Clip+: boot to OF if USB is connected

To be sure that there is no mistake in this code, it is run *after*
the known to work HOME & LEFT buttons checks, unlike other Sansas

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@26122 a1c6a512-1295-4272-9138-f99709370657

firmware/export/config/sansaclipplus.h

@@ -177,7 +177,7 @@
 #define CONFIG_USBOTG USBOTG_AS3525
 
 /* enable these for the experimental usb stack */
-//#define HAVE_USBSTACK
+#define HAVE_USBSTACK
 #define USB_VENDOR_ID 0x0781
 #define USB_PRODUCT_ID 0x74d1
 #endif /* BOOTLOADER */

rbutil/mkamsboot/README

@@ -61,8 +61,7 @@ firmware and the new (rockbox) firmware.
 
   The player will boot into the Original Firmware as well if it is powered up by
 inserting an usb cable.
-  ***Note : on the m200v4 and Clip+, powering up by usb will cause booting into
+  ***Note : on the m200v4 powering up by usb will cause booting into the new firmware.
-the new firmware.
 
 Hacking
 -------

rbutil/mkamsboot/dualboot.c

@@ -126,21 +126,31 @@ unsigned char dualboot_clipv2[280] = {
     0x00, 0x20, 0xa0, 0xe3, 0x15, 0xff, 0x2f, 0xe1, 0x3c, 0x00, 0x00, 0x00, 0x14, 0x00, 0x0f, 0xc8,
     0x00, 0x00, 0x0b, 0xc8, 0x00, 0x00, 0x0e, 0xc8
 };
-unsigned char dualboot_clipplus[216] = {
+unsigned char dualboot_clipplus[372] = {
-    0xc0, 0xf0, 0x9f, 0xe5, 0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea,
+    0x54, 0xf1, 0x9f, 0xe5, 0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea,
     0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x24, 0x00, 0x1f, 0xe5,
     0x24, 0x10, 0x1f, 0xe5, 0x01, 0x20, 0x40, 0xe0, 0x18, 0x30, 0x1f, 0xe5, 0x01, 0x40, 0x50, 0xe4,
     0x01, 0x40, 0x43, 0xe4, 0x00, 0x00, 0x52, 0xe1, 0xfb, 0xff, 0xff, 0x1a, 0x2c, 0x30, 0x0f, 0xe5,
-    0x64, 0x00, 0x9f, 0xe5, 0x00, 0x10, 0x90, 0xe5, 0x01, 0x18, 0x81, 0xe3, 0x00, 0x10, 0x80, 0xe5,
+    0xf8, 0x00, 0x9f, 0xe5, 0x00, 0x10, 0x90, 0xe5, 0x01, 0x18, 0x81, 0xe3, 0x00, 0x10, 0x80, 0xe5,
-    0x58, 0x00, 0x9f, 0xe5, 0x20, 0x10, 0x90, 0xe5, 0x54, 0x00, 0x9f, 0xe5, 0x08, 0x20, 0x90, 0xe5,
+    0xec, 0x00, 0x9f, 0xe5, 0x20, 0x10, 0x90, 0xe5, 0xe8, 0x00, 0x9f, 0xe5, 0x08, 0x20, 0x90, 0xe5,
-    0x01, 0x20, 0x82, 0xe1, 0x00, 0x00, 0x52, 0xe3, 0x02, 0x00, 0x00, 0x1a, 0x64, 0x00, 0x1f, 0xe5,
+    0x01, 0x20, 0x82, 0xe1, 0x00, 0x00, 0x52, 0xe3, 0x27, 0x00, 0x00, 0x1a, 0xd8, 0x00, 0x9f, 0xe5,
-    0x64, 0x10, 0x1f, 0xe5, 0x01, 0x00, 0x00, 0xea, 0x78, 0x00, 0x1f, 0xe5, 0x78, 0x10, 0x1f, 0xe5,
+    0x00, 0x10, 0xa0, 0xe3, 0x00, 0x10, 0x80, 0xe5, 0xc0, 0x00, 0x9f, 0xe5, 0x00, 0x10, 0x90, 0xe5,
-    0x70, 0x30, 0x1f, 0xe5, 0x02, 0x50, 0x83, 0xe2, 0x01, 0x40, 0x43, 0xe0, 0x01, 0x20, 0x50, 0xe4,
+    0x02, 0x18, 0x81, 0xe3, 0x7f, 0x10, 0xc1, 0xe3, 0x00, 0x10, 0x80, 0xe5, 0xbc, 0x00, 0x9f, 0xe5,
-    0x01, 0x20, 0x43, 0xe4, 0x04, 0x00, 0x53, 0xe1, 0xfb, 0xff, 0xff, 0x1a, 0x01, 0x00, 0x83, 0xe2,
+    0x00, 0x10, 0xa0, 0xe3, 0x24, 0x10, 0x80, 0xe5, 0x3c, 0x10, 0xa0, 0xe3, 0x1c, 0x10, 0x80, 0xe5,
-    0x00, 0x20, 0xa0, 0xe3, 0x15, 0xff, 0x2f, 0xe1, 0x3c, 0x00, 0x00, 0x00, 0x14, 0x00, 0x0f, 0xc8,
+    0x00, 0x10, 0xa0, 0xe3, 0x20, 0x10, 0x80, 0xe5, 0x8c, 0x10, 0xa0, 0xe3, 0x04, 0x10, 0x80, 0xe5,
-    0x00, 0x00, 0x0d, 0xc8, 0x00, 0x00, 0x0b, 0xc8
+    0x51, 0x20, 0xa0, 0xe3, 0x0c, 0x20, 0x80, 0xe5, 0x30, 0x10, 0x90, 0xe5, 0x01, 0x00, 0x11, 0xe3,
+    0xfc, 0xff, 0xff, 0x1a, 0x02, 0x17, 0xa0, 0xe3, 0x01, 0x10, 0x51, 0xe2, 0xfd, 0xff, 0xff, 0x1a,
+    0x25, 0x10, 0xa0, 0xe3, 0x44, 0x10, 0x80, 0xe5, 0x02, 0x20, 0x82, 0xe3, 0x0c, 0x20, 0x80, 0xe5,
+    0x01, 0x10, 0xa0, 0xe3, 0x10, 0x10, 0x80, 0xe5, 0x10, 0x10, 0x90, 0xe5, 0x00, 0x00, 0x51, 0xe3,
+    0xfc, 0xff, 0xff, 0x1a, 0x00, 0x10, 0x90, 0xe5, 0x08, 0x00, 0x11, 0xe3, 0x02, 0x00, 0x00, 0x1a,
+    0xf8, 0x00, 0x1f, 0xe5, 0xf8, 0x10, 0x1f, 0xe5, 0x01, 0x00, 0x00, 0xea, 0x0c, 0x01, 0x1f, 0xe5,
+    0x0c, 0x11, 0x1f, 0xe5, 0x04, 0x31, 0x1f, 0xe5, 0x02, 0x50, 0x83, 0xe2, 0x01, 0x40, 0x43, 0xe0,
+    0x01, 0x20, 0x50, 0xe4, 0x01, 0x20, 0x43, 0xe4, 0x04, 0x00, 0x53, 0xe1, 0xfb, 0xff, 0xff, 0x1a,
+    0x01, 0x00, 0x83, 0xe2, 0x00, 0x20, 0xa0, 0xe3, 0x15, 0xff, 0x2f, 0xe1, 0x3c, 0x00, 0x00, 0x00,
+    0x14, 0x00, 0x0f, 0xc8, 0x00, 0x00, 0x0d, 0xc8, 0x00, 0x00, 0x0b, 0xc8, 0x10, 0x00, 0x0f, 0xc8,
+    0x00, 0x00, 0x07, 0xc8
 };
 unsigned char dualboot_fuzev2[236] = {
     0xd4, 0xf0, 0x9f, 0xe5, 0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea, 0xfe, 0xff, 0xff, 0xea,

rbutil/mkamsboot/dualboot.h

@@ -7,5 +7,5 @@ extern unsigned char dualboot_c200v2[336];
 extern unsigned char dualboot_m200v4[212];
 extern unsigned char dualboot_fuze[236];
 extern unsigned char dualboot_clipv2[280];
-extern unsigned char dualboot_clipplus[216];
+extern unsigned char dualboot_clipplus[372];
 extern unsigned char dualboot_fuzev2[236];

rbutil/mkamsboot/dualboot/dualboot.S

@@ -26,6 +26,7 @@
 .set GPIOB,     0xC80C0000
 .set GPIOC,     0xC80D0000
 .set GPIOD,     0xC80E0000
+.set CGU_PROC,  0xC80F0010
 .set CGU_PERI,  0xC80F0014
 .set I2C_BASE,  0xC8070000
 .set I2C_DATA,  0x00
@@ -239,6 +240,68 @@ uclcopy:
 
         cmp     r2, #0              @ test input from pins
         bne     boot_of             @ branch directly to OF if either pin high
+
+
+        @ check USB connection
+
+        ldr     r0, =CGU_PROC
+        mov     r1, #0
+        str     r1, [r0]    @ fclk = 24MHz
+
+        ldr     r0, =CGU_PERI
+        ldr     r1, [r0]
+        /* enable i2c audio master clock */
+        orr     r1, r1, #(1<<17)
+        /* pclk = fclk = 24MHz */
+        bic     r1, r1, #0x7f
+        str     r1, [r0]
+
+        ldr     r0, =I2C_BASE
+        /* disable i2c interrupts */
+        mov     r1, #0
+        str     r1, [r0, #I2C_IMR]
+        /* setup prescaler */
+        mov     r1, #I2C_PRESCALER_LOW
+        str     r1, [r0, #I2C_CPSR0]
+        mov     r1, #I2C_PRESCALER_HIGH
+        str     r1, [r0, #I2C_CPSR1]
+        /* setup i2c slave address */
+        mov     r1, #(AS3514_I2C_ADDR << 1)
+        str     r1, [r0, #I2C_SLAD0]
+        mov     r2, #0x51
+        str     r2, [r0, #I2C_CNTRL]
+
+        /* wait for not busy */
+1:
+        ldr     r1, [r0, #I2C_SR]
+        tst     r1, #1
+        bne 1b
+
+        /* wait a bit (~100ms) else detection fails */
+        mov     r1, #0x80000
+1:      subs    r1, r1, #1
+        bne 1b
+
+        /* start read of irq_enrd0 */
+        mov     r1, #AS3514_IRQ_ENRD0
+        str     r1, [r0, #I2C_SADDR]
+        orr     r2, r2, #(1 << 1)
+        str     r2, [r0, #I2C_CNTRL]
+        mov     r1, #1
+        str     r1, [r0, #I2C_DACNT]
+
+        /* wait for transfer to finish */
+1:
+        ldr     r1, [r0, #I2C_DACNT]
+        cmp     r1, #0
+        bne     1b
+
+        /* load result and test USB_STATUS bit */
+        ldr     r1, [r0, #I2C_DATA]
+        tst     r1, #(1 << 3)
+        bne     boot_of
+
+
 #elif defined(SANSA_C200V2)
         /* check for RIGHT on C6, should changed to LEFT as soon as it
          * known in which pin that is in order for consistency  */