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BUG=b:180952272,b:180921286
BRANCH=None
TEST=Preview changes with gerrit

Exempt-From-Owner-Approval: fixing docs
Change-Id: I6583b6c7fc21248eb49a6cd71e077fbdb5de2435
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2727846
Reviewed-by: Sean Abraham <seanabraham@chromium.org>
Reviewed-by: Rob Barnes <robbarnes@google.com>
Auto-Submit: Sean Abraham <seanabraham@chromium.org>
Tested-by: Sean Abraham <seanabraham@chromium.org>

1 files changed, 4 insertions, 203 deletions

diff --git a/docs/configuration/i2c.md b/docs/configuration/i2c.md
index 7a6241e349..03d3c04909 100644
--- a/docs/configuration/i2c.md
+++ b/docs/configuration/i2c.md
@@ -1,204 +1,5 @@
-# Configure I2C Buses
+*** note
+**Warning: This document is old & has moved.  Please update any links:**<br>
+https://chromium.googlesource.com/chromiumos/platform/ec/+/HEAD/docs/configuration/i2c.md
+***
 
-## Config options
-
-The I2C options are prefixed with `CONFIG_I2C*`. Evaluate whether each option is
-appropriate to add to your board.
-
-A typical EC and board should at a minimum set `CONFIG_I2C` and
-`CONFIG_I2C_CONTROLLER`.
-
-## Feature Parameters
-
-The following parameters control the behavior of the I2C library. [config.h]
-defines a reasonable default value, but you may need to change the default value
-for your board.
-
-- `CONFIG_I2C_CHIP_MAX_TRANSFER_SIZE <bytes>`
-- `CONFIG_I2C_NACK_RETRY_COUNT <count>`
-- `CONFIG_I2C_EXTRA_PACKET_SIZE <bytes>` - Only used on STM32 EC's if
-  `CONFIG_HOSTCMD_I2C_ADDR_FLAGS` is defined.
-
-## GPIOs and Alternate Pins
-
-In the gpio.inc file, you need to define a GPIO for the clock (SCL) and data
-(SDA) pin used on each active I2C bus. The corresponding GPIOs are then included
-in the `i2c_ports[]` array. This permits the I2C library to perform common bus
-recovery actions using bit-banging without involvement by the EC-specific I2C
-device driver.
-
-You also need to define the alternate function assignment for all I2C pins using
-the `ALTERNATE()` macro.  This step can be skipped for any pins that default to
-I2C functionality.
-
-Note that many I2C buses only support 1.8V operation. This is determined by I2C
-devices connected to the bus. In this case you need to include `GPIO_SEL_1P8V`
-as part of the `flags` field in both the `GPIO()` and `ALTERNATE()` macros. I2C
-bus 0 in the example below demonstrates configuring the SCL and SDA pins for
-1.8V operation.
-
-See the [GPIO](./gpio.md) documentation for additional details on the GPIO
-macros.
-
-## Data Structures
-
-- `const struct i2c_port_t i2c_ports[]` - This array should be defined in your
-  baseboard.c or board.c file.  This array defines the mapping of internal I2C
-  port numbers used by the I2C library to the physical I2C ports connected to
-  the EC.
-- `const unsigned int i2c_port_used = ARRAY_SIZE(i2c_ports)` - Defines the
-  number of internal I2C ports accessible by the I2C library.
-
-## Tasks
-
-None required by this feature.
-
-## Testing and Debugging
-
-### Console Commands
-
-- `i2cscan` - Provides a quick look of all I2C devices found on all configured
-  buses.
-- `i2cxfer` - Allows you to read and write individual registers on an I2C
-  device.
-
-For runtime troubleshooting of an I2C device, enable and the [I2C
-tracing](../i2c-debugging.md) module to log all I2C transactions initiated by
-the EC code.
-
-## Example
-
-The image below shows the I2C bus assignment for the Volteer reference board.
-
-![I2C Example]
-
-The `gpio.inc` file for Volteer defines both `GPIO()` and `ALTERNATE()` entries for
-all I2C buses used in the design.
-
-```c
-/* I2C pins - Alternate function below configures I2C module on these pins */
-GPIO(EC_I2C0_SENSOR_SCL,       PIN(B, 5), GPIO_INPUT | GPIO_SEL_1P8V)
-GPIO(EC_I2C0_SENSOR_SDA,       PIN(B, 4), GPIO_INPUT | GPIO_SEL_1P8V)
-GPIO(EC_I2C1_USB_C0_SCL,       PIN(9, 0), GPIO_INPUT)
-GPIO(EC_I2C1_USB_C0_SDA,       PIN(8, 7), GPIO_INPUT)
-GPIO(EC_I2C2_USB_C1_SCL,       PIN(9, 2), GPIO_INPUT)
-GPIO(EC_I2C2_USB_C1_SDA,       PIN(9, 1), GPIO_INPUT)
-GPIO(EC_I2C3_USB_1_MIX_SCL,    PIN(D, 1), GPIO_INPUT)
-GPIO(EC_I2C3_USB_1_MIX_SDA,    PIN(D, 0), GPIO_INPUT)
-GPIO(EC_I2C5_POWER_SCL,        PIN(3, 3), GPIO_INPUT)
-GPIO(EC_I2C5_POWER_SDA,        PIN(3, 6), GPIO_INPUT)
-GPIO(EC_I2C7_EEPROM_SCL,       PIN(B, 3), GPIO_INPUT)
-GPIO(EC_I2C7_EEPROM_SDA,       PIN(B, 2), GPIO_INPUT)
-
-/* Alternate functions GPIO definitions */
-ALTERNATE(PIN_MASK(B, BIT(5) | BIT(4)), 0, MODULE_I2C, (GPIO_INPUT | GPIO_SEL_1P8V)) /* I2C0 */
-ALTERNATE(PIN_MASK(9, BIT(0) | BIT(2) | BIT(1)), 0, MODULE_I2C, 0)                   /* I2C1 SCL / I2C2 */
-ALTERNATE(PIN_MASK(8, BIT(7)), 0, MODULE_I2C, 0)                                     /* I2C1 SDA */
-ALTERNATE(PIN_MASK(D, BIT(1) | BIT(0)), 0, MODULE_I2C, 0)                            /* I2C3 */
-ALTERNATE(PIN_MASK(3, BIT(3) | BIT(6)), 0, MODULE_I2C, 0)                            /* I2C5 */
-ALTERNATE(PIN_MASK(B, BIT(3) | BIT(2)), 0, MODULE_I2C, 0)                            /* I2C7 */
-```
-
-The `i2c_ports[]` array requires the `.port` field to be assigned to an EC
-chipset specific enumeration. For the NPCx7 I2C bus names are defined in
-[./chip/npcx/registers.h]. The Volteer `baseboard.h` file creates a mapping
-from the schematic net name to the NPCx7 I2C bus enumeration.
-
-```c
-#define CONFIG_I2C
-#define I2C_PORT_SENSOR		NPCX_I2C_PORT0_0
-#define I2C_PORT_USB_C0		NPCX_I2C_PORT1_0
-#define I2C_PORT_USB_C1		NPCX_I2C_PORT2_0
-#define I2C_PORT_USB_1_MIX	NPCX_I2C_PORT3_0
-#define I2C_PORT_POWER		NPCX_I2C_PORT5_0
-#define I2C_PORT_EEPROM		NPCX_I2C_PORT7_0
-```
-
-The last piece for I2C configuration is to create the `i2c_ports[]` array using
-the macros and enumerations added to `baseboard.h` and `gpio.inc`.
-
-```c
-/* I2C port map configuration */
-const struct i2c_port_t i2c_ports[] = {
-	{
-		.name = "sensor",
-		.port = I2C_PORT_SENSOR,
-		.kbps = 400,
-		.scl = GPIO_EC_I2C0_SENSOR_SCL,
-		.sda = GPIO_EC_I2C0_SENSOR_SDA,
-		.flags = 0,
-	},
-	{
-		.name = "usb_c0",
-		.port = I2C_PORT_USB_C0,
-		/*
-		 * I2C buses used for PD communication must be set for 400 kbps
-		 * or greater. Set to the maximum speed supported by all devices.
-		 */
-		.kbps = 1000,
-		.scl = GPIO_EC_I2C1_USB_C0_SCL,
-		.sda = GPIO_EC_I2C1_USB_C0_SDA,
-	},
-	{
-		.name = "usb_c1",
-		.port = I2C_PORT_USB_C1,
-		/*
-		 * I2C buses used for PD communication must be set for 400 kbps
-		 * or greater. Set to the maximum speed supported by all devices.
-		 */
-		.scl = GPIO_EC_I2C2_USB_C1_SCL,
-		.sda = GPIO_EC_I2C2_USB_C1_SDA,
-	},
-	{
-		.name = "usb_1_mix",
-		.port = I2C_PORT_USB_1_MIX,
-		.kbps = 100,
-		.scl = GPIO_EC_I2C3_USB_1_MIX_SCL,
-		.sda = GPIO_EC_I2C3_USB_1_MIX_SDA,
-	},
-	{
-		.name = "power",
-		.port = I2C_PORT_POWER,
-		.kbps = 100,
-		.scl = GPIO_EC_I2C5_POWER_SCL,
-		.sda = GPIO_EC_I2C5_POWER_SDA,
-	},
-	{
-		.name = "eeprom",
-		.port = I2C_PORT_EEPROM,
-		.kbps = 400,
-		.scl = GPIO_EC_I2C7_EEPROM_SCL,
-		.sda = GPIO_EC_I2C7_EEPROM_SDA,
-	},
-};
-const unsigned int i2c_ports_used = ARRAY_SIZE(i2c_ports);
-```
-
-The `.flags` field is optional when using the default I2C bus setup. See
-[./include/i2c.h] for the full list of supported flags.
-
-The flag `I2C_PORT_FLAG_DYNAMIC_SPEED` allows the I2C bus frequency to be
-changed at runtime. The typical use case is to set the I2C bus frequency to
-different speeds based on the BOARD_VERSION in [CBI]. For example board version
-1 supports 100 kbps operation but board version 2 and greater supports 400 kbps
-operation. `I2C_PORT_FLAG_DYNAMIC_SPEED` is not used to change the I2C bus
-frequency on the fly depending on the addressed slave device.
-
-An example of changing the I2C bus frequency from the [Kodama
-board](../../board/kodama/board.c) is shown below.
-
-```c
-static void board_i2c_init(void)
-{
-	if (board_get_version() < 2)
-		i2c_set_freq(1,  I2C_FREQ_100KHZ);
-}
-DECLARE_HOOK(HOOK_INIT, board_i2c_init, HOOK_PRIO_INIT_I2C);
-```
-
-
-[config.h]: ../new_board_checklist.md#config_h
-[./chip/npcx/registers.h]: ../../chip/npcx/registers.h
-[./include/i2c.h]: ../../include/i2c.h
-[I2C Example]: ../images/i2c_example.png
-[CBI]: https://chromium.googlesource.com/chromiumos/docs/+/master/design_docs/cros_board_info.md