/*******************************************************************************
* arch/arm/src/lpc43xx/lpc43_i2c.c
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Ported from from the LPC17 version:
*
* Copyright (C) 2011 Li Zhuoyi. All rights reserved.
* Author: Li Zhuoyi <lzyy.cn@gmail.com>
* History: 0.1 2011-08-20 initial version
*
* Derived from arch/arm/src/lpc31xx/lpc31_i2c.c
*
* Author: David Hewson
*
* Copyright (C) 2010-2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*******************************************************************************/
/*******************************************************************************
* Included Files
*******************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <nuttx/i2c.h>
#include <arch/irq.h>
#include <arch/board/board.h>
#include "wdog.h"
#include "chip.h"
#include "up_arch.h"
#include "up_internal.h"
#include "os_internal.h"
#include "lpc43_syscon.h"
#include "lpc43_pinconn.h"
#include "lpc43_i2c.h"
#if defined(CONFIG_LPC43_I2C0) || defined(CONFIG_LPC43_I2C1)
#ifndef GPIO_I2C1_SCL
#define GPIO_I2C1_SCL GPIO_I2C1_SCL_1
#define GPIO_I2C1_SDA GPIO_I2C1_SDA_1
#endif
#ifndef CONFIG_I2C0_FREQ
#define CONFIG_I2C0_FREQ 100000
#endif
#ifndef CONFIG_I2C1_FREQ
#define CONFIG_I2C1_FREQ 100000
#endif
#ifndef CONFIG_I2C2_FREQ
#define CONFIG_I2C2_FREQ 100000
#endif
/*******************************************************************************
* Definitions
*******************************************************************************/
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#define I2C_TIMEOUT ((20 * CLK_TCK) / 1000) /* 20 mS */
/****************************************************************************
* Private Data
****************************************************************************/
struct lpc43_i2cdev_s
{
struct i2c_dev_s dev; /* Generic I2C device */
struct i2c_msg_s msg; /* a single message for legacy read/write */
unsigned int base; /* Base address of registers */
uint16_t irqid; /* IRQ for this device */
sem_t mutex; /* Only one thread can access at a time */
sem_t wait; /* Place to wait for state machine completion */
volatile uint8_t state; /* State of state machine */
WDOG_ID timeout; /* watchdog to timeout when bus hung */
uint16_t wrcnt; /* number of bytes sent to tx fifo */
uint16_t rdcnt; /* number of bytes read from rx fifo */
};
#ifdef CONFIG_LPC43_I2C0
static struct lpc43_i2cdev_s g_i2c0dev;
#endif
#ifdef CONFIG_LPC43_I2C1
static struct lpc43_i2cdev_s g_i2c1dev;
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
static int i2c_start(struct lpc43_i2cdev_s *priv);
static void i2c_stop(struct lpc43_i2cdev_s *priv);
static int i2c_interrupt(int irq, FAR void *context);
static void i2c_timeout(int argc, uint32_t arg, ...);
/****************************************************************************
* I2C device operations
****************************************************************************/
static uint32_t i2c_setfrequency(FAR struct i2c_dev_s *dev,
uint32_t frequency);
static int i2c_setaddress(FAR struct i2c_dev_s *dev, int addr,
int nbits);
static int i2c_write(FAR struct i2c_dev_s *dev, const uint8_t *buffer,
int buflen);
static int i2c_read(FAR struct i2c_dev_s *dev, uint8_t *buffer,
int buflen);
static int i2c_transfer(FAR struct i2c_dev_s *dev,
FAR struct i2c_msg_s *msgs, int count);
struct i2c_ops_s lpc43_i2c_ops =
{
.setfrequency = i2c_setfrequency,
.setaddress = i2c_setaddress,
.write = i2c_write,
.read = i2c_read,
#ifdef CONFIG_I2C_TRANSFER
.transfer = i2c_transfer
#endif
};
/*******************************************************************************
* Name: lpc43_i2c_setfrequency
*
* Description:
* Set the frequence for the next transfer
*
*******************************************************************************/
static uint32_t i2c_setfrequency(FAR struct i2c_dev_s *dev, uint32_t frequency)
{
struct lpc43_i2cdev_s *priv = (struct lpc43_i2cdev_s *) dev;
if (frequency > 100000)
{
/* asymetric per 400Khz I2C spec */
putreg32(LPC43_CCLK / (83 + 47) * 47 / frequency, priv->base + LPC43_I2C_SCLH_OFFSET);
putreg32(LPC43_CCLK / (83 + 47) * 83 / frequency, priv->base + LPC43_I2C_SCLL_OFFSET);
}
else
{
/* 50/50 mark space ratio */
putreg32(LPC43_CCLK / 100 * 50 / frequency, priv->base + LPC43_I2C_SCLH_OFFSET);
putreg32(LPC43_CCLK / 100 * 50 / frequency, priv->base + LPC43_I2C_SCLL_OFFSET);
}
/* FIXME: This function should return the actual selected frequency */
return frequency;
}
/*******************************************************************************
* Name: lpc43_i2c_setaddress
*
* Description:
* Set the I2C slave address for a subsequent read/write
*
*******************************************************************************/
static int i2c_setaddress(FAR struct i2c_dev_s *dev, int addr, int nbits)
{
struct lpc43_i2cdev_s *priv = (struct lpc43_i2cdev_s *)dev;
DEBUGASSERT(dev != NULL);
DEBUGASSERT(nbits == 7);
priv->msg.addr = addr << 1;
priv->msg.flags = 0 ;
return OK;
}
/*******************************************************************************
* Name: lpc43_i2c_write
*
* Description:
* Send a block of data on I2C using the previously selected I2C
* frequency and slave address.
*
*******************************************************************************/
static int i2c_write(FAR struct i2c_dev_s *dev, const uint8_t *buffer,
int buflen)
{
struct lpc43_i2cdev_s *priv = (struct lpc43_i2cdev_s *)dev;
int ret;
DEBUGASSERT(dev != NULL);
priv->wrcnt = 0;
priv->rdcnt = 0;
priv->msg.addr &= ~0x01;
priv->msg.buffer = (uint8_t*)buffer;
priv->msg.length = buflen;
ret = i2c_start(priv);
return ret > 0 ? OK : -ETIMEDOUT;
}
/*******************************************************************************
* Name: lpc43_i2c_read
*
* Description:
* Receive a block of data on I2C using the previously selected I2C
* frequency and slave address.
*
*******************************************************************************/
static int i2c_read(FAR struct i2c_dev_s *dev, uint8_t *buffer, int buflen)
{
struct lpc43_i2cdev_s *priv = (struct lpc43_i2cdev_s *)dev;
int ret;
DEBUGASSERT(dev != NULL);
priv->wrcnt=0;
priv->rdcnt=0;
priv->msg.addr |= 0x01;
priv->msg.buffer = buffer;
priv->msg.length = buflen;
ret = i2c_start(priv);
return ret >0 ? OK : -ETIMEDOUT;
}
/*******************************************************************************
* Name: i2c_start
*
* Description:
* Perform a I2C transfer start
*
*******************************************************************************/
static int i2c_start(struct lpc43_i2cdev_s *priv)
{
int ret = -1;
sem_wait(&priv->mutex);
putreg32(I2C_CONCLR_STAC|I2C_CONCLR_SIC,priv->base+LPC43_I2C_CONCLR_OFFSET);
putreg32(I2C_CONSET_STA,priv->base+LPC43_I2C_CONSET_OFFSET);
wd_start(priv->timeout, I2C_TIMEOUT, i2c_timeout, 1, (uint32_t)priv);
sem_wait(&priv->wait);
wd_cancel(priv->timeout);
sem_post(&priv->mutex);
if (priv-> state == 0x18 || priv->state == 0x28)
{
ret = priv->wrcnt;
}
else if (priv-> state == 0x50 || priv->state == 0x58)
{
ret = priv->rdcnt;
}
return ret;
}
/*******************************************************************************
* Name: i2c_stop
*
* Description:
* Perform a I2C transfer stop
*
*******************************************************************************/
static void i2c_stop(struct lpc43_i2cdev_s *priv)
{
if (priv->state != 0x38)
{
putreg32(I2C_CONSET_STO|I2C_CONSET_AA,priv->base+LPC43_I2C_CONSET_OFFSET);
}
sem_post(&priv->wait);
}
/*******************************************************************************
* Name: i2c_timeout
*
* Description:
* Watchdog timer for timeout of I2C operation
*
*******************************************************************************/
static void i2c_timeout(int argc, uint32_t arg, ...)
{
struct lpc43_i2cdev_s *priv = (struct lpc43_i2cdev_s *)arg;
irqstate_t flags = irqsave();
priv->state = 0xff;
sem_post(&priv->wait);
irqrestore(flags);
}
/*******************************************************************************
* Name: i2c_interrupt
*
* Description:
* The I2C Interrupt Handler
*
*******************************************************************************/
static int i2c_interrupt(int irq, FAR void *context)
{
struct lpc43_i2cdev_s *priv;
uint32_t state;
#ifdef CONFIG_LPC43_I2C0
if (irq == LPC43_IRQ_I2C0)
{
priv = &g_i2c0dev;
}
else
#endif
#ifdef CONFIG_LPC43_I2C1
if (irq == LPC43_IRQ_I2C1)
{
priv = &g_i2c1dev;
}
else
#endif
{
PANIC();
}
/* Reference UM10360 19.10.5 */
state = getreg32(priv->base+LPC43_I2C_STAT_OFFSET);
putreg32(I2C_CONCLR_SIC, priv->base + LPC43_I2C_CONCLR_OFFSET);
priv->state = state;
state &= 0xf8;
switch (state)
{
case 0x00: /* Bus Error */
case 0x20:
case 0x30:
case 0x38:
case 0x48:
i2c_stop(priv);
break;
case 0x08: /* START */
case 0x10: /* Repeated START */
putreg32(priv->msg.addr, priv->base + LPC43_I2C_DAT_OFFSET);
putreg32(I2C_CONCLR_STAC, priv->base + LPC43_I2C_CONCLR_OFFSET);
break;
case 0x18:
priv->wrcnt=0;
putreg32(priv->msg.buffer[0], priv->base + LPC43_I2C_DAT_OFFSET);
break;
case 0x28:
priv->wrcnt++;
if (priv->wrcnt < priv->msg.length)
{
putreg32(priv->msg.buffer[priv->wrcnt],priv->base+LPC43_I2C_DAT_OFFSET);
}
else
{
i2c_stop(priv);
}
break;
case 0x40:
priv->rdcnt = -1;
putreg32(I2C_CONSET_AA, priv->base + LPC43_I2C_CONSET_OFFSET);
break;
case 0x50:
priv->rdcnt++;
if (priv->rdcnt < priv->msg.length)
{
priv->msg.buffer[priv->rdcnt]=getreg32(priv->base+LPC43_I2C_BUFR_OFFSET);
}
if (priv->rdcnt >= priv->msg.length - 1)
{
putreg32(I2C_CONCLR_AAC|I2C_CONCLR_SIC,priv->base+LPC43_I2C_CONCLR_OFFSET);
}
break;
case 0x58:
i2c_stop(priv);
break;
default:
i2c_stop(priv);
break;
}
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/*******************************************************************************
* Name: up_i2cinitialize
*
* Description:
* Initialise an I2C device
*
*******************************************************************************/
struct i2c_dev_s *up_i2cinitialize(int port)
{
struct lpc43_i2cdev_s *priv;
if (port>2)
{
dbg("lpc I2C Only support 0,1,2\n");
return NULL;
}
irqstate_t flags;
uint32_t regval;
flags = irqsave();
#ifdef CONFIG_LPC43_I2C0
if (port == 0)
{
priv = &g_i2c0dev;
priv->base = LPC43_I2C0_BASE;
priv->irqid = LPC43_IRQ_I2C0;
regval = getreg32(LPC43_SYSCON_PCONP);
regval |= SYSCON_PCONP_PCI2C0;
putreg32(regval, LPC43_SYSCON_PCONP);
regval = getreg32(LPC43_SYSCON_PCLKSEL0);
regval &= ~SYSCON_PCLKSEL0_I2C0_MASK;
regval |= (SYSCON_PCLKSEL_CCLK << SYSCON_PCLKSEL0_I2C0_SHIFT);
putreg32(regval, LPC43_SYSCON_PCLKSEL0);
lpc43_configgpio(GPIO_I2C0_SCL);
lpc43_configgpio(GPIO_I2C0_SDA);
putreg32(LPC43_CCLK/CONFIG_I2C0_FREQ/2, priv->base + LPC43_I2C_SCLH_OFFSET);
putreg32(LPC43_CCLK/CONFIG_I2C0_FREQ/2, priv->base + LPC43_I2C_SCLL_OFFSET);
}
else
#endif
#ifdef CONFIG_LPC43_I2C1
if (port == 1)
{
priv = &g_i2c1dev;
priv->base = LPC43_I2C1_BASE;
priv->irqid = LPC43_IRQ_I2C1;
regval = getreg32(LPC43_SYSCON_PCONP);
regval |= SYSCON_PCONP_PCI2C1;
putreg32(regval, LPC43_SYSCON_PCONP);
regval = getreg32(LPC43_SYSCON_PCLKSEL1);
regval &= ~SYSCON_PCLKSEL1_I2C1_MASK;
regval |= (SYSCON_PCLKSEL_CCLK << SYSCON_PCLKSEL1_I2C1_SHIFT);
putreg32(regval, LPC43_SYSCON_PCLKSEL1);
lpc43_configgpio(GPIO_I2C1_SCL);
lpc43_configgpio(GPIO_I2C1_SDA);
putreg32(LPC43_CCLK/CONFIG_I2C1_FREQ/2, priv->base + LPC43_I2C_SCLH_OFFSET);
putreg32(LPC43_CCLK/CONFIG_I2C1_FREQ/2, priv->base + LPC43_I2C_SCLL_OFFSET);
}
else
#endif
{
return NULL;
}
putreg32(I2C_CONSET_I2EN,priv->base+LPC43_I2C_CONSET_OFFSET);
sem_init(&priv->mutex, 0, 1);
sem_init(&priv->wait, 0, 0);
/* Allocate a watchdog timer */
priv->timeout = wd_create();
DEBUGASSERT(priv->timeout != 0);
/* Attach Interrupt Handler */
irq_attach(priv->irqid, i2c_interrupt);
/* Enable Interrupt Handler */
up_enable_irq(priv->irqid);
/* Install our operations */
priv->dev.ops = &lpc43_i2c_ops;
return &priv->dev;
}
/*******************************************************************************
* Name: up_i2cuninitalize
*
* Description:
* Uninitialise an I2C device
*
*******************************************************************************/
int up_i2cuninitialize(FAR struct i2c_dev_s * dev)
{
struct lpc43_i2cdev_s *priv = (struct lpc43_i2cdev_s *) dev;
putreg32(I2C_CONCLRT_I2ENC,priv->base+LPC43_I2C_CONCLR_OFFSET);
up_disable_irq(priv->irqid);
irq_detach(priv->irqid);
return OK;
}
#endif
