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drivers: i2c: Add i2c master driver for Nios-II i2c core

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Add I2C Master driver for Nios-II I2C soft IP core.

This driver relies upon the Altera HAL I2C driver for all the bus level
transactions, interrupt handling and register programming.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
This commit is contained in:
Ramakrishna Pallala 2018-02-06 23:30:41 +05:30 • committed by Anas Nashif
commit 3eb62bc905
4 changed files with 207 additions and 0 deletions
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7
arch/nios2/soc/nios2f-zephyr/Kconfig.defconfig
View file

@ -25,6 +25,13 @@ config ALTERA_AVALON_QSPI
endif #SOC_FLASH_NIOS2_QSPI
if I2C_NIOS2
config ALTERA_AVALON_I2C
def_bool y
endif # I2C_NIOS2
if UART_NS16550
config UART_NS16550_PCI

1
drivers/i2c/CMakeLists.txt
View file

@ -11,6 +11,7 @@ zephyr_sources_ifdef(CONFIG_I2C_QMSI_SS i2c_qmsi_ss.c)
zephyr_sources_ifdef(CONFIG_I2C_SAM_TWI i2c_sam_twi.c)
zephyr_sources_ifdef(CONFIG_I2C_SAM_TWIHS i2c_sam_twihs.c)
zephyr_sources_ifdef(CONFIG_I2C_SBCON i2c_sbcon.c)
zephyr_sources_ifdef(CONFIG_I2C_NIOS2 i2c_nios2.c)
zephyr_sources_ifdef(CONFIG_I2C_STM32_V1
i2c_ll_stm32_v1.c

7
drivers/i2c/Kconfig
View file

@ -129,6 +129,13 @@ config I2C_BITBANG
help
Enable library used for software driven (bit banging) I2C support
config I2C_NIOS2
bool "Nios-II I2C driver"
depends on HAS_ALTERA_HAL
default n
help
Enable the Nios-II I2C driver.
source "drivers/i2c/Kconfig.sbcon"
source "drivers/i2c/Kconfig.gpio"

192
drivers/i2c/i2c_nios2.c Normal file
View file

@ -0,0 +1,192 @@
/*
* Copyright (c) 2018 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <errno.h>
#include <i2c.h>
#include <soc.h>
#include <misc/util.h>
#include <logging/sys_log.h>
#include <altera_common.h>
#include "altera_avalon_i2c.h"
#define NIOS2_I2C_TIMEOUT_USEC 1000
#define DEV_CFG(dev) \
((struct i2c_nios2_config *)(dev)->config->config_info)
struct i2c_nios2_config {
ALT_AVALON_I2C_DEV_t i2c_dev;
IRQ_DATA_t irq_data;
struct k_sem sem_lock;
};
static int i2c_nios2_configure(struct device *dev, u32_t dev_config)
{
struct i2c_nios2_config *config = DEV_CFG(dev);
s32_t rc = 0;
k_sem_take(&config->sem_lock, K_FOREVER);
if (!(I2C_MODE_MASTER & dev_config)) {
SYS_LOG_ERR("i2c config mode error\n");
rc = -EINVAL;
goto i2c_cfg_err;
}
if (I2C_ADDR_10_BITS & dev_config) {
SYS_LOG_ERR("i2c config addresing error\n");
rc = -EINVAL;
goto i2c_cfg_err;
}
if (I2C_SPEED_GET(dev_config) != I2C_SPEED_STANDARD) {
SYS_LOG_ERR("i2c config speed error\n");
rc = -EINVAL;
goto i2c_cfg_err;
}
alt_avalon_i2c_init(&config->i2c_dev);
i2c_cfg_err:
k_sem_give(&config->sem_lock);
return rc;
}
static int i2c_nios2_transfer(struct device *dev, struct i2c_msg *msgs,
u8_t num_msgs, u16_t addr)
{
struct i2c_nios2_config *config = DEV_CFG(dev);
ALT_AVALON_I2C_STATUS_CODE status;
u32_t restart, stop;
s32_t i, timeout, rc = 0;
k_sem_take(&config->sem_lock, K_FOREVER);
/* register the optional interrupt callback */
alt_avalon_i2c_register_optional_irq_handler(
&config->i2c_dev, &config->irq_data);
/* Iterate over all the messages */
for (i = 0; i < num_msgs; i++) {
/* convert restart flag */
if (msgs->flags & I2C_MSG_RESTART) {
restart = ALT_AVALON_I2C_RESTART;
} else {
restart = ALT_AVALON_I2C_NO_RESTART;
}
/* convert stop flag */
if (msgs->flags & I2C_MSG_STOP) {
stop = ALT_AVALON_I2C_STOP;
} else {
stop = ALT_AVALON_I2C_NO_STOP;
}
/* Set the slave device address */
alt_avalon_i2c_master_target_set(&config->i2c_dev, addr);
/* Start the transfer */
if (msgs->flags & I2C_MSG_READ) {
status = alt_avalon_i2c_master_receive_using_interrupts(
&config->i2c_dev,
msgs->buf, msgs->len,
restart, stop);
} else {
status = alt_avalon_i2c_master_transmit_using_interrupts
(&config->i2c_dev,
msgs->buf, msgs->len,
restart, stop);
}
/* Return an error if the transfer didn't
* start successfully e.g., if the bus was busy
*/
if (status != ALT_AVALON_I2C_SUCCESS) {
SYS_LOG_ERR("i2c transfer error %d\n", status);
rc = -EIO;
goto i2c_transfer_err;
}
timeout = NIOS2_I2C_TIMEOUT_USEC;
while (timeout) {
k_busy_wait(1);
status = alt_avalon_i2c_interrupt_transaction_status(
&config->i2c_dev);
if (status == ALT_AVALON_I2C_SUCCESS) {
break;
}
timeout--;
}
if (timeout <= 0) {
SYS_LOG_ERR("i2c busy or timeout error %d\n", status);
rc = -EIO;
goto i2c_transfer_err;
}
/* move to the next message */
msgs++;
}
i2c_transfer_err:
alt_avalon_i2c_disable(&config->i2c_dev);
k_sem_give(&config->sem_lock);
return rc;
}
static void i2c_nios2_isr(void *arg)
{
struct device *dev = (struct device *)arg;
struct i2c_nios2_config *config = DEV_CFG(dev);
/* Call Altera HAL driver ISR */
alt_handle_irq(&config->i2c_dev, I2C_0_IRQ);
}
static int i2c_nios2_init(struct device *dev);
static struct i2c_driver_api i2c_nios2_driver_api = {
.configure = i2c_nios2_configure,
.transfer = i2c_nios2_transfer,
};
static struct i2c_nios2_config i2c_nios2_cfg = {
.i2c_dev = {
.i2c_base = (alt_u32 *)I2C_0_BASE,
.irq_controller_ID = I2C_0_IRQ_INTERRUPT_CONTROLLER_ID,
.irq_ID = I2C_0_IRQ,
.ip_freq_in_hz = I2C_0_FREQ,
},
};
DEVICE_AND_API_INIT(i2c_nios2_0, CONFIG_I2C_0_NAME, &i2c_nios2_init,
NULL, &i2c_nios2_cfg,
POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE,
&i2c_nios2_driver_api);
static int i2c_nios2_init(struct device *dev)
{
struct i2c_nios2_config *config = DEV_CFG(dev);
int rc;
/* initialize semaphore */
k_sem_init(&config->sem_lock, 1, 1);
rc = i2c_nios2_configure(dev,
I2C_MODE_MASTER |
I2C_SPEED_SET(I2C_SPEED_STANDARD));
if (rc) {
SYS_LOG_ERR("i2c configure failed %d\n", rc);
return rc;
}
/* clear ISR register content */
alt_avalon_i2c_int_clear(&config->i2c_dev,
ALT_AVALON_I2C_ISR_ALL_CLEARABLE_INTS_MSK);
IRQ_CONNECT(I2C_0_IRQ, CONFIG_I2C_0_IRQ_PRI,
i2c_nios2_isr, DEVICE_GET(i2c_nios2_0), 0);
irq_enable(I2C_0_IRQ);
return 0;
}