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/**
* \file
*
* \brief I2C Slave Interrupt Driver for SAMB
*
* Copyright (C) 2015-2016 Atmel Corporation. All rights reserved.
*
* \asf_license_start
*
* \page License
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* 3. The name of Atmel may not be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* 4. This software may only be redistributed and used in connection with an
* Atmel microcontroller product.
*
* THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
* EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* \asf_license_stop
*
*/
/*
* Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
*/
#include "i2c_slave.h"
#if I2C_SLAVE_CALLBACK_MODE == true
#include "i2c_slave_interrupt.h"
#endif
/**
* \brief Gets the I<SUP>2</SUP>C master default configurations
*
* Use to initialize the configuration structure to known default values.
*
* The default configuration is as follows:
* - I2C core I2C_CORE1
* - Clock sourc I2C_CLK_INPUT_3
* - Clock divider = 0x10
* - Pinmux pad0 PINMUX_LP_GPIO_8_MUX2_I2C0_SDA
* - Pinmux pad1 PINMUX_LP_GPIO_9_MUX2_I2C0_SCK
*
* \param[out] config Pointer to configuration structure to be initiated
*/
void i2c_slave_get_config_defaults(
struct i2c_slave_config *const config)
{
/* Sanity check */
Assert(config);
config->clock_source = I2C_CLK_INPUT_3;
config->clock_divider = 0x10;
config->pin_number_pad0 = PIN_LP_GPIO_8;
config->pin_number_pad1 = PIN_LP_GPIO_9;
config->pinmux_sel_pad0 = ((PIN_LP_GPIO_8 << 16) | MUX_LP_GPIO_8_I2C0_SDA);
config->pinmux_sel_pad1 = ((PIN_LP_GPIO_9 << 16) | MUX_LP_GPIO_9_I2C0_SCL);
}
/**
* \internal Sets configurations to module
*
* \param[out] module Pointer to software module structure
* \param[in] config Configuration structure with configurations to set
*
* \return Status of setting configuration.
* \retval STATUS_OK If module was configured correctly
* \retval STATUS_ERR_ALREADY_INITIALIZED If setting other GCLK generator than
* previously set
* \retval STATUS_ERR_BAUDRATE_UNAVAILABLE If given baud rate is not compatible
* with set GCLK frequency
*/
static enum status_code _i2c_slave_set_config(
struct i2c_slave_module *const module,
const struct i2c_slave_config *const config)
{
/* Sanity check */
Assert(module);
Assert(module->hw);
Assert(config);
enum status_code status = STATUS_OK;
I2c *const i2c_module = (module->hw);
/* Set the pinmux for this i2c module. */
gpio_pinmux_cofiguration(config->pin_number_pad0, (uint16_t)(config->pinmux_sel_pad0));
gpio_pinmux_cofiguration(config->pin_number_pad1, (uint16_t)(config->pinmux_sel_pad1));
/* Find and set baudrate. */
i2c_module->CLOCK_SOURCE_SELECT.reg = config->clock_source;
i2c_module->I2C_CLK_DIVIDER.reg = I2C_CLK_DIVIDER_I2C_DIVIDE_RATIO(config->clock_divider);
/* I2C slave address */
i2c_module->I2C_SLAVE_ADDRESS.reg = I2C_SLAVE_ADDRESS_ADDRESS(config->address);
/* I2C slave mode */
i2c_module->I2C_MASTER_MODE.reg = I2C_MASTER_MODE_MASTER_ENABLE_0;
return status;
}
/**
* \brief Initializes the requested I<SUP>2</SUP>C hardware module
*
* Initializes the I<SUP>2</SUP>C slave device requested and sets the provided
* software module struct. Run this function before any further use of
* the driver.
*
* \param[out] module Pointer to software module struct
* \param[in] config Pointer to the configuration struct
*
* \return Status of initialization.
* \retval STATUS_OK Module initiated correctly
* \retval STATUS_ERR_INVALID_ARG Invalid argument in module or config structure.
* \retval STATUS_ERR_ALREADY_INITIALIZED If the Pinmux is not a valid one for I2C signals.
*
*/
enum status_code i2c_slave_init(
struct i2c_slave_module *const module,
I2c *const hw,
const struct i2c_slave_config *const config)
{
/* Sanity check */
Assert(module);
Assert(module->hw);
Assert(config);
module->hw = hw;
/* Sanity check arguments. */
if ((module == NULL) || (config == NULL))
return STATUS_ERR_INVALID_ARG;
i2c_disable(module->hw);
if (module->hw == I2C0)
system_peripheral_reset(PERIPHERAL_I2C0_CORE);
else if (module->hw == I2C1) {
system_peripheral_reset(PERIPHERAL_I2C1_CORE);
} else {
return STATUS_ERR_INVALID_ARG;
}
#if I2C_SLAVE_CALLBACK_MODE == true
/* Initialize values in module. */
module->registered_callback = 0;
module->enabled_callback = 0;
module->buffer_length = 0;
module->buffer_remaining = 0;
module->buffer = NULL;
module->status = STATUS_OK;
_i2c_instances = (void*)module;
if (module->hw == I2C0) {
system_register_isr(RAM_ISR_TABLE_I2CRX0_INDEX, (uint32_t)_i2c_slave_rx_isr_handler);
system_register_isr(RAM_ISR_TABLE_I2CTX0_INDEX, (uint32_t)_i2c_slave_tx_isr_handler);
NVIC_EnableIRQ(I2C0_RX_IRQn);
NVIC_EnableIRQ(I2C0_TX_IRQn);
} else if (module->hw == I2C1) {
system_register_isr(RAM_ISR_TABLE_I2CRX1_INDEX, (uint32_t)_i2c_slave_rx_isr_handler);
system_register_isr(RAM_ISR_TABLE_I2CTX1_INDEX, (uint32_t)_i2c_slave_tx_isr_handler);
NVIC_EnableIRQ(I2C1_RX_IRQn);
NVIC_EnableIRQ(I2C1_TX_IRQn);
}
#endif
/* Set config and return status. */
if(_i2c_slave_set_config(module, config) != STATUS_OK)
return STATUS_ERR_NOT_INITIALIZED;
return STATUS_OK;
}
/**
* \brief Reads a packet from the master
*
* Reads a packet from the master. This will wait for the master to issue a
* request.
*
* \param[in] module Pointer to software module structure
* \param[out] packet Packet to read from master
*
* \return Status of packet read.
* \retval STATUS_OK Packet was read successfully
* \retval STATUS_ERR_INVALID_ARG Invalid argument(s) was provided
*/
enum status_code i2c_slave_read_packet_wait(
struct i2c_slave_module *const module,
struct i2c_slave_packet *const packet)
{
/* Sanity check */
Assert(module);
Assert(module->hw);
Assert(packet);
I2c *const i2c_module = (module->hw);
uint16_t counter = 0;
uint32_t status = 0;
uint16_t length = packet->data_length;
if (length == 0) {
return STATUS_ERR_INVALID_ARG;
}
do {
status = i2c_module->RECEIVE_STATUS.reg;
if (status & I2C_RECEIVE_STATUS_RX_FIFO_NOT_EMPTY)
packet->data[counter++] = i2c_module->RECEIVE_DATA.reg;
} while (counter < length);
/* Now check whether the core has sent the data out and free the bus. */
while (!(status & I2C_TRANSMIT_STATUS_TX_FIFO_EMPTY)) {
status = i2c_module->TRANSMIT_STATUS.reg;
}
return STATUS_OK;
}
/**
* \brief Writes a packet to the master
*
* Writes a packet to the master. This will wait for the master to issue
* a request.
*
* \param[in] module Pointer to software module structure
* \param[in] packet Packet to write to master
*
* \return Status of packet write.
* \retval STATUS_OK Packet was written successfully
* \retval STATUS_ERR_INVALID_ARG Invalid argument(s) was provided
*/
enum status_code i2c_slave_write_packet_wait(
struct i2c_slave_module *const module,
struct i2c_slave_packet *const packet)
{
I2c *const i2c_module = (module->hw);
uint16_t i = 0;
uint32_t status = 0;
uint16_t length = packet->data_length;
if (length == 0) {
return STATUS_ERR_INVALID_ARG;
}
i2c_wait_for_idle(i2c_module);
/* Flush the FIFO */
i2c_module->I2C_FLUSH.reg = 1;
do {
status = i2c_module->TRANSMIT_STATUS.reg;
if (status & I2C_TRANSMIT_STATUS_TX_FIFO_NOT_FULL_Msk) {
i2c_module->TRANSMIT_DATA.reg = packet->data[i++];
}
} while (i < length);
/* Now check whether the core has sent the data out and its good to free the bus */
while (!(status & I2C_TRANSMIT_STATUS_TX_FIFO_EMPTY)) {
status = i2c_module->TRANSMIT_STATUS.reg;
}
return STATUS_OK;
}
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