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|
/* Copyright 2013 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.
*/
/* I2C cross-platform code for Chrome EC */
#include "battery.h"
#include "clock.h"
#include "charge_state.h"
#include "console.h"
#include "host_command.h"
#include "gpio.h"
#include "i2c.h"
#include "system.h"
#include "task.h"
#include "usb_pd_tcpm.h"
#include "util.h"
#include "watchdog.h"
#include "virtual_battery.h"
/* Delay for bitbanging i2c corresponds roughly to 100kHz. */
#define I2C_BITBANG_DELAY_US 5
/* Number of attempts to unwedge each pin. */
#define UNWEDGE_SCL_ATTEMPTS 10
#define UNWEDGE_SDA_ATTEMPTS 3
#define CPUTS(outstr) cputs(CC_I2C, outstr)
#define CPRINTS(format, args...) cprints(CC_I2C, format, ## args)
#define CPRINTF(format, args...) cprintf(CC_I2C, format, ## args)
/* Only chips with multi-port controllers will define I2C_CONTROLLER_COUNT */
#ifndef I2C_CONTROLLER_COUNT
#define I2C_CONTROLLER_COUNT I2C_PORT_COUNT
#endif
static struct mutex port_mutex[I2C_CONTROLLER_COUNT];
/* A bitmap of the controllers which are currently servicing a request. */
static uint32_t i2c_port_active_list;
BUILD_ASSERT(I2C_CONTROLLER_COUNT < 32);
static uint8_t port_protected[I2C_PORT_COUNT];
/**
* Non-deterministically test the lock status of the port. If another task
* has locked the port and the caller is accessing it illegally, then this test
* will incorrectly return true. However, callers which failed to statically
* lock the port will fail quickly.
*/
static int i2c_port_is_locked(int port)
{
#ifdef CONFIG_I2C_MULTI_PORT_CONTROLLER
/* Test the controller, not the port */
port = i2c_port_to_controller(port);
#endif
/* can't lock a non-existing port */
if (port < 0)
return 0;
return (i2c_port_active_list >> port) & 1;
}
const struct i2c_port_t *get_i2c_port(const int port)
{
int i;
/* Find the matching port in i2c_ports[] table. */
for (i = 0; i < i2c_ports_used; i++) {
if (i2c_ports[i].port == port)
return &i2c_ports[i];
}
return NULL;
}
static int chip_i2c_xfer_with_notify(const int port,
const uint16_t slave_addr_flags,
const uint8_t *out, int out_size,
uint8_t *in, int in_size, int flags)
{
int ret;
if (IS_ENABLED(CONFIG_I2C_DEBUG))
i2c_trace_notify(port, slave_addr_flags, 0, out, out_size);
if (IS_ENABLED(CONFIG_I2C_XFER_BOARD_CALLBACK))
i2c_start_xfer_notify(port, slave_addr_flags);
ret = chip_i2c_xfer(port, slave_addr_flags,
out, out_size, in, in_size, flags);
if (IS_ENABLED(CONFIG_I2C_XFER_BOARD_CALLBACK))
i2c_end_xfer_notify(port, slave_addr_flags);
if (IS_ENABLED(CONFIG_I2C_DEBUG))
i2c_trace_notify(port, slave_addr_flags, 1, in, in_size);
return ret;
}
#ifdef CONFIG_I2C_XFER_LARGE_READ
/*
* Internal function that splits reading into multiple chip_i2c_xfer() calls
* if in_size exceeds CONFIG_I2C_CHIP_MAX_READ_SIZE.
*/
static int i2c_xfer_no_retry(const int port,
const uint16_t slave_addr_flags,
const uint8_t *out, int out_size,
uint8_t *in, int in_size, int flags)
{
int ret;
int out_flags = flags & I2C_XFER_START;
int in_chunk_size = MIN(in_size, CONFIG_I2C_CHIP_MAX_READ_SIZE);
in_size -= in_chunk_size;
out_flags |= !in_size ? (flags & I2C_XFER_STOP) : 0;
ret = chip_i2c_xfer_with_notify(port, slave_addr_flags,
out, out_size, in,
in_chunk_size, out_flags);
in += in_chunk_size;
while (in_size && ret == EC_SUCCESS) {
in_chunk_size = MIN(in_size, CONFIG_I2C_CHIP_MAX_READ_SIZE);
in_size -= in_chunk_size;
ret = chip_i2c_xfer_with_notify(port, slave_addr_flags,
NULL, 0, in,
in_chunk_size, !in_size ? (flags & I2C_XFER_STOP) : 0);
in += in_chunk_size;
}
return ret;
}
#endif /* CONFIG_I2C_XFER_LARGE_READ */
int i2c_xfer_unlocked(const int port,
const uint16_t slave_addr_flags,
const uint8_t *out, int out_size,
uint8_t *in, int in_size, int flags)
{
int i;
int ret = EC_SUCCESS;
if (!i2c_port_is_locked(port)) {
CPUTS("Access I2C without lock!");
return EC_ERROR_INVAL;
}
for (i = 0; i <= CONFIG_I2C_NACK_RETRY_COUNT; i++) {
#ifdef CONFIG_I2C_XFER_LARGE_READ
ret = i2c_xfer_no_retry(port, slave_addr_flags,
out, out_size, in,
in_size, flags);
#else
ret = chip_i2c_xfer_with_notify(port, slave_addr_flags,
out, out_size,
in, in_size, flags);
#endif /* CONFIG_I2C_XFER_LARGE_READ */
if (ret != EC_ERROR_BUSY)
break;
}
return ret;
}
int i2c_xfer(const int port,
const uint16_t slave_addr_flags,
const uint8_t *out, int out_size,
uint8_t *in, int in_size)
{
int rv;
i2c_lock(port, 1);
rv = i2c_xfer_unlocked(port, slave_addr_flags,
out, out_size, in, in_size,
I2C_XFER_SINGLE);
i2c_lock(port, 0);
return rv;
}
void i2c_lock(int port, int lock)
{
#ifdef CONFIG_I2C_MULTI_PORT_CONTROLLER
/* Lock the controller, not the port */
port = i2c_port_to_controller(port);
#endif
if (port < 0)
return;
if (lock) {
mutex_lock(port_mutex + port);
/* Disable interrupt during changing counter for preemption. */
interrupt_disable();
i2c_port_active_list |= 1 << port;
/* Ec cannot enter sleep if there's any i2c port active. */
disable_sleep(SLEEP_MASK_I2C_MASTER);
interrupt_enable();
} else {
interrupt_disable();
i2c_port_active_list &= ~BIT(port);
/* Once there is no i2c port active, enable sleep bit of i2c. */
if (!i2c_port_active_list)
enable_sleep(SLEEP_MASK_I2C_MASTER);
interrupt_enable();
mutex_unlock(port_mutex + port);
}
}
void i2c_prepare_sysjump(void)
{
int i;
/* Lock all i2c controllers */
for (i = 0; i < I2C_CONTROLLER_COUNT; ++i)
mutex_lock(port_mutex + i);
}
int i2c_read32(const int port,
const uint16_t slave_addr_flags,
int offset, int *data)
{
int rv;
uint8_t reg, buf[sizeof(uint32_t)];
reg = offset & 0xff;
/* I2C read 32-bit word: transmit 8-bit offset, and read 32bits */
rv = i2c_xfer(port, slave_addr_flags,
®, 1, buf, sizeof(uint32_t));
if (rv)
return rv;
if (I2C_IS_BIG_ENDIAN(slave_addr_flags))
*data = ((int)buf[0] << 24) | ((int)buf[1] << 16) |
((int)buf[0] << 8) | buf[1];
else
*data = ((int)buf[3] << 24) | ((int)buf[2] << 16) |
((int)buf[1] << 8) | buf[0];
return EC_SUCCESS;
}
int i2c_write32(const int port,
const uint16_t slave_addr_flags,
int offset, int data)
{
uint8_t buf[1 + sizeof(uint32_t)];
buf[0] = offset & 0xff;
if (I2C_IS_BIG_ENDIAN(slave_addr_flags)) {
buf[1] = (data >> 24) & 0xff;
buf[2] = (data >> 16) & 0xff;
buf[3] = (data >> 8) & 0xff;
buf[4] = data & 0xff;
} else {
buf[1] = data & 0xff;
buf[2] = (data >> 8) & 0xff;
buf[3] = (data >> 16) & 0xff;
buf[4] = (data >> 24) & 0xff;
}
return i2c_xfer(port, slave_addr_flags,
buf, sizeof(uint32_t) + 1, NULL, 0);
}
int i2c_read16(const int port,
const uint16_t slave_addr_flags,
int offset, int *data)
{
int rv;
uint8_t reg, buf[sizeof(uint16_t)];
reg = offset & 0xff;
/* I2C read 16-bit word: transmit 8-bit offset, and read 16bits */
rv = i2c_xfer(port, slave_addr_flags,
®, 1, buf, sizeof(uint16_t));
if (rv)
return rv;
if (I2C_IS_BIG_ENDIAN(slave_addr_flags))
*data = ((int)buf[0] << 8) | buf[1];
else
*data = ((int)buf[1] << 8) | buf[0];
return EC_SUCCESS;
}
int i2c_write16(const int port,
const uint16_t slave_addr_flags,
int offset, int data)
{
uint8_t buf[1 + sizeof(uint16_t)];
buf[0] = offset & 0xff;
if (I2C_IS_BIG_ENDIAN(slave_addr_flags)) {
buf[1] = (data >> 8) & 0xff;
buf[2] = data & 0xff;
} else {
buf[1] = data & 0xff;
buf[2] = (data >> 8) & 0xff;
}
return i2c_xfer(port, slave_addr_flags,
buf, 1 + sizeof(uint16_t), NULL, 0);
}
int i2c_read8(const int port,
const uint16_t slave_addr_flags,
int offset, int *data)
{
int rv;
uint8_t reg = offset;
uint8_t buf;
reg = offset;
rv = i2c_xfer(port, slave_addr_flags, ®, 1, &buf, 1);
if (!rv)
*data = buf;
return rv;
}
int i2c_write8(const int port,
const uint16_t slave_addr_flags,
int offset, int data)
{
uint8_t buf[2];
buf[0] = offset;
buf[1] = data;
return i2c_xfer(port, slave_addr_flags, buf, 2, 0, 0);
}
int i2c_read_offset16(const int port,
const uint16_t slave_addr_flags,
uint16_t offset, int *data, int len)
{
int rv;
uint8_t buf[sizeof(uint16_t)], addr[sizeof(uint16_t)];
if (len < 0 || len > 2)
return EC_ERROR_INVAL;
addr[0] = (offset >> 8) & 0xff;
addr[1] = offset & 0xff;
/* I2C read 16-bit word: transmit 16-bit offset, and read buffer */
rv = i2c_xfer(port, slave_addr_flags, addr, 2, buf, len);
if (rv)
return rv;
if (len == 1) {
*data = buf[0];
} else {
if (I2C_IS_BIG_ENDIAN(slave_addr_flags))
*data = ((int)buf[0] << 8) | buf[1];
else
*data = ((int)buf[1] << 8) | buf[0];
}
return EC_SUCCESS;
}
int i2c_write_offset16(const int port,
const uint16_t slave_addr_flags,
uint16_t offset, int data, int len)
{
uint8_t buf[2 + sizeof(uint16_t)];
if (len < 0 || len > 2)
return EC_ERROR_INVAL;
buf[0] = (offset >> 8) & 0xff;
buf[1] = offset & 0xff;
if (len == 1) {
buf[2] = data & 0xff;
} else {
if (I2C_IS_BIG_ENDIAN(slave_addr_flags)) {
buf[2] = (data >> 8) & 0xff;
buf[3] = data & 0xff;
} else {
buf[2] = data & 0xff;
buf[3] = (data >> 8) & 0xff;
}
}
return i2c_xfer(port, slave_addr_flags, buf, 2 + len, NULL, 0);
}
int i2c_read_offset16_block(const int port,
const uint16_t slave_addr_flags,
uint16_t offset, uint8_t *data, int len)
{
uint8_t addr[sizeof(uint16_t)];
addr[0] = (offset >> 8) & 0xff;
addr[1] = offset & 0xff;
return i2c_xfer(port, slave_addr_flags, addr, 2, data, len);
}
int i2c_write_offset16_block(const int port,
const uint16_t slave_addr_flags,
uint16_t offset, const uint8_t *data, int len)
{
int rv;
uint8_t addr[sizeof(uint16_t)];
addr[0] = (offset >> 8) & 0xff;
addr[1] = offset & 0xff;
/*
* Split into two transactions to avoid the stack space consumption of
* appending the destination address with the data array.
*/
i2c_lock(port, 1);
rv = i2c_xfer_unlocked(port, slave_addr_flags, addr, 2, NULL, 0,
I2C_XFER_START);
if (!rv)
rv = i2c_xfer_unlocked(port, slave_addr_flags,
data, len, NULL, 0, I2C_XFER_STOP);
i2c_lock(port, 0);
return rv;
}
int i2c_read_string(const int port,
const uint16_t slave_addr_flags,
int offset, uint8_t *data, int len)
{
int rv;
uint8_t reg, block_length;
i2c_lock(port, 1);
reg = offset;
/*
* Send device reg space offset, and read back block length. Keep this
* session open without a stop.
*/
rv = i2c_xfer_unlocked(port, slave_addr_flags,
®, 1, &block_length, 1, I2C_XFER_START);
if (rv)
goto exit;
if (len && block_length > (len - 1))
block_length = len - 1;
rv = i2c_xfer_unlocked(port, slave_addr_flags,
0, 0, data, block_length, I2C_XFER_STOP);
data[block_length] = 0;
exit:
i2c_lock(port, 0);
return rv;
}
int i2c_read_block(const int port,
const uint16_t slave_addr_flags,
int offset, uint8_t *data, int len)
{
int rv;
uint8_t reg_address = offset;
rv = i2c_xfer(port, slave_addr_flags, ®_address, 1, data, len);
return rv;
}
int i2c_write_block(const int port,
const uint16_t slave_addr_flags,
int offset, const uint8_t *data, int len)
{
int rv;
uint8_t reg_address = offset;
/*
* Split into two transactions to avoid the stack space consumption of
* appending the destination address with the data array.
*/
i2c_lock(port, 1);
rv = i2c_xfer_unlocked(port, slave_addr_flags,
®_address, 1, NULL, 0, I2C_XFER_START);
if (!rv) {
rv = i2c_xfer_unlocked(port, slave_addr_flags,
data, len, NULL, 0, I2C_XFER_STOP);
}
i2c_lock(port, 0);
return rv;
}
int get_sda_from_i2c_port(int port, enum gpio_signal *sda)
{
const struct i2c_port_t *i2c_port = get_i2c_port(port);
/* Crash if the port given is not in the i2c_ports[] table. */
ASSERT(i2c_port);
/* Check if the SCL and SDA pins have been defined for this port. */
if (i2c_port->scl == 0 && i2c_port->sda == 0)
return EC_ERROR_INVAL;
*sda = i2c_port->sda;
return EC_SUCCESS;
}
int get_scl_from_i2c_port(int port, enum gpio_signal *scl)
{
const struct i2c_port_t *i2c_port = get_i2c_port(port);
/* Crash if the port given is not in the i2c_ports[] table. */
ASSERT(i2c_port);
/* Check if the SCL and SDA pins have been defined for this port. */
if (i2c_port->scl == 0 && i2c_port->sda == 0)
return EC_ERROR_INVAL;
*scl = i2c_port->scl;
return EC_SUCCESS;
}
void i2c_raw_set_scl(int port, int level)
{
enum gpio_signal g;
if (get_scl_from_i2c_port(port, &g) == EC_SUCCESS)
gpio_set_level(g, level);
}
void i2c_raw_set_sda(int port, int level)
{
enum gpio_signal g;
if (get_sda_from_i2c_port(port, &g) == EC_SUCCESS)
gpio_set_level(g, level);
}
int i2c_raw_mode(int port, int enable)
{
enum gpio_signal sda, scl;
int ret_sda, ret_scl;
/* Get the SDA and SCL pins for this port. If none, then return. */
if (get_sda_from_i2c_port(port, &sda) != EC_SUCCESS)
return EC_ERROR_INVAL;
if (get_scl_from_i2c_port(port, &scl) != EC_SUCCESS)
return EC_ERROR_INVAL;
if (enable) {
int raw_gpio_mode_flags = GPIO_ODR_HIGH;
/* If the CLK line is 1.8V, then ensure we set 1.8V mode */
if ((gpio_list + scl)->flags & GPIO_SEL_1P8V)
raw_gpio_mode_flags |= GPIO_SEL_1P8V;
/*
* To enable raw mode, take out of alternate function mode and
* set the flags to open drain output.
*/
ret_sda = gpio_config_pin(MODULE_I2C, sda, 0);
ret_scl = gpio_config_pin(MODULE_I2C, scl, 0);
gpio_set_flags(scl, raw_gpio_mode_flags);
gpio_set_flags(sda, raw_gpio_mode_flags);
} else {
/*
* Configure the I2C pins to exit raw mode and return
* to normal mode.
*/
ret_sda = gpio_config_pin(MODULE_I2C, sda, 1);
ret_scl = gpio_config_pin(MODULE_I2C, scl, 1);
}
return ret_sda == EC_SUCCESS ? ret_scl : ret_sda;
}
/*
* Unwedge the i2c bus for the given port.
*
* Some devices on our i2c busses keep power even if we get a reset. That
* means that they could be part way through a transaction and could be
* driving the bus in a way that makes it hard for us to talk on the bus.
* ...or they might listen to the next transaction and interpret it in a
* weird way.
*
* Note that devices could be in one of several states:
* - If a device got interrupted in a write transaction it will be watching
* for additional data to finish its write. It will probably be looking to
* ack the data (drive the data line low) after it gets everything.
* - If a device got interrupted while responding to a register read, it will
* be watching for clocks and will drive data out when it sees clocks. At
* the moment it might be trying to send out a 1 (so both clock and data
* may be high) or it might be trying to send out a 0 (so it's driving data
* low).
*
* We attempt to unwedge the bus by doing:
* - If SCL is being held low, then a slave is clock extending. The only
* thing we can do is try to wait until the slave stops clock extending.
* - Otherwise, we will toggle the clock until the slave releases the SDA line.
* Once the SDA line is released, try to send a STOP bit. Rinse and repeat
* until either the bus is normal, or we run out of attempts.
*
* Note this should work for most devices, but depending on the slaves i2c
* state machine, it may not be possible to unwedge the bus.
*/
int i2c_unwedge(int port)
{
int i, j;
int ret = EC_SUCCESS;
#ifdef CONFIG_I2C_BUS_MAY_BE_UNPOWERED
/*
* Don't try to unwedge the port if we know it's unpowered; it's futile.
*/
if (!board_is_i2c_port_powered(port)) {
CPRINTS("Skipping i2c unwedge, bus not powered.");
return EC_ERROR_NOT_POWERED;
}
#endif /* CONFIG_I2C_BUS_MAY_BE_UNPOWERED */
/* Try to put port in to raw bit bang mode. */
if (i2c_raw_mode(port, 1) != EC_SUCCESS)
return EC_ERROR_UNKNOWN;
/*
* If clock is low, wait for a while in case of clock stretched
* by a slave.
*/
if (!i2c_raw_get_scl(port)) {
for (i = 0;; i++) {
if (i >= UNWEDGE_SCL_ATTEMPTS) {
/*
* If we get here, a slave is holding the clock
* low and there is nothing we can do.
*/
CPRINTS("I2C%d unwedge failed, "
"SCL is held low", port);
ret = EC_ERROR_UNKNOWN;
goto unwedge_done;
}
udelay(I2C_BITBANG_DELAY_US);
if (i2c_raw_get_scl(port))
break;
}
}
if (i2c_raw_get_sda(port))
goto unwedge_done;
CPRINTS("I2C%d unwedge called with SDA held low", port);
/* Keep trying to unwedge the SDA line until we run out of attempts. */
for (i = 0; i < UNWEDGE_SDA_ATTEMPTS; i++) {
/* Drive the clock high. */
i2c_raw_set_scl(port, 1);
udelay(I2C_BITBANG_DELAY_US);
/*
* Clock through the problem by clocking out 9 bits. If slave
* releases the SDA line, then we can stop clocking bits and
* send a STOP.
*/
for (j = 0; j < 9; j++) {
if (i2c_raw_get_sda(port))
break;
i2c_raw_set_scl(port, 0);
udelay(I2C_BITBANG_DELAY_US);
i2c_raw_set_scl(port, 1);
udelay(I2C_BITBANG_DELAY_US);
}
/* Take control of SDA line and issue a STOP command. */
i2c_raw_set_sda(port, 0);
udelay(I2C_BITBANG_DELAY_US);
i2c_raw_set_sda(port, 1);
udelay(I2C_BITBANG_DELAY_US);
/* Check if the bus is unwedged. */
if (i2c_raw_get_sda(port) && i2c_raw_get_scl(port))
break;
}
if (!i2c_raw_get_sda(port)) {
CPRINTS("I2C%d unwedge failed, SDA still low", port);
ret = EC_ERROR_UNKNOWN;
}
if (!i2c_raw_get_scl(port)) {
CPRINTS("I2C%d unwedge failed, SCL still low", port);
ret = EC_ERROR_UNKNOWN;
}
unwedge_done:
/* Take port out of raw bit bang mode. */
i2c_raw_mode(port, 0);
return ret;
}
/*****************************************************************************/
/* Host commands */
#ifdef CONFIG_I2C_DEBUG_PASSTHRU
#define PTHRUPRINTS(format, args...) CPRINTS("I2C_PTHRU " format, ## args)
#define PTHRUPRINTF(format, args...) CPRINTF(format, ## args)
#else
#define PTHRUPRINTS(format, args...)
#define PTHRUPRINTF(format, args...)
#endif
/**
* Perform the voluminous checking required for this message
*
* @param args Arguments
* @return 0 if OK, EC_RES_INVALID_PARAM on error
*/
static int check_i2c_params(const struct host_cmd_handler_args *args)
{
const struct ec_params_i2c_passthru *params = args->params;
const struct ec_params_i2c_passthru_msg *msg;
int read_len = 0, write_len = 0;
unsigned int size;
int msgnum;
if (args->params_size < sizeof(*params)) {
PTHRUPRINTS("no params, params_size=%d, need at least %d",
args->params_size, sizeof(*params));
return EC_RES_INVALID_PARAM;
}
size = sizeof(*params) + params->num_msgs * sizeof(*msg);
if (args->params_size < size) {
PTHRUPRINTS("params_size=%d, need at least %d",
args->params_size, size);
return EC_RES_INVALID_PARAM;
}
/* Loop and process messages */;
for (msgnum = 0, msg = params->msg; msgnum < params->num_msgs;
msgnum++, msg++) {
unsigned int addr_flags = msg->addr_flags;
PTHRUPRINTS("port=%d, %s, addr=0x%x(7-bit), len=%d",
params->port,
addr_flags & EC_I2C_FLAG_READ ? "read" : "write",
addr_flags & EC_I2C_ADDR_MASK,
msg->len);
if (addr_flags & EC_I2C_FLAG_READ)
read_len += msg->len;
else
write_len += msg->len;
}
/* Check there is room for the data */
if (args->response_max <
sizeof(struct ec_response_i2c_passthru) + read_len) {
PTHRUPRINTS("overflow1");
return EC_RES_INVALID_PARAM;
}
/* Must have bytes to write */
if (args->params_size < size + write_len) {
PTHRUPRINTS("overflow2");
return EC_RES_INVALID_PARAM;
}
return EC_RES_SUCCESS;
}
static int i2c_command_passthru(struct host_cmd_handler_args *args)
{
const struct ec_params_i2c_passthru *params = args->params;
const struct ec_params_i2c_passthru_msg *msg;
struct ec_response_i2c_passthru *resp = args->response;
const struct i2c_port_t *i2c_port;
const uint8_t *out;
int in_len;
int ret, i;
int port_is_locked = 0;
#ifdef CONFIG_BATTERY_CUT_OFF
/*
* Some batteries would wake up after cut-off if we talk to it.
*/
if (battery_is_cut_off())
return EC_RES_ACCESS_DENIED;
#endif
i2c_port = get_i2c_port(params->port);
if (!i2c_port)
return EC_RES_INVALID_PARAM;
ret = check_i2c_params(args);
if (ret)
return ret;
if (port_protected[params->port] && i2c_port->passthru_allowed) {
for (i = 0; i < params->num_msgs; i++) {
if (!i2c_port->passthru_allowed(i2c_port,
params->msg[i].addr_flags))
return EC_RES_ACCESS_DENIED;
}
}
/* Loop and process messages */
resp->i2c_status = 0;
out = args->params + sizeof(*params) + params->num_msgs * sizeof(*msg);
in_len = 0;
for (resp->num_msgs = 0, msg = params->msg;
resp->num_msgs < params->num_msgs;
resp->num_msgs++, msg++) {
int xferflags = I2C_XFER_START;
int read_len = 0, write_len = 0;
int rv = 1;
/* Have to remove the EC flags from the address flags */
uint16_t addr_flags = msg->addr_flags & EC_I2C_ADDR_MASK;
if (msg->addr_flags & EC_I2C_FLAG_READ)
read_len = msg->len;
else
write_len = msg->len;
/* Set stop bit for last message */
if (resp->num_msgs == params->num_msgs - 1)
xferflags |= I2C_XFER_STOP;
#if defined(VIRTUAL_BATTERY_ADDR_FLAGS) && defined(I2C_PORT_VIRTUAL_BATTERY)
if (params->port == I2C_PORT_VIRTUAL_BATTERY &&
addr_flags == VIRTUAL_BATTERY_ADDR_FLAGS) {
if (virtual_battery_handler(resp, in_len, &rv,
xferflags, read_len,
write_len, out))
break;
}
#endif
/* Transfer next message */
PTHRUPRINTS("xfer port=%x addr=0x%x rlen=%d flags=0x%x",
params->port, addr_flags,
read_len, xferflags);
if (write_len) {
PTHRUPRINTF(" out:");
for (i = 0; i < write_len; i++)
PTHRUPRINTF(" 0x%02x", out[i]);
PTHRUPRINTF("\n");
}
if (rv) {
#ifdef CONFIG_I2C_PASSTHRU_RESTRICTED
if (system_is_locked() &&
!board_allow_i2c_passthru(params->port)) {
if (port_is_locked)
i2c_lock(params->port, 0);
return EC_RES_ACCESS_DENIED;
}
#endif
if (!port_is_locked)
i2c_lock(params->port, (port_is_locked = 1));
rv = i2c_xfer_unlocked(params->port,
addr_flags,
out, write_len,
&resp->data[in_len], read_len,
xferflags);
}
if (rv) {
/* Driver will have sent a stop bit here */
if (rv == EC_ERROR_TIMEOUT)
resp->i2c_status = EC_I2C_STATUS_TIMEOUT;
else
resp->i2c_status = EC_I2C_STATUS_NAK;
break;
}
in_len += read_len;
out += write_len;
}
args->response_size = sizeof(*resp) + in_len;
/* Unlock port */
if (port_is_locked)
i2c_lock(params->port, 0);
/*
* Return success even if transfer failed so response is sent. Host
* will check message status to determine the transfer result.
*/
return EC_RES_SUCCESS;
}
DECLARE_HOST_COMMAND(EC_CMD_I2C_PASSTHRU, i2c_command_passthru, EC_VER_MASK(0));
static void i2c_passthru_protect_port(uint32_t port)
{
if (port < I2C_PORT_COUNT)
port_protected[port] = 1;
else
PTHRUPRINTS("Invalid I2C port %d to be protected\n", port);
}
static void i2c_passthru_protect_tcpc_ports(void)
{
#ifdef CONFIG_USB_PD_PORT_COUNT
int i;
/*
* If WP is not enabled i.e. system is not locked leave the tunnels open
* so that factory line can do updates without a new RO BIOS.
*/
if (!system_is_locked()) {
CPRINTS("System unlocked, TCPC I2C tunnels may be unprotected");
return;
}
for (i = 0; i < CONFIG_USB_PD_PORT_COUNT; i++) {
/* TCPC tunnel not configured. No need to protect anything */
if (!I2C_GET_ADDR(tcpc_config[i].i2c_info.addr_flags))
continue;
i2c_passthru_protect_port(tcpc_config[i].i2c_info.port);
}
#endif
}
static int i2c_command_passthru_protect(struct host_cmd_handler_args *args)
{
const struct ec_params_i2c_passthru_protect *params = args->params;
struct ec_response_i2c_passthru_protect *resp = args->response;
if (args->params_size < sizeof(*params)) {
PTHRUPRINTS("protect no params, params_size=%d, ",
args->params_size);
return EC_RES_INVALID_PARAM;
}
if (!get_i2c_port(params->port)) {
PTHRUPRINTS("protect invalid port %d", params->port);
return EC_RES_INVALID_PARAM;
}
if (params->subcmd == EC_CMD_I2C_PASSTHRU_PROTECT_STATUS) {
if (args->response_max < sizeof(*resp)) {
PTHRUPRINTS("protect no response, "
"response_max=%d, need at least %d",
args->response_max, sizeof(*resp));
return EC_RES_INVALID_PARAM;
}
resp->status = port_protected[params->port];
args->response_size = sizeof(*resp);
} else if (params->subcmd == EC_CMD_I2C_PASSTHRU_PROTECT_ENABLE) {
i2c_passthru_protect_port(params->port);
} else if (params->subcmd == EC_CMD_I2C_PASSTHRU_PROTECT_ENABLE_TCPCS) {
if (IS_ENABLED(CONFIG_USB_POWER_DELIVERY) &&
!IS_ENABLED(CONFIG_USB_PD_TCPM_STUB))
i2c_passthru_protect_tcpc_ports();
} else {
return EC_RES_INVALID_COMMAND;
}
return EC_RES_SUCCESS;
}
DECLARE_HOST_COMMAND(EC_CMD_I2C_PASSTHRU_PROTECT, i2c_command_passthru_protect,
EC_VER_MASK(0));
/*****************************************************************************/
/* Console commands */
#ifdef CONFIG_CMD_I2C_PROTECT
static int command_i2cprotect(int argc, char **argv)
{
if (argc == 1) {
int i, port;
for (i = 0; i < i2c_ports_used; i++) {
port = i2c_ports[i].port;
ccprintf("Port %d: %s\n", port,
port_protected[port] ? "Protected" : "Unprotected");
}
} else if (argc == 2) {
int port;
char *e;
port = strtoi(argv[1], &e, 0);
if (*e)
return EC_ERROR_PARAM2;
if (!get_i2c_port(port)) {
ccprintf("i2c passthru protect invalid port %d\n",
port);
return EC_RES_INVALID_PARAM;
}
port_protected[port] = 1;
} else {
return EC_ERROR_PARAM_COUNT;
}
return EC_RES_SUCCESS;
}
DECLARE_CONSOLE_COMMAND(i2cprotect, command_i2cprotect,
"[port]",
"Protect I2C bus");
#endif
#ifdef CONFIG_CMD_I2C_SCAN
static void scan_bus(int port, const char *desc)
{
int level;
uint8_t tmp;
uint16_t addr_flags;
ccprintf("Scanning %d %s", port, desc);
i2c_lock(port, 1);
/* Don't scan a busy port, since reads will just fail / time out */
level = i2c_get_line_levels(port);
if (level != I2C_LINE_IDLE) {
ccprintf(": port busy (SDA=%d, SCL=%d)",
(level & I2C_LINE_SDA_HIGH) ? 1 : 0,
(level & I2C_LINE_SCL_HIGH) ? 1 : 0);
goto scan_bus_exit;
}
/*
* Only scan in the valid client device address range, otherwise some
* client devices stretch the clock in weird ways that prevent the
* discovery of other devices.
*/
for (addr_flags = I2C_FIRST_VALID_ADDR;
addr_flags <= I2C_LAST_VALID_ADDR; ++addr_flags) {
watchdog_reload(); /* Otherwise a full scan trips watchdog */
ccputs(".");
/* Do a single read */
if (!i2c_xfer_unlocked(port, addr_flags,
NULL, 0, &tmp, 1, I2C_XFER_SINGLE))
ccprintf("\n 0x%02x", addr_flags);
}
scan_bus_exit:
i2c_lock(port, 0);
ccputs("\n");
}
static int command_scan(int argc, char **argv)
{
int port;
char *e;
if (argc == 1) {
for (port = 0; port < i2c_ports_used; port++)
scan_bus(i2c_ports[port].port, i2c_ports[port].name);
return EC_SUCCESS;
}
port = strtoi(argv[1], &e, 0);
if ((*e) || (port >= i2c_ports_used))
return EC_ERROR_PARAM2;
scan_bus(i2c_ports[port].port, i2c_ports[port].name);
return EC_SUCCESS;
}
DECLARE_CONSOLE_COMMAND(i2cscan, command_scan,
"i2cscan [port]",
"Scan I2C ports for devices");
#endif
#ifdef CONFIG_CMD_I2C_XFER
static int command_i2cxfer(int argc, char **argv)
{
int port;
uint16_t addr_flags;
uint16_t offset = 0;
uint8_t offset_size = 0;
int v = 0;
uint8_t data[32];
char *e;
int rv = 0;
if (argc < 5)
return EC_ERROR_PARAM_COUNT;
port = strtoi(argv[2], &e, 0);
if (*e)
return EC_ERROR_PARAM2;
addr_flags = strtoi(argv[3], &e, 0);
if (*e)
return EC_ERROR_PARAM3;
offset = strtoi(argv[4], &e, 0);
if (*e)
return EC_ERROR_PARAM4;
offset_size = (strlen(argv[4]) == 6) ? 2 : 1;
if (argc >= 6) {
v = strtoi(argv[5], &e, 0);
if (*e)
return EC_ERROR_PARAM5;
}
if (strcasecmp(argv[1], "r") == 0) {
/* 8-bit read */
if (offset_size == 2)
rv = i2c_read_offset16(port, addr_flags,
offset, &v, 1);
else
rv = i2c_read8(port, addr_flags,
offset, &v);
if (!rv)
ccprintf("0x%02x [%d]\n", v, v);
} else if (strcasecmp(argv[1], "r16") == 0) {
/* 16-bit read */
if (offset_size == 2)
rv = i2c_read_offset16(port, addr_flags,
offset, &v, 2);
else
rv = i2c_read16(port, addr_flags,
offset, &v);
if (!rv)
ccprintf("0x%04x [%d]\n", v, v);
} else if (strcasecmp(argv[1], "rlen") == 0) {
/* Arbitrary length read; param5 = len */
if (argc < 6 || v < 0 || v > sizeof(data))
return EC_ERROR_PARAM5;
rv = i2c_xfer(port, addr_flags,
(uint8_t *)&offset, 1, data, v);
if (!rv)
ccprintf("Data: %.*h\n", v, data);
} else if (strcasecmp(argv[1], "w") == 0) {
/* 8-bit write */
if (argc < 6)
return EC_ERROR_PARAM5;
if (offset_size == 2)
rv = i2c_write_offset16(port, addr_flags,
offset, v, 1);
else
rv = i2c_write8(port, addr_flags,
offset, v);
} else if (strcasecmp(argv[1], "w16") == 0) {
/* 16-bit write */
if (argc < 6)
return EC_ERROR_PARAM5;
if (offset_size == 2)
rv = i2c_write_offset16(port, addr_flags,
offset, v, 2);
else
rv = i2c_write16(port, addr_flags,
offset, v);
} else {
return EC_ERROR_PARAM1;
}
return rv;
}
DECLARE_CONSOLE_COMMAND(i2cxfer, command_i2cxfer,
"r/r16/rlen/w/w16 port addr offset [value | len]",
"Read write I2C");
#endif
#ifdef CONFIG_CMD_I2C_STRESS_TEST
static void i2c_test_status(struct i2c_test_results *i2c_test, int test_dev)
{
ccprintf("test_dev=%2d, ", test_dev);
ccprintf("r=%5d, rs=%5d, rf=%5d, ",
i2c_test->read_success + i2c_test->read_fail,
i2c_test->read_success,
i2c_test->read_fail);
ccprintf("w=%5d, ws=%5d, wf=%5d\n",
i2c_test->write_success + i2c_test->write_fail,
i2c_test->write_success,
i2c_test->write_fail);
i2c_test->read_success = 0;
i2c_test->read_fail = 0;
i2c_test->write_success = 0,
i2c_test->write_fail = 0;
}
#define I2C_STRESS_TEST_DATA_VERIFY_RETRY_COUNT 3
static int command_i2ctest(int argc, char **argv)
{
char *e;
int i, j, rv;
uint32_t rand;
int data, data_verify;
int count = 10000;
int udelay = 100;
int test_dev = i2c_test_dev_used;
struct i2c_stress_test_dev *i2c_s_test = NULL;
struct i2c_test_reg_info *reg_s_info;
struct i2c_test_results *test_s_results;
if (argc > 1) {
count = strtoi(argv[1], &e, 0);
if (*e)
return EC_ERROR_PARAM2;
}
if (argc > 2) {
udelay = strtoi(argv[2], &e, 0);
if (*e)
return EC_ERROR_PARAM3;
}
if (argc > 3) {
test_dev = strtoi(argv[3], &e, 0);
if (*e || test_dev < 1 || test_dev > i2c_test_dev_used)
return EC_ERROR_PARAM4;
test_dev--;
}
for (i = 0; i < count; i++) {
int port;
uint16_t addr_flags;
if (!(i % 1000))
ccprintf("running test %d\n", i);
if (argc < 4) {
rand = get_time().val;
test_dev = rand % i2c_test_dev_used;
}
port = i2c_stress_tests[test_dev].port;
addr_flags = i2c_stress_tests[test_dev].addr_flags;
i2c_s_test = i2c_stress_tests[test_dev].i2c_test;
reg_s_info = &i2c_s_test->reg_info;
test_s_results = &i2c_s_test->test_results;
rand = get_time().val;
if (rand & 0x1) {
/* read */
rv = i2c_s_test->i2c_read ?
i2c_s_test->i2c_read(port, addr_flags,
reg_s_info->read_reg, &data) :
i2c_s_test->i2c_read_dev(
reg_s_info->read_reg, &data);
if (rv || data != reg_s_info->read_val)
test_s_results->read_fail++;
else
test_s_results->read_success++;
} else {
/*
* Reads are more than writes in the system.
* Read and then write same value to ensure we are
* not changing any settings.
*/
/* Read the write register */
rv = i2c_s_test->i2c_read ?
i2c_s_test->i2c_read(port, addr_flags,
reg_s_info->read_reg, &data) :
i2c_s_test->i2c_read_dev(
reg_s_info->read_reg, &data);
if (rv) {
/* Skip writing invalid data */
test_s_results->read_fail++;
continue;
} else
test_s_results->read_success++;
j = I2C_STRESS_TEST_DATA_VERIFY_RETRY_COUNT;
do {
/* Write same value back */
rv = i2c_s_test->i2c_write ?
i2c_s_test->i2c_write(port,
addr_flags,
reg_s_info->write_reg, data) :
i2c_s_test->i2c_write_dev(
reg_s_info->write_reg, data);
i++;
if (rv) {
/* Skip reading as write failed */
test_s_results->write_fail++;
break;
}
test_s_results->write_success++;
/* Read back to verify the data */
rv = i2c_s_test->i2c_read ?
i2c_s_test->i2c_read(port,
addr_flags,
reg_s_info->read_reg, &data_verify) :
i2c_s_test->i2c_read_dev(
reg_s_info->read_reg, &data_verify);
i++;
if (rv) {
/* Read failed try next time */
test_s_results->read_fail++;
break;
} else if (!rv && data != data_verify) {
/* Either data writes/read is wrong */
j--;
} else {
j = 0;
test_s_results->read_success++;
}
} while (j);
}
usleep(udelay);
}
ccprintf("\n**********final result **********\n");
cflush();
if (argc > 3) {
i2c_test_status(&i2c_s_test->test_results, test_dev + 1);
} else {
for (i = 0; i < i2c_test_dev_used; i++) {
i2c_s_test = i2c_stress_tests[i].i2c_test;
i2c_test_status(&i2c_s_test->test_results, i + 1);
msleep(100);
}
}
cflush();
return EC_SUCCESS;
}
DECLARE_CONSOLE_COMMAND(i2ctest, command_i2ctest,
"i2ctest count|udelay|dev",
"I2C stress test");
#endif /* CONFIG_CMD_I2C_STRESS_TEST */
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