xref: /linux/drivers/media/pci/ngene/ngene-i2c.c (revision e27a24210aa17b8a0cd462865130fe73afd7e001)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ngene-i2c.c: nGene PCIe bridge driver i2c functions
4  *
5  * Copyright (C) 2005-2007 Micronas
6  *
7  * Copyright (C) 2008-2009 Ralph Metzler <rjkm@metzlerbros.de>
8  *                         Modifications for new nGene firmware,
9  *                         support for EEPROM-copying,
10  *                         support for new dual DVB-S2 card prototype
11  */
12 
13 /* FIXME - some of these can probably be removed */
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/delay.h>
17 #include <linux/slab.h>
18 #include <linux/poll.h>
19 #include <linux/io.h>
20 #include <asm/div64.h>
21 #include <linux/pci.h>
22 #include <linux/pci_ids.h>
23 #include <linux/timer.h>
24 #include <linux/byteorder/generic.h>
25 #include <linux/firmware.h>
26 #include <linux/vmalloc.h>
27 
28 #include "ngene.h"
29 
30 /* Firmware command for i2c operations */
31 static int ngene_command_i2c_read(struct ngene *dev, u8 adr,
32 			   u8 *out, u8 outlen, u8 *in, u8 inlen, int flag)
33 {
34 	struct ngene_command com;
35 
36 	com.cmd.hdr.Opcode = CMD_I2C_READ;
37 	com.cmd.hdr.Length = outlen + 3;
38 	com.cmd.I2CRead.Device = adr << 1;
39 	memcpy(com.cmd.I2CRead.Data, out, outlen);
40 	com.cmd.I2CRead.Data[outlen] = inlen;
41 	com.cmd.I2CRead.Data[outlen + 1] = 0;
42 	com.in_len = outlen + 3;
43 	com.out_len = inlen + 1;
44 
45 	if (ngene_command(dev, &com) < 0)
46 		return -EIO;
47 
48 	if ((com.cmd.raw8[0] >> 1) != adr)
49 		return -EIO;
50 
51 	if (flag)
52 		memcpy(in, com.cmd.raw8, inlen + 1);
53 	else
54 		memcpy(in, com.cmd.raw8 + 1, inlen);
55 	return 0;
56 }
57 
58 static int ngene_command_i2c_write(struct ngene *dev, u8 adr,
59 				   u8 *out, u8 outlen)
60 {
61 	struct ngene_command com;
62 
63 
64 	com.cmd.hdr.Opcode = CMD_I2C_WRITE;
65 	com.cmd.hdr.Length = outlen + 1;
66 	com.cmd.I2CRead.Device = adr << 1;
67 	memcpy(com.cmd.I2CRead.Data, out, outlen);
68 	com.in_len = outlen + 1;
69 	com.out_len = 1;
70 
71 	if (ngene_command(dev, &com) < 0)
72 		return -EIO;
73 
74 	if (com.cmd.raw8[0] == 1)
75 		return -EIO;
76 
77 	return 0;
78 }
79 
80 static void ngene_i2c_set_bus(struct ngene *dev, int bus)
81 {
82 	if (!(dev->card_info->i2c_access & 2))
83 		return;
84 	if (dev->i2c_current_bus == bus)
85 		return;
86 
87 	switch (bus) {
88 	case 0:
89 		ngene_command_gpio_set(dev, 3, 0);
90 		ngene_command_gpio_set(dev, 2, 1);
91 		break;
92 
93 	case 1:
94 		ngene_command_gpio_set(dev, 2, 0);
95 		ngene_command_gpio_set(dev, 3, 1);
96 		break;
97 	}
98 	dev->i2c_current_bus = bus;
99 }
100 
101 static int ngene_i2c_master_xfer(struct i2c_adapter *adapter,
102 				 struct i2c_msg msg[], int num)
103 {
104 	struct ngene_channel *chan =
105 		(struct ngene_channel *)i2c_get_adapdata(adapter);
106 	struct ngene *dev = chan->dev;
107 
108 	mutex_lock(&dev->i2c_switch_mutex);
109 	ngene_i2c_set_bus(dev, chan->number);
110 
111 	if (num == 2 && msg[1].flags & I2C_M_RD && !(msg[0].flags & I2C_M_RD))
112 		if (!ngene_command_i2c_read(dev, msg[0].addr,
113 					    msg[0].buf, msg[0].len,
114 					    msg[1].buf, msg[1].len, 0))
115 			goto done;
116 
117 	if (num == 1 && !(msg[0].flags & I2C_M_RD))
118 		if (!ngene_command_i2c_write(dev, msg[0].addr,
119 					     msg[0].buf, msg[0].len))
120 			goto done;
121 	if (num == 1 && (msg[0].flags & I2C_M_RD))
122 		if (!ngene_command_i2c_read(dev, msg[0].addr, NULL, 0,
123 					    msg[0].buf, msg[0].len, 0))
124 			goto done;
125 
126 	mutex_unlock(&dev->i2c_switch_mutex);
127 	return -EIO;
128 
129 done:
130 	mutex_unlock(&dev->i2c_switch_mutex);
131 	return num;
132 }
133 
134 
135 static u32 ngene_i2c_functionality(struct i2c_adapter *adap)
136 {
137 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
138 }
139 
140 static const struct i2c_algorithm ngene_i2c_algo = {
141 	.master_xfer = ngene_i2c_master_xfer,
142 	.functionality = ngene_i2c_functionality,
143 };
144 
145 int ngene_i2c_init(struct ngene *dev, int dev_nr)
146 {
147 	struct i2c_adapter *adap = &(dev->channel[dev_nr].i2c_adapter);
148 
149 	i2c_set_adapdata(adap, &(dev->channel[dev_nr]));
150 
151 	strscpy(adap->name, "nGene", sizeof(adap->name));
152 
153 	adap->algo = &ngene_i2c_algo;
154 	adap->algo_data = (void *)&(dev->channel[dev_nr]);
155 	adap->dev.parent = &dev->pci_dev->dev;
156 
157 	return i2c_add_adapter(adap);
158 }
159 
160