Sansa Clip: simplify matrix key scan

Merge clipv1/clipv2 code since they use the same 3x3 matrix
clipzip keyscan buttons now work in bootloader
clipplus untouched (no matrix)

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@31235 a1c6a512-1295-4272-9138-f99709370657

3 files changed, 82 insertions, 286 deletions

diff --git a/firmware/target/arm/as3525/sansa-clipv2/button-clip.c b/firmware/target/arm/as3525/button-clip.c
index 1356bfbc55..b6679ca359 100644
--- a/firmware/target/arm/as3525/sansa-clipv2/button-clip.c
+++ b/firmware/target/arm/as3525/button-clip.c
@@ -27,14 +27,37 @@
 #include "backlight.h"
 #endif
 
+#if   defined(SANSA_CLIP)
+# define OUT_PIN GPIOC_PIN
+# define OUT_DIR GPIOC_DIR
+# define OUT_INITIAL 0
+# define IN_PIN  GPIOB_PIN
+# define IN_DIR  GPIOB_DIR
+#elif defined(SANSA_CLIPV2)
+# define OUT_PIN GPIOD_PIN
+# define OUT_DIR GPIOD_DIR
+# define OUT_INITIAL 1
+# define IN_PIN  GPIOD_PIN
+# define IN_DIR  GPIOD_DIR
+#endif
+
+static const int rows[3] = {
+#if   defined(SANSA_CLIP)
+    4, 5, 6
+#elif defined(SANSA_CLIPV2)
+    5, 6, 4
+#endif
+};
+
 void button_init_device(void)
 {
     GPIOA_DIR &= ~((1<<7) | (1<<3));
-    GPIOD_DIR &= ~((1<<2) | (1<<1) | (1<<0));
-    GPIOD_PIN(3) = 1<<3;
-    GPIOD_PIN(4) = 1<<4;
-    GPIOD_PIN(5) = 1<<5;
-    GPIOD_DIR |= ((1<<5) | (1<<4) | (1<<3));
+    IN_DIR &= ~((1<<2) | (1<<1) | (1<<0));
+
+    for (int i = 0; i < 3; i++) {
+        OUT_PIN(rows[i]) = OUT_INITIAL << rows[i];
+        OUT_DIR |= 1 << rows[i];
+    }
 
     /* get initial readings */
     button_read_device();
@@ -44,9 +67,8 @@ void button_init_device(void)
 
 int button_read_device(void)
 {
-    static int row = 0;
-    static int buttons = 0;
-    static unsigned power_counter = 0;
+    static int row, buttons;
+    static unsigned power_counter;
 
     if(button_hold())
     {
@@ -66,84 +88,47 @@ int button_read_device(void)
     else
         buttons &= ~BUTTON_POWER;
 
-    /* This is a keypad using D3-D5 as columns and D0-D2 as rows */
-    switch (row) {
-
-    case 0:
-        buttons &= ~(BUTTON_VOL_UP | BUTTON_UP);
-
-        (void)GPIOD_PIN(0); /* D3D0 is unused */
-
-        if (!GPIOD_PIN(1))
-            buttons |= BUTTON_VOL_UP;
-
-        if (!GPIOD_PIN(2))
-            buttons |= BUTTON_UP;
-
-        GPIOD_PIN(3) = 1<<3;
-        GPIOD_PIN(4) = 0x00;
-        row++;
-        break;
-
-    case 1:
-        buttons &= ~(BUTTON_LEFT | BUTTON_SELECT | BUTTON_RIGHT);
-
-        if (!GPIOD_PIN(0))
-            buttons |= BUTTON_LEFT;
-
-        if (!GPIOD_PIN(1))
-            buttons |= BUTTON_SELECT;
+    static const int matrix [3][3] = {
+        { 0 /*unused*/, BUTTON_VOL_UP,   BUTTON_UP },
+        { BUTTON_LEFT,  BUTTON_SELECT,   BUTTON_RIGHT },
+        { BUTTON_DOWN,  BUTTON_VOL_DOWN, BUTTON_HOME },
+    };
 
-        if (!GPIOD_PIN(2))
-            buttons |= BUTTON_RIGHT;
+    for (int i = 0; i<3; i++)
+        if (IN_PIN(i))
+            buttons |=  matrix[row][i];
+        else
+            buttons &= ~matrix[row][i];
 
-        GPIOD_PIN(4) = 1<<4;
-        GPIOD_PIN(5) = 0x00;
-        row++;
-        break;
-
-    case 2:
-        buttons &= ~(BUTTON_DOWN | BUTTON_VOL_DOWN | BUTTON_HOME);
-
-        if (!GPIOD_PIN(0))
-            buttons |= BUTTON_DOWN;
-
-        if (!GPIOD_PIN(1))
-            buttons |= BUTTON_VOL_DOWN;
-
-        if (!GPIOD_PIN(2))
-            buttons |= BUTTON_HOME;
-
-        GPIOD_PIN(5) = 1<<5;
-        GPIOD_PIN(3) = 0x00;
-
-    default:
-        row = 0;
-        break;
-    }
+    /* prepare next row */
+    OUT_PIN(rows[row]) = 0 << rows[row];
+    row++;
+    row %= 3;
+    OUT_PIN(rows[row]) = 1 << rows[row];
 
     return buttons;
 }
 
 bool button_hold(void)
 {
-#ifndef BOOTLOADER
-    static bool hold_button_old = false;
-#endif
-
+#ifdef SANSA_CLIPV2
     GPIOA_DIR |= 1<<7;
     GPIOA_PIN(7) = 1<<7;
 
     int delay = 50;
     while(delay--)
         asm("nop");
+#endif
 
     bool hold_button = (GPIOA_PIN(3) != 0);
 
+#ifdef SANSA_CLIPV2
     GPIOA_PIN(7) = 0;
     GPIOA_DIR &= ~(1<<7);
+#endif
 
 #ifndef BOOTLOADER
+    static bool hold_button_old = false;
     /* light handling */
     if (hold_button != hold_button_old)
     {
diff --git a/firmware/target/arm/as3525/sansa-clip/button-clip.c b/firmware/target/arm/as3525/sansa-clip/button-clip.c
deleted file mode 100644
index a64fddb564..0000000000
--- a/firmware/target/arm/as3525/sansa-clip/button-clip.c
+++ /dev/null
@@ -1,156 +0,0 @@
-/***************************************************************************
- *             __________               __   ___.
- *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
- *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
- *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
- *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
- *                     \/            \/     \/    \/            \/
- * $Id$
- *
- * Copyright (C) 2009 Bertrik Sikken
- * Copyright (C) 2008 François Dinel
- * Copyright (C) 2008 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 "system.h"
-#include "button-target.h"
-#include "as3525.h"
-#ifndef BOOTLOADER /* backlight on hold handling */
-#include "backlight.h"
-#endif
-
-/*  The Sansa Clip uses a button matrix that is scanned by selecting one of
-    three rows and reading back the button states from the columns.
-
-    In this driver, the row is changed at each call (i.e. once per tick).
-    In one tick, column data from one row is read back and then the next row
-    is selected for the following tick. This mechanism ensures that there is
-    plenty time between selecting a row and reading the columns, avoiding the
-    need for explicit delays.
-*/
-
-
-void button_init_device(void)
-{
-    GPIOA_DIR &= ~((1<<7) | (1<<3));
-    GPIOB_DIR &= ~((1<<2) | (1<<1) | (1<<0));
-    GPIOC_PIN(4) = 0;
-    GPIOC_PIN(5) = 0;
-    GPIOC_PIN(6) = 0;
-    GPIOC_DIR |= ((1<<6) | (1<<5) | (1<<4));
-    
-    /* get initial readings */
-    button_read_device();
-    button_read_device();
-    button_read_device();
-}
-
-int button_read_device(void)
-{
-    static int row = 0;
-    static int buttons = 0;
-    static unsigned power_counter = 0;
-
-    if(button_hold())
-    {
-        power_counter = HZ;
-        return 0;
-    }
-
-    /* direct GPIO connections */
-    /* read power, but not if hold button was just released, since
-     * you basically always hit power due to the slider mechanism after
-     * releasing hold (wait 1 sec) */
-    if (power_counter)
-        power_counter--;
-
-    if (GPIOA_PIN(7) && !power_counter)
-        buttons |= BUTTON_POWER;
-    else
-        buttons &= ~BUTTON_POWER;
-
-    /* This is a keypad using C4-C6 as columns and B0-B2 as rows */
-    switch (row) {
-
-    case 0:
-        buttons &= ~(BUTTON_VOL_UP | BUTTON_UP);
-
-        (void)GPIOB_PIN(0); /* C4B0 is unused */
-
-        if (GPIOB_PIN(1))
-            buttons |= BUTTON_VOL_UP;
-
-        if (GPIOB_PIN(2))
-            buttons |= BUTTON_UP;
-
-        GPIOC_PIN(4) = 0;
-        GPIOC_PIN(5) = (1<<5);
-        row++;
-        break;
-
-    case 1:
-        buttons &= ~(BUTTON_LEFT | BUTTON_SELECT | BUTTON_RIGHT);
-
-        if (GPIOB_PIN(0))
-            buttons |= BUTTON_LEFT;
-
-        if (GPIOB_PIN(1))
-            buttons |= BUTTON_SELECT;
-
-        if (GPIOB_PIN(2))
-            buttons |= BUTTON_RIGHT;
-
-        GPIOC_PIN(5) = 0;
-        GPIOC_PIN(6) = (1<<6);
-        row++;
-        break;
-
-    case 2:
-        buttons &= ~(BUTTON_DOWN | BUTTON_VOL_DOWN | BUTTON_HOME);
-
-        if (GPIOB_PIN(0))
-            buttons |= BUTTON_DOWN;
-
-        if (GPIOB_PIN(1))
-            buttons |= BUTTON_VOL_DOWN;
-
-        if (GPIOB_PIN(2))
-            buttons |= BUTTON_HOME;
-
-        GPIOC_PIN(6) = 0;
-        GPIOC_PIN(4) = (1<<4);
-
-    default:
-        row = 0;
-        break;
-    }
-
-    return buttons;
-}
-
-bool button_hold(void)
-{
-    bool hold_button = (GPIOA_PIN(3) != 0);
-
-#ifndef BOOTLOADER
-    /* backlight handling */
-
-    static bool hold_button_old = false;
-
-    if (hold_button != hold_button_old)
-    {
-        hold_button_old = hold_button;
-        backlight_hold_changed(hold_button);
-    }
-#endif /* BOOTLOADER */
-
-    return hold_button;
-}
diff --git a/firmware/target/arm/as3525/sansa-clipzip/button-clipzip.c b/firmware/target/arm/as3525/sansa-clipzip/button-clipzip.c
index 40b20cdce3..c22c5e24e9 100644
--- a/firmware/target/arm/as3525/sansa-clipzip/button-clipzip.c
+++ b/firmware/target/arm/as3525/sansa-clipzip/button-clipzip.c
@@ -21,97 +21,64 @@
  ****************************************************************************/
 
 #include "config.h"
-
 #include "button-target.h"
 #include "as3525v2.h"
+#include "system.h"
 #include "kernel.h"
-#include "system-target.h"
 
 static int keyscan(void)
 {
-    static int buttons = 0;
-    static int row = 1;
+    static int buttons, row;
+    static const int matrix[2][3] = {
+        { BUTTON_RIGHT, BUTTON_SELECT, BUTTON_UP },
+        { BUTTON_HOME,  BUTTON_DOWN,   BUTTON_LEFT },
+    };
+
+    for (int i = 0; i < 3; i++)
+        if (GPIOC_PIN(3 + i))
+            buttons |=  matrix[row][i];
+        else
+            buttons &= ~matrix[row][i];
 
-    switch (row) {
-    
-    case 1:
-        /* read row 1 */
-        buttons &= ~(BUTTON_RIGHT | BUTTON_SELECT | BUTTON_UP);
-        if (GPIOC_PIN(3)) {
-            buttons |= BUTTON_RIGHT;
-        }
-        if (GPIOC_PIN(4)) {
-            buttons |= BUTTON_SELECT;
-        }
-        if (GPIOC_PIN(5)) {
-            buttons |= BUTTON_UP;
-        }
-        
-        /* prepare row 2 */
-        GPIOC_PIN(1) = 0;
-        GPIOC_PIN(2) = (1 << 2);
-        row = 2;
-        break;
-        
-    case 2:
-        /* read row 2 */
-        buttons &= ~(BUTTON_HOME | BUTTON_DOWN | BUTTON_LEFT);
-        if (GPIOC_PIN(3)) {
-            buttons |= BUTTON_HOME;
-        }
-        if (GPIOC_PIN(4)) {
-            buttons |= BUTTON_DOWN;
-        }
-        if (GPIOC_PIN(5)) {
-            buttons |= BUTTON_LEFT;
-        }
-    
-        /* prepare row 1 */
-        GPIOC_PIN(1) = (1 << 1);
-        GPIOC_PIN(2) = 0;
-        row = 1;
-        break;
+    /* prepare next row */
+    GPIOC_PIN(1) = row << 1;
+    row ^= 1;
+    GPIOC_PIN(2) = row << 2;
+
+    /* delay a bit if interrupts are disabled, to be sure next row will read */
+    if (!irq_enabled())
+        for (volatile int i = 0; i < 0x500; i++) ;
 
-    default:
-        row = 1;
-        break;
-    }
-    
     return buttons;
 }
 
 void button_init_device(void)
 {
     /* GPIO A6, A7 and D6 are direct button inputs */
-    GPIOA_DIR &= ~(1 << 6);
-    GPIOA_DIR &= ~(1 << 7);
+    GPIOA_DIR &= ~(1 << 6 | 1<< 7);
     GPIOD_DIR &= ~(1 << 6);
-    
+
     /* GPIO C1, C2, C3, C4, C5 are used in a column/row key scan matrix */
     GPIOC_DIR |= ((1 << 1) | (1 << 2));
     GPIOC_DIR &= ~((1 << 3) | (1 << 4) | (1 << 5));
+
+    /* initial reading */
+    button_read_device();
+    sleep(1);
+    button_read_device();
+    sleep(1);
 }
 
 int button_read_device(void)
 {
     int buttons = 0;
 
-    /* power */
-    if (GPIOD_PIN(6)) {
+    if (GPIOD_PIN(6))
         buttons |= BUTTON_POWER;
-    }
-
-    /* volume */
-    if (GPIOA_PIN(6)) {
+    if (GPIOA_PIN(6))
         buttons |= BUTTON_VOL_DOWN;
-    }
-    if (GPIOA_PIN(7)) {
+    if (GPIOA_PIN(7))
         buttons |= BUTTON_VOL_UP;
-    }
-    
-    /* keyscan buttons */
-    buttons |= keyscan();
 
-    return buttons;
+    return buttons | keyscan();
 }
-