ngene-i2c.c

  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 */
 31static 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
 58static 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
 80static 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
101static 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
129done:
130	mutex_unlock(&dev->i2c_switch_mutex);
131	return num;
132}
133
134
135static u32 ngene_i2c_functionality(struct i2c_adapter *adap)
136{
137	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
138}
139
140static const struct i2c_algorithm ngene_i2c_algo = {
141	.master_xfer = ngene_i2c_master_xfer,
142	.functionality = ngene_i2c_functionality,
143};
144
145int 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