1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright(c) 2008 - 2010 Realtek Corporation. All rights reserved.
4 *
5 * Based on the r8180 driver, which is:
6 * Copyright 2004-2005 Andrea Merello <andrea.merello@gmail.com>, et al.
7 *
8 * Contact Information: wlanfae <wlanfae@realtek.com>
9 */
10#include "rtl_core.h"
11#include "rtl_eeprom.h"
12
13static void _rtl92e_gpio_write_bit(struct net_device *dev, int no, bool val)
14{
15 u8 reg = rtl92e_readb(dev, x: EPROM_CMD);
16
17 if (val)
18 reg |= 1 << no;
19 else
20 reg &= ~(1 << no);
21
22 rtl92e_writeb(dev, x: EPROM_CMD, y: reg);
23 udelay(EPROM_DELAY);
24}
25
26static bool _rtl92e_gpio_get_bit(struct net_device *dev, int no)
27{
28 u8 reg = rtl92e_readb(dev, x: EPROM_CMD);
29
30 return (reg >> no) & 0x1;
31}
32
33static void _rtl92e_eeprom_ck_cycle(struct net_device *dev)
34{
35 _rtl92e_gpio_write_bit(dev, EPROM_CK_BIT, val: 1);
36 _rtl92e_gpio_write_bit(dev, EPROM_CK_BIT, val: 0);
37}
38
39static u16 _rtl92e_eeprom_xfer(struct net_device *dev, u16 data, int tx_len)
40{
41 u16 ret = 0;
42 int rx_len = 16;
43
44 _rtl92e_gpio_write_bit(dev, EPROM_CS_BIT, val: 1);
45 _rtl92e_eeprom_ck_cycle(dev);
46
47 while (tx_len--) {
48 _rtl92e_gpio_write_bit(dev, EPROM_W_BIT,
49 val: (data >> tx_len) & 0x1);
50 _rtl92e_eeprom_ck_cycle(dev);
51 }
52
53 _rtl92e_gpio_write_bit(dev, EPROM_W_BIT, val: 0);
54
55 while (rx_len--) {
56 _rtl92e_eeprom_ck_cycle(dev);
57 ret |= _rtl92e_gpio_get_bit(dev, EPROM_R_BIT) << rx_len;
58 }
59
60 _rtl92e_gpio_write_bit(dev, EPROM_CS_BIT, val: 0);
61 _rtl92e_eeprom_ck_cycle(dev);
62
63 return ret;
64}
65
66u32 rtl92e_eeprom_read(struct net_device *dev, u32 addr)
67{
68 struct r8192_priv *priv = rtllib_priv(dev);
69 u32 ret = 0;
70
71 rtl92e_writeb(dev, x: EPROM_CMD,
72 y: (EPROM_CMD_PROGRAM << EPROM_CMD_OPERATING_MODE_SHIFT));
73 udelay(EPROM_DELAY);
74
75 /* EEPROM is configured as x16 */
76 if (priv->epromtype == EEPROM_93C56)
77 ret = _rtl92e_eeprom_xfer(dev, data: (addr & 0xFF) | (0x6 << 8), tx_len: 11);
78 else
79 ret = _rtl92e_eeprom_xfer(dev, data: (addr & 0x3F) | (0x6 << 6), tx_len: 9);
80
81 rtl92e_writeb(dev, x: EPROM_CMD,
82 y: (EPROM_CMD_NORMAL << EPROM_CMD_OPERATING_MODE_SHIFT));
83 return ret;
84}
85

source code of linux/drivers/staging/rtl8192e/rtl8192e/rtl_eeprom.c