1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 Mantis PCI bridge driver
4
5 Copyright (C) Manu Abraham (abraham.manu@gmail.com)
6
7 */
8
9 #include <asm/io.h>
10 #include <linux/ioport.h>
11 #include <linux/pci.h>
12 #include <linux/i2c.h>
13
14 #include <media/dmxdev.h>
15 #include <media/dvbdev.h>
16 #include <media/dvb_demux.h>
17 #include <media/dvb_frontend.h>
18 #include <media/dvb_net.h>
19
20 #include "mantis_common.h"
21 #include "mantis_reg.h"
22 #include "mantis_i2c.h"
23
24 #define TRIALS 10000
25
mantis_i2c_read(struct mantis_pci * mantis,const struct i2c_msg * msg)26 static int mantis_i2c_read(struct mantis_pci *mantis, const struct i2c_msg *msg)
27 {
28 u32 rxd, i, stat, trials;
29
30 dprintk(MANTIS_INFO, 0, " %s: Address=[0x%02x] <R>[ ",
31 __func__, msg->addr);
32
33 for (i = 0; i < msg->len; i++) {
34 rxd = (msg->addr << 25) | (1 << 24)
35 | MANTIS_I2C_RATE_3
36 | MANTIS_I2C_STOP
37 | MANTIS_I2C_PGMODE;
38
39 if (i == (msg->len - 1))
40 rxd &= ~MANTIS_I2C_STOP;
41
42 mmwrite(MANTIS_INT_I2CDONE, MANTIS_INT_STAT);
43 mmwrite(rxd, MANTIS_I2CDATA_CTL);
44
45 /* wait for xfer completion */
46 for (trials = 0; trials < TRIALS; trials++) {
47 stat = mmread(MANTIS_INT_STAT);
48 if (stat & MANTIS_INT_I2CDONE)
49 break;
50 }
51
52 dprintk(MANTIS_TMG, 0, "I2CDONE: trials=%d\n", trials);
53
54 /* wait for xfer completion */
55 for (trials = 0; trials < TRIALS; trials++) {
56 stat = mmread(MANTIS_INT_STAT);
57 if (stat & MANTIS_INT_I2CRACK)
58 break;
59 }
60
61 dprintk(MANTIS_TMG, 0, "I2CRACK: trials=%d\n", trials);
62
63 rxd = mmread(MANTIS_I2CDATA_CTL);
64 msg->buf[i] = (u8)((rxd >> 8) & 0xFF);
65 dprintk(MANTIS_INFO, 0, "%02x ", msg->buf[i]);
66 }
67 dprintk(MANTIS_INFO, 0, "]\n");
68
69 return 0;
70 }
71
mantis_i2c_write(struct mantis_pci * mantis,const struct i2c_msg * msg)72 static int mantis_i2c_write(struct mantis_pci *mantis, const struct i2c_msg *msg)
73 {
74 int i;
75 u32 txd = 0, stat, trials;
76
77 dprintk(MANTIS_INFO, 0, " %s: Address=[0x%02x] <W>[ ",
78 __func__, msg->addr);
79
80 for (i = 0; i < msg->len; i++) {
81 dprintk(MANTIS_INFO, 0, "%02x ", msg->buf[i]);
82 txd = (msg->addr << 25) | (msg->buf[i] << 8)
83 | MANTIS_I2C_RATE_3
84 | MANTIS_I2C_STOP
85 | MANTIS_I2C_PGMODE;
86
87 if (i == (msg->len - 1))
88 txd &= ~MANTIS_I2C_STOP;
89
90 mmwrite(MANTIS_INT_I2CDONE, MANTIS_INT_STAT);
91 mmwrite(txd, MANTIS_I2CDATA_CTL);
92
93 /* wait for xfer completion */
94 for (trials = 0; trials < TRIALS; trials++) {
95 stat = mmread(MANTIS_INT_STAT);
96 if (stat & MANTIS_INT_I2CDONE)
97 break;
98 }
99
100 dprintk(MANTIS_TMG, 0, "I2CDONE: trials=%d\n", trials);
101
102 /* wait for xfer completion */
103 for (trials = 0; trials < TRIALS; trials++) {
104 stat = mmread(MANTIS_INT_STAT);
105 if (stat & MANTIS_INT_I2CRACK)
106 break;
107 }
108
109 dprintk(MANTIS_TMG, 0, "I2CRACK: trials=%d\n", trials);
110 }
111 dprintk(MANTIS_INFO, 0, "]\n");
112
113 return 0;
114 }
115
mantis_i2c_xfer(struct i2c_adapter * adapter,struct i2c_msg * msgs,int num)116 static int mantis_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num)
117 {
118 int ret = 0, i = 0, trials;
119 u32 stat, data, txd;
120 struct mantis_pci *mantis;
121 struct mantis_hwconfig *config;
122
123 mantis = i2c_get_adapdata(adapter);
124 BUG_ON(!mantis);
125 config = mantis->hwconfig;
126 BUG_ON(!config);
127
128 dprintk(MANTIS_DEBUG, 1, "Messages:%d", num);
129 mutex_lock(&mantis->i2c_lock);
130
131 while (i < num) {
132 /* Byte MODE */
133 if ((config->i2c_mode & MANTIS_BYTE_MODE) &&
134 ((i + 1) < num) &&
135 (msgs[i].len < 2) &&
136 (msgs[i + 1].len < 2) &&
137 (msgs[i + 1].flags & I2C_M_RD)) {
138
139 dprintk(MANTIS_DEBUG, 0, " Byte MODE:\n");
140
141 /* Read operation */
142 txd = msgs[i].addr << 25 | (0x1 << 24)
143 | (msgs[i].buf[0] << 16)
144 | MANTIS_I2C_RATE_3;
145
146 mmwrite(txd, MANTIS_I2CDATA_CTL);
147 /* wait for xfer completion */
148 for (trials = 0; trials < TRIALS; trials++) {
149 stat = mmread(MANTIS_INT_STAT);
150 if (stat & MANTIS_INT_I2CDONE)
151 break;
152 }
153
154 /* check for xfer completion */
155 if (stat & MANTIS_INT_I2CDONE) {
156 /* check xfer was acknowledged */
157 if (stat & MANTIS_INT_I2CRACK) {
158 data = mmread(MANTIS_I2CDATA_CTL);
159 msgs[i + 1].buf[0] = (data >> 8) & 0xff;
160 dprintk(MANTIS_DEBUG, 0, " Byte <%d> RXD=0x%02x [%02x]\n", 0x0, data, msgs[i + 1].buf[0]);
161 } else {
162 /* I/O error */
163 dprintk(MANTIS_ERROR, 1, " I/O error, LINE:%d", __LINE__);
164 ret = -EIO;
165 break;
166 }
167 } else {
168 /* I/O error */
169 dprintk(MANTIS_ERROR, 1, " I/O error, LINE:%d", __LINE__);
170 ret = -EIO;
171 break;
172 }
173 i += 2; /* Write/Read operation in one go */
174 }
175
176 if (i < num) {
177 if (msgs[i].flags & I2C_M_RD)
178 ret = mantis_i2c_read(mantis, &msgs[i]);
179 else
180 ret = mantis_i2c_write(mantis, &msgs[i]);
181
182 i++;
183 if (ret < 0)
184 goto bail_out;
185 }
186
187 }
188
189 mutex_unlock(&mantis->i2c_lock);
190
191 return num;
192
193 bail_out:
194 mutex_unlock(&mantis->i2c_lock);
195 return ret;
196 }
197
mantis_i2c_func(struct i2c_adapter * adapter)198 static u32 mantis_i2c_func(struct i2c_adapter *adapter)
199 {
200 return I2C_FUNC_SMBUS_EMUL;
201 }
202
203 static const struct i2c_algorithm mantis_algo = {
204 .master_xfer = mantis_i2c_xfer,
205 .functionality = mantis_i2c_func,
206 };
207
mantis_i2c_init(struct mantis_pci * mantis)208 int mantis_i2c_init(struct mantis_pci *mantis)
209 {
210 u32 intstat;
211 struct i2c_adapter *i2c_adapter = &mantis->adapter;
212 struct pci_dev *pdev = mantis->pdev;
213
214 init_waitqueue_head(&mantis->i2c_wq);
215 mutex_init(&mantis->i2c_lock);
216 strscpy(i2c_adapter->name, "Mantis I2C", sizeof(i2c_adapter->name));
217 i2c_set_adapdata(i2c_adapter, mantis);
218
219 i2c_adapter->owner = THIS_MODULE;
220 i2c_adapter->algo = &mantis_algo;
221 i2c_adapter->algo_data = NULL;
222 i2c_adapter->timeout = 500;
223 i2c_adapter->retries = 3;
224 i2c_adapter->dev.parent = &pdev->dev;
225
226 mantis->i2c_rc = i2c_add_adapter(i2c_adapter);
227 if (mantis->i2c_rc < 0)
228 return mantis->i2c_rc;
229
230 dprintk(MANTIS_DEBUG, 1, "Initializing I2C ..");
231
232 intstat = mmread(MANTIS_INT_STAT);
233 mmread(MANTIS_INT_MASK);
234 mmwrite(intstat, MANTIS_INT_STAT);
235 dprintk(MANTIS_DEBUG, 1, "Disabling I2C interrupt");
236 mantis_mask_ints(mantis, MANTIS_INT_I2CDONE);
237
238 return 0;
239 }
240 EXPORT_SYMBOL_GPL(mantis_i2c_init);
241
mantis_i2c_exit(struct mantis_pci * mantis)242 int mantis_i2c_exit(struct mantis_pci *mantis)
243 {
244 dprintk(MANTIS_DEBUG, 1, "Disabling I2C interrupt");
245 mantis_mask_ints(mantis, MANTIS_INT_I2CDONE);
246
247 dprintk(MANTIS_DEBUG, 1, "Removing I2C adapter");
248 i2c_del_adapter(&mantis->adapter);
249
250 return 0;
251 }
252 EXPORT_SYMBOL_GPL(mantis_i2c_exit);
253