1 /* 2 * (C) Copyright 2011 3 * Holger Brunck, Keymile GmbH Hannover, holger.brunck@keymile.com 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <i2c.h> 10 #include <asm/io.h> 11 #include <linux/ctype.h> 12 #include "../common/common.h" 13 14 static void i2c_write_start_seq(void) 15 { 16 struct fsl_i2c_base *base; 17 base = (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + 18 CONFIG_SYS_I2C_OFFSET); 19 udelay(DELAY_ABORT_SEQ); 20 out_8(&base->cr, (I2C_CR_MEN | I2C_CR_MSTA)); 21 udelay(DELAY_ABORT_SEQ); 22 out_8(&base->cr, (I2C_CR_MEN)); 23 } 24 25 int i2c_make_abort(void) 26 { 27 struct fsl_i2c_base *base; 28 base = (struct fsl_i2c_base *)(CONFIG_SYS_IMMR + 29 CONFIG_SYS_I2C_OFFSET); 30 uchar last; 31 int nbr_read = 0; 32 int i = 0; 33 int ret = 0; 34 35 /* wait after each operation to finsh with a delay */ 36 out_8(&base->cr, (I2C_CR_MSTA)); 37 udelay(DELAY_ABORT_SEQ); 38 out_8(&base->cr, (I2C_CR_MEN | I2C_CR_MSTA)); 39 udelay(DELAY_ABORT_SEQ); 40 in_8(&base->dr); 41 udelay(DELAY_ABORT_SEQ); 42 last = in_8(&base->dr); 43 nbr_read++; 44 45 /* 46 * do read until the last bit is 1, but stop if the full eeprom is 47 * read. 48 */ 49 while (((last & 0x01) != 0x01) && 50 (nbr_read < CONFIG_SYS_IVM_EEPROM_MAX_LEN)) { 51 udelay(DELAY_ABORT_SEQ); 52 last = in_8(&base->dr); 53 nbr_read++; 54 } 55 if ((last & 0x01) != 0x01) 56 ret = -2; 57 if ((last != 0xff) || (nbr_read > 1)) 58 printf("[INFO] i2c abort after %d bytes (0x%02x)\n", 59 nbr_read, last); 60 udelay(DELAY_ABORT_SEQ); 61 out_8(&base->cr, (I2C_CR_MEN)); 62 udelay(DELAY_ABORT_SEQ); 63 /* clear status reg */ 64 out_8(&base->sr, 0); 65 66 for (i = 0; i < 5; i++) 67 i2c_write_start_seq(); 68 if (ret != 0) 69 printf("[ERROR] i2c abort failed after %d bytes (0x%02x)\n", 70 nbr_read, last); 71 72 return ret; 73 } 74