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author | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2012-09-17 18:18:44 +0000 |
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committer | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2012-09-17 18:18:44 +0000 |
commit | 57623d42ebb04f0a0b9e6eb7c0847a3ece2aa0ff (patch) | |
tree | 25d07d14e920d31c0b1947c9ca586f2a01fc32d8 /nuttx/arch/arm/src/stm32/stm32_i2c.c | |
download | px4-firmware-57623d42ebb04f0a0b9e6eb7c0847a3ece2aa0ff.tar.gz px4-firmware-57623d42ebb04f0a0b9e6eb7c0847a3ece2aa0ff.tar.bz2 px4-firmware-57623d42ebb04f0a0b9e6eb7c0847a3ece2aa0ff.zip |
Resync new repository with old repo r5166
git-svn-id: http://svn.code.sf.net/p/nuttx/code/trunk@5153 42af7a65-404d-4744-a932-0658087f49c3
Diffstat (limited to 'nuttx/arch/arm/src/stm32/stm32_i2c.c')
-rw-r--r-- | nuttx/arch/arm/src/stm32/stm32_i2c.c | 1917 |
1 files changed, 1917 insertions, 0 deletions
diff --git a/nuttx/arch/arm/src/stm32/stm32_i2c.c b/nuttx/arch/arm/src/stm32/stm32_i2c.c new file mode 100644 index 000000000..cbd6f6b14 --- /dev/null +++ b/nuttx/arch/arm/src/stm32/stm32_i2c.c @@ -0,0 +1,1917 @@ +/************************************************************************************ + * arch/arm/src/stm32/stm32_i2c.c + * STM32 I2C Hardware Layer - Device Driver + * + * Copyright (C) 2011 Uros Platise. All rights reserved. + * Author: Uros Platise <uros.platise@isotel.eu> + * + * With extensions, modifications by: + * + * Copyright (C) 2011-2012 Gregory Nutt. All rights reserved. + * Author: Gregroy 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. + * + ************************************************************************************/ + +/* Supports: + * - Master operation, 100 kHz (standard) and 400 kHz (full speed) + * - Multiple instances (shared bus) + * - Interrupt based operation + * + * Structure naming: + * - Device: structure as defined by the nuttx/i2c/i2c.h + * - Instance: represents each individual access to the I2C driver, obtained by + * the i2c_init(); it extends the Device structure from the nuttx/i2c/i2c.h; + * Instance points to OPS, to common I2C Hardware private data and contains + * its own private data, as frequency, address, mode of operation (in the future) + * - Private: Private data of an I2C Hardware + * + * TODO + * - Check for all possible deadlocks (as BUSY='1' I2C needs to be reset in HW using the I2C_CR1_SWRST) + * - SMBus support (hardware layer timings are already supported) and add SMBA gpio pin + * - Slave support with multiple addresses (on multiple instances): + * - 2 x 7-bit address or + * - 1 x 10 bit adresses + 1 x 7 bit address (?) + * - plus the broadcast address (general call) + * - Multi-master support + * - DMA (to get rid of too many CPU wake-ups and interventions) + * - Be ready for IPMI + */ + +/************************************************************************************ + * Included Files + ************************************************************************************/ + +#include <nuttx/config.h> + +#include <sys/types.h> +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <stdbool.h> +#include <semaphore.h> +#include <errno.h> +#include <debug.h> + +#include <nuttx/arch.h> +#include <nuttx/irq.h> +#include <nuttx/i2c.h> +#include <nuttx/kmalloc.h> +#include <nuttx/clock.h> + +#include <arch/board/board.h> + +#include "up_arch.h" + +#include "stm32_rcc.h" +#include "stm32_i2c.h" +#include "stm32_waste.h" + +#if defined(CONFIG_STM32_I2C1) || defined(CONFIG_STM32_I2C2) || defined(CONFIG_STM32_I2C3) + +/************************************************************************************ + * Pre-processor Definitions + ************************************************************************************/ +/* Configuration ********************************************************************/ +/* CONFIG_I2C_POLLED may be set so that I2C interrrupts will not be used. Instead, + * CPU-intensive polling will be used. + */ + +/* Interrupt wait timeout in seconds and milliseconds */ + +#if !defined(CONFIG_STM32_I2CTIMEOSEC) && !defined(CONFIG_STM32_I2CTIMEOMS) +# define CONFIG_STM32_I2CTIMEOSEC 0 +# define CONFIG_STM32_I2CTIMEOMS 500 /* Default is 500 milliseconds */ +#elif !defined(CONFIG_STM32_I2CTIMEOSEC) +# define CONFIG_STM32_I2CTIMEOSEC 0 /* User provided milliseconds */ +#elif !defined(CONFIG_STM32_I2CTIMEOMS) +# define CONFIG_STM32_I2CTIMEOMS 0 /* User provided seconds */ +#endif + +/* Interrupt wait time timeout in system timer ticks */ + +#define CONFIG_STM32_I2CTIMEOTICKS \ + (SEC2TICK(CONFIG_STM32_I2CTIMEOSEC) + MSEC2TICK(CONFIG_STM32_I2CTIMEOMS)) + +/* On the STM32F103ZE, there is an internal conflict between I2C1 and FSMC. In that + * case, it is necessary to disable FSMC before each I2C1 access and re-enable FSMC + * when the I2C access completes. + */ + +#undef I2C1_FSMC_CONFLICT +#if defined(CONFIG_STM32_STM32F10XX) && defined(CONFIG_STM32_FSMC) && defined(CONFIG_STM32_I2C1) +# define I2C1_FSMC_CONFLICT +#endif + +/* Debug ****************************************************************************/ +/* CONFIG_DEBUG_I2C + CONFIG_DEBUG enables general I2C debug output. */ + +#ifdef CONFIG_DEBUG_I2C +# define i2cdbg dbg +# define i2cvdbg vdbg +#else +# define i2cdbg(x...) +# define i2cvdbg(x...) +#endif + +/* I2C event trace logic. NOTE: trace uses the internal, non-standard, low-level + * debug interface lib_rawprintf() but does not require that any other debug + * is enabled. + */ + +#ifndef CONFIG_I2C_TRACE +# define stm32_i2c_tracereset(p) +# define stm32_i2c_tracenew(p,s) +# define stm32_i2c_traceevent(p,e,a) +# define stm32_i2c_tracedump(p) +#endif + +#ifndef CONFIG_I2C_NTRACE +# define CONFIG_I2C_NTRACE 32 +#endif + +/************************************************************************************ + * Private Types + ************************************************************************************/ +/* Interrupt state */ + +enum stm32_intstate_e +{ + INTSTATE_IDLE = 0, /* No I2C activity */ + INTSTATE_WAITING, /* Waiting for completion of interrupt activity */ + INTSTATE_DONE, /* Interrupt activity complete */ +}; + +/* Trace events */ + +enum stm32_trace_e +{ + I2CEVENT_NONE = 0, /* No events have occurred with this status */ + I2CEVENT_SENDADDR, /* Start/Master bit set and address sent, param = msgc */ + I2CEVENT_SENDBYTE, /* Send byte, param = dcnt */ + I2CEVENT_ITBUFEN, /* Enable buffer interrupts, param = 0 */ + I2CEVENT_RCVBYTE, /* Read more dta, param = dcnt */ + I2CEVENT_REITBUFEN, /* Re-enable buffer interrupts, param = 0 */ + I2CEVENT_DISITBUFEN, /* Disable buffer interrupts, param = 0 */ + I2CEVENT_BTFNOSTART, /* BTF on last byte with no restart, param = msgc */ + I2CEVENT_BTFRESTART, /* Last byte sent, re-starting, param = msgc */ + I2CEVENT_BTFSTOP, /* Last byte sten, send stop, param = 0 */ + I2CEVENT_ERROR /* Error occurred, param = 0 */ +}; + +/* Trace data */ + +struct stm32_trace_s +{ + uint32_t status; /* I2C 32-bit SR2|SR1 status */ + uint32_t count; /* Interrupt count when status change */ + enum stm32_intstate_e event; /* Last event that occurred with this status */ + uint32_t parm; /* Parameter associated with the event */ + uint32_t time; /* First of event or first status */ +}; + +/* I2C Device Private Data */ + +struct stm32_i2c_priv_s +{ + uint32_t base; /* I2C base address */ + int refs; /* Referernce count */ + sem_t sem_excl; /* Mutual exclusion semaphore */ +#ifndef CONFIG_I2C_POLLED + sem_t sem_isr; /* Interrupt wait semaphore */ +#endif + volatile uint8_t intstate; /* Interrupt handshake (see enum stm32_intstate_e) */ + + uint8_t msgc; /* Message count */ + struct i2c_msg_s *msgv; /* Message list */ + uint8_t *ptr; /* Current message buffer */ + int dcnt; /* Current message length */ + uint16_t flags; /* Current message flags */ + + /* I2C trace support */ + +#ifdef CONFIG_I2C_TRACE + int tndx; /* Trace array index */ + uint32_t start_time; /* Time when the trace was started */ + + /* The actual trace data */ + + struct stm32_trace_s trace[CONFIG_I2C_NTRACE]; +#endif + + uint32_t status; /* End of transfer SR2|SR1 status */ +}; + +/* I2C Device, Instance */ + +struct stm32_i2c_inst_s +{ + struct i2c_ops_s *ops; /* Standard I2C operations */ + struct stm32_i2c_priv_s *priv; /* Common driver private data structure */ + + uint32_t frequency; /* Frequency used in this instantiation */ + int address; /* Address used in this instantiation */ + uint16_t flags; /* Flags used in this instantiation */ +}; + +/************************************************************************************ + * Private Function Prototypes + ************************************************************************************/ + +static inline uint16_t stm32_i2c_getreg(FAR struct stm32_i2c_priv_s *priv, + uint8_t offset); +static inline void stm32_i2c_putreg(FAR struct stm32_i2c_priv_s *priv, uint8_t offset, + uint16_t value); +static inline void stm32_i2c_modifyreg(FAR struct stm32_i2c_priv_s *priv, + uint8_t offset, uint16_t clearbits, + uint16_t setbits); +static inline void stm32_i2c_sem_wait(FAR struct i2c_dev_s *dev); +static inline int stm32_i2c_sem_waitdone(FAR struct stm32_i2c_priv_s *priv); +static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv); +static inline void stm32_i2c_sem_post(FAR struct i2c_dev_s *dev); +static inline void stm32_i2c_sem_init(FAR struct i2c_dev_s *dev); +static inline void stm32_i2c_sem_destroy(FAR struct i2c_dev_s *dev); +#ifdef CONFIG_I2C_TRACE +static void stm32_i2c_tracereset(FAR struct stm32_i2c_priv_s *priv); +static void stm32_i2c_tracenew(FAR struct stm32_i2c_priv_s *priv, uint32_t status); +static void stm32_i2c_traceevent(FAR struct stm32_i2c_priv_s *priv, + enum stm32_trace_e event, uint32_t parm); +static void stm32_i2c_tracedump(FAR struct stm32_i2c_priv_s *priv); +#endif +static void stm32_i2c_setclock(FAR struct stm32_i2c_priv_s *priv, + uint32_t frequency); +static inline void stm32_i2c_sendstart(FAR struct stm32_i2c_priv_s *priv); +static inline void stm32_i2c_clrstart(FAR struct stm32_i2c_priv_s *priv); +static inline void stm32_i2c_sendstop(FAR struct stm32_i2c_priv_s *priv); +static inline uint32_t stm32_i2c_getstatus(FAR struct stm32_i2c_priv_s *priv); +#ifdef I2C1_FSMC_CONFLICT +static inline uint32_t stm32_i2c_disablefsmc(FAR struct stm32_i2c_priv_s *priv); +static inline void stm32_i2c_enablefsmc(uint32_t ahbenr); +#endif +static int stm32_i2c_isr(struct stm32_i2c_priv_s * priv); +#ifndef CONFIG_I2C_POLLED +#ifdef CONFIG_STM32_I2C1 +static int stm32_i2c1_isr(int irq, void *context); +#endif +#ifdef CONFIG_STM32_I2C2 +static int stm32_i2c2_isr(int irq, void *context); +#endif +#ifdef CONFIG_STM32_I2C3 +static int stm32_i2c3_isr(int irq, void *context); +#endif +#endif +static int stm32_i2c_init(FAR struct stm32_i2c_priv_s *priv); +static int stm32_i2c_deinit(FAR struct stm32_i2c_priv_s *priv); +static uint32_t stm32_i2c_setfrequency(FAR struct i2c_dev_s *dev, + uint32_t frequency); +static int stm32_i2c_setaddress(FAR struct i2c_dev_s *dev, int addr, int nbits); +static int stm32_i2c_process(FAR struct i2c_dev_s *dev, FAR struct i2c_msg_s *msgs, + int count); +static int stm32_i2c_write(FAR struct i2c_dev_s *dev, const uint8_t *buffer, + int buflen); +static int stm32_i2c_read(FAR struct i2c_dev_s *dev, uint8_t *buffer, int buflen); +#ifdef CONFIG_I2C_WRITEREAD +static int stm32_i2c_writeread(FAR struct i2c_dev_s *dev, + const uint8_t *wbuffer, int wbuflen, + uint8_t *buffer, int buflen); +#endif +#ifdef CONFIG_I2C_TRANSFER +static int stm32_i2c_transfer(FAR struct i2c_dev_s *dev, FAR struct i2c_msg_s *msgs, + int count); +#endif + +/************************************************************************************ + * Private Data + ************************************************************************************/ + +#ifdef CONFIG_STM32_I2C1 +struct stm32_i2c_priv_s stm32_i2c1_priv = +{ + .base = STM32_I2C1_BASE, + .refs = 0, + .intstate = INTSTATE_IDLE, + .msgc = 0, + .msgv = NULL, + .ptr = NULL, + .dcnt = 0, + .flags = 0, + .status = 0 +}; +#endif + +#ifdef CONFIG_STM32_I2C2 +struct stm32_i2c_priv_s stm32_i2c2_priv = +{ + .base = STM32_I2C2_BASE, + .refs = 0, + .intstate = INTSTATE_IDLE, + .msgc = 0, + .msgv = NULL, + .ptr = NULL, + .dcnt = 0, + .flags = 0, + .status = 0 +}; +#endif + +#ifdef CONFIG_STM32_I2C3 +struct stm32_i2c_priv_s stm32_i2c3_priv = +{ + .base = STM32_I2C3_BASE, + .refs = 0, + .intstate = INTSTATE_IDLE, + .msgc = 0, + .msgv = NULL, + .ptr = NULL, + .dcnt = 0, + .flags = 0, + .status = 0 +}; +#endif + + +/* Device Structures, Instantiation */ + +struct i2c_ops_s stm32_i2c_ops = +{ + .setfrequency = stm32_i2c_setfrequency, + .setaddress = stm32_i2c_setaddress, + .write = stm32_i2c_write, + .read = stm32_i2c_read +#ifdef CONFIG_I2C_WRITEREAD + , .writeread = stm32_i2c_writeread +#endif +#ifdef CONFIG_I2C_TRANSFER + , .transfer = stm32_i2c_transfer +#endif +#ifdef CONFIG_I2C_SLAVE + , .setownaddress = stm32_i2c_setownaddress, + .registercallback = stm32_i2c_registercallback +#endif +}; + +/************************************************************************************ + * Private Functions + ************************************************************************************/ + +/************************************************************************************ + * Name: stm32_i2c_getreg + * + * Description: + * Get register value by offset + * + ************************************************************************************/ + +static inline uint16_t stm32_i2c_getreg(FAR struct stm32_i2c_priv_s *priv, + uint8_t offset) +{ + return getreg16(priv->base + offset); +} + +/************************************************************************************ + * Name: stm32_i2c_putreg + * + * Description: + * Put register value by offset + * + ************************************************************************************/ + +static inline void stm32_i2c_putreg(FAR struct stm32_i2c_priv_s *priv, uint8_t offset, + uint16_t value) +{ + putreg16(value, priv->base + offset); +} + +/************************************************************************************ + * Name: stm32_i2c_modifyreg + * + * Description: + * Modify register value by offset + * + ************************************************************************************/ + +static inline void stm32_i2c_modifyreg(FAR struct stm32_i2c_priv_s *priv, + uint8_t offset, uint16_t clearbits, + uint16_t setbits) +{ + modifyreg16(priv->base + offset, clearbits, setbits); +} + +/************************************************************************************ + * Name: + * + * Description: + * + * + ************************************************************************************/ + +static inline void stm32_i2c_sem_wait(FAR struct i2c_dev_s *dev) +{ + while (sem_wait(&((struct stm32_i2c_inst_s *)dev)->priv->sem_excl) != 0) + { + ASSERT(errno == EINTR); + } +} + +/************************************************************************************ + * Name: stm32_i2c_sem_waitdone + * + * Description: + * Wait for a transfer to complete + * + ************************************************************************************/ + +#ifndef CONFIG_I2C_POLLED +static inline int stm32_i2c_sem_waitdone(FAR struct stm32_i2c_priv_s *priv) +{ + struct timespec abstime; + irqstate_t flags; + uint32_t regval; + int ret; + + flags = irqsave(); + + /* Enable I2C interrupts */ + + regval = stm32_i2c_getreg(priv, STM32_I2C_CR2_OFFSET); + regval |= (I2C_CR2_ITERREN | I2C_CR2_ITEVFEN); + stm32_i2c_putreg(priv, STM32_I2C_CR2_OFFSET, regval); + + /* Signal the interrupt handler that we are waiting. NOTE: Interrupts + * are currently disabled but will be temporarily re-enabled below when + * sem_timedwait() sleeps. + */ + + priv->intstate = INTSTATE_WAITING; + do + { + /* Get the current time */ + + (void)clock_gettime(CLOCK_REALTIME, &abstime); + + /* Calculate a time in the future */ + +#if CONFIG_STM32_I2CTIMEOSEC > 0 + abstime.tv_sec += CONFIG_STM32_I2CTIMEOSEC; +#endif +#if CONFIG_STM32_I2CTIMEOMS > 0 + abstime.tv_nsec += CONFIG_STM32_I2CTIMEOMS * 1000 * 1000; + if (abstime.tv_nsec > 1000 * 1000 * 1000) + { + abstime.tv_sec++; + abstime.tv_nsec -= 1000 * 1000 * 1000; + } +#endif + /* Wait until either the transfer is complete or the timeout expires */ + + ret = sem_timedwait(&priv->sem_isr, &abstime); + if (ret != OK && errno != EINTR) + { + /* Break out of the loop on irrecoverable errors. This would + * include timeouts and mystery errors reported by sem_timedwait. + * NOTE that we try again if we are awakened by a signal (EINTR). + */ + + break; + } + } + + /* Loop until the interrupt level transfer is complete. */ + + while (priv->intstate != INTSTATE_DONE); + + /* Set the interrupt state back to IDLE */ + + priv->intstate = INTSTATE_IDLE; + + /* Disable I2C interrupts */ + + regval = stm32_i2c_getreg(priv, STM32_I2C_CR2_OFFSET); + regval &= ~I2C_CR2_ALLINTS; + stm32_i2c_putreg(priv, STM32_I2C_CR2_OFFSET, regval); + + irqrestore(flags); + return ret; +} +#else +static inline int stm32_i2c_sem_waitdone(FAR struct stm32_i2c_priv_s *priv ) +{ + uint32_t start; + uint32_t elapsed; + int ret; + + /* Signal the interrupt handler that we are waiting. NOTE: Interrupts + * are currently disabled but will be temporarily re-enabled below when + * sem_timedwait() sleeps. + */ + + priv->intstate = INTSTATE_WAITING; + start = clock_systimer(); + do + { + /* Poll by simply calling the timer interrupt handler until it + * reports that it is done. + */ + + stm32_i2c_isr(priv); + + /* Calculate the elapsed time */ + + elapsed = clock_systimer() - start; + } + + /* Loop until the transfer is complete. */ + + while (priv->intstate != INTSTATE_DONE && elapsed < CONFIG_STM32_I2CTIMEOTICKS); + + i2cvdbg("intstate: %d elapsed: %d threshold: %d status: %08x\n", + priv->intstate, elapsed, CONFIG_STM32_I2CTIMEOTICKS, priv->status); + + /* Set the interrupt state back to IDLE */ + + ret = priv->intstate == INTSTATE_DONE ? OK : -ETIMEDOUT; + priv->intstate = INTSTATE_IDLE; + return ret; +} +#endif + +/************************************************************************************ + * Name: stm32_i2c_sem_waitstop + * + * Description: + * Wait for a STOP to complete + * + ************************************************************************************/ + +static inline void stm32_i2c_sem_waitstop(FAR struct stm32_i2c_priv_s *priv) +{ + uint32_t start; + uint32_t elapsed; + uint32_t cr1; + uint32_t sr1; + + /* Wait as stop might still be in progress; but stop might also + * be set because of a timeout error: "The [STOP] bit is set and + * cleared by software, cleared by hardware when a Stop condition is + * detected, set by hardware when a timeout error is detected." + */ + + start = clock_systimer(); + do + { + /* Check for STOP condition */ + + cr1 = stm32_i2c_getreg(priv, STM32_I2C_CR1_OFFSET); + if ((cr1 & I2C_CR1_STOP) == 0) + { + return; + } + + /* Check for timeout error */ + + sr1 = stm32_i2c_getreg(priv, STM32_I2C_SR1_OFFSET); + if ((sr1 & I2C_SR1_TIMEOUT) != 0) + { + return; + } + + /* Calculate the elapsed time */ + + elapsed = clock_systimer() - start; + } + + /* Loop until the stop is complete or a timeout occurs. */ + + while (elapsed < CONFIG_STM32_I2CTIMEOTICKS); + + /* If we get here then a timeout occurred with the STOP condition + * still pending. + */ + + i2cvdbg("Timeout with CR1: %04x SR1: %04x\n", cr1, sr1); +} + +/************************************************************************************ + * Name: stm32_i2c_sem_post + * + * Description: + * Release the mutual exclusion semaphore + * + ************************************************************************************/ + +static inline void stm32_i2c_sem_post(FAR struct i2c_dev_s *dev) +{ + sem_post( &((struct stm32_i2c_inst_s *)dev)->priv->sem_excl ); +} + +/************************************************************************************ + * Name: stm32_i2c_sem_init + * + * Description: + * Initialize semaphores + * + ************************************************************************************/ + +static inline void stm32_i2c_sem_init(FAR struct i2c_dev_s *dev) +{ + sem_init(&((struct stm32_i2c_inst_s *)dev)->priv->sem_excl, 0, 1); +#ifndef CONFIG_I2C_POLLED + sem_init(&((struct stm32_i2c_inst_s *)dev)->priv->sem_isr, 0, 0); +#endif +} + +/************************************************************************************ + * Name: stm32_i2c_sem_destroy + * + * Description: + * Destroy semaphores. + * + ************************************************************************************/ + +static inline void stm32_i2c_sem_destroy(FAR struct i2c_dev_s *dev) +{ + sem_destroy(&((struct stm32_i2c_inst_s *)dev)->priv->sem_excl); +#ifndef CONFIG_I2C_POLLED + sem_destroy(&((struct stm32_i2c_inst_s *)dev)->priv->sem_isr); +#endif +} + +/************************************************************************************ + * Name: stm32_i2c_trace* + * + * Description: + * I2C trace instrumentation + * + ************************************************************************************/ + +#ifdef CONFIG_I2C_TRACE +static void stm32_i2c_traceclear(FAR struct stm32_i2c_priv_s *priv) +{ + struct stm32_trace_s *trace = &priv->trace[priv->tndx]; + + trace->status = 0; /* I2C 32-bit SR2|SR1 status */ + trace->count = 0; /* Interrupt count when status change */ + trace->event = I2CEVENT_NONE; /* Last event that occurred with this status */ + trace->parm = 0; /* Parameter associated with the event */ + trace->time = 0; /* Time of first status or event */ +} + +static void stm32_i2c_tracereset(FAR struct stm32_i2c_priv_s *priv) +{ + /* Reset the trace info for a new data collection */ + + priv->tndx = 0; + priv->start_time = clock_systimer(); + stm32_i2c_traceclear(priv); +} + +static void stm32_i2c_tracenew(FAR struct stm32_i2c_priv_s *priv, uint32_t status) +{ + struct stm32_trace_s *trace = &priv->trace[priv->tndx]; + + /* Is the current entry uninitialized? Has the status changed? */ + + if (trace->count == 0 || status != trace->status) + { + /* Yes.. Was it the status changed? */ + + if (trace->count != 0) + { + /* Yes.. bump up the trace index (unless we are out of trace entries) */ + + if (priv->tndx >= (CONFIG_I2C_NTRACE-1)) + { + i2cdbg("Trace table overflow\n"); + return; + } + + priv->tndx++; + trace = &priv->trace[priv->tndx]; + } + + /* Initialize the new trace entry */ + + stm32_i2c_traceclear(priv); + trace->status = status; + trace->count = 1; + trace->time = clock_systimer(); + } + else + { + /* Just increment the count of times that we have seen this status */ + + trace->count++; + } +} + +static void stm32_i2c_traceevent(FAR struct stm32_i2c_priv_s *priv, + enum stm32_trace_e event, uint32_t parm) +{ + struct stm32_trace_s *trace; + + if (event != I2CEVENT_NONE) + { + trace = &priv->trace[priv->tndx]; + + /* Initialize the new trace entry */ + + trace->event = event; + trace->parm = parm; + + /* Bump up the trace index (unless we are out of trace entries) */ + + if (priv->tndx >= (CONFIG_I2C_NTRACE-1)) + { + i2cdbg("Trace table overflow\n"); + return; + } + + priv->tndx++; + stm32_i2c_traceclear(priv); + } +} + +static void stm32_i2c_tracedump(FAR struct stm32_i2c_priv_s *priv) +{ + struct stm32_trace_s *trace; + int i; + + lib_rawprintf("Elapsed time: %d\n", clock_systimer() - priv->start_time); + for (i = 0; i <= priv->tndx; i++) + { + trace = &priv->trace[i]; + lib_rawprintf("%2d. STATUS: %08x COUNT: %3d EVENT: %2d PARM: %08x TIME: %d\n", + i+1, trace->status, trace->count, trace->event, trace->parm, + trace->time - priv->start_time); + } +} +#endif /* CONFIG_I2C_TRACE */ + +/************************************************************************************ + * Name: stm32_i2c_setclock + * + * Description: + * Set the I2C clock + * + ************************************************************************************/ + +static void stm32_i2c_setclock(FAR struct stm32_i2c_priv_s *priv, uint32_t frequency) +{ + uint16_t cr1; + uint16_t ccr; + uint16_t trise; + uint16_t freqmhz; + uint16_t speed; + + /* Disable the selected I2C peripheral to configure TRISE */ + + cr1 = stm32_i2c_getreg(priv, STM32_I2C_CR1_OFFSET); + stm32_i2c_putreg(priv, STM32_I2C_CR1_OFFSET, cr1 & ~I2C_CR1_PE); + + /* Update timing and control registers */ + + freqmhz = (uint16_t)(STM32_PCLK1_FREQUENCY / 1000000); + ccr = 0; + + /* Configure speed in standard mode */ + + if (frequency <= 100000) + { + /* Standard mode speed calculation */ + + speed = (uint16_t)(STM32_PCLK1_FREQUENCY / (frequency << 1)); + + /* The CCR fault must be >= 4 */ + + if (speed < 4) + { + /* Set the minimum allowed value */ + + speed = 4; + } + ccr |= speed; + + /* Set Maximum Rise Time for standard mode */ + + trise = freqmhz + 1; + } + + /* Configure speed in fast mode */ + + else /* (frequency <= 400000) */ + { + /* Fast mode speed calculation with Tlow/Thigh = 16/9 */ + +#ifdef CONFIG_I2C_DUTY16_9 + speed = (uint16_t)(STM32_PCLK1_FREQUENCY / (frequency * 25)); + + /* Set DUTY and fast speed bits */ + + ccr |= (I2C_CCR_DUTY|I2C_CCR_FS); +#else + /* Fast mode speed calculation with Tlow/Thigh = 2 */ + + speed = (uint16_t)(STM32_PCLK1_FREQUENCY / (frequency * 3)); + + /* Set fast speed bit */ + + ccr |= I2C_CCR_FS; +#endif + + /* Verify that the CCR speed value is nonzero */ + + if (speed < 1) + { + /* Set the minimum allowed value */ + + speed = 1; + } + ccr |= speed; + + /* Set Maximum Rise Time for fast mode */ + + trise = (uint16_t)(((freqmhz * 300) / 1000) + 1); + } + + /* Write the new values of the CCR and TRISE registers */ + + stm32_i2c_putreg(priv, STM32_I2C_CCR_OFFSET, ccr); + stm32_i2c_putreg(priv, STM32_I2C_TRISE_OFFSET, trise); + + /* Bit 14 of OAR1 must be configured and kept at 1 */ + + stm32_i2c_putreg(priv, STM32_I2C_OAR1_OFFSET, I2C_OAR1_ONE); + + /* Re-enable the peripheral (or not) */ + + stm32_i2c_putreg(priv, STM32_I2C_CR1_OFFSET, cr1); +} + +/************************************************************************************ + * Name: stm32_i2c_sendstart + * + * Description: + * Send the START conditions/force Master mode + * + ************************************************************************************/ + +static inline void stm32_i2c_sendstart(FAR struct stm32_i2c_priv_s *priv) +{ + /* Disable ACK on receive by default and generate START */ + + stm32_i2c_modifyreg(priv, STM32_I2C_CR1_OFFSET, I2C_CR1_ACK, I2C_CR1_START); +} + +/************************************************************************************ + * Name: stm32_i2c_clrstart + * + * Description: + * Clear the STOP, START or PEC condition on certain error recovery steps. + * + ************************************************************************************/ + +static inline void stm32_i2c_clrstart(FAR struct stm32_i2c_priv_s *priv) +{ + /* "Note: When the STOP, START or PEC bit is set, the software must + * not perform any write access to I2C_CR1 before this bit is + * cleared by hardware. Otherwise there is a risk of setting a + * second STOP, START or PEC request." + * + * "The [STOP] bit is set and cleared by software, cleared by hardware + * when a Stop condition is detected, set by hardware when a timeout + * error is detected. + * + * "This [START] bit is set and cleared by software and cleared by hardware + * when start is sent or PE=0." The bit must be cleared by software if the + * START is never sent. + * + * "This [PEC] bit is set and cleared by software, and cleared by hardware + * when PEC is transferred or by a START or Stop condition or when PE=0." + */ + + stm32_i2c_modifyreg(priv, STM32_I2C_CR1_OFFSET, + I2C_CR1_START|I2C_CR1_STOP|I2C_CR1_PEC, 0); +} + +/************************************************************************************ + * Name: stm32_i2c_sendstop + * + * Description: + * Send the STOP conditions + * + ************************************************************************************/ + +static inline void stm32_i2c_sendstop(FAR struct stm32_i2c_priv_s *priv) +{ + stm32_i2c_modifyreg(priv, STM32_I2C_CR1_OFFSET, I2C_CR1_ACK, I2C_CR1_STOP); +} + +/************************************************************************************ + * Name: stm32_i2c_getstatus + * + * Description: + * Get 32-bit status (SR1 and SR2 combined) + * + ************************************************************************************/ + +static inline uint32_t stm32_i2c_getstatus(FAR struct stm32_i2c_priv_s *priv) +{ + uint32_t status = stm32_i2c_getreg(priv, STM32_I2C_SR1_OFFSET); + status |= (stm32_i2c_getreg(priv, STM32_I2C_SR2_OFFSET) << 16); + return status; +} + +/************************************************************************************ + * Name: stm32_i2c_disablefsmc + * + * Description: + * FSMC must be disable while accessing I2C1 because it uses a common resource + * (LBAR) + * + * NOTE: This is an issue with the STM32F103ZE, but may not be an issue with other + * STM32s. You may need to experiment + * + ************************************************************************************/ + +#ifdef I2C1_FSMC_CONFLICT +static inline uint32_t stm32_i2c_disablefsmc(FAR struct stm32_i2c_priv_s *priv) +{ + uint32_t ret = 0; + uint32_t regval; + + /* Is this I2C1 */ + +#ifdef CONFIG_STM32_I2C2 + if (priv->base == STM32_I2C1_BASE) +#endif + { + /* Disable FSMC unconditionally */ + + ret = getreg32( STM32_RCC_AHBENR); + regval = ret & ~RCC_AHBENR_FSMCEN; + putreg32(regval, STM32_RCC_AHBENR); + } + return ret; +} + +/************************************************************************************ + * Name: stm32_i2c_enablefsmc + * + * Description: + * Re-enabled the FSMC + * + ************************************************************************************/ + +static inline void stm32_i2c_enablefsmc(uint32_t ahbenr) +{ + uint32_t regval; + + /* Enable AHB clocking to the FSMC only if it was previously enabled. */ + + if ((ahbenr & RCC_AHBENR_FSMCEN) != 0) + { + regval = getreg32( STM32_RCC_AHBENR); + regval |= RCC_AHBENR_FSMCEN; + putreg32(regval, STM32_RCC_AHBENR); + } +} +#else +# define stm32_i2c_disablefsmc(priv) (0) +# define stm32_i2c_enablefsmc(ahbenr) +#endif /* I2C1_FSMC_CONFLICT */ + +/************************************************************************************ + * Name: stm32_i2c_isr + * + * Description: + * Common Interrupt Service Routine + * + ************************************************************************************/ + +static int stm32_i2c_isr(struct stm32_i2c_priv_s *priv) +{ + uint32_t status = stm32_i2c_getstatus(priv); + + /* Check for new trace setup */ + + stm32_i2c_tracenew(priv, status); + + /* Was start bit sent */ + + if ((status & I2C_SR1_SB) != 0) + { + stm32_i2c_traceevent(priv, I2CEVENT_SENDADDR, priv->msgc); + + /* Get run-time data */ + + priv->ptr = priv->msgv->buffer; + priv->dcnt = priv->msgv->length; + priv->flags = priv->msgv->flags; + + /* Send address byte and define addressing mode */ + + stm32_i2c_putreg(priv, STM32_I2C_DR_OFFSET, + (priv->flags & I2C_M_TEN) ? + 0 : ((priv->msgv->addr << 1) | (priv->flags & I2C_M_READ))); + + /* Set ACK for receive mode */ + + if (priv->dcnt > 1 && (priv->flags & I2C_M_READ) != 0) + { + stm32_i2c_modifyreg(priv, STM32_I2C_CR1_OFFSET, 0, I2C_CR1_ACK); + } + + /* Increment to next pointer and decrement message count */ + + priv->msgv++; + priv->msgc--; + } + + /* In 10-bit addressing mode, was first byte sent */ + + else if ((status & I2C_SR1_ADD10) != 0) + { + /* TODO: Finish 10-bit mode addressing */ + } + + /* Was address sent, continue with either sending or reading data */ + + else if ((priv->flags & I2C_M_READ) == 0 && (status & (I2C_SR1_ADDR | I2C_SR1_TXE)) != 0) + { + if (priv->dcnt > 0) + { + /* Send a byte */ + + stm32_i2c_traceevent(priv, I2CEVENT_SENDBYTE, priv->dcnt); + stm32_i2c_putreg(priv, STM32_I2C_DR_OFFSET, *priv->ptr++); + priv->dcnt--; + } + } + + else if ((priv->flags & I2C_M_READ) != 0 && (status & I2C_SR1_ADDR) != 0) + { + /* Enable RxNE and TxE buffers in order to receive one or multiple bytes */ + +#ifndef CONFIG_I2C_POLLED + stm32_i2c_traceevent(priv, I2CEVENT_ITBUFEN, 0); + stm32_i2c_modifyreg(priv, STM32_I2C_CR2_OFFSET, 0, I2C_CR2_ITBUFEN); +#endif + } + + /* More bytes to read */ + + else if ((status & I2C_SR1_RXNE) != 0) + { + /* Read a byte, if dcnt goes < 0, then read dummy bytes to ack ISRs */ + + if (priv->dcnt > 0) + { + stm32_i2c_traceevent(priv, I2CEVENT_RCVBYTE, priv->dcnt); + + /* Receive a byte */ + + *priv->ptr++ = stm32_i2c_getreg(priv, STM32_I2C_DR_OFFSET); + + /* Disable acknowledge when last byte is to be received */ + + if (priv->dcnt == 1) + { + stm32_i2c_modifyreg(priv, STM32_I2C_CR1_OFFSET, I2C_CR1_ACK, 0); + } + priv->dcnt--; + } + } + + /* Do we have more bytes to send, enable/disable buffer interrupts + * (these ISRs could be replaced by DMAs) + */ + +#ifndef CONFIG_I2C_POLLED + if (priv->dcnt > 0) + { + stm32_i2c_traceevent(priv, I2CEVENT_REITBUFEN, 0); + stm32_i2c_modifyreg(priv, STM32_I2C_CR2_OFFSET, 0, I2C_CR2_ITBUFEN); + } + else if (priv->dcnt == 0) + { + stm32_i2c_traceevent(priv, I2CEVENT_DISITBUFEN, 0); + stm32_i2c_modifyreg(priv, STM32_I2C_CR2_OFFSET, I2C_CR2_ITBUFEN, 0); + } +#endif + + /* Was last byte received or sent? Hmmm... the F2 and F4 seems to differ from + * the F1 in that BTF is not set after data is received (only RXNE). + */ + +#if defined(CONFIG_STM32_STM32F20XX) || defined(CONFIG_STM32_STM32F40XX) + if (priv->dcnt <= 0 && (status & (I2C_SR1_BTF|I2C_SR1_RXNE)) != 0) +#else + if (priv->dcnt <= 0 && (status & I2C_SR1_BTF) != 0) +#endif + { + stm32_i2c_getreg(priv, STM32_I2C_DR_OFFSET); /* ACK ISR */ + + /* Do we need to terminate or restart after this byte? + * If there are more messages to send, then we may: + * + * - continue with repeated start + * - or just continue sending writeable part + * - or we close down by sending the stop bit + */ + + if (priv->msgc > 0) + { + if (priv->msgv->flags & I2C_M_NORESTART) + { + stm32_i2c_traceevent(priv, I2CEVENT_BTFNOSTART, priv->msgc); + priv->ptr = priv->msgv->buffer; + priv->dcnt = priv->msgv->length; + priv->flags = priv->msgv->flags; + priv->msgv++; + priv->msgc--; + + /* Restart this ISR! */ + +#ifndef CONFIG_I2C_POLLED + stm32_i2c_modifyreg(priv, STM32_I2C_CR2_OFFSET, 0, I2C_CR2_ITBUFEN); +#endif + } + else + { + stm32_i2c_traceevent(priv, I2CEVENT_BTFRESTART, priv->msgc); + stm32_i2c_sendstart(priv); + } + } + else if (priv->msgv) + { + stm32_i2c_traceevent(priv, I2CEVENT_BTFSTOP, 0); + stm32_i2c_sendstop(priv); + + /* Is there a thread waiting for this event (there should be) */ + +#ifndef CONFIG_I2C_POLLED + if (priv->intstate == INTSTATE_WAITING) + { + /* Yes.. inform the thread that the transfer is complete + * and wake it up. + */ + + sem_post( &priv->sem_isr ); + priv->intstate = INTSTATE_DONE; + } +#else + priv->intstate = INTSTATE_DONE; +#endif + + /* Mark that we have stopped with this transaction */ + + priv->msgv = NULL; + } + } + + /* Check for errors, in which case, stop the transfer and return + * Note that in master reception mode AF becomes set on last byte + * since ACK is not returned. We should ignore this error. + */ + + if ((status & I2C_SR1_ERRORMASK) != 0) + { + stm32_i2c_traceevent(priv, I2CEVENT_ERROR, 0); + + /* Clear interrupt flags */ + + stm32_i2c_putreg(priv, STM32_I2C_SR1_OFFSET, 0); + + /* Is there a thread waiting for this event (there should be) */ + +#ifndef CONFIG_I2C_POLLED + if (priv->intstate == INTSTATE_WAITING) + { + /* Yes.. inform the thread that the transfer is complete + * and wake it up. + */ + + sem_post( &priv->sem_isr ); + priv->intstate = INTSTATE_DONE; + } +#else + priv->intstate = INTSTATE_DONE; +#endif + } + + priv->status = status; + return OK; +} + +/************************************************************************************ + * Name: stm32_i2c1_isr + * + * Description: + * I2C1 interrupt service routine + * + ************************************************************************************/ + +#ifndef CONFIG_I2C_POLLED +#ifdef CONFIG_STM32_I2C1 +static int stm32_i2c1_isr(int irq, void *context) +{ + return stm32_i2c_isr(&stm32_i2c1_priv); +} +#endif + +/************************************************************************************ + * Name: stm32_i2c2_isr + * + * Description: + * I2C2 interrupt service routine + * + ************************************************************************************/ + +#ifdef CONFIG_STM32_I2C2 +static int stm32_i2c2_isr(int irq, void *context) +{ + return stm32_i2c_isr(&stm32_i2c2_priv); +} +#endif + +/************************************************************************************ + * Name: stm32_i2c3_isr + * + * Description: + * I2C2 interrupt service routine + * + ************************************************************************************/ + +#ifdef CONFIG_STM32_I2C3 +static int stm32_i2c3_isr(int irq, void *context) +{ + return stm32_i2c_isr(&stm32_i2c3_priv); +} +#endif +#endif + +/************************************************************************************ + * Private Initialization and Deinitialization + ************************************************************************************/ + +/************************************************************************************ + * Name: stm32_i2c_init + * + * Description: + * Setup the I2C hardware, ready for operation with defaults + * + ************************************************************************************/ + +static int stm32_i2c_init(FAR struct stm32_i2c_priv_s *priv) +{ + /* Power-up and configure GPIOs */ + + switch (priv->base) + { +#ifdef CONFIG_STM32_I2C1 + case STM32_I2C1_BASE: + + /* Enable power and reset the peripheral */ + + modifyreg32(STM32_RCC_APB1ENR, 0, RCC_APB1ENR_I2C1EN); + + modifyreg32(STM32_RCC_APB1RSTR, 0, RCC_APB1RSTR_I2C1RST); + modifyreg32(STM32_RCC_APB1RSTR, RCC_APB1RSTR_I2C1RST, 0); + + /* Configure pins */ + + if (stm32_configgpio(GPIO_I2C1_SCL) < 0) + { + return ERROR; + } + + if (stm32_configgpio(GPIO_I2C1_SDA) < 0) + { + stm32_unconfiggpio(GPIO_I2C1_SCL); + return ERROR; + } + + /* Attach ISRs */ + +#ifndef CONFIG_I2C_POLLED + irq_attach(STM32_IRQ_I2C1EV, stm32_i2c1_isr); + irq_attach(STM32_IRQ_I2C1ER, stm32_i2c1_isr); + up_enable_irq(STM32_IRQ_I2C1EV); + up_enable_irq(STM32_IRQ_I2C1ER); +#endif + break; +#endif + +#ifdef CONFIG_STM32_I2C2 + case STM32_I2C2_BASE: + + /* Enable power and reset the peripheral */ + + modifyreg32(STM32_RCC_APB1ENR, 0, RCC_APB1ENR_I2C2EN); + + modifyreg32(STM32_RCC_APB1RSTR, 0, RCC_APB1RSTR_I2C2RST); + modifyreg32(STM32_RCC_APB1RSTR, RCC_APB1RSTR_I2C2RST, 0); + + /* Configure pins */ + + if (stm32_configgpio(GPIO_I2C2_SCL) < 0) + { + return ERROR; + } + + if (stm32_configgpio(GPIO_I2C2_SDA) < 0) + { + stm32_unconfiggpio(GPIO_I2C2_SCL); + return ERROR; + } + + /* Attach ISRs */ + +#ifndef CONFIG_I2C_POLLED + irq_attach(STM32_IRQ_I2C2EV, stm32_i2c2_isr); + irq_attach(STM32_IRQ_I2C2ER, stm32_i2c2_isr); + up_enable_irq(STM32_IRQ_I2C2EV); + up_enable_irq(STM32_IRQ_I2C2ER); +#endif + break; +#endif + +#ifdef CONFIG_STM32_I2C3 + case STM32_I2C3_BASE: + + /* Enable power and reset the peripheral */ + + modifyreg32(STM32_RCC_APB1ENR, 0, RCC_APB1ENR_I2C3EN); + + modifyreg32(STM32_RCC_APB1RSTR, 0, RCC_APB1RSTR_I2C3RST); + modifyreg32(STM32_RCC_APB1RSTR, RCC_APB1RSTR_I2C3RST, 0); + + /* Configure pins */ + + if (stm32_configgpio(GPIO_I2C3_SCL) < 0) + { + return ERROR; + } + + if (stm32_configgpio(GPIO_I2C3_SDA) < 0) + { + stm32_unconfiggpio(GPIO_I2C3_SCL); + return ERROR; + } + + /* Attach ISRs */ + +#ifndef CONFIG_I2C_POLLED + irq_attach(STM32_IRQ_I2C3EV, stm32_i2c3_isr); + irq_attach(STM32_IRQ_I2C3ER, stm32_i2c3_isr); + up_enable_irq(STM32_IRQ_I2C3EV); + up_enable_irq(STM32_IRQ_I2C3ER); +#endif + break; +#endif + + default: + return ERROR; + } + + /* Set peripheral frequency, where it must be at least 2 MHz for 100 kHz + * or 4 MHz for 400 kHz. This also disables all I2C interrupts. + */ + + stm32_i2c_putreg(priv, STM32_I2C_CR2_OFFSET, (STM32_PCLK1_FREQUENCY / 1000000)); + stm32_i2c_setclock(priv, 100000); + + /* Enable I2C */ + + stm32_i2c_putreg(priv, STM32_I2C_CR1_OFFSET, I2C_CR1_PE); + return OK; +} + +/************************************************************************************ + * Name: stm32_i2c_deinit + * + * Description: + * Shutdown the I2C hardware + * + ************************************************************************************/ + +static int stm32_i2c_deinit(FAR struct stm32_i2c_priv_s *priv) +{ + /* Disable I2C */ + + stm32_i2c_putreg(priv, STM32_I2C_CR1_OFFSET, 0); + + switch (priv->base) + { +#ifdef CONFIG_STM32_I2C1 + case STM32_I2C1_BASE: + stm32_unconfiggpio(GPIO_I2C1_SCL); + stm32_unconfiggpio(GPIO_I2C1_SDA); + +#ifndef CONFIG_I2C_POLLED + up_disable_irq(STM32_IRQ_I2C1EV); + up_disable_irq(STM32_IRQ_I2C1ER); + irq_detach(STM32_IRQ_I2C1EV); + irq_detach(STM32_IRQ_I2C1ER); +#endif + modifyreg32(STM32_RCC_APB1ENR, RCC_APB1ENR_I2C1EN, 0); + break; +#endif + +#ifdef CONFIG_STM32_I2C2 + case STM32_I2C2_BASE: + stm32_unconfiggpio(GPIO_I2C2_SCL); + stm32_unconfiggpio(GPIO_I2C2_SDA); + +#ifndef CONFIG_I2C_POLLED + up_disable_irq(STM32_IRQ_I2C2EV); + up_disable_irq(STM32_IRQ_I2C2ER); + irq_detach(STM32_IRQ_I2C2EV); + irq_detach(STM32_IRQ_I2C2ER); +#endif + modifyreg32(STM32_RCC_APB1ENR, RCC_APB1ENR_I2C2EN, 0); + break; +#endif + + default: + return ERROR; + } + + return OK; +} + +/************************************************************************************ + * Device Driver Operations + ************************************************************************************/ + +/************************************************************************************ + * Name: stm32_i2c_setfrequency + * + * Description: + * Set the I2C frequency + * + ************************************************************************************/ + +static uint32_t stm32_i2c_setfrequency(FAR struct i2c_dev_s *dev, uint32_t frequency) +{ + stm32_i2c_sem_wait(dev); + +#if STM32_PCLK1_FREQUENCY < 4000000 + ((struct stm32_i2c_inst_s *)dev)->frequency = 100000; +#else + ((struct stm32_i2c_inst_s *)dev)->frequency = frequency; +#endif + + stm32_i2c_sem_post(dev); + return ((struct stm32_i2c_inst_s *)dev)->frequency; +} + +/************************************************************************************ + * Name: stm32_i2c_setaddress + * + * Description: + * Set the I2C slave address + * + ************************************************************************************/ + +static int stm32_i2c_setaddress(FAR struct i2c_dev_s *dev, int addr, int nbits) +{ + stm32_i2c_sem_wait(dev); + + ((struct stm32_i2c_inst_s *)dev)->address = addr; + ((struct stm32_i2c_inst_s *)dev)->flags = (nbits == 10) ? I2C_M_TEN : 0; + + stm32_i2c_sem_post(dev); + return OK; +} + +/************************************************************************************ + * Name: stm32_i2c_process + * + * Description: + * Common I2C transfer logic + * + ************************************************************************************/ + +static int stm32_i2c_process(FAR struct i2c_dev_s *dev, FAR struct i2c_msg_s *msgs, int count) +{ + struct stm32_i2c_inst_s *inst = (struct stm32_i2c_inst_s *)dev; + FAR struct stm32_i2c_priv_s *priv = inst->priv; + uint32_t status = 0; + uint32_t ahbenr; + int errval = 0; + + ASSERT(count); + + /* Disable FSMC that shares a pin with I2C1 (LBAR) */ + + ahbenr = stm32_i2c_disablefsmc(priv); + + /* Wait for any STOP in progress. NOTE: If we have to disable the FSMC + * then we cannot do this at the top of the loop, unfortunately. The STOP + * will not complete normally if the FSMC is enabled. + */ + +#ifndef I2C1_FSMC_CONFLICT + stm32_i2c_sem_waitstop(priv); +#endif + + /* Clear any pending error interrupts */ + + stm32_i2c_putreg(priv, STM32_I2C_SR1_OFFSET, 0); + + /* "Note: When the STOP, START or PEC bit is set, the software must + * not perform any write access to I2C_CR1 before this bit is + * cleared by hardware. Otherwise there is a risk of setting a + * second STOP, START or PEC request." However, if the bits are + * not cleared by hardware, then we will have to do that from hardware. + */ + + stm32_i2c_clrstart(priv); + + /* Old transfers are done */ + + priv->msgv = msgs; + priv->msgc = count; + + /* Reset I2C trace logic */ + + stm32_i2c_tracereset(priv); + + /* Set I2C clock frequency (on change it toggles I2C_CR1_PE !) */ + + stm32_i2c_setclock(priv, inst->frequency); + + /* Trigger start condition, then the process moves into the ISR. I2C + * interrupts will be enabled within stm32_i2c_waitdone(). + */ + + priv->status = 0; + stm32_i2c_sendstart(priv); + + /* Wait for an ISR, if there was a timeout, fetch latest status to get + * the BUSY flag. + */ + + if (stm32_i2c_sem_waitdone(priv) < 0) + { + status = stm32_i2c_getstatus(priv); + errval = ETIMEDOUT; + + i2cdbg("Timed out: CR1: %04x status: %08x\n", + stm32_i2c_getreg(priv, STM32_I2C_CR1_OFFSET), status); + + /* "Note: When the STOP, START or PEC bit is set, the software must + * not perform any write access to I2C_CR1 before this bit is + * cleared by hardware. Otherwise there is a risk of setting a + * second STOP, START or PEC request." + */ + + stm32_i2c_clrstart(priv); + } + else + { + /* clear SR2 (BUSY flag) as we've done successfully */ + + status = priv->status & 0xffff; + } + + /* Check for error status conditions */ + + if ((status & I2C_SR1_ERRORMASK) != 0) + { + /* I2C_SR1_ERRORMASK is the 'OR' of the following individual bits: */ + + if (status & I2C_SR1_BERR) + { + /* Bus Error */ + + errval = EIO; + } + else if (status & I2C_SR1_ARLO) + { + /* Arbitration Lost (master mode) */ + + errval = EAGAIN; + } + else if (status & I2C_SR1_AF) + { + /* Acknowledge Failure */ + + errval = ENXIO; + } + else if (status & I2C_SR1_OVR) + { + /* Overrun/Underrun */ + + errval = EIO; + } + else if (status & I2C_SR1_PECERR) + { + /* PEC Error in reception */ + + errval = EPROTO; + } + else if (status & I2C_SR1_TIMEOUT) + { + /* Timeout or Tlow Error */ + + errval = ETIME; + } + + /* This is not an error and should never happen since SMBus is not enabled */ + + else /* if (status & I2C_SR1_SMBALERT) */ + { + /* SMBus alert is an optional signal with an interrupt line for devices + * that want to trade their ability to master for a pin. + */ + + errval = EINTR; + } + } + + /* This is not an error, but should not happen. The BUSY signal can hang, + * however, if there are unhealthy devices on the bus that need to be reset. + * NOTE: We will only see this buy indication if stm32_i2c_sem_waitdone() + * fails above; Otherwise it is cleared. + */ + + else if ((status & (I2C_SR2_BUSY << 16)) != 0) + { + /* I2C Bus is for some reason busy */ + + errval = EBUSY; + } + + /* Dump the trace result */ + + stm32_i2c_tracedump(priv); + + /* Wait for any STOP in progress. NOTE: If we have to disable the FSMC + * then we cannot do this at the top of the loop, unfortunately. The STOP + * will not complete normally if the FSMC is enabled. + */ + +#ifdef I2C1_FSMC_CONFLICT + stm32_i2c_sem_waitstop(priv); +#endif + + /* Re-enable the FSMC */ + + stm32_i2c_enablefsmc(ahbenr); + stm32_i2c_sem_post(dev); + + return -errval; +} + +/************************************************************************************ + * Name: stm32_i2c_write + * + * Description: + * Write I2C data + * + ************************************************************************************/ + +static int stm32_i2c_write(FAR struct i2c_dev_s *dev, const uint8_t *buffer, int buflen) +{ + stm32_i2c_sem_wait(dev); /* ensure that address or flags don't change meanwhile */ + + struct i2c_msg_s msgv = + { + .addr = ((struct stm32_i2c_inst_s *)dev)->address, + .flags = ((struct stm32_i2c_inst_s *)dev)->flags, + .buffer = (uint8_t *)buffer, + .length = buflen + }; + + return stm32_i2c_process(dev, &msgv, 1); +} + +/************************************************************************************ + * Name: stm32_i2c_read + * + * Description: + * Read I2C data + * + ************************************************************************************/ + +int stm32_i2c_read(FAR struct i2c_dev_s *dev, uint8_t *buffer, int buflen) +{ + stm32_i2c_sem_wait(dev); /* ensure that address or flags don't change meanwhile */ + + struct i2c_msg_s msgv = + { + .addr = ((struct stm32_i2c_inst_s *)dev)->address, + .flags = ((struct stm32_i2c_inst_s *)dev)->flags | I2C_M_READ, + .buffer = buffer, + .length = buflen + }; + + return stm32_i2c_process(dev, &msgv, 1); +} + +/************************************************************************************ + * Name: stm32_i2c_writeread + * + * Description: + * Read then write I2C data + * + ************************************************************************************/ + +#ifdef CONFIG_I2C_WRITEREAD +static int stm32_i2c_writeread(FAR struct i2c_dev_s *dev, + const uint8_t *wbuffer, int wbuflen, + uint8_t *buffer, int buflen) +{ + stm32_i2c_sem_wait(dev); /* ensure that address or flags don't change meanwhile */ + + struct i2c_msg_s msgv[2] = + { + { + .addr = ((struct stm32_i2c_inst_s *)dev)->address, + .flags = ((struct stm32_i2c_inst_s *)dev)->flags, + .buffer = (uint8_t *)wbuffer, /* this is really ugly, sorry const ... */ + .length = wbuflen + }, + { + .addr = ((struct stm32_i2c_inst_s *)dev)->address, + .flags = ((struct stm32_i2c_inst_s *)dev)->flags | ((buflen>0) ? I2C_M_READ : I2C_M_NORESTART), + .buffer = buffer, + .length = (buflen>0) ? buflen : -buflen + } + }; + + return stm32_i2c_process(dev, msgv, 2); +} +#endif + +/************************************************************************************ + * Name: stm32_i2c_transfer + * + * Description: + * Generic I2C transfer function + * + ************************************************************************************/ + +#ifdef CONFIG_I2C_TRANSFER +static int stm32_i2c_transfer(FAR struct i2c_dev_s *dev, FAR struct i2c_msg_s *msgs, + int count) +{ + stm32_i2c_sem_wait(dev); /* ensure that address or flags don't change meanwhile */ + return stm32_i2c_process(dev, msgs, count); +} +#endif + +/************************************************************************************ + * Public Functions + ************************************************************************************/ + +/************************************************************************************ + * Name: up_i2cinitialize + * + * Description: + * Initialize one I2C bus + * + ************************************************************************************/ + +FAR struct i2c_dev_s *up_i2cinitialize(int port) +{ + struct stm32_i2c_priv_s * priv = NULL; /* private data of device with multiple instances */ + struct stm32_i2c_inst_s * inst = NULL; /* device, single instance */ + int irqs; + +#if STM32_PCLK1_FREQUENCY < 4000000 +# warning STM32_I2C_INIT: Peripheral clock must be at least 4 MHz to support 400 kHz operation. +#endif + +#if STM32_PCLK1_FREQUENCY < 2000000 +# warning STM32_I2C_INIT: Peripheral clock must be at least 2 MHz to support 100 kHz operation. + return NULL; +#endif + + /* Get I2C private structure */ + + switch (port) + { +#ifdef CONFIG_STM32_I2C1 + case 1: + priv = (struct stm32_i2c_priv_s *)&stm32_i2c1_priv; + break; +#endif +#ifdef CONFIG_STM32_I2C2 + case 2: + priv = (struct stm32_i2c_priv_s *)&stm32_i2c2_priv; + break; +#endif +#ifdef CONFIG_STM32_I2C3 + case 3: + priv = (struct stm32_i2c_priv_s *)&stm32_i2c3_priv; + break; +#endif + default: + return NULL; + } + + /* Allocate instance */ + + if (!(inst = kmalloc( sizeof(struct stm32_i2c_inst_s)))) + { + return NULL; + } + + /* Initialize instance */ + + inst->ops = &stm32_i2c_ops; + inst->priv = priv; + inst->frequency = 100000; + inst->address = 0; + inst->flags = 0; + + /* Init private data for the first time, increment refs count, + * power-up hardware and configure GPIOs. + */ + + irqs = irqsave(); + + if ((volatile int)priv->refs++ == 0) + { + stm32_i2c_sem_init( (struct i2c_dev_s *)inst ); + stm32_i2c_init( priv ); + } + + irqrestore(irqs); + return (struct i2c_dev_s *)inst; +} + +/************************************************************************************ + * Name: up_i2cuninitialize + * + * Description: + * Uninitialize an I2C bus + * + ************************************************************************************/ + +int up_i2cuninitialize(FAR struct i2c_dev_s * dev) +{ + int irqs; + + ASSERT(dev); + + /* Decrement refs and check for underflow */ + + if (((struct stm32_i2c_inst_s *)dev)->priv->refs == 0) + { + return ERROR; + } + + irqs = irqsave(); + + if (--((struct stm32_i2c_inst_s *)dev)->priv->refs) + { + irqrestore(irqs); + kfree(dev); + return OK; + } + + irqrestore(irqs); + + /* Disable power and other HW resource (GPIO's) */ + + stm32_i2c_deinit( ((struct stm32_i2c_inst_s *)dev)->priv ); + + /* Release unused resources */ + + stm32_i2c_sem_destroy( (struct i2c_dev_s *)dev ); + + kfree(dev); + return OK; +} + +#endif /* defined(CONFIG_STM32_I2C1) && defined(CONFIG_STM32_I2C2) */ |