1 /* 2 * (C) Copyright 2011 3 * Holger Brunck, Keymile GmbH Hannover, holger.brunck@keymile.com 4 * 5 * See file CREDITS for list of people who contributed to this 6 * project. 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License as 10 * published by the Free Software Foundation; either version 2 of 11 * the License, or (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21 * MA 02111-1307 USA 22 */ 23 24 #include <common.h> 25 #include <i2c.h> 26 #include <asm/io.h> 27 #include <linux/ctype.h> 28 #include "../common/common.h" 29 30 static void i2c_write_start_seq(void) 31 { 32 struct fsl_i2c *dev; 33 dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET); 34 udelay(DELAY_ABORT_SEQ); 35 out_8(&dev->cr, (I2C_CR_MEN | I2C_CR_MSTA)); 36 udelay(DELAY_ABORT_SEQ); 37 out_8(&dev->cr, (I2C_CR_MEN)); 38 } 39 40 int i2c_make_abort(void) 41 { 42 struct fsl_i2c *dev; 43 dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET); 44 uchar dummy; 45 uchar last; 46 int nbr_read = 0; 47 int i = 0; 48 int ret = 0; 49 50 /* wait after each operation to finsh with a delay */ 51 out_8(&dev->cr, (I2C_CR_MSTA)); 52 udelay(DELAY_ABORT_SEQ); 53 out_8(&dev->cr, (I2C_CR_MEN | I2C_CR_MSTA)); 54 udelay(DELAY_ABORT_SEQ); 55 dummy = in_8(&dev->dr); 56 udelay(DELAY_ABORT_SEQ); 57 last = in_8(&dev->dr); 58 nbr_read++; 59 60 /* 61 * do read until the last bit is 1, but stop if the full eeprom is 62 * read. 63 */ 64 while (((last & 0x01) != 0x01) && 65 (nbr_read < CONFIG_SYS_IVM_EEPROM_MAX_LEN)) { 66 udelay(DELAY_ABORT_SEQ); 67 last = in_8(&dev->dr); 68 nbr_read++; 69 } 70 if ((last & 0x01) != 0x01) 71 ret = -2; 72 if ((last != 0xff) || (nbr_read > 1)) 73 printf("[INFO] i2c abort after %d bytes (0x%02x)\n", 74 nbr_read, last); 75 udelay(DELAY_ABORT_SEQ); 76 out_8(&dev->cr, (I2C_CR_MEN)); 77 udelay(DELAY_ABORT_SEQ); 78 /* clear status reg */ 79 out_8(&dev->sr, 0); 80 81 for (i = 0; i < 5; i++) 82 i2c_write_start_seq(); 83 if (ret != 0) 84 printf("[ERROR] i2c abort failed after %d bytes (0x%02x)\n", 85 nbr_read, last); 86 87 return ret; 88 } 89