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authorJack Rosenthal <jrosenth@chromium.org>2021-11-04 12:11:58 -0600
committerCommit Bot <commit-bot@chromium.org>2021-11-05 04:22:34 +0000
commit252457d4b21f46889eebad61d4c0a65331919cec (patch)
tree01856c4d31d710b20e85a74c8d7b5836e35c3b98 /chip/mec1322/i2c.c
parent08f5a1e6fc2c9467230444ac9b582dcf4d9f0068 (diff)
downloadchrome-ec-stabilize-quickfix-14695.124.B-ish.tar.gz
In the interest of making long-term branch maintenance incur as little technical debt on us as possible, we should not maintain any files on the branch we are not actually using. This has the added effect of making it extremely clear when merging CLs from the main branch when changes have the possibility to affect us. The follow-on CL adds a convenience script to actually pull updates from the main branch and generate a CL for the update. BUG=b:204206272 BRANCH=ish TEST=make BOARD=arcada_ish && make BOARD=drallion_ish Signed-off-by: Jack Rosenthal <jrosenth@chromium.org> Change-Id: I17e4694c38219b5a0823e0a3e55a28d1348f4b18 Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3262038 Reviewed-by: Jett Rink <jettrink@chromium.org> Reviewed-by: Tom Hughes <tomhughes@chromium.org>
Diffstat (limited to 'chip/mec1322/i2c.c')
-rw-r--r--chip/mec1322/i2c.c531
1 files changed, 0 insertions, 531 deletions
diff --git a/chip/mec1322/i2c.c b/chip/mec1322/i2c.c
deleted file mode 100644
index aecc8abd9b..0000000000
--- a/chip/mec1322/i2c.c
+++ /dev/null
@@ -1,531 +0,0 @@
-/* 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 port module for MEC1322 */
-
-#include "common.h"
-#include "console.h"
-#include "gpio.h"
-#include "hooks.h"
-#include "i2c.h"
-#include "registers.h"
-#include "task.h"
-#include "timer.h"
-#include "util.h"
-
-#define CPUTS(outstr) cputs(CC_I2C, outstr)
-#define CPRINTS(format, args...) cprints(CC_I2C, format, ## args)
-
-#define I2C_CLOCK 16000000 /* 16 MHz */
-
-/* Status */
-#define STS_NBB BIT(0) /* Bus busy */
-#define STS_LAB BIT(1) /* Arbitration lost */
-#define STS_LRB BIT(3) /* Last received bit */
-#define STS_BER BIT(4) /* Bus error */
-#define STS_PIN BIT(7) /* Pending interrupt */
-
-/* Control */
-#define CTRL_ACK BIT(0) /* Acknowledge */
-#define CTRL_STO BIT(1) /* STOP */
-#define CTRL_STA BIT(2) /* START */
-#define CTRL_ENI BIT(3) /* Enable interrupt */
-#define CTRL_ESO BIT(6) /* Enable serial output */
-#define CTRL_PIN BIT(7) /* Pending interrupt not */
-
-/* Completion */
-#define COMP_IDLE BIT(29) /* i2c bus is idle */
-#define COMP_RW_BITS_MASK 0x3C /* R/W bits mask */
-
-/* Maximum transfer of a SMBUS block transfer */
-#define SMBUS_MAX_BLOCK_SIZE 32
-
-/*
- * Amount of time to blocking wait for i2c bus to finish. After this blocking
- * timeout, if the bus is still not finished, then allow other tasks to run.
- * Note: this is just long enough for a 400kHz bus to finish transmitting one
- * byte assuming the bus isn't being held.
- */
-#define I2C_WAIT_BLOCKING_TIMEOUT_US 25
-
-enum i2c_transaction_state {
- /* Stop condition was sent in previous transaction */
- I2C_TRANSACTION_STOPPED,
- /* Stop condition was not sent in previous transaction */
- I2C_TRANSACTION_OPEN,
-};
-
-/* I2C controller state data */
-static struct {
- /* Transaction timeout, or 0 to use default. */
- uint32_t timeout_us;
- /* Task waiting on port, or TASK_ID_INVALID if none. */
- volatile task_id_t task_waiting;
- enum i2c_transaction_state transaction_state;
-} cdata[I2C_CONTROLLER_COUNT];
-
-/* Map port number to port name in datasheet, for debug prints. */
-static const char *i2c_port_names[MEC1322_I2C_PORT_COUNT] = {
- [MEC1322_I2C0_0] = "0_0",
- [MEC1322_I2C0_1] = "0_1",
- [MEC1322_I2C1] = "1",
- [MEC1322_I2C2] = "2",
- [MEC1322_I2C3] = "3",
-};
-
-static void configure_controller_speed(int controller, int kbps)
-{
- int t_low, t_high;
- const int period = I2C_CLOCK / 1000 / kbps;
-
- /*
- * Refer to NXP UM10204 for minimum timing requirement of T_Low and
- * T_High.
- * http://www.nxp.com/documents/user_manual/UM10204.pdf
- */
- if (kbps > 400) {
- /* Fast mode plus */
- t_low = t_high = period / 2 - 1;
- MEC1322_I2C_DATA_TIM(controller) = 0x06060601;
- MEC1322_I2C_DATA_TIM_2(controller) = 0x06;
- } else if (kbps > 100) {
- /* Fast mode */
- /* By spec, clk low period is 1.3us min */
- t_low = MAX((int)(I2C_CLOCK * 1.3 / 1000000), period / 2 - 1);
- t_high = period - t_low - 2;
- MEC1322_I2C_DATA_TIM(controller) = 0x040a0a01;
- MEC1322_I2C_DATA_TIM_2(controller) = 0x0a;
- } else {
- /* Standard mode */
- t_low = t_high = period / 2 - 1;
- MEC1322_I2C_DATA_TIM(controller) = 0x0c4d5006;
- MEC1322_I2C_DATA_TIM_2(controller) = 0x4d;
- }
-
- /* Clock periods is one greater than the contents of these fields */
- MEC1322_I2C_BUS_CLK(controller) = ((t_high & 0xff) << 8) |
- (t_low & 0xff);
-}
-
-static void configure_controller(int controller, int kbps)
-{
- MEC1322_I2C_CTRL(controller) = CTRL_PIN;
- MEC1322_I2C_OWN_ADDR(controller) = 0x0;
- configure_controller_speed(controller, kbps);
- MEC1322_I2C_CTRL(controller) = CTRL_PIN | CTRL_ESO |
- CTRL_ACK | CTRL_ENI;
- MEC1322_I2C_CONFIG(controller) |= BIT(10); /* ENAB */
-
- /* Enable interrupt */
- MEC1322_I2C_CONFIG(controller) |= BIT(29); /* ENIDI */
- MEC1322_INT_ENABLE(12) |= BIT(controller);
- MEC1322_INT_BLK_EN |= BIT(12);
-}
-
-static void reset_controller(int controller)
-{
- int i;
-
- MEC1322_I2C_CONFIG(controller) |= BIT(9);
- udelay(100);
- MEC1322_I2C_CONFIG(controller) &= ~BIT(9);
-
- for (i = 0; i < i2c_ports_used; ++i)
- if (controller == i2c_port_to_controller(i2c_ports[i].port)) {
- configure_controller(controller, i2c_ports[i].kbps);
- cdata[controller].transaction_state =
- I2C_TRANSACTION_STOPPED;
- break;
- }
-}
-
-static int wait_for_interrupt(int controller, int timeout)
-{
- int event;
-
- if (timeout <= 0)
- return EC_ERROR_TIMEOUT;
-
- cdata[controller].task_waiting = task_get_current();
- task_enable_irq(MEC1322_IRQ_I2C_0 + controller);
-
- /* Wait until I2C interrupt or timeout. */
- event = task_wait_event_mask(TASK_EVENT_I2C_IDLE, timeout);
-
- task_disable_irq(MEC1322_IRQ_I2C_0 + controller);
- cdata[controller].task_waiting = TASK_ID_INVALID;
-
- return (event & TASK_EVENT_TIMER) ? EC_ERROR_TIMEOUT : EC_SUCCESS;
-}
-
-static int wait_idle(int controller)
-{
- uint8_t sts = MEC1322_I2C_STATUS(controller);
- uint64_t block_timeout = get_time().val + I2C_WAIT_BLOCKING_TIMEOUT_US;
- uint64_t task_timeout = block_timeout + cdata[controller].timeout_us;
- int rv = 0;
-
- while (!(sts & STS_NBB)) {
- if (rv)
- return rv;
- if (get_time().val > block_timeout)
- rv = wait_for_interrupt(controller,
- task_timeout - get_time().val);
- sts = MEC1322_I2C_STATUS(controller);
- }
-
- if (sts & (STS_BER | STS_LAB))
- return EC_ERROR_UNKNOWN;
- return EC_SUCCESS;
-}
-
-static int wait_byte_done(int controller)
-{
- uint8_t sts = MEC1322_I2C_STATUS(controller);
- uint64_t block_timeout = get_time().val + I2C_WAIT_BLOCKING_TIMEOUT_US;
- uint64_t task_timeout = block_timeout + cdata[controller].timeout_us;
- int rv = 0;
-
- while (sts & STS_PIN) {
- if (rv)
- return rv;
- if (get_time().val > block_timeout)
- rv = wait_for_interrupt(controller,
- task_timeout - get_time().val);
- sts = MEC1322_I2C_STATUS(controller);
- }
-
- return sts & STS_LRB;
-}
-
-static void select_port(int port)
-{
- /*
- * I2C0_1 uses port 1 of controller 0. All other I2C pin sets
- * use port 0.
- */
- uint8_t port_sel = (port == MEC1322_I2C0_1) ? 1 : 0;
- int controller = i2c_port_to_controller(port);
-
- MEC1322_I2C_CONFIG(controller) &= ~0xf;
- MEC1322_I2C_CONFIG(controller) |= port_sel;
-
-}
-
-static inline int get_line_level(int controller)
-{
- int ret, ctrl;
- /*
- * We need to enable BB (Bit Bang) mode in order to read line level
- * properly, othervise line levels return always idle (0x60).
- */
- ctrl = MEC1322_I2C_BB_CTRL(controller);
- MEC1322_I2C_BB_CTRL(controller) |= 1;
- ret = (MEC1322_I2C_BB_CTRL(controller) >> 5) & 0x3;
- MEC1322_I2C_BB_CTRL(controller) = ctrl;
- return ret;
-}
-
-static inline void push_in_buf(uint8_t **in, uint8_t val, int skip)
-{
- if (!skip) {
- **in = val;
- (*in)++;
- }
-}
-
-int chip_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 flags)
-{
- int i;
- int controller;
- int send_start = flags & I2C_XFER_START;
- int send_stop = flags & I2C_XFER_STOP;
- int skip = 0;
- int bytes_to_read;
- uint8_t reg;
- int ret_done;
-
- if (out_size == 0 && in_size == 0)
- return EC_SUCCESS;
-
- select_port(port);
- controller = i2c_port_to_controller(port);
- if (send_start &&
- cdata[controller].transaction_state == I2C_TRANSACTION_STOPPED)
- wait_idle(controller);
-
- reg = MEC1322_I2C_STATUS(controller);
- if (send_start &&
- cdata[controller].transaction_state == I2C_TRANSACTION_STOPPED &&
- (((reg & (STS_BER | STS_LAB)) || !(reg & STS_NBB)) ||
- (get_line_level(controller)
- != I2C_LINE_IDLE))) {
- CPRINTS("i2c%s bad status 0x%02x, SCL=%d, SDA=%d",
- i2c_port_names[port], reg,
- get_line_level(controller) & I2C_LINE_SCL_HIGH,
- get_line_level(controller) & I2C_LINE_SDA_HIGH);
-
- /* Attempt to unwedge the port. */
- i2c_unwedge(port);
-
- /* Bus error, bus busy, or arbitration lost. Try reset. */
- reset_controller(controller);
- select_port(port);
-
- /*
- * We don't know what edges the slave saw, so sleep long enough
- * that the slave will see the new start condition below.
- */
- usleep(1000);
- }
-
- if (out_size) {
- if (send_start) {
- MEC1322_I2C_DATA(controller) =
- (uint8_t)(I2C_STRIP_FLAGS(slave_addr_flags)
- << 1);
-
- /* Clock out the slave address, sending START bit */
- MEC1322_I2C_CTRL(controller) = CTRL_PIN | CTRL_ESO |
- CTRL_ENI | CTRL_ACK |
- CTRL_STA;
- cdata[controller].transaction_state =
- I2C_TRANSACTION_OPEN;
- }
-
- for (i = 0; i < out_size; ++i) {
- ret_done = wait_byte_done(controller);
- if (ret_done)
- goto err_chip_i2c_xfer;
- MEC1322_I2C_DATA(controller) = out[i];
- }
- ret_done = wait_byte_done(controller);
- if (ret_done)
- goto err_chip_i2c_xfer;
-
- /*
- * Send STOP bit if the stop flag is on, and caller
- * doesn't expect to receive data.
- */
- if (send_stop && in_size == 0) {
- MEC1322_I2C_CTRL(controller) = CTRL_PIN | CTRL_ESO |
- CTRL_STO | CTRL_ACK;
- cdata[controller].transaction_state =
- I2C_TRANSACTION_STOPPED;
- }
- }
-
- if (in_size) {
- /* Resend start bit when changing direction */
- if (out_size || send_start) {
- /* Repeated start case */
- if (cdata[controller].transaction_state ==
- I2C_TRANSACTION_OPEN)
- MEC1322_I2C_CTRL(controller) = CTRL_ESO |
- CTRL_STA |
- CTRL_ACK |
- CTRL_ENI;
-
- MEC1322_I2C_DATA(controller) =
- (uint8_t)(I2C_STRIP_FLAGS(slave_addr_flags)
- << 1)
- | 0x01;
-
- /* New transaction case, clock out slave address. */
- if (cdata[controller].transaction_state ==
- I2C_TRANSACTION_STOPPED)
- MEC1322_I2C_CTRL(controller) = CTRL_ESO |
- CTRL_STA |
- CTRL_ACK |
- CTRL_ENI |
- CTRL_PIN;
-
- cdata[controller].transaction_state =
- I2C_TRANSACTION_OPEN;
-
- /* Skip over the unused byte */
- skip = 1;
- in_size++;
- }
-
- /* Special flags need to be set for last two bytes */
- bytes_to_read = send_stop ? in_size - 2 : in_size;
-
- for (i = 0; i < bytes_to_read; ++i) {
- ret_done = wait_byte_done(controller);
- if (ret_done)
- goto err_chip_i2c_xfer;
- push_in_buf(&in, MEC1322_I2C_DATA(controller), skip);
- skip = 0;
- }
- ret_done = wait_byte_done(controller);
- if (ret_done)
- goto err_chip_i2c_xfer;
-
- if (send_stop) {
- /*
- * De-assert ACK bit before reading the next to last
- * byte, so that the last byte is NACK'ed.
- */
- MEC1322_I2C_CTRL(controller) = CTRL_ESO | CTRL_ENI;
- push_in_buf(&in, MEC1322_I2C_DATA(controller), skip);
- ret_done = wait_byte_done(controller);
- if (ret_done)
- goto err_chip_i2c_xfer;
-
- /* Send STOP */
- MEC1322_I2C_CTRL(controller) =
- CTRL_PIN | CTRL_ESO | CTRL_ACK | CTRL_STO;
-
- cdata[controller].transaction_state =
- I2C_TRANSACTION_STOPPED;
-
- /*
- * We need to know our stop point two bytes in
- * advance. If we don't know soon enough, we need
- * to do an extra read (to last_addr + 1) to
- * issue the stop.
- */
- push_in_buf(&in, MEC1322_I2C_DATA(controller),
- in_size == 1);
- }
- }
-
- /* Check for error conditions */
- if (MEC1322_I2C_STATUS(controller) & (STS_LAB | STS_BER))
- return EC_ERROR_UNKNOWN;
-
- return EC_SUCCESS;
-err_chip_i2c_xfer:
- /* Send STOP and return error */
- MEC1322_I2C_CTRL(controller) = CTRL_PIN | CTRL_ESO |
- CTRL_STO | CTRL_ACK;
- cdata[controller].transaction_state = I2C_TRANSACTION_STOPPED;
- if (ret_done == STS_LRB)
- return EC_ERROR_BUSY;
- else if (ret_done == EC_ERROR_TIMEOUT) {
- /*
- * If our transaction timed out then our i2c controller
- * may be wedged without showing any other outward signs
- * of failure. Reset the controller so that future
- * transactions have a chance of success.
- */
- reset_controller(controller);
- return EC_ERROR_TIMEOUT;
- }
- else
- return EC_ERROR_UNKNOWN;
-}
-
-int i2c_raw_get_scl(int port)
-{
- enum gpio_signal g;
-
- /* If no SCL pin defined for this port, then return 1 to appear idle. */
- if (get_scl_from_i2c_port(port, &g) != EC_SUCCESS)
- return 1;
-
- return gpio_get_level(g);
-}
-
-int i2c_raw_get_sda(int port)
-{
- enum gpio_signal g;
-
- /* If no SDA pin defined for this port, then return 1 to appear idle. */
- if (get_sda_from_i2c_port(port, &g) != EC_SUCCESS)
- return 1;
-
- return gpio_get_level(g);
-}
-
-int i2c_get_line_levels(int port)
-{
- int rv;
-
- i2c_lock(port, 1);
- select_port(port);
- rv = get_line_level(i2c_port_to_controller(port));
- i2c_lock(port, 0);
- return rv;
-}
-
-int i2c_port_to_controller(int port)
-{
- if (port < 0 || port >= MEC1322_I2C_PORT_COUNT)
- return -1;
- return (port == MEC1322_I2C0_0) ? 0 : port - 1;
-}
-
-void i2c_set_timeout(int port, uint32_t timeout)
-{
- /* Param is port, but timeout is stored by-controller. */
- cdata[i2c_port_to_controller(port)].timeout_us =
- timeout ? timeout : I2C_TIMEOUT_DEFAULT_US;
-}
-
-void i2c_init(void)
-{
- int i;
- int controller;
- int controller0_kbps = -1;
-
- /* Configure GPIOs */
- gpio_config_module(MODULE_I2C, 1);
-
- for (i = 0; i < i2c_ports_used; ++i) {
- /*
- * If this controller has multiple ports, check if we already
- * configured it. If so, ensure previously configured bitrate
- * matches.
- */
- controller = i2c_port_to_controller(i2c_ports[i].port);
- if (controller == 0) {
- if (controller0_kbps != -1) {
- ASSERT(controller0_kbps == i2c_ports[i].kbps);
- continue;
- }
- controller0_kbps = i2c_ports[i].kbps;
- }
- configure_controller(controller, i2c_ports[i].kbps);
- cdata[controller].task_waiting = TASK_ID_INVALID;
- cdata[controller].transaction_state = I2C_TRANSACTION_STOPPED;
-
- /* Use default timeout. */
- i2c_set_timeout(i2c_ports[i].port, 0);
- }
-}
-
-static void handle_interrupt(int controller)
-{
- int id = cdata[controller].task_waiting;
-
- /* Clear the interrupt status */
- MEC1322_I2C_COMPLETE(controller) &= (COMP_RW_BITS_MASK | COMP_IDLE);
-
- /*
- * Write to control register interferes with I2C transaction.
- * Instead, let's disable IRQ from the core until the next time
- * we want to wait for STS_PIN/STS_NBB.
- */
- task_disable_irq(MEC1322_IRQ_I2C_0 + controller);
-
- /* Wake up the task which was waiting on the I2C interrupt, if any. */
- if (id != TASK_ID_INVALID)
- task_set_event(id, TASK_EVENT_I2C_IDLE);
-}
-
-void i2c0_interrupt(void) { handle_interrupt(0); }
-void i2c1_interrupt(void) { handle_interrupt(1); }
-void i2c2_interrupt(void) { handle_interrupt(2); }
-void i2c3_interrupt(void) { handle_interrupt(3); }
-
-DECLARE_IRQ(MEC1322_IRQ_I2C_0, i2c0_interrupt, 2);
-DECLARE_IRQ(MEC1322_IRQ_I2C_1, i2c1_interrupt, 2);
-DECLARE_IRQ(MEC1322_IRQ_I2C_2, i2c2_interrupt, 2);
-DECLARE_IRQ(MEC1322_IRQ_I2C_3, i2c3_interrupt, 2);