/* * File : ls1c_i2c.c * This file is part of RT-Thread RTOS * COPYRIGHT (C) 2006 - 2012, RT-Thread Development Team * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * * Change Logs: * Date Author Notes * 2017-09-06 ÇÚΪ±¾ first version */ // ·â×°Ó²¼þi2c½Ó¿Ú #include "ls1c_public.h" #include "ls1c_regs.h" #include "ls1c_clock.h" #include "ls1c_i2c.h" #include "ls1c_delay.h" /* * I2C¸÷¸ö¼Ä´æÆ÷Ïà¶Ô»ùµØÖ·µÄÆ«ÒÆ * ·¢ËÍÊý¾Ý¼Ä´æÆ÷ºÍ½ÓÊÕÊý¾Ý¼Ä´æÆ÷µÄÆ«ÒÆÊÇÏàͬµÄ * ÃüÁî¼Ä´æÆ÷ºÍ״̬¼Ä´æÆ÷µÄÆ«ÒÆÊÇÏàͬµÄ£¬²»Í¬µÄÊÇÃüÁî¼Ä´æÆ÷ֻд£¬×´Ì¬¼Ä´æÆ÷Ö»¶Á */ #define LS1C_I2C_PRER_LOW_OFFSET (0) // ·ÖÆµËø´æÆ÷µÍ×ֽڼĴæÆ÷Æ«ÒÆ #define LS1C_I2C_PRER_HIGH_OFFSET (1) // ·ÖÆµËø´æÆ÷¸ß×ֽڼĴæÆ÷Æ«ÒÆ #define LS1C_I2C_CONTROL_OFFSET (2) // ¿ØÖƼĴæÆ÷Æ«ÒÆ #define LS1C_I2C_DATA_OFFSET (3) // ·¢ËÍÊý¾Ý¼Ä´æÆ÷ºÍ½ÓÊÕÊý¾Ý¼Ä´æÆ÷µÄÆ«ÒÆÊÇÏàͬµÄ #define LS1C_I2C_CMD_OFFSET (4) // ÃüÁî¼Ä´æÆ÷Æ«ÒÆ£¬Ö»Ð´ #define LS1C_I2C_STATUS_OFFSET (4) // ״̬¼Ä´æÆ÷Æ«ÒÆ£¬Ö»¶Á // ¿ØÖƼĴæÆ÷µÄλÓò #define LS1C_I2C_CONTROL_EN (0x80) // i2cÄ£¿éʹÄÜ #define LS1C_I2C_CONTROL_IEN (0x40) // ÖжÏʹÄÜ // ÃüÁî¼Ä´æÆ÷µÄλÓò #define LS1C_I2C_CMD_START (0x90) // ²úÉúSTARTÐźŠ#define LS1C_I2C_CMD_STOP (0x40) // ²úÉúSTOPÐźŠ#define LS1C_I2C_CMD_READ (0x20) // ²úÉú¶ÁÐźţ¬¼´²úÉúACKÐźŠ#define LS1C_I2C_CMD_WRITE (0x10) // ²úÉúдÐźŠ#define LS1C_I2C_CMD_READ_ACK (0x20) // ²úÉúACKÐźţ¬Óë¶ÁÐźÅÏàͬ #define LS1C_I2C_CMD_READ_NACK (0x28) // ²úÉúNACKÐźŠ#define LS1C_I2C_CMD_IACK (0x00) // ²úÉúÖжÏÓ¦´ðÐźŠ// ״̬¼Ä´æÆ÷µÄλÓò #define LS1C_I2C_STATUS_IF (0x01) // Öжϱê־λ #define LS1C_I2C_STATUS_TIP (0x02) // ָʾ´«ÊäµÄ¹ý³Ì¡£1£¬ÕýÔÚ´«Ê䣻0£¬´«ÊäÍê³É #define LS1C_I2C_STATUS_ARBLOST (0x20) // I2CºËʧȥI2C×ÜÏߵĿØÖÆÈ¨ #define LS1C_I2C_STATUS_BUSY (0x40) // I2C×ÜÏßæ±êÖ¾ #define LS1C_I2C_STATUS_NACK (0x80) // Ó¦´ðλ±êÖ¾¡£1£¬Ã»ÊÕµ½Ó¦´ðλ£»0£¬ÊÕµ½Ó¦´ðλ /* * »ñȡָ¶¨i2cÄ£¿éµÄ»ùµØÖ· * @I2Cx I2CÄ£¿éµÄ±àºÅ */ void *i2c_get_base(ls1c_i2c_t I2Cx) { void *base = NULL; switch (I2Cx) { case LS1C_I2C_0: base = (void *)LS1C_I2C0_BASE; break; case LS1C_I2C_1: base = (void *)LS1C_I2C1_BASE; break; case LS1C_I2C_2: base = (void *)LS1C_I2C2_BASE; break; default: base = NULL; break; } return base; } /* * ÏòÃüÁî¼Ä´æÆ÷дÃüÁî * @i2c_info_p i2cÄ£¿éÐÅÏ¢ * @cmd ÃüÁî */ void i2c_cmd(ls1c_i2c_info_t *i2c_info_p, unsigned char cmd) { void *i2c_base = i2c_get_base(i2c_info_p->I2Cx); reg_write_8(cmd, i2c_base + LS1C_I2C_CMD_OFFSET); return ; } /* * Ö´ÐÐSTARTÃüÁ·¢ËÍSTARTÐźŠ* @i2c_info_p i2cÄ£¿éÐÅÏ¢ */ void i2c_cmd_start(ls1c_i2c_info_t *i2c_info_p) { i2c_cmd(i2c_info_p, LS1C_I2C_CMD_START); return ; } /* * Ö´ÐÐSTOPÃüÁ·¢ËÍSTOPÐźŠ* @i2c_info_p i2cÄ£¿éÐÅÏ¢ */ void i2c_cmd_stop(ls1c_i2c_info_t *i2c_info_p) { i2c_cmd(i2c_info_p, LS1C_I2C_CMD_STOP); return ; } /* * Ö´ÐÐдÃüÁî * @i2c_info_p i2cÄ£¿éÐÅÏ¢ */ void i2c_cmd_write(ls1c_i2c_info_t *i2c_info_p) { i2c_cmd(i2c_info_p, LS1C_I2C_CMD_WRITE); return ; } /* * Ö´ÐжÁackÃüÁ·¢ËͶÁackÐźŠ* @i2c_info_p i2cÄ£¿éÐÅÏ¢ */ void i2c_cmd_read_ack(ls1c_i2c_info_t *i2c_info_p) { i2c_cmd(i2c_info_p, LS1C_I2C_CMD_READ_ACK); return ; } /* * Ö´ÐжÁnackÃüÁî,·¢ËͶÁnackÐźŠ* @i2c_info_p i2cÄ£¿éÐÅÏ¢ */ void i2c_cmd_read_nack(ls1c_i2c_info_t *i2c_info_p) { i2c_cmd(i2c_info_p, LS1C_I2C_CMD_READ_NACK); return ; } /* * ·¢ËÍÖжÏÓ¦´ðÐźŠ* @i2c_info_p i2cÄ£¿éÐÅÏ¢ */ void i2c_cmd_iack(ls1c_i2c_info_t *i2c_info_p) { i2c_cmd(i2c_info_p, LS1C_I2C_CMD_IACK); return ; } /* * »ñȡ״̬¼Ä´æÆ÷µÄÖµ * @i2c_info_p i2cÄ£¿éÐÅÏ¢ * @ret ״̬¼Ä´æÆ÷µÄÖµ */ unsigned char i2c_get_status(ls1c_i2c_info_t *i2c_info_p) { void *i2c_base = i2c_get_base(i2c_info_p->I2Cx); return reg_read_8(i2c_base + LS1C_I2C_STATUS_OFFSET); } /* * Poll the i2c status register until the specified bit is set. * Returns 0 if timed out (100 msec). * @i2c_info_p i2cÄ£¿éÐÅÏ¢ * @bit ¼Ä´æÆ÷µÄijһλ * @ret true or false */ int i2c_poll_status(ls1c_i2c_info_t *i2c_info_p, unsigned long bit) { int loop_cntr = 20000; do { delay_us(1); } while ((i2c_get_status(i2c_info_p) & bit) && (0 < --loop_cntr)); return (0 < loop_cntr); } /* * ³õʼ»¯Ö¸¶¨i2cÄ£¿é * @i2c_info_p ij¸öi2cÄ£¿éµÄÐÅÏ¢ */ void i2c_init(ls1c_i2c_info_t *i2c_info_p) { void *i2c_base = i2c_get_base(i2c_info_p->I2Cx); unsigned long i2c_clock = i2c_info_p->clock; unsigned char ctrl = reg_read_8(i2c_base + LS1C_I2C_CONTROL_OFFSET); unsigned long prescale = 0; /* make sure the device is disabled */ ctrl = ctrl & ~(LS1C_I2C_CONTROL_EN | LS1C_I2C_CONTROL_IEN); reg_write_8(ctrl, i2c_base + LS1C_I2C_CONTROL_OFFSET); // ÉèÖÃʱÖÓ i2c_clock = MIN(i2c_clock, LS1C_I2C_CLOCK_MAX); // ÏÞÖÆÔÚ×î´óÔÊÐí·¶Î§ÄÚ prescale = clk_get_apb_rate(); prescale = (prescale / (5 * i2c_clock)) - 1; reg_write_8(prescale & 0xff, i2c_base + LS1C_I2C_PRER_LOW_OFFSET); reg_write_8(prescale >> 8, i2c_base + LS1C_I2C_PRER_HIGH_OFFSET); // ʹÄÜ i2c_cmd_iack(i2c_info_p); ctrl = ctrl | LS1C_I2C_CONTROL_EN; reg_write_8(ctrl, i2c_base + LS1C_I2C_CONTROL_OFFSET); return ; } /* * (ÔÙ·¢ËÍÒ»¸ö×Ö½ÚÊý¾ÝÖ®ºó)½ÓÊÕ´Ó»ú·¢Ë͵ÄACKÐźŠ* @i2c_info_p i2cÄ£¿éÐÅÏ¢ * @ret LS1C_I2C_ACK or LS1C_I2C_NACK */ ls1c_i2c_ack_t i2c_receive_ack(ls1c_i2c_info_t *i2c_info_p) { ls1c_i2c_ack_t ret = LS1C_I2C_NACK; if (LS1C_I2C_STATUS_NACK & i2c_get_status(i2c_info_p)) { ret = LS1C_I2C_NACK; } else { ret = LS1C_I2C_ACK; } return ret; } /* * ½ÓÊÕÊý¾Ý * @i2c_info_p i2cÄ£¿éÐÅÏ¢ * @buf Êý¾Ý»º´æ * @len ´ý½ÓÊÕÊý¾ÝµÄ³¤¶È */ ls1c_i2c_ret_t i2c_receive_data(ls1c_i2c_info_t *i2c_info_p, unsigned char *buf, int len) { void *i2c_base = i2c_get_base(i2c_info_p->I2Cx); int i = 0; for (i=0; i<len; i++) { // ¿ªÊ¼½ÓÊÕ if (i != (len - 1)) i2c_cmd_read_ack(i2c_info_p); else i2c_cmd_read_nack(i2c_info_p); // µÈ´ý£¬Ö±µ½½ÓÊÕÍê³É if (!i2c_poll_status(i2c_info_p, LS1C_I2C_STATUS_TIP)) return LS1C_I2C_RET_TIMEOUT; // ¶ÁÈ¡Êý¾Ý£¬²¢±£´æ *buf++ = reg_read_8(i2c_base + LS1C_I2C_DATA_OFFSET); } return LS1C_I2C_RET_OK; } /* * ·¢ËÍSTARTÐźź͵ØÖ· * @i2c_info_p i2cÄ£¿éÐÅÏ¢ * @slave_addr ´Ó»úµØÖ· * @direction Êý¾Ý´«Êä·½Ïò(¶Á¡¢Ð´) */ ls1c_i2c_ret_t i2c_send_start_and_addr(ls1c_i2c_info_t *i2c_info_p, unsigned char slave_addr, ls1c_i2c_direction_t direction) { void *i2c_base = i2c_get_base(i2c_info_p->I2Cx); unsigned char data = 0; // µÈ´ýi2c×ÜÏß¿ÕÏÐ if (!i2c_poll_status(i2c_info_p, LS1C_I2C_STATUS_BUSY)) return LS1C_I2C_RET_TIMEOUT; // Ìî³äµØÖ·µ½Êý¾Ý¼Ä´æÆ÷ data = (slave_addr << 1) | ((LS1C_I2C_DIRECTION_READ == direction) ? 1 : 0); reg_write_8(data , i2c_base + LS1C_I2C_DATA_OFFSET); // ¿ªÊ¼·¢ËÍ i2c_cmd_start(i2c_info_p); // µÈ´ý£¬Ö±µ½·¢ËÍÍê³É if (!i2c_poll_status(i2c_info_p, LS1C_I2C_STATUS_TIP)) return LS1C_I2C_RET_TIMEOUT; return LS1C_I2C_RET_OK; } /* * ·¢ËÍÊý¾Ý * @i2c_info_p i2cÄ£¿éÐÅÏ¢ * @data ´ý·¢Ë͵ÄÊý¾Ý * @len ´ý·¢ËÍÊý¾ÝµÄ³¤¶È */ ls1c_i2c_ret_t i2c_send_data(ls1c_i2c_info_t *i2c_info_p, unsigned char *data, int len) { void *i2c_base = i2c_get_base(i2c_info_p->I2Cx); int i = 0; for (i=0; i<len; i++) { // ½«Ò»¸ö×Ö½ÚÊý¾ÝдÈëÊý¾Ý¼Ä´æÆ÷ reg_write_8(*data++, i2c_base + LS1C_I2C_DATA_OFFSET); // ¿ªÊ¼·¢ËÍ reg_write_8(LS1C_I2C_CMD_WRITE, i2c_base + LS1C_I2C_CMD_OFFSET); // µÈ´ý£¬Ö±µ½·¢ËÍÍê³É if (!i2c_poll_status(i2c_info_p, LS1C_I2C_STATUS_TIP)) return LS1C_I2C_RET_TIMEOUT; // ¶ÁȡӦ´ðÐźŠif (LS1C_I2C_ACK != i2c_receive_ack(i2c_info_p)) return len; } return LS1C_I2C_RET_OK; } /* * ·¢ËÍSTOPÐźŠ* @i2c_info_p i2cÄ£¿éÐÅÏ¢ */ void i2c_send_stop(ls1c_i2c_info_t *i2c_info_p) { i2c_cmd_stop(i2c_info_p); return ; }