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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Driver for the NXP SAA7164 PCIe bridge4 *5 * Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com>6 */7 8#include <linux/module.h>9#include <linux/moduleparam.h>10#include <linux/init.h>11#include <linux/delay.h>12#include <linux/io.h>13 14#include "saa7164.h"15 16static int i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)17{18 struct saa7164_i2c *bus = i2c_adap->algo_data;19 struct saa7164_dev *dev = bus->dev;20 int i, retval = 0;21 22 dprintk(DBGLVL_I2C, "%s(num = %d)\n", __func__, num);23 24 for (i = 0 ; i < num; i++) {25 dprintk(DBGLVL_I2C, "%s(num = %d) addr = 0x%02x len = 0x%x\n",26 __func__, num, msgs[i].addr, msgs[i].len);27 if (msgs[i].flags & I2C_M_RD) {28 retval = saa7164_api_i2c_read(bus,29 msgs[i].addr,30 0 /* reglen */,31 NULL /* reg */, msgs[i].len, msgs[i].buf);32 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&33 msgs[i].addr == msgs[i + 1].addr) {34 /* write then read from same address */35 36 retval = saa7164_api_i2c_read(bus, msgs[i].addr,37 msgs[i].len, msgs[i].buf,38 msgs[i+1].len, msgs[i+1].buf39 );40 41 i++;42 43 if (retval < 0)44 goto err;45 } else {46 /* write */47 retval = saa7164_api_i2c_write(bus, msgs[i].addr,48 msgs[i].len, msgs[i].buf);49 }50 if (retval < 0)51 goto err;52 }53 return num;54 55err:56 return retval;57}58 59static u32 saa7164_functionality(struct i2c_adapter *adap)60{61 return I2C_FUNC_I2C;62}63 64static const struct i2c_algorithm saa7164_i2c_algo_template = {65 .master_xfer = i2c_xfer,66 .functionality = saa7164_functionality,67};68 69/* ----------------------------------------------------------------------- */70 71static const struct i2c_adapter saa7164_i2c_adap_template = {72 .name = "saa7164",73 .owner = THIS_MODULE,74 .algo = &saa7164_i2c_algo_template,75};76 77static const struct i2c_client saa7164_i2c_client_template = {78 .name = "saa7164 internal",79};80 81int saa7164_i2c_register(struct saa7164_i2c *bus)82{83 struct saa7164_dev *dev = bus->dev;84 85 dprintk(DBGLVL_I2C, "%s(bus = %d)\n", __func__, bus->nr);86 87 bus->i2c_adap = saa7164_i2c_adap_template;88 bus->i2c_client = saa7164_i2c_client_template;89 90 bus->i2c_adap.dev.parent = &dev->pci->dev;91 92 strscpy(bus->i2c_adap.name, bus->dev->name,93 sizeof(bus->i2c_adap.name));94 95 bus->i2c_adap.algo_data = bus;96 i2c_set_adapdata(&bus->i2c_adap, bus);97 i2c_add_adapter(&bus->i2c_adap);98 99 bus->i2c_client.adapter = &bus->i2c_adap;100 101 if (0 != bus->i2c_rc)102 printk(KERN_ERR "%s: i2c bus %d register FAILED\n",103 dev->name, bus->nr);104 105 return bus->i2c_rc;106}107 108int saa7164_i2c_unregister(struct saa7164_i2c *bus)109{110 i2c_del_adapter(&bus->i2c_adap);111 return 0;112}113