diff options
author | Nick Sanders <nsanders@chromium.org> | 2016-10-28 16:23:12 -0700 |
---|---|---|
committer | chrome-bot <chrome-bot@chromium.org> | 2016-11-02 17:39:56 -0700 |
commit | a04fc68e721c8165ce570d8929aef1330cf72df1 (patch) | |
tree | 309d560207dc27ca6ee72b3593630282c7c93434 /include/usb_i2c.h | |
parent | d4bff62d36cf42e7b28929baff64b0d99bf95362 (diff) | |
download | chrome-ec-a04fc68e721c8165ce570d8929aef1330cf72df1.tar.gz |
usb_i2c: refactor into common
This combines stm32 and chip/g usb_i2c interfaces so they
will not diverge. Note that this fixes the chip/g implementation
to use 8-bit i2c addresses.
BUG=chrome-os-partner:57059
BRANCH=none
TEST=servod interacts with servo_micro and servo_v4
Change-Id: Ibff217d84b132556202c8a71e3d42c07d546c634
Reviewed-on: https://chromium-review.googlesource.com/405108
Commit-Ready: Nick Sanders <nsanders@chromium.org>
Tested-by: Nick Sanders <nsanders@chromium.org>
Reviewed-by: Mary Ruthven <mruthven@chromium.org>
Diffstat (limited to 'include/usb_i2c.h')
-rw-r--r-- | include/usb_i2c.h | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/include/usb_i2c.h b/include/usb_i2c.h new file mode 100644 index 0000000000..163cdfb98a --- /dev/null +++ b/include/usb_i2c.h @@ -0,0 +1,153 @@ +/* Copyright 2016 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 "consumer.h" +#include "producer.h" +#include "registers.h" +#include "task.h" +#include "usb_descriptor.h" +#include "util.h" + +#ifndef __CROS_USB_I2C_H +#define __CROS_USB_I2C_H + +/* + * Command: + * +----------+-----------+---------------+---------------+---------------+ + * | port: 1B | addr: 1B | wr count : 1B | rd count : 1B | data : <= 60B | + * +----------+-----------+---------------+---------------+---------------+ + * + * port address: 1 byte, i2c interface index + * + * slave address: 1 byte, i2c 7-bit bus address + * + * write count: 1 byte, zero based count of bytes to write + * + * read count: 1 byte, zero based count of bytes to read + * + * data: write payload up to 60 bytes of data to write, + * length must match write count + * + * Response: + * +-------------+---+---+-----------------------+ + * | status : 2B | 0 | 0 | read payload : <= 60B | + * +-------------+---+---+-----------------------+ + * + * status: 2 byte status + * 0x0000: Success + * 0x0001: I2C timeout + * 0x0002: Busy, try again + * This can happen if someone else has acquired the shared memory + * buffer that the I2C driver uses as /dev/null + * 0x0003: Write count invalid (> 60 bytes, or mismatch with payload) + * 0x0004: Read count invalid (> 60 bytes) + * 0x0005: The port specified is invalid. + * 0x8000: Unknown error mask + * The bottom 15 bits will contain the bottom 15 bits from the EC + * error code. + * + * read payload: up to 60 bytes of data read from I2C, length will match + * requested read count + */ + +enum usb_i2c_error { + USB_I2C_SUCCESS = 0x0000, + USB_I2C_TIMEOUT = 0x0001, + USB_I2C_BUSY = 0x0002, + USB_I2C_WRITE_COUNT_INVALID = 0x0003, + USB_I2C_READ_COUNT_INVALID = 0x0004, + USB_I2C_PORT_INVALID = 0x0005, + USB_I2C_UNKNOWN_ERROR = 0x8000, +}; + + +#define USB_I2C_MAX_WRITE_COUNT 60 +#define USB_I2C_MAX_READ_COUNT 60 + +BUILD_ASSERT(USB_MAX_PACKET_SIZE == (1 + 1 + 1 + 1 + USB_I2C_MAX_WRITE_COUNT)); +BUILD_ASSERT(USB_MAX_PACKET_SIZE == (2 + 1 + 1 + USB_I2C_MAX_READ_COUNT)); + +/* + * Compile time Per-USB gpio configuration stored in flash. Instances of this + * structure are provided by the user of the USB i2c. This structure binds + * together all information required to operate a USB i2c. + */ +struct usb_i2c_config { + uint16_t *buffer; + + /* Deferred function to call to handle SPI request. */ + const struct deferred_data *deferred; + + struct consumer const consumer; + struct queue const *tx_queue; +}; + +extern struct consumer_ops const usb_i2c_consumer_ops; + +/* + * Convenience macro for defining a USB I2C bridge driver. + * + * NAME is used to construct the names of the trampoline functions and the + * usb_i2c_config struct, the latter is just called NAME. + * + * INTERFACE is the index of the USB interface to associate with this + * I2C driver. + * + * INTERFACE_NAME is the index of the USB string descriptor (iInterface). + * + * ENDPOINT is the index of the USB bulk endpoint used for receiving and + * transmitting bytes. + */ +#define USB_I2C_CONFIG(NAME, \ + INTERFACE, \ + INTERFACE_NAME, \ + ENDPOINT) \ + static uint16_t \ + CONCAT2(NAME, _buffer_)[USB_MAX_PACKET_SIZE/2]; \ + static void CONCAT2(NAME, _deferred_)(void); \ + DECLARE_DEFERRED(CONCAT2(NAME, _deferred_)); \ + static struct queue const CONCAT2(NAME, _to_usb_); \ + static struct queue const CONCAT3(usb_to_, NAME, _); \ + USB_STREAM_CONFIG_FULL(CONCAT2(NAME, _usb_), \ + INTERFACE, \ + USB_CLASS_VENDOR_SPEC, \ + USB_SUBCLASS_GOOGLE_I2C, \ + USB_PROTOCOL_GOOGLE_I2C, \ + INTERFACE_NAME, \ + ENDPOINT, \ + USB_MAX_PACKET_SIZE, \ + USB_MAX_PACKET_SIZE, \ + CONCAT3(usb_to_, NAME, _), \ + CONCAT2(NAME, _to_usb_)) \ + struct usb_i2c_config const NAME = { \ + .buffer = CONCAT2(NAME, _buffer_), \ + .deferred = &CONCAT2(NAME, _deferred__data), \ + .consumer = { \ + .queue = &CONCAT3(usb_to_, NAME, _), \ + .ops = &usb_i2c_consumer_ops, \ + }, \ + .tx_queue = &CONCAT2(NAME, _to_usb_), \ + }; \ + static struct queue const CONCAT2(NAME, _to_usb_) = \ + QUEUE_DIRECT(USB_MAX_PACKET_SIZE, uint8_t, \ + null_producer, CONCAT2(NAME, _usb_).consumer); \ + static struct queue const CONCAT3(usb_to_, NAME, _) = \ + QUEUE_DIRECT(USB_MAX_PACKET_SIZE, uint8_t, \ + CONCAT2(NAME, _usb_).producer, NAME.consumer); \ + static void CONCAT2(NAME, _deferred_)(void) \ + { usb_i2c_deferred(&NAME); } + +/* + * Handle I2C request in a deferred callback. + */ +void usb_i2c_deferred(struct usb_i2c_config const *config); + +/* + * These functions should be implemented by the board to provide any board + * specific operations required to enable or disable access to the I2C device. + */ +int usb_i2c_board_enable(void); +void usb_i2c_board_disable(int debounce); +#endif /* __CROS_USB_I2C_H */ |