drivers/raw/ifpga/base/opae_at24_eeprom.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2019 Intel Corporation
   3  */
   4
   5 #include "opae_osdep.h"
   6 #include "opae_i2c.h"
   7 #include "opae_at24_eeprom.h"
   8
   9 #define AT24_READ_RETRY 10
  10
  11 static int at24_eeprom_read_and_try(struct altera_i2c_dev *dev,
  12                 unsigned int slave_addr,
  13                 u32 offset, u8 *buf, u32 len)
  14 {
  15         int i;
  16         int ret = 0;
  17
  18         for (i = 0; i < AT24_READ_RETRY; i++) {
  19                 ret = i2c_read16(dev, slave_addr, offset,
  20                                 buf, len);
  21                 if (ret == 0)
  22                         break;
  23
  24                 opae_udelay(100);
  25         }
  26
  27         return ret;
  28 }
  29
  30 int at24_eeprom_read(struct altera_i2c_dev *dev, unsigned int slave_addr,
  31                 u32 offset, u8 *buf, int count)
  32 {
  33         int len;
  34         int status;
  35         int read_count = 0;
  36
  37         if (!count)
  38                 return count;
  39
  40         if (count > AT24C512_IO_LIMIT)
  41                 len = AT24C512_IO_LIMIT;
  42         else
  43                 len = count;
  44
  45         while (count) {
  46                 status = at24_eeprom_read_and_try(dev, slave_addr, offset,
  47                                 buf, len);
  48                 if (status)
  49                         break;
  50
  51                 buf += len;
  52                 offset += len;
  53                 count -= len;
  54                 read_count += len;
  55         }
  56
  57         return read_count;
  58 }
  59
  60 int at24_eeprom_write(struct altera_i2c_dev *dev, unsigned int slave_addr,
  61                 u32 offset, u8 *buf, int count)
  62 {
  63         int len;
  64         int status;
  65         int write_count = 0;
  66
  67         if (!count)
  68                 return count;
  69
  70         if (count > AT24C512_PAGE_SIZE)
  71                 len = AT24C512_PAGE_SIZE;
  72         else
  73                 len = count;
  74
  75         while (count) {
  76                 status = i2c_write16(dev, slave_addr, offset, buf, len);
  77                 if (status)
  78                         break;
  79
  80                 buf += len;
  81                 offset += len;
  82                 count -= len;
  83                 write_count += len;
  84         }
  85
  86         return write_count;
  87 }