riot-ci/RIOT
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Merge pull request #16711 from nicoHarel/cpu/nrf52/periph/i2c

Browse Source 
cpu/nrf52: i2c: add support for 16-bit register addresses
This commit is contained in:
benpicco 2021-08-06 16:55:53 +02:00 committed by GitHub
commit 8c7db062af
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 56 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

70
cpu/nrf52/periph/i2c.c
View File

@ -31,6 +31,7 @@
#include "assert.h"
#include "periph/i2c.h"
#include "periph/gpio.h"
#include "byteorder.h"
#define ENABLE_DEBUG 0
#include "debug.h"
@ -40,6 +41,16 @@
*/
#define INVALID_SPEED_MASK (0xff)
/**
* @brief Allocate a tx buffer
*/
static uint8_t tx_buf[256];
/**
* @brief Mutex for locking the TX buffer
*/
static mutex_t buffer_lock;
/**
* @brief Initialized dev locks (we have a maximum of two devices...)
*/
@ -167,21 +178,41 @@ void i2c_release(i2c_t dev)
int i2c_write_regs(i2c_t dev, uint16_t addr, uint16_t reg,
const void *data, size_t len, uint8_t flags)
{
assert((dev < I2C_NUMOF) && data && (len > 0) && (len < 255));
assert((dev < I2C_NUMOF) && data && (len > 0) && (len < 253));
if (flags & (I2C_NOSTART | I2C_REG16 | I2C_ADDR10)) {
if (flags & (I2C_NOSTART | I2C_ADDR10)) {
return -EOPNOTSUPP;
}
/* the nrf52's TWI device does not support to do two consecutive transfers
* without a repeated start condition in between. So we have to put all data
* to be transferred into a temporary buffer
*
* CAUTION: this might become critical when transferring large blocks of
* data as the temporary buffer is allocated on the stack... */
uint8_t buf_tmp[len + 1];
buf_tmp[0] = reg;
memcpy(&buf_tmp[1], data, len);
return i2c_write_bytes(dev, addr, buf_tmp, (len + 1), flags);
* to be transferred into a buffer (tx_buf).
* */
uint8_t reg_addr_len; /* Length in bytes of the register address */
/* Lock tx_buf */
mutex_lock(&buffer_lock);
if (flags & (I2C_REG16)) {
reg_addr_len = 2;
/* Prepare the 16-bit register transfer */
tx_buf[0] = reg >> 8; /* AddrH in the first byte */
tx_buf[1] = reg & 0xFF; /* AddrL in the second byte */
}
else{
reg_addr_len = 1;
tx_buf[0] = reg;
}
memcpy(&tx_buf[reg_addr_len], data, len);
int ret = i2c_write_bytes(dev, addr, tx_buf, reg_addr_len + len, flags);
/* Release tx_buf */
mutex_unlock(&buffer_lock);
return ret;
}
int i2c_read_bytes(i2c_t dev, uint16_t addr, void *data, size_t len,
@ -189,7 +220,7 @@ int i2c_read_bytes(i2c_t dev, uint16_t addr, void *data, size_t len,
{
assert((dev < I2C_NUMOF) && data && (len > 0) && (len < 256));
if (flags & (I2C_NOSTART | I2C_REG16 | I2C_ADDR10)) {
if (flags & (I2C_NOSTART | I2C_ADDR10)) {
return -EOPNOTSUPP;
}
DEBUG("[i2c] read_bytes: %i bytes from addr 0x%02x\n", (int)len, (int)addr);
@ -212,21 +243,32 @@ int i2c_read_regs(i2c_t dev, uint16_t addr, uint16_t reg,
{
assert((dev < I2C_NUMOF) && data && (len > 0) && (len < 256));
if (flags & (I2C_NOSTART | I2C_REG16 | I2C_ADDR10)) {
if (flags & (I2C_NOSTART | I2C_ADDR10)) {
return -EOPNOTSUPP;
}
DEBUG("[i2c] read_regs: %i byte(s) from reg 0x%02x at addr 0x%02x\n",
(int)len, (int)reg, (int)addr);
/* Prepare transfer */
bus(dev)->ADDRESS = addr;
if (flags & (I2C_REG16)) {
/* Register endianness for 16 bit */
reg = htons(reg);
bus(dev)->TXD.MAXCNT = 2;
}
else {
bus(dev)->TXD.MAXCNT = 1;
}
bus(dev)->TXD.PTR = (uint32_t)&reg;
bus(dev)->TXD.MAXCNT = 1;
bus(dev)->RXD.PTR = (uint32_t)data;
bus(dev)->RXD.MAXCNT = (uint8_t)len;
bus(dev)->SHORTS = (TWIM_SHORTS_LASTTX_STARTRX_Msk);
if (!(flags & I2C_NOSTOP)) {
bus(dev)->SHORTS |= TWIM_SHORTS_LASTRX_STOP_Msk;
}
/* Start transfer */
bus(dev)->TASKS_STARTTX = 1;
return finish(dev);
@ -237,7 +279,7 @@ int i2c_write_bytes(i2c_t dev, uint16_t addr, const void *data, size_t len,
{
assert((dev < I2C_NUMOF) && data && (len > 0) && (len < 256));
if (flags & (I2C_NOSTART | I2C_REG16 | I2C_ADDR10)) {
if (flags & (I2C_NOSTART | I2C_ADDR10)) {
return -EOPNOTSUPP;
}
DEBUG("[i2c] write_bytes: %i byte(s) to addr 0x%02x\n", (int)len, (int)addr);