1// SPDX-License-Identifier: GPL-2.0
2/******************************************************************************
3 * rtl871x_eeprom.c
4 *
5 * Copyright(c) 2007 - 2010 Realtek Corporation. All rights reserved.
6 * Linux device driver for RTL8192SU
7 *
8 * Modifications for inclusion into the Linux staging tree are
9 * Copyright(c) 2010 Larry Finger. All rights reserved.
10 *
11 * Contact information:
12 * WLAN FAE <wlanfae@realtek.com>
13 * Larry Finger <Larry.Finger@lwfinger.net>
14 *
15 ******************************************************************************/
16
17#define _RTL871X_EEPROM_C_
18
19#include "osdep_service.h"
20#include "drv_types.h"
21
22static void up_clk(struct _adapter *padapter, u16 *x)
23{
24	*x = *x | _EESK;
25	r8712_write8(padapter, EE_9346CR, (u8)*x);
26	udelay(CLOCK_RATE);
27}
28
29static void down_clk(struct _adapter *padapter, u16 *x)
30{
31	*x = *x & ~_EESK;
32	r8712_write8(padapter, EE_9346CR, (u8)*x);
33	udelay(CLOCK_RATE);
34}
35
36static void shift_out_bits(struct _adapter *padapter, u16 data, u16 count)
37{
38	u16 x, mask;
39
40	if (padapter->surprise_removed)
41		goto out;
42	mask = 0x01 << (count - 1);
43	x = r8712_read8(padapter, EE_9346CR);
44	x &= ~(_EEDO | _EEDI);
45	do {
46		x &= ~_EEDI;
47		if (data & mask)
48			x |= _EEDI;
49		if (padapter->surprise_removed)
50			goto out;
51		r8712_write8(padapter, EE_9346CR, (u8)x);
52		udelay(CLOCK_RATE);
53		up_clk(padapter, &x);
54		down_clk(padapter, &x);
55		mask >>= 1;
56	} while (mask);
57	if (padapter->surprise_removed)
58		goto out;
59	x &= ~_EEDI;
60	r8712_write8(padapter, EE_9346CR, (u8)x);
61out:;
62}
63
64static u16 shift_in_bits(struct _adapter *padapter)
65{
66	u16 x, d = 0, i;
67
68	if (padapter->surprise_removed)
69		goto out;
70	x = r8712_read8(padapter, EE_9346CR);
71	x &= ~(_EEDO | _EEDI);
72	d = 0;
73	for (i = 0; i < 16; i++) {
74		d <<= 1;
75		up_clk(padapter, &x);
76		if (padapter->surprise_removed)
77			goto out;
78		x = r8712_read8(padapter, EE_9346CR);
79		x &= ~(_EEDI);
80		if (x & _EEDO)
81			d |= 1;
82		down_clk(padapter, &x);
83	}
84out:
85	return d;
86}
87
88static void standby(struct _adapter *padapter)
89{
90	u8   x;
91
92	x = r8712_read8(padapter, EE_9346CR);
93	x &= ~(_EECS | _EESK);
94	r8712_write8(padapter, EE_9346CR, x);
95	udelay(CLOCK_RATE);
96	x |= _EECS;
97	r8712_write8(padapter, EE_9346CR, x);
98	udelay(CLOCK_RATE);
99}
100
101static u16 wait_eeprom_cmd_done(struct _adapter *padapter)
102{
103	u8	x;
104	u16	i;
105
106	standby(padapter);
107	for (i = 0; i < 200; i++) {
108		x = r8712_read8(padapter, EE_9346CR);
109		if (x & _EEDO)
110			return true;
111		udelay(CLOCK_RATE);
112	}
113	return false;
114}
115
116static void eeprom_clean(struct _adapter *padapter)
117{
118	u16 x;
119
120	if (padapter->surprise_removed)
121		return;
122	x = r8712_read8(padapter, EE_9346CR);
123	if (padapter->surprise_removed)
124		return;
125	x &= ~(_EECS | _EEDI);
126	r8712_write8(padapter, EE_9346CR, (u8)x);
127	if (padapter->surprise_removed)
128		return;
129	up_clk(padapter, &x);
130	if (padapter->surprise_removed)
131		return;
132	down_clk(padapter, &x);
133}
134
135void r8712_eeprom_write16(struct _adapter *padapter, u16 reg, u16 data)
136{
137	u8 x;
138	u8 tmp8_ori, tmp8_new, tmp8_clk_ori, tmp8_clk_new;
139
140	tmp8_ori = r8712_read8(padapter, 0x102502f1);
141	tmp8_new = tmp8_ori & 0xf7;
142	if (tmp8_ori != tmp8_new)
143		r8712_write8(padapter, 0x102502f1, tmp8_new);
144	tmp8_clk_ori = r8712_read8(padapter, 0x10250003);
145	tmp8_clk_new = tmp8_clk_ori | 0x20;
146	if (tmp8_clk_new != tmp8_clk_ori)
147		r8712_write8(padapter, 0x10250003, tmp8_clk_new);
148	x = r8712_read8(padapter, EE_9346CR);
149	x &= ~(_EEDI | _EEDO | _EESK | _EEM0);
150	x |= _EEM1 | _EECS;
151	r8712_write8(padapter, EE_9346CR, x);
152	shift_out_bits(padapter, EEPROM_EWEN_OPCODE, 5);
153	if (padapter->eeprom_address_size == 8)	/*CF+ and SDIO*/
154		shift_out_bits(padapter, 0, 6);
155	else	/* USB */
156		shift_out_bits(padapter, 0, 4);
157	standby(padapter);
158	/* Erase this particular word.  Write the erase opcode and register
159	 * number in that order. The opcode is 3bits in length; reg is 6
160	 * bits long.
161	 */
162	standby(padapter);
163	/* write the new word to the EEPROM
164	 * send the write opcode the EEPORM
165	 */
166	shift_out_bits(padapter, EEPROM_WRITE_OPCODE, 3);
167	/* select which word in the EEPROM that we are writing to. */
168	shift_out_bits(padapter, reg, padapter->eeprom_address_size);
169	/* write the data to the selected EEPROM word. */
170	shift_out_bits(padapter, data, 16);
171	if (wait_eeprom_cmd_done(padapter)) {
172		standby(padapter);
173		shift_out_bits(padapter, EEPROM_EWDS_OPCODE, 5);
174		shift_out_bits(padapter, reg, 4);
175		eeprom_clean(padapter);
176	}
177	if (tmp8_clk_new != tmp8_clk_ori)
178		r8712_write8(padapter, 0x10250003, tmp8_clk_ori);
179	if (tmp8_new != tmp8_ori)
180		r8712_write8(padapter, 0x102502f1, tmp8_ori);
181}
182
183u16 r8712_eeprom_read16(struct _adapter *padapter, u16 reg) /*ReadEEprom*/
184{
185	u16 x;
186	u16 data = 0;
187	u8 tmp8_ori, tmp8_new, tmp8_clk_ori, tmp8_clk_new;
188
189	tmp8_ori = r8712_read8(padapter, 0x102502f1);
190	tmp8_new = tmp8_ori & 0xf7;
191	if (tmp8_ori != tmp8_new)
192		r8712_write8(padapter, 0x102502f1, tmp8_new);
193	tmp8_clk_ori = r8712_read8(padapter, 0x10250003);
194	tmp8_clk_new = tmp8_clk_ori | 0x20;
195	if (tmp8_clk_new != tmp8_clk_ori)
196		r8712_write8(padapter, 0x10250003, tmp8_clk_new);
197	if (padapter->surprise_removed)
198		goto out;
199	/* select EEPROM, reset bits, set _EECS */
200	x = r8712_read8(padapter, EE_9346CR);
201	if (padapter->surprise_removed)
202		goto out;
203	x &= ~(_EEDI | _EEDO | _EESK | _EEM0);
204	x |= _EEM1 | _EECS;
205	r8712_write8(padapter, EE_9346CR, (unsigned char)x);
206	/* write the read opcode and register number in that order
207	 * The opcode is 3bits in length, reg is 6 bits long
208	 */
209	shift_out_bits(padapter, EEPROM_READ_OPCODE, 3);
210	shift_out_bits(padapter, reg, padapter->eeprom_address_size);
211	/* Now read the data (16 bits) in from the selected EEPROM word */
212	data = shift_in_bits(padapter);
213	eeprom_clean(padapter);
214out:
215	if (tmp8_clk_new != tmp8_clk_ori)
216		r8712_write8(padapter, 0x10250003, tmp8_clk_ori);
217	if (tmp8_new != tmp8_ori)
218		r8712_write8(padapter, 0x102502f1, tmp8_ori);
219	return data;
220}
221