1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Driver for the NXP SAA7164 PCIe bridge 4 * 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 16 static 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].buf 39 ); 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 55 err: 56 return retval; 57 } 58 59 static u32 saa7164_functionality(struct i2c_adapter *adap) 60 { 61 return I2C_FUNC_I2C; 62 } 63 64 static const struct i2c_algorithm saa7164_i2c_algo_template = { 65 .master_xfer = i2c_xfer, 66 .functionality = saa7164_functionality, 67 }; 68 69 /* ----------------------------------------------------------------------- */ 70 71 static const struct i2c_adapter saa7164_i2c_adap_template = { 72 .name = "saa7164", 73 .owner = THIS_MODULE, 74 .algo = &saa7164_i2c_algo_template, 75 }; 76 77 static const struct i2c_client saa7164_i2c_client_template = { 78 .name = "saa7164 internal", 79 }; 80 81 int 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 } 107 108 int saa7164_i2c_unregister(struct saa7164_i2c *bus) 109 { 110 i2c_del_adapter(&bus->i2c_adap); 111 return 0; 112 } 113