mirrors
/
pimoroni-pico
mirror of https://github.com/pimoroni/pimoroni-pico.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

VL53L5CX: Fix 32k runtime allocation in platform i2c WrMulti

This commit is contained in:
Phil Howard 2022-04-20 14:32:13 +01:00
parent 637f6d18ca
commit f79b2efa9e
1 changed files with 52 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

57
drivers/vl53l5cx/platform.c
View File

@ -104,17 +104,64 @@ uint8_t WrMulti(
uint8_t *p_values,
uint32_t size)
{
uint8_t buf[size + 2];
uint8_t buf[2];
buf[0] = RegisterAdress >> 8;
buf[1] = RegisterAdress & 0xff;
memcpy(buf + 2, p_values, size);
// Send the 16-bit address with no STOP condition
int result = i2c_write_blocking(p_platform->i2c, p_platform->address, buf, sizeof(buf), true);
if(i2c_write_blocking(p_platform->i2c, p_platform->address, buf, size + 2, false) != PICO_ERROR_GENERIC) {
return 0;
// Handle an error early... it gets dicey from here
if(result == PICO_ERROR_GENERIC) return 255;
// The VL53L5CX does not support "Repeated Start" and the Pico's I2C API doesn't
// let us send more bytes without sending another start condition.
// The horrow below lets us send out "p_values" followed by a STOP condition,
// without having to copy everything into a temporary buffer.
uint8_t *src = p_values;
// Send the rest of the data, followed by a STOP condition
// This re-implements the relevant portion of i2c_write_blocking_internal which is NOT sent a timeout check function by i2c_write_blocking
for (int byte_ctr = 0; byte_ctr < size; ++byte_ctr) {
bool last = byte_ctr == size - 1;
p_platform->i2c->hw->data_cmd =
bool_to_bit(last) << I2C_IC_DATA_CMD_STOP_LSB | *src++;
// Wait until the transmission of the address/data from the internal
// shift register has completed. For this to function correctly, the
// TX_EMPTY_CTRL flag in IC_CON must be set. The TX_EMPTY_CTRL flag
// was set in i2c_init.
do {
tight_loop_contents();
} while (!(p_platform->i2c->hw->raw_intr_stat & I2C_IC_RAW_INTR_STAT_TX_EMPTY_BITS));
if (p_platform->i2c->hw->tx_abrt_source) {
// Note clearing the abort flag also clears the reason, and
// this instance of flag is clear-on-read! Note also the
// IC_CLR_TX_ABRT register always reads as 0.
p_platform->i2c->hw->clr_tx_abrt;
// An abort on the LAST byte means things are probably fine
if(last) {
// TODO Could there be an abort while waiting for the STOP
// condition here? If so, additional code would be needed here
// to take care of the abort.
do {
tight_loop_contents();
} while (!(p_platform->i2c->hw->raw_intr_stat & I2C_IC_RAW_INTR_STAT_STOP_DET_BITS));
} else {
// Ooof, unhandled abort. Fail?
return 255;
}
}
}
return 255;
// Not sure it matters where we clear this, but by default a "nostop" style write
// will set this flag so the next transaction starts with a "Repeated Start."
p_platform->i2c->restart_on_next = false;
return 0;
}
uint8_t RdMulti(