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/* Copyright 2019 The Chromium OS Authors. All rights reserved.
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "common.h"
#include "console.h"
#include "i2c.h"
#include "i2c_bitbang.h"
#include "test_util.h"
#include "util.h"
const struct i2c_port_t i2c_bitbang_ports[] = {
{"", 0, 100, GPIO_I2C_SCL, GPIO_I2C_SDA}
};
const unsigned int i2c_bitbang_ports_used = 1;
struct pin_state {
int scl, sda;
} history[64];
int history_count;
void reset_state(void)
{
history[0] = (struct pin_state) {1, 1};
history_count = 1;
bitbang_set_started(0);
}
void gpio_set_level(enum gpio_signal signal, int level)
{
struct pin_state new = history[history_count - 1];
/* reject if stack is full */
if (history_count >= ARRAY_SIZE(history))
return;
if (signal == GPIO_I2C_SDA)
new.sda = level;
else if (signal == GPIO_I2C_SCL)
new.scl = level;
if (new.scl != history[history_count - 1].scl ||
new.sda != history[history_count - 1].sda)
history[history_count++] = new;
}
int gpio_get_level(enum gpio_signal signal)
{
if (signal == GPIO_I2C_SDA)
return history[history_count - 1].sda;
else if (signal == GPIO_I2C_SCL)
return history[history_count - 1].scl;
return 0;
}
static int test_i2c_start_stop(void)
{
struct pin_state expected[] = {
/* start */
{1, 1},
{1, 0},
{0, 0},
/* stop */
{1, 0},
{1, 1},
};
int i;
reset_state();
bitbang_start_cond(&i2c_bitbang_ports[0]);
bitbang_stop_cond(&i2c_bitbang_ports[0]);
TEST_EQ((int)ARRAY_SIZE(expected), history_count, "%d");
for (i = 0; i < ARRAY_SIZE(expected); i++) {
TEST_EQ(expected[i].scl, history[i].scl, "%d");
TEST_EQ(expected[i].sda, history[i].sda, "%d");
}
return EC_SUCCESS;
}
static int test_i2c_repeated_start(void)
{
struct pin_state expected[] = {
/* start */
{1, 1},
{1, 0},
{0, 0},
/* repeated start */
{0, 1},
{1, 1},
{1, 0},
{0, 0},
};
int i;
reset_state();
bitbang_start_cond(&i2c_bitbang_ports[0]);
bitbang_start_cond(&i2c_bitbang_ports[0]);
TEST_EQ((int)ARRAY_SIZE(expected), history_count, "%d");
for (i = 0; i < ARRAY_SIZE(expected); i++) {
TEST_EQ(expected[i].scl, history[i].scl, "%d");
TEST_EQ(expected[i].sda, history[i].sda, "%d");
}
return EC_SUCCESS;
}
static int test_i2c_write(void)
{
struct pin_state expected[] = {
/* start */
{1, 1},
{1, 0},
{0, 0},
/* bit 7: 0 */
{1, 0},
{0, 0},
/* bit 6: 1 */
{0, 1},
{1, 1},
{0, 1},
/* bit 5: 0 */
{0, 0},
{1, 0},
{0, 0},
/* bit 4: 1 */
{0, 1},
{1, 1},
{0, 1},
/* bit 3: 0 */
{0, 0},
{1, 0},
{0, 0},
/* bit 2: 1 */
{0, 1},
{1, 1},
{0, 1},
/* bit 1: 1 */
{1, 1},
{0, 1},
/* bit 0: 0 */
{0, 0},
{1, 0},
{0, 0},
/* read bit */
{0, 1},
{1, 1},
{0, 1},
/* stop */
{0, 0},
{1, 0},
{1, 1},
};
int i, ret;
reset_state();
bitbang_start_cond(&i2c_bitbang_ports[0]);
ret = bitbang_write_byte(&i2c_bitbang_ports[0], 0x56);
/* expected to fail because no slave answering the nack bit */
TEST_EQ(EC_ERROR_BUSY, ret, "%d");
TEST_EQ((int)ARRAY_SIZE(expected), history_count, "%d");
for (i = 0; i < ARRAY_SIZE(expected); i++) {
TEST_EQ(expected[i].scl, history[i].scl, "%d");
TEST_EQ(expected[i].sda, history[i].sda, "%d");
}
return EC_SUCCESS;
}
void run_test(int argc, char **argv)
{
test_reset();
RUN_TEST(test_i2c_start_stop);
RUN_TEST(test_i2c_repeated_start);
RUN_TEST(test_i2c_write);
test_print_result();
}
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