/* * Maxim MAX1110/1111 ADC chip emulation. * * Copyright (c) 2006 Openedhand Ltd. * Written by Andrzej Zaborowski <balrog@zabor.org> * * This code is licensed under the GNU GPLv2. */#include "hw.h"#include "i2c.h"struct max111x_s {    qemu_irq interrupt;    uint8_t tb1, rb2, rb3;    int cycle;    int input[8];    int inputs, com;};/* Control-byte bitfields */#define CB_PD0		(1 << 0)#define CB_PD1		(1 << 1)#define CB_SGL		(1 << 2)#define CB_UNI		(1 << 3)#define CB_SEL0		(1 << 4)#define CB_SEL1		(1 << 5)#define CB_SEL2		(1 << 6)#define CB_START	(1 << 7)#define CHANNEL_NUM(v, b0, b1, b2)	\			((((v) >> (2 + (b0))) & 4) |	\			 (((v) >> (3 + (b1))) & 2) |	\			 (((v) >> (4 + (b2))) & 1))uint32_t max111x_read(void *opaque){    struct max111x_s *s = (struct max111x_s *) opaque;    if (!s->tb1)        return 0;    switch (s->cycle ++) {    case 1:        return s->rb2;    case 2:        return s->rb3;    }    return 0;}/* Interpret a control-byte */void max111x_write(void *opaque, uint32_t value){    struct max111x_s *s = (struct max111x_s *) opaque;    int measure, chan;    /* Ignore the value if START bit is zero */    if (!(value & CB_START))        return;    s->cycle = 0;    if (!(value & CB_PD1)) {        s->tb1 = 0;        return;    }    s->tb1 = value;    if (s->inputs == 8)        chan = CHANNEL_NUM(value, 1, 0, 2);    else        chan = CHANNEL_NUM(value & ~CB_SEL0, 0, 1, 2);    if (value & CB_SGL)        measure = s->input[chan] - s->com;    else        measure = s->input[chan] - s->input[chan ^ 1];    if (!(value & CB_UNI))        measure ^= 0x80;    s->rb2 = (measure >> 2) & 0x3f;    s->rb3 = (measure << 6) & 0xc0;    if (s->interrupt)        qemu_irq_raise(s->interrupt);}static void max111x_save(QEMUFile *f, void *opaque){    struct max111x_s *s = (struct max111x_s *) opaque;    int i;    qemu_put_8s(f, &s->tb1);    qemu_put_8s(f, &s->rb2);    qemu_put_8s(f, &s->rb3);    qemu_put_be32(f, s->inputs);    qemu_put_be32(f, s->com);    for (i = 0; i < s->inputs; i ++)        qemu_put_byte(f, s->input[i]);}static int max111x_load(QEMUFile *f, void *opaque, int version_id){    struct max111x_s *s = (struct max111x_s *) opaque;    int i;    qemu_get_8s(f, &s->tb1);    qemu_get_8s(f, &s->rb2);    qemu_get_8s(f, &s->rb3);    if (s->inputs != qemu_get_be32(f))        return -EINVAL;    s->com = qemu_get_be32(f);    for (i = 0; i < s->inputs; i ++)        s->input[i] = qemu_get_byte(f);    return 0;}static int max111x_iid = 0;static struct max111x_s *max111x_init(qemu_irq cb){    struct max111x_s *s;    s = (struct max111x_s *)            qemu_mallocz(sizeof(struct max111x_s));    memset(s, 0, sizeof(struct max111x_s));    s->interrupt = cb;    /* TODO: add a user interface for setting these */    s->input[0] = 0xf0;    s->input[1] = 0xe0;    s->input[2] = 0xd0;    s->input[3] = 0xc0;    s->input[4] = 0xb0;    s->input[5] = 0xa0;    s->input[6] = 0x90;    s->input[7] = 0x80;    s->com = 0;    register_savevm("max111x", max111x_iid ++, 0,                    max111x_save, max111x_load, s);    return s;}struct max111x_s *max1110_init(qemu_irq cb){    struct max111x_s *s = max111x_init(cb);    s->inputs = 8;    return s;}struct max111x_s *max1111_init(qemu_irq cb){    struct max111x_s *s = max111x_init(cb);    s->inputs = 4;    return s;}void max111x_set_input(struct max111x_s *s, int line, uint8_t value){    if (line >= s->inputs) {        printf("%s: There's no input %i\n", __FUNCTION__, line);        return;    }    s->input[line] = value;}