drivers/misc/i2c_eeprom.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (c) 2014 Google, Inc
   4  */
   5
   6 #include <common.h>
   7 #include <eeprom.h>
   8 #include <linux/err.h>
   9 #include <linux/kernel.h>
  10 #include <dm.h>
  11 #include <i2c.h>
  12 #include <i2c_eeprom.h>
  13
  14 int i2c_eeprom_read(struct udevice *dev, int offset, uint8_t *buf, int size)
  15 {
  16         const struct i2c_eeprom_ops *ops = device_get_ops(dev);
  17
  18         if (!ops->read)
  19                 return -ENOSYS;
  20
  21         return ops->read(dev, offset, buf, size);
  22 }
  23
  24 int i2c_eeprom_write(struct udevice *dev, int offset, uint8_t *buf, int size)
  25 {
  26         const struct i2c_eeprom_ops *ops = device_get_ops(dev);
  27
  28         if (!ops->write)
  29                 return -ENOSYS;
  30
  31         return ops->write(dev, offset, buf, size);
  32 }
  33
  34 static int i2c_eeprom_std_read(struct udevice *dev, int offset, uint8_t *buf,
  35                                int size)
  36 {
  37         return dm_i2c_read(dev, offset, buf, size);
  38 }
  39
  40 static int i2c_eeprom_std_write(struct udevice *dev, int offset,
  41                                 const uint8_t *buf, int size)
  42 {
  43         struct i2c_eeprom *priv = dev_get_priv(dev);
  44         int ret;
  45
  46         while (size > 0) {
  47                 int write_size = min_t(int, size, priv->pagesize);
  48
  49                 ret = dm_i2c_write(dev, offset, buf, write_size);
  50                 if (ret)
  51                         return ret;
  52
  53                 offset += write_size;
  54                 buf += write_size;
  55                 size -= write_size;
  56
  57                 udelay(10000);
  58         }
  59
  60         return 0;
  61 }
  62
  63 static const struct i2c_eeprom_ops i2c_eeprom_std_ops = {
  64         .read   = i2c_eeprom_std_read,
  65         .write  = i2c_eeprom_std_write,
  66 };
  67
  68 static int i2c_eeprom_std_ofdata_to_platdata(struct udevice *dev)
  69 {
  70         struct i2c_eeprom *priv = dev_get_priv(dev);
  71         u64 data = dev_get_driver_data(dev);
  72         u32 pagesize;
  73
  74         if (dev_read_u32(dev, "pagesize", &pagesize) == 0) {
  75                 priv->pagesize = pagesize;
  76                 return 0;
  77         }
  78
  79         /* 6 bit -> page size of up to 2^63 (should be sufficient) */
  80         priv->pagewidth = data & 0x3F;
  81         priv->pagesize = (1 << priv->pagewidth);
  82
  83         return 0;
  84 }
  85
  86 static int i2c_eeprom_std_probe(struct udevice *dev)
  87 {
  88         u8 test_byte;
  89         int ret;
  90
  91         /* Verify that the chip is functional */
  92         ret = i2c_eeprom_read(dev, 0, &test_byte, 1);
  93         if (ret)
  94                 return -ENODEV;
  95
  96         return 0;
  97 }
  98
  99 static const struct udevice_id i2c_eeprom_std_ids[] = {
 100         { .compatible = "i2c-eeprom", .data = 0 },
 101         { .compatible = "microchip,24aa02e48", .data = 3 },
 102         { .compatible = "atmel,24c01a", .data = 3 },
 103         { .compatible = "atmel,24c02", .data = 3 },
 104         { .compatible = "atmel,24c04", .data = 4 },
 105         { .compatible = "atmel,24c08", .data = 4 },
 106         { .compatible = "atmel,24c08a", .data = 4 },
 107         { .compatible = "atmel,24c16a", .data = 4 },
 108         { .compatible = "atmel,24mac402", .data = 4 },
 109         { .compatible = "atmel,24c32", .data = 5 },
 110         { .compatible = "atmel,24c64", .data = 5 },
 111         { .compatible = "atmel,24c128", .data = 6 },
 112         { .compatible = "atmel,24c256", .data = 6 },
 113         { .compatible = "atmel,24c512", .data = 6 },
 114         { }
 115 };
 116
 117 U_BOOT_DRIVER(i2c_eeprom_std) = {
 118         .name                   = "i2c_eeprom",
 119         .id                     = UCLASS_I2C_EEPROM,
 120         .of_match               = i2c_eeprom_std_ids,
 121         .probe                  = i2c_eeprom_std_probe,
 122         .ofdata_to_platdata     = i2c_eeprom_std_ofdata_to_platdata,
 123         .priv_auto_alloc_size   = sizeof(struct i2c_eeprom),
 124         .ops                    = &i2c_eeprom_std_ops,
 125 };
 126
 127 UCLASS_DRIVER(i2c_eeprom) = {
 128         .id             = UCLASS_I2C_EEPROM,
 129         .name           = "i2c_eeprom",
 130 };