From d3912549a36fb4077b24869472065f66b8e24a3a Mon Sep 17 00:00:00 2001 From: danicampora Date: Wed, 18 Mar 2015 13:16:09 +0100 Subject: [PATCH] cc3200: Improve I2C timeout handling. --- cc3200/mods/pybi2c.c | 71 ++++++++++++++++++++++++-------------------- 1 file changed, 39 insertions(+), 32 deletions(-) diff --git a/cc3200/mods/pybi2c.c b/cc3200/mods/pybi2c.c index ce7bc0e74d..3f8a9a1fcf 100644 --- a/cc3200/mods/pybi2c.c +++ b/cc3200/mods/pybi2c.c @@ -43,6 +43,7 @@ #include "pybi2c.h" #include "mpexception.h" #include "pybsleep.h" +#include "utils.h" /// \moduleref pyb /// \class I2C - a two-wire serial protocol @@ -95,7 +96,7 @@ typedef struct _pyb_i2c_obj_t { mp_obj_base_t base; - int mode; + uint mode; union { uint baudrate; byte slvaddr; @@ -109,9 +110,10 @@ typedef struct _pyb_i2c_obj_t { #define PYBI2C_MODE_MASTER (0) #define PYBI2C_MODE_SLAVE (1) -#define PYBI2C_DEF_TIMEOUT_MS (7) +#define PYBI2C_DEF_TIMEOUT_MS (5) +#define PYBI2C_TRANSAC_WAIT_DELAY_US (10) -#define PYBI2C_TIMEOUT_TO_COUNT(to_ms, baud) (((baud) * to_ms) / 16000) +#define PYBI2C_TIMEOUT_TO_COUNT(to_us, baud) (((baud) * to_us) / 16000000) #define RET_IF_ERR(Func) { \ if (!Func) { \ @@ -122,7 +124,7 @@ typedef struct _pyb_i2c_obj_t { /****************************************************************************** DECLARE PRIVATE DATA ******************************************************************************/ -STATIC pyb_i2c_obj_t pyb_i2c_obj; +STATIC pyb_i2c_obj_t pyb_i2c_obj; /****************************************************************************** DEFINE PRIVATE FUNCTIONS @@ -132,7 +134,6 @@ STATIC void i2c_init (pyb_i2c_obj_t *self) { // Enable the I2C Peripheral MAP_PRCMPeripheralClkEnable(PRCM_I2CA0, PRCM_RUN_MODE_CLK | PRCM_SLP_MODE_CLK); MAP_PRCMPeripheralReset(PRCM_I2CA0); - // Configure I2C module with the specified baudrate MAP_I2CMasterInitExpClk(I2CA0_BASE, self->baudrate); } @@ -142,20 +143,27 @@ STATIC void i2c_deinit(void) { MAP_PRCMPeripheralClkDisable(PRCM_I2CA0, PRCM_RUN_MODE_CLK | PRCM_SLP_MODE_CLK); } -/******************************************************************************/ -/* Micro Python bindings */ -/******************************************************************************/ - -STATIC bool pybI2C_transaction(uint cmd, uint timeout) { +STATIC bool pybI2C_transaction(uint cmd, int timeout) { + // Sanity check, t_timeout must be between 1 and 255 + // convert timeout to microseconds + timeout = timeout > 0 ? (timeout * 1000) : 1000; + uint t_timeout = MIN(PYBI2C_TIMEOUT_TO_COUNT(timeout, pyb_i2c_obj.baudrate), 255); // Clear all interrupts MAP_I2CMasterIntClearEx(I2CA0_BASE, MAP_I2CMasterIntStatusEx(I2CA0_BASE, false)); - // Set the time-out. Not to be used with breakpoints. - MAP_I2CMasterTimeoutSet(I2CA0_BASE, timeout); + // Set the time-out in terms of clock cycles. Not to be used with breakpoints. + MAP_I2CMasterTimeoutSet(I2CA0_BASE, t_timeout); // Initiate the transfer. MAP_I2CMasterControl(I2CA0_BASE, cmd); // Wait until the current byte has been transferred. // Poll on the raw interrupt status. - while ((MAP_I2CMasterIntStatusEx(I2CA0_BASE, false) & (I2C_MASTER_INT_DATA | I2C_MASTER_INT_TIMEOUT)) == 0); + while ((MAP_I2CMasterIntStatusEx(I2CA0_BASE, false) & (I2C_MASTER_INT_DATA | I2C_MASTER_INT_TIMEOUT)) == 0) { + // wait for a few microseconds + UtilsDelay(UTILS_DELAY_US_TO_COUNT(PYBI2C_TRANSAC_WAIT_DELAY_US)); + timeout -= PYBI2C_TRANSAC_WAIT_DELAY_US; + if (timeout < 0) { + return false; + } + } // Check for any errors in transfer if (MAP_I2CMasterErr(I2CA0_BASE) != I2C_MASTER_ERR_NONE) { @@ -179,8 +187,7 @@ STATIC bool pybI2C_transaction(uint cmd, uint timeout) { return true; } -STATIC bool pybI2C_Write(byte devAddr, byte *data, uint len, bool stop, uint timeout) { - +STATIC bool pybI2C_Write(byte devAddr, byte *data, uint len, bool stop, int timeout) { // Set I2C codec slave address MAP_I2CMasterSlaveAddrSet(I2CA0_BASE, devAddr, false); // Write the first byte to the controller. @@ -204,7 +211,7 @@ STATIC bool pybI2C_Write(byte devAddr, byte *data, uint len, bool stop, uint tim return true; } -STATIC bool pybI2C_Read(byte devAddr, byte *data, uint len, uint timeout) { +STATIC bool pybI2C_Read(byte devAddr, byte *data, uint len, int timeout) { uint cmd; // Set I2C codec slave address @@ -244,7 +251,7 @@ STATIC bool pybI2C_Read(byte devAddr, byte *data, uint len, uint timeout) { return true; } -STATIC bool pybI2C_ScanDevice(byte devAddr, uint timeout) { +STATIC bool pybI2C_ScanDevice(byte devAddr, int timeout) { // Set I2C codec slave address MAP_I2CMasterSlaveAddrSet(I2CA0_BASE, devAddr, true); // Initiate the transfer. @@ -270,6 +277,10 @@ STATIC void pyb_i2c_print(void (*print)(void *env, const char *fmt, ...), void * } } +/******************************************************************************/ +/* Micro Python bindings */ +/******************************************************************************/ + /// \method init(mode, *, addr=0x12, baudrate=400000) /// /// Initialise the I2C bus with the given parameters: @@ -374,7 +385,7 @@ STATIC mp_obj_t pyb_i2c_is_ready(mp_obj_t self_in, mp_obj_t i2c_addr_o) { mp_uint_t i2c_addr = mp_obj_get_int(i2c_addr_o); for (int i = 0; i < 10; i++) { - if (pybI2C_ScanDevice(i2c_addr, PYBI2C_TIMEOUT_TO_COUNT(PYBI2C_DEF_TIMEOUT_MS, self->baudrate))) { + if (pybI2C_ScanDevice(i2c_addr, PYBI2C_DEF_TIMEOUT_MS)) { return mp_const_true; } } @@ -397,7 +408,7 @@ STATIC mp_obj_t pyb_i2c_scan(mp_obj_t self_in) { for (uint addr = 1; addr <= 127; addr++) { for (int i = 0; i < 10; i++) { - if (pybI2C_ScanDevice(addr, PYBI2C_TIMEOUT_TO_COUNT(PYBI2C_DEF_TIMEOUT_MS, self->baudrate))) { + if (pybI2C_ScanDevice(addr, PYBI2C_DEF_TIMEOUT_MS)) { mp_obj_list_append(list, mp_obj_new_int(addr)); break; } @@ -418,7 +429,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_i2c_scan_obj, pyb_i2c_scan); STATIC const mp_arg_t pyb_i2c_send_args[] = { { MP_QSTR_send, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, { MP_QSTR_addr, MP_ARG_INT, {.u_int = 0} }, - { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5} }, + { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = PYBI2C_DEF_TIMEOUT_MS} }, }; #define PYB_I2C_SEND_NUM_ARGS MP_ARRAY_SIZE(pyb_i2c_send_args) @@ -436,8 +447,7 @@ STATIC mp_obj_t pyb_i2c_send(mp_uint_t n_args, const mp_obj_t *args, mp_map_t *k // send the data if (self->mode == PYBI2C_MODE_MASTER) { - uint timeout = MIN(PYBI2C_TIMEOUT_TO_COUNT(vals[2].u_int, self->baudrate), 255); - if (!pybI2C_Write(vals[1].u_int, bufinfo.buf, bufinfo.len, true, timeout)) { + if (!pybI2C_Write(vals[1].u_int, bufinfo.buf, bufinfo.len, true, vals[2].u_int)) { nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, mpexception_os_operation_failed)); } } else { @@ -462,7 +472,7 @@ STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_i2c_send_obj, 1, pyb_i2c_send); STATIC const mp_arg_t pyb_i2c_recv_args[] = { { MP_QSTR_recv, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, { MP_QSTR_addr, MP_ARG_INT, {.u_int = 0} }, - { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5} }, + { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = PYBI2C_DEF_TIMEOUT_MS} }, }; #define PYB_I2C_RECV_NUM_ARGS MP_ARRAY_SIZE(pyb_i2c_recv_args) @@ -479,8 +489,7 @@ STATIC mp_obj_t pyb_i2c_recv(mp_uint_t n_args, const mp_obj_t *args, mp_map_t *k // receive the data if (self->mode == PYBI2C_MODE_MASTER) { - uint timeout = MIN(PYBI2C_TIMEOUT_TO_COUNT(vals[2].u_int, self->baudrate), 255); - if (!pybI2C_Read(vals[1].u_int, (byte *)vstr.buf, vstr.len, timeout)) { + if (!pybI2C_Read(vals[1].u_int, (byte *)vstr.buf, vstr.len, vals[2].u_int)) { nlr_raise(mp_obj_new_exception_msg(&mp_type_OSError, mpexception_os_operation_failed)); } } else { @@ -512,7 +521,7 @@ STATIC const mp_arg_t pyb_i2c_mem_read_args[] = { { MP_QSTR_data, MP_ARG_REQUIRED | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} }, { MP_QSTR_addr, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} }, { MP_QSTR_memaddr, MP_ARG_REQUIRED | MP_ARG_INT, {.u_int = 0} }, - { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 5} }, + { MP_QSTR_timeout, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = PYBI2C_DEF_TIMEOUT_MS} }, { MP_QSTR_addr_size, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 8} }, }; #define PYB_I2C_MEM_READ_NUM_ARGS MP_ARRAY_SIZE(pyb_i2c_mem_read_args) @@ -539,10 +548,9 @@ STATIC mp_obj_t pyb_i2c_mem_read(mp_uint_t n_args, const mp_obj_t *args, mp_map_ mp_uint_t mem_addr_size = vals[4].u_int >> 3; // Write the register address to be read from. - uint timeout = MIN(PYBI2C_TIMEOUT_TO_COUNT(vals[3].u_int, self->baudrate), 255); - if (pybI2C_Write (i2c_addr, (byte *)&mem_addr, mem_addr_size, false, timeout)) { + if (pybI2C_Write (i2c_addr, (byte *)&mem_addr, mem_addr_size, false, vals[3].u_int)) { // Read the specified length of data - if (pybI2C_Read (i2c_addr, (byte *)vstr.buf, vstr.len, timeout)) { + if (pybI2C_Read (i2c_addr, (byte *)vstr.buf, vstr.len, vals[3].u_int)) { // return the read data if (o_ret != MP_OBJ_NULL) { return o_ret; @@ -593,10 +601,9 @@ STATIC mp_obj_t pyb_i2c_mem_write(mp_uint_t n_args, const mp_obj_t *args, mp_map mp_uint_t mem_addr_size = vals[4].u_int >> 3; // Write the register address to be write to. - uint timeout = MIN(PYBI2C_TIMEOUT_TO_COUNT(vals[2].u_int, self->baudrate), 255); - if (pybI2C_Write (i2c_addr, (byte *)&mem_addr, mem_addr_size, false, timeout)) { + if (pybI2C_Write (i2c_addr, (byte *)&mem_addr, mem_addr_size, false, vals[3].u_int)) { // Write the specified length of data - if (pybI2C_Write (i2c_addr, bufinfo.buf, bufinfo.len, true, timeout)) { + if (pybI2C_Write (i2c_addr, bufinfo.buf, bufinfo.len, true, vals[3].u_int)) { return mp_const_none; } }