1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * drivers/net/wan/slic_ds26522.c
4 *
5 * Copyright (C) 2016 Freescale Semiconductor, Inc.
6 *
7 * Author:Zhao Qiang<qiang.zhao@nxp.com>
8 */
9
10 #include <linux/bitrev.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/kthread.h>
16 #include <linux/spi/spi.h>
17 #include <linux/wait.h>
18 #include <linux/param.h>
19 #include <linux/delay.h>
20 #include <linux/of.h>
21 #include <linux/of_address.h>
22 #include <linux/io.h>
23 #include "slic_ds26522.h"
24
25 #define SLIC_TRANS_LEN 1
26 #define SLIC_TWO_LEN 2
27 #define SLIC_THREE_LEN 3
28
29 static struct spi_device *g_spi;
30
31 MODULE_LICENSE("GPL");
32 MODULE_AUTHOR("Zhao Qiang<B45475@freescale.com>");
33
34 /* the read/write format of address is
35 * w/r|A13|A12|A11|A10|A9|A8|A7|A6|A5|A4|A3|A2|A1|A0|x
36 */
slic_write(struct spi_device * spi,u16 addr,u8 data)37 static void slic_write(struct spi_device *spi, u16 addr,
38 u8 data)
39 {
40 u8 temp[3];
41
42 addr = bitrev16(addr) >> 1;
43 data = bitrev8(data);
44 temp[0] = (u8)((addr >> 8) & 0x7f);
45 temp[1] = (u8)(addr & 0xfe);
46 temp[2] = data;
47
48 /* write spi addr and value */
49 spi_write(spi, &temp[0], SLIC_THREE_LEN);
50 }
51
slic_read(struct spi_device * spi,u16 addr)52 static u8 slic_read(struct spi_device *spi, u16 addr)
53 {
54 u8 temp[2];
55 u8 data;
56
57 addr = bitrev16(addr) >> 1;
58 temp[0] = (u8)(((addr >> 8) & 0x7f) | 0x80);
59 temp[1] = (u8)(addr & 0xfe);
60
61 spi_write_then_read(spi, &temp[0], SLIC_TWO_LEN, &data,
62 SLIC_TRANS_LEN);
63
64 data = bitrev8(data);
65 return data;
66 }
67
get_slic_product_code(struct spi_device * spi)68 static bool get_slic_product_code(struct spi_device *spi)
69 {
70 u8 device_id;
71
72 device_id = slic_read(spi, DS26522_IDR_ADDR);
73 if ((device_id & 0xf8) == 0x68)
74 return true;
75 else
76 return false;
77 }
78
ds26522_e1_spec_config(struct spi_device * spi)79 static void ds26522_e1_spec_config(struct spi_device *spi)
80 {
81 /* Receive E1 Mode, Framer Disabled */
82 slic_write(spi, DS26522_RMMR_ADDR, DS26522_RMMR_E1);
83
84 /* Transmit E1 Mode, Framer Disable */
85 slic_write(spi, DS26522_TMMR_ADDR, DS26522_TMMR_E1);
86
87 /* Receive E1 Mode Framer Enable */
88 slic_write(spi, DS26522_RMMR_ADDR,
89 slic_read(spi, DS26522_RMMR_ADDR) | DS26522_RMMR_FRM_EN);
90
91 /* Transmit E1 Mode Framer Enable */
92 slic_write(spi, DS26522_TMMR_ADDR,
93 slic_read(spi, DS26522_TMMR_ADDR) | DS26522_TMMR_FRM_EN);
94
95 /* RCR1, receive E1 B8zs & ESF */
96 slic_write(spi, DS26522_RCR1_ADDR,
97 DS26522_RCR1_E1_HDB3 | DS26522_RCR1_E1_CCS);
98
99 /* RSYSCLK=2.048MHz, RSYNC-Output */
100 slic_write(spi, DS26522_RIOCR_ADDR,
101 DS26522_RIOCR_2048KHZ | DS26522_RIOCR_RSIO_OUT);
102
103 /* TCR1 Transmit E1 b8zs */
104 slic_write(spi, DS26522_TCR1_ADDR, DS26522_TCR1_TB8ZS);
105
106 /* TSYSCLK=2.048MHz, TSYNC-Output */
107 slic_write(spi, DS26522_TIOCR_ADDR,
108 DS26522_TIOCR_2048KHZ | DS26522_TIOCR_TSIO_OUT);
109
110 /* Set E1TAF */
111 slic_write(spi, DS26522_E1TAF_ADDR, DS26522_E1TAF_DEFAULT);
112
113 /* Set E1TNAF register */
114 slic_write(spi, DS26522_E1TNAF_ADDR, DS26522_E1TNAF_DEFAULT);
115
116 /* Receive E1 Mode Framer Enable & init Done */
117 slic_write(spi, DS26522_RMMR_ADDR, slic_read(spi, DS26522_RMMR_ADDR) |
118 DS26522_RMMR_INIT_DONE);
119
120 /* Transmit E1 Mode Framer Enable & init Done */
121 slic_write(spi, DS26522_TMMR_ADDR, slic_read(spi, DS26522_TMMR_ADDR) |
122 DS26522_TMMR_INIT_DONE);
123
124 /* Configure LIU E1 mode */
125 slic_write(spi, DS26522_LTRCR_ADDR, DS26522_LTRCR_E1);
126
127 /* E1 Mode default 75 ohm w/Transmit Impedance Matlinking */
128 slic_write(spi, DS26522_LTITSR_ADDR,
129 DS26522_LTITSR_TLIS_75OHM | DS26522_LTITSR_LBOS_75OHM);
130
131 /* E1 Mode default 75 ohm Long Haul w/Receive Impedance Matlinking */
132 slic_write(spi, DS26522_LRISMR_ADDR,
133 DS26522_LRISMR_75OHM | DS26522_LRISMR_MAX);
134
135 /* Enable Transmit output */
136 slic_write(spi, DS26522_LMCR_ADDR, DS26522_LMCR_TE);
137 }
138
slic_ds26522_init_configure(struct spi_device * spi)139 static int slic_ds26522_init_configure(struct spi_device *spi)
140 {
141 u16 addr;
142
143 /* set clock */
144 slic_write(spi, DS26522_GTCCR_ADDR, DS26522_GTCCR_BPREFSEL_REFCLKIN |
145 DS26522_GTCCR_BFREQSEL_2048KHZ |
146 DS26522_GTCCR_FREQSEL_2048KHZ);
147 slic_write(spi, DS26522_GTCR2_ADDR, DS26522_GTCR2_TSSYNCOUT);
148 slic_write(spi, DS26522_GFCR_ADDR, DS26522_GFCR_BPCLK_2048KHZ);
149
150 /* set gtcr */
151 slic_write(spi, DS26522_GTCR1_ADDR, DS26522_GTCR1);
152
153 /* Global LIU Software Reset Register */
154 slic_write(spi, DS26522_GLSRR_ADDR, DS26522_GLSRR_RESET);
155
156 /* Global Framer and BERT Software Reset Register */
157 slic_write(spi, DS26522_GFSRR_ADDR, DS26522_GFSRR_RESET);
158
159 usleep_range(100, 120);
160
161 slic_write(spi, DS26522_GLSRR_ADDR, DS26522_GLSRR_NORMAL);
162 slic_write(spi, DS26522_GFSRR_ADDR, DS26522_GFSRR_NORMAL);
163
164 /* Perform RX/TX SRESET,Reset receiver */
165 slic_write(spi, DS26522_RMMR_ADDR, DS26522_RMMR_SFTRST);
166
167 /* Reset tranceiver */
168 slic_write(spi, DS26522_TMMR_ADDR, DS26522_TMMR_SFTRST);
169
170 usleep_range(100, 120);
171
172 /* Zero all Framer Registers */
173 for (addr = DS26522_RF_ADDR_START; addr <= DS26522_RF_ADDR_END;
174 addr++)
175 slic_write(spi, addr, 0);
176
177 for (addr = DS26522_TF_ADDR_START; addr <= DS26522_TF_ADDR_END;
178 addr++)
179 slic_write(spi, addr, 0);
180
181 for (addr = DS26522_LIU_ADDR_START; addr <= DS26522_LIU_ADDR_END;
182 addr++)
183 slic_write(spi, addr, 0);
184
185 for (addr = DS26522_BERT_ADDR_START; addr <= DS26522_BERT_ADDR_END;
186 addr++)
187 slic_write(spi, addr, 0);
188
189 /* setup ds26522 for E1 specification */
190 ds26522_e1_spec_config(spi);
191
192 slic_write(spi, DS26522_GTCR1_ADDR, 0x00);
193
194 return 0;
195 }
196
slic_ds26522_remove(struct spi_device * spi)197 static void slic_ds26522_remove(struct spi_device *spi)
198 {
199 pr_info("DS26522 module uninstalled\n");
200 }
201
slic_ds26522_probe(struct spi_device * spi)202 static int slic_ds26522_probe(struct spi_device *spi)
203 {
204 int ret = 0;
205
206 g_spi = spi;
207 spi->bits_per_word = 8;
208
209 if (!get_slic_product_code(spi))
210 return ret;
211
212 ret = slic_ds26522_init_configure(spi);
213 if (ret == 0)
214 pr_info("DS26522 cs%d configured\n", spi_get_chipselect(spi, 0));
215
216 return ret;
217 }
218
219 static const struct spi_device_id slic_ds26522_id[] = {
220 { .name = "ds26522" },
221 { /* sentinel */ },
222 };
223 MODULE_DEVICE_TABLE(spi, slic_ds26522_id);
224
225 static const struct of_device_id slic_ds26522_match[] = {
226 {
227 .compatible = "maxim,ds26522",
228 },
229 {},
230 };
231 MODULE_DEVICE_TABLE(of, slic_ds26522_match);
232
233 static struct spi_driver slic_ds26522_driver = {
234 .driver = {
235 .name = "ds26522",
236 .bus = &spi_bus_type,
237 .of_match_table = slic_ds26522_match,
238 },
239 .probe = slic_ds26522_probe,
240 .remove = slic_ds26522_remove,
241 .id_table = slic_ds26522_id,
242 };
243
244 module_spi_driver(slic_ds26522_driver);
245