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 *dev; 17 dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET); 18 udelay(DELAY_ABORT_SEQ); 19 out_8(&dev->cr, (I2C_CR_MEN | I2C_CR_MSTA)); 20 udelay(DELAY_ABORT_SEQ); 21 out_8(&dev->cr, (I2C_CR_MEN)); 22 } 23 24 int i2c_make_abort(void) 25 { 26 struct fsl_i2c *dev; 27 dev = (struct fsl_i2c *) (CONFIG_SYS_IMMR + CONFIG_SYS_I2C_OFFSET); 28 uchar last; 29 int nbr_read = 0; 30 int i = 0; 31 int ret = 0; 32 33 /* wait after each operation to finsh with a delay */ 34 out_8(&dev->cr, (I2C_CR_MSTA)); 35 udelay(DELAY_ABORT_SEQ); 36 out_8(&dev->cr, (I2C_CR_MEN | I2C_CR_MSTA)); 37 udelay(DELAY_ABORT_SEQ); 38 in_8(&dev->dr); 39 udelay(DELAY_ABORT_SEQ); 40 last = in_8(&dev->dr); 41 nbr_read++; 42 43 /* 44 * do read until the last bit is 1, but stop if the full eeprom is 45 * read. 46 */ 47 while (((last & 0x01) != 0x01) && 48 (nbr_read < CONFIG_SYS_IVM_EEPROM_MAX_LEN)) { 49 udelay(DELAY_ABORT_SEQ); 50 last = in_8(&dev->dr); 51 nbr_read++; 52 } 53 if ((last & 0x01) != 0x01) 54 ret = -2; 55 if ((last != 0xff) || (nbr_read > 1)) 56 printf("[INFO] i2c abort after %d bytes (0x%02x)\n", 57 nbr_read, last); 58 udelay(DELAY_ABORT_SEQ); 59 out_8(&dev->cr, (I2C_CR_MEN)); 60 udelay(DELAY_ABORT_SEQ); 61 /* clear status reg */ 62 out_8(&dev->sr, 0); 63 64 for (i = 0; i < 5; i++) 65 i2c_write_start_seq(); 66 if (ret != 0) 67 printf("[ERROR] i2c abort failed after %d bytes (0x%02x)\n", 68 nbr_read, last); 69 70 return ret; 71 } 72