_old = hold_button;
@ -76,6 +83,59 @@ int button_read_device(void)
if ((state & 0x10) == 0) btn |= BUTTON_SELECT; /* The centre button */
if ((state & 0x20) == 0) btn |= BUTTON_UP; /* The "play" button */
if ((state & 0x40) != 0) btn |= BUTTON_POWER;
/* Read wheel
* Bits 6 and 7 of GPIOH change as follows:
* Clockwise rotation 01 -> 00 -> 10 -> 11
* Counter-clockwise 11 -> 10 -> 00 -> 01
*
* This is equivalent to wheel_value of:
* Clockwise rotation 0x40 -> 0x00 -> 0x80 -> 0xc0
* Counter-clockwise 0xc0 -> 0x80 -> 0x00 -> 0x40
*/
new_wheel_value = GPIOH_INPUT_VAL & 0xc0;
switch(new_wheel_value){
case 0x00:
if(old_wheel_value==0x80)
btn |= BUTTON_SCROLL_UP;
else if (old_wheel_value==0x40)
btn |= BUTTON_SCROLL_DOWN;
break;
case 0x40:
if(old_wheel_value==0x00)
btn |= BUTTON_SCROLL_UP;
else if (old_wheel_value==0xc0)
btn |= BUTTON_SCROLL_DOWN;
break;
case 0x80:
if(old_wheel_value==0xc0)
btn |= BUTTON_SCROLL_UP;
else if (old_wheel_value==0x00)
btn |= BUTTON_SCROLL_DOWN;
break;
case 0xc0:
if(old_wheel_value==0x40)
btn |= BUTTON_SCROLL_UP;
else if (old_wheel_value==0x80)
btn |= BUTTON_SCROLL_DOWN;
break;
}
if(wheel_repeat == BUTTON_NONE){
if(btn & BUTTON_SCROLL_UP)
wheel_repeat = BUTTON_SCROLL_UP;
if(btn & BUTTON_SCROLL_DOWN)
wheel_repeat = BUTTON_SCROLL_DOWN;
} else if (wheel_repeat == BUTTON_SCROLL_UP) {
btn |= BUTTON_SCROLL_UP;
wheel_repeat = BUTTON_NONE;
} else if (wheel_repeat == BUTTON_SCROLL_DOWN) {
btn |= BUTTON_SCROLL_DOWN;
wheel_repeat = BUTTON_NONE;
}
old_wheel_value = new_wheel_value;
}
return btn;