1/* $NetBSD: motoi2creg.h,v 1.1 2011/01/04 01:25:17 matt Exp $ */
2
3/*-
4 * Copyright (c) 2007, 2010 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Matt Thomas.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef _DEV_I2C_MOTOI2CREG_H_
33#define _DEV_I2C_MOTOI2CREG_H_
34
35/*
36 * This I2C controller is a common design used on many Motorola/Freescale
37 * chip like the i.MX/MC9328, MPC8548, etc.  Different names in bit field
38 * definition and not suffered from document error.
39 */
40#define I2CADR	0x0000	/* my own I2C addr to respond for an external master */
41#define I2CFDR	0x0004	/* frequency devider */
42#define I2CCR	0x0008	/* control */
43#define	 CR_MEN   0x80	/* enable this HW */
44#define	 CR_MIEN  0x40	/* enable interrupt */
45#define	 CR_MSTA  0x20	/* 0->1 activates START, 1->0 makes STOP condition */
46#define	 CR_MTX   0x10	/* 1 for Tx, 0 for Rx */
47#define	 CR_TXAK  0x08	/* 1 makes no acknowledge when Rx */
48#define	 CR_RSTA  0x04	/* generate repeated START condition */
49#define I2CSR	0x000c	/* status */
50#define	 SR_MCF   0x80	/* 0 means transfer in progress, 1 when completed */
51#define	 SR_MAAS  0x40	/* 1 means addressed as slave */
52#define	 SR_MBB   0x20	/* 1 before STOP condition is detected */
53#define	 SR_MAL   0x10	/* arbitration was lost */
54#define	 SR_MIF   0x02	/* indicates data transter completion */
55#define	 SR_RXAK  0x01	/* 1 to indicate receive has completed */
56#define I2CDR	0x0010	/* data */
57#define	I2CDFSRR 0x0014	/* digital filter sampling rate register */
58
59/*
60 * The equation to calculate the divider frequency (from AN2919) is:
61 *
62 * Frequency divider = B * (A + (floor(3 * C / B) * 2))
63 *
64 * where (in little endian bit order, msb to lsb) FDR is split into 2 3-bit
65 * fields: fA contains bits 5,1,0 and fB contains bits 4,3,2.
66 *
67 * A is used as an index into { 9, 10, 12, 15, 5, 6, 7, 8 } though
68 * on faster machines these are doubled to { 18, 20, 24, 50, 10, 12, 14, 16 }.
69 * B is either 2**(b + 1) or 2**(b + 4).
70 *
71 * C is the sampling rate, which may be settable via I2CDFSRR register though
72 * not all implementations have it.  Regardless, we just leave it at its
73 * default setting (16).  So floor(3 * C / B) * 2 becomes a precomputable
74 * quantity.  Once we know its value for fB=0, we can simply shift it right
75 * as fB increases since B is a power-of-2.
76 */
77
78#define FDR_A(n)		(((n) & 0x20) >> 3) | ((n) & 3))
79#define FDR_B(n)		(((n) & 0x1c) >> 2)
80
81#define	MOTOI2C_GROUP_A_VALUES	0x8765fca9U
82#define	MOTOI2C_A(a)		((MOTOI2C_GROUP_A_VALUE >> (4*(fdr_a))) & 0xf)
83#define	MOTOI2C_B(b)		(1 + (fdr_b))
84#define	MOTOI2C_DIV(name, fdr)	\
85	((name##_A(FDR_A(hdr)) + named##_C(FDR_B(fdr))) << name##_B(FDR_B(hdr)))
86
87#define	IMX31_A(fdr_a)		MOTOI2C_A(fdr_a)
88#define	IMX31_B(fdr_b)		MOTOI2C_B(fdr_b)
89#define IMX31_C(fdr_b)		(6 >> (fdr_b))
90#define	IMX31_DIV(fdr)		MOTOI2C_DIV(IMX31, fdr)
91
92#define	MCF52259_A(fdr_a)	MOTOI2C_A(fdr_a)
93#define	MCF52259_B(fdr_b)	MOTOI2C_B(fdr_b)
94#define MCF52259_C(fdr_b)	(5 >> (fdr_b))
95#define	MCF52259_DIV(fdr)	MOTOI2C_DIV(MCF52259, fdr)
96
97#define	MPC85xx_A(fdr_a)	(MOTOI2C_A(fdr_a) << 1)
98#define	MPC85xx_B(fdr_b)	(4 + (fdr_b))
99#define	MPC85xx_C(fdr_b)	((6 >> (fdr_b)) & ~1)
100#define	MPC85xx_DIV(fdr)	MOTOI2C_DIV(MPC85xx, fdr)
101
102#endif /* !_DEV_I2C_MOTOI2CREG_H_ */
103