From e63f92f586bb50ef52da5c4771ba865ba5afb751 Mon Sep 17 00:00:00 2001
From: Alan Cox <alan@linux.intel.com>
Date: Sat, 28 Mar 2015 23:24:12 +0000
Subject: [PATCH] px4,7508: expand the 7508 code a bit further

Still much to do including things like the keyboard decoding. Also not
clear what we should do with a lot of the events.
---
 Kernel/platform-px4plus/7508.h    | 10 ++++
 Kernel/platform-px4plus/cpu7508.s | 89 +++++++++++++++++++++++++++++--
 2 files changed, 96 insertions(+), 3 deletions(-)
 create mode 100644 Kernel/platform-px4plus/7508.h

diff --git a/Kernel/platform-px4plus/7508.h b/Kernel/platform-px4plus/7508.h
new file mode 100644
index 00000000..eb21ca6c
--- /dev/null
+++ b/Kernel/platform-px4plus/7508.h
@@ -0,0 +1,10 @@
+#ifndef _7508_H
+#define _7508_H
+
+extern void c7508_power_off(void);
+extern void c7508_interrupt(void);
+extern void c7508_msg(uint8_t *buf);
+
+extern uint8_t rtc_clock;		/* Rolling 1 second timer */
+
+#endif
\ No newline at end of file
diff --git a/Kernel/platform-px4plus/cpu7508.s b/Kernel/platform-px4plus/cpu7508.s
index 92abf6f2..267ab6ae 100644
--- a/Kernel/platform-px4plus/cpu7508.s
+++ b/Kernel/platform-px4plus/cpu7508.s
@@ -5,6 +5,13 @@
 
 		.area _CODE
 
+
+		.globl _c7508_msg
+		.globl c7508_power_off
+		.globl c7508_interrupt
+
+		.globl _rtc_clock
+
 c7508_cmdbyte:
 		; Wait for the 7508 to go ready
 		in a, (0x05)
@@ -18,13 +25,21 @@ c7508_cmdbyte:
 		out (0x01), a
 		ret
 
-c7508_waitrsp:
+;
+;	Wait for a byte of response from the 7508 and return it in D.
+;
+c7508_replybyte:
 		in a, (0x05)
 		and 4
 		jr z, c7508_waitrsp
+		in a, (0x06)
+		ld d, a
+		ld a, #2
+		out (0x01), a
 		ret
 
-c7508_int:	; The 7508 wants us to ask it for status
+c7508_interrupt:
+		; The 7508 wants us to ask it for status
 		ld c, #0x02
 		call c7508_cmdbyte
 		call c7508_waitrsp
@@ -61,9 +76,77 @@ c7508_1sec:
 		pop af
 		ret
 
+;
+;	Keyboard event - punt out to C
+;
 c7508_keyin:
-		; FIXME
+		ld l, a
+		ld h, #0
+		push af
+		call _key_pressed
+		pop af
 		ret
 
+;
+;	Turn off the 7508 as an interrupt source
+;
+c7508_irqoff:
+		ld a, #0x0a
+		out (4), a
+		ret
+
+;
+;	Turn on the 7508 as an interrupt source
+;
+c7508_irqon:
+		ld a, #0x0b
+		out (4), a
+		ret
+;
+;	Send a command. HL points to the start of the command B holds the
+;	number of bytes to send, the reply will be placed in the memory
+;	following the command and E bytes are expected
+;
+c7508_docmd:
+		call c7508_irqoff
+		ld c, (hl)
+		inc hl
+		call c7508_cmdbyte
+		djnz c7508_docmd
+		ld b, e
+		xor a
+		cp b
+		jp z, c7508_irqon
+c7508_doreply:
+		call c7508_replybyte
+		ld (hl), d
+		djnz c7508_doreply
+		call c7508_irqon
+		ret
+
+_c7508_power_off:
+		ld c, #1
+		call c7508_cmdbyte		; won't return !
+		di
+		hlt
+
+;
+;	General purpose C interface to 7508 commands. Pass a buffer that
+;	holds the length to send, length to receive, send data, space for
+;	receive data.
+;
+_c7508_msg:
+		pop bc
+		pop de
+		pop hl			; Parameter
+		push hl
+		push de
+		push bc
+		ld b, (hl)
+		inc hl
+		ld e,(hl)
+		inc hl
+		jr c7508_docmd
+
 		.area _DATA
 _rtc_clock:	.db 0
-- 
2.34.1