From ef5c4b9f30da2f4b9a0edd4231e95b3ef8a88d43 Mon Sep 17 00:00:00 2001 From: Barry Carter Date: Mon, 3 Sep 2012 17:45:58 +0100 Subject: - tx and rx callbacks for each module - Callbacks can be called after each read/write cycle or per byte - Each I2C module can have different callbacks - General call support also working - Supports master and slave at same time. Also works with multimaster Usage: i2c_msg msg; char buffer[255]; main() { i2c_slave_enable(I2C1, I2C_FAST_MODE | I2C_SLAVE_DUAL_ADDRESS | I2C_SLAVE_GENERAL_CALL | I2C_SLAVE_USE_RX_BUFFER); // init slave mode. Enables master too i2c_slave_attach_recv_handler(I2C1, pmsg, funcrx); // attach receive handler i2c_slave_attach_transmit_handler(I2C1, pmsg, functx); // attach transmit handler i2c_slave_set_own_address(I2C1, 0x10); // set addresss 1 i2c_slave_set_own_address2(I2C1, 0x20); // set addresss 2 } void funcrx(i2c_msg *msg) { printf("length is %d.\n", msg->length); char return_data = msg0>data[0]; } void functx(i2c_msg *dev) { msg->data[0] = 0x01; msg->data[1] = 0x02; msg->data[2] = 0x03; msg->data[3] = 0x04; msg->data[4] = 0x05; msg->length = 5; } All code derived from datasheets and libmaple. Signed-off-by:- Barry Carter --- libmaple/include/libmaple/i2c.h | 52 ++++++++++++++++++++++++++++++++++ libmaple/include/libmaple/i2c_common.h | 14 +++++++++ 2 files changed, 66 insertions(+) (limited to 'libmaple/include') diff --git a/libmaple/include/libmaple/i2c.h b/libmaple/include/libmaple/i2c.h index ff1c313..d4eac61 100644 --- a/libmaple/include/libmaple/i2c.h +++ b/libmaple/include/libmaple/i2c.h @@ -93,6 +93,7 @@ typedef struct i2c_msg { #define I2C_MSG_READ 0x1 #define I2C_MSG_10BIT_ADDR 0x2 + /** * Bitwise OR of: * - I2C_MSG_READ (write is default) @@ -197,6 +198,10 @@ typedef struct i2c_msg { #define I2C_DUTY_16_9 0x2 // 16/9 duty ratio /* Flag 0x4 is reserved; DO NOT USE. */ #define I2C_BUS_RESET 0x8 // Perform a bus reset +#define I2C_SLAVE_USE_RX_BUFFER 0x10 // Use a buffered message when doing a slave recv +#define I2C_SLAVE_USE_TX_BUFFER 0x20 // Use a buffered message when doing a slave transmit +#define I2C_SLAVE_DUAL_ADDRESS 0x40 // Enable the dual slave address scheme +#define I2C_SLAVE_GENERAL_CALL 0x80 // Enable the dual slave address scheme void i2c_master_enable(i2c_dev *dev, uint32 flags); #define I2C_ERROR_PROTOCOL (-1) @@ -406,6 +411,53 @@ static inline void i2c_set_trise(i2c_dev *dev, uint32 trise) { dev->regs->TRISE = trise; } +/* Barry Carter + * Slave support + */ + +/** + * @brief Enable Dual addressing mode to allow peripheral to have 2 addresses + * @param dev I2C device + */ +static inline void i2c_slave_dual_address_enable(i2c_dev *dev) { + dev->regs->OAR2 |= I2C_OAR2_ENDUAL; +} + +/** + * @brief Enable General Call to allow the unit to respond on addr 0x00 + * @param dev I2C device + */ +static inline void i2c_slave_general_call_enable(i2c_dev *dev) { + dev->regs->CR1 |= I2C_CR1_ENGC; +} + +/* callback functions */ +/* Callback handler for data received over the bus */ +void i2c_slave_attach_recv_handler(i2c_dev *dev, i2c_msg *msg, i2c_slave_recv_callback_func func); + +/* Callback handler for data being requested over the bus + * The callback function must call i2c_write to get the data over the bus + */ +void i2c_slave_attach_transmit_handler(i2c_dev *dev, i2c_msg *msg, i2c_slave_transmit_callback_func func); + +/** + * @brief Set the primary I2c slave address + * @param dev I2C device + * @param address the 8 or 10 bit i2c address + */ +static inline void i2c_slave_set_own_address(i2c_dev *dev, uint16 address) { + dev->regs->OAR1 = address <<1; +} + +/** + * @brief Set the secondary I2c slave address + * @param dev I2C device + * @param address the 8 or 10 bit i2c address + */ +static inline void i2c_slave_set_own_address2(i2c_dev *dev, uint16 address) { +dev->regs->OAR2 = (address <<1 ) | I2C_OAR2_ENDUAL; +} + #ifdef __cplusplus } #endif diff --git a/libmaple/include/libmaple/i2c_common.h b/libmaple/include/libmaple/i2c_common.h index 17cabe3..5debcb8 100644 --- a/libmaple/include/libmaple/i2c_common.h +++ b/libmaple/include/libmaple/i2c_common.h @@ -52,9 +52,12 @@ typedef enum i2c_state { I2C_STATE_IDLE = 1, /**< Idle */ I2C_STATE_XFER_DONE = 2, /**< Done with transfer */ I2C_STATE_BUSY = 3, /**< Busy */ + I2C_STATE_SL_RX = 4, /**< Slave receiving */ I2C_STATE_ERROR = -1 /**< Error occurred */ } i2c_state; +typedef void (*i2c_slave_recv_callback_func)(struct i2c_msg *); +typedef void (*i2c_slave_transmit_callback_func)(struct i2c_msg *); /** * @brief I2C device type. */ @@ -88,6 +91,17 @@ typedef struct i2c_dev { nvic_irq_num ev_nvic_line; /**< Event IRQ number */ nvic_irq_num er_nvic_line; /**< Error IRQ number */ volatile i2c_state state; /**< Device state */ + uint32 config_flags; /**< Configuration flags */ + + /* Barry Carter + * Slave implementation. Callback functions in this struct allow + * for a separate callback function for each I2C unit available onboard + */ + i2c_slave_transmit_callback_func i2c_slave_transmit_callback; + i2c_slave_recv_callback_func i2c_slave_recv_callback; + + struct i2c_msg *i2c_slave_msg; /* the message that the i2c slave will use */ + } i2c_dev; #endif -- cgit v1.2.3