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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright 1998-2009 VIA Technologies, Inc. All Rights Reserved.4 * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.5 6 */7 8#include <linux/platform_device.h>9#include <linux/delay.h>10#include <linux/spinlock.h>11#include <linux/module.h>12#include <linux/via-core.h>13#include <linux/via_i2c.h>14 15/*16 * There can only be one set of these, so there's no point in having17 * them be dynamically allocated...18 */19#define VIAFB_NUM_I2C 520static struct via_i2c_stuff via_i2c_par[VIAFB_NUM_I2C];21static struct viafb_dev *i2c_vdev; /* Passed in from core */22 23static void via_i2c_setscl(void *data, int state)24{25 u8 val;26 struct via_port_cfg *adap_data = data;27 unsigned long flags;28 29 spin_lock_irqsave(&i2c_vdev->reg_lock, flags);30 val = via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0xF0;31 if (state)32 val |= 0x20;33 else34 val &= ~0x20;35 switch (adap_data->type) {36 case VIA_PORT_I2C:37 val |= 0x01;38 break;39 case VIA_PORT_GPIO:40 val |= 0x82;41 break;42 default:43 printk(KERN_ERR "viafb_i2c: specify wrong i2c type.\n");44 }45 via_write_reg(adap_data->io_port, adap_data->ioport_index, val);46 spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);47}48 49static int via_i2c_getscl(void *data)50{51 struct via_port_cfg *adap_data = data;52 unsigned long flags;53 int ret = 0;54 55 spin_lock_irqsave(&i2c_vdev->reg_lock, flags);56 if (adap_data->type == VIA_PORT_GPIO)57 via_write_reg_mask(adap_data->io_port, adap_data->ioport_index,58 0, 0x80);59 if (via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0x08)60 ret = 1;61 spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);62 return ret;63}64 65static int via_i2c_getsda(void *data)66{67 struct via_port_cfg *adap_data = data;68 unsigned long flags;69 int ret = 0;70 71 spin_lock_irqsave(&i2c_vdev->reg_lock, flags);72 if (adap_data->type == VIA_PORT_GPIO)73 via_write_reg_mask(adap_data->io_port, adap_data->ioport_index,74 0, 0x40);75 if (via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0x04)76 ret = 1;77 spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);78 return ret;79}80 81static void via_i2c_setsda(void *data, int state)82{83 u8 val;84 struct via_port_cfg *adap_data = data;85 unsigned long flags;86 87 spin_lock_irqsave(&i2c_vdev->reg_lock, flags);88 val = via_read_reg(adap_data->io_port, adap_data->ioport_index) & 0xF0;89 if (state)90 val |= 0x10;91 else92 val &= ~0x10;93 switch (adap_data->type) {94 case VIA_PORT_I2C:95 val |= 0x01;96 break;97 case VIA_PORT_GPIO:98 val |= 0x42;99 break;100 default:101 printk(KERN_ERR "viafb_i2c: specify wrong i2c type.\n");102 }103 via_write_reg(adap_data->io_port, adap_data->ioport_index, val);104 spin_unlock_irqrestore(&i2c_vdev->reg_lock, flags);105}106 107int viafb_i2c_readbyte(u8 adap, u8 target_addr, u8 index, u8 *pdata)108{109 int ret;110 u8 mm1[] = {0x00};111 struct i2c_msg msgs[2];112 113 if (!via_i2c_par[adap].is_active)114 return -ENODEV;115 *pdata = 0;116 msgs[0].flags = 0;117 msgs[1].flags = I2C_M_RD;118 msgs[0].addr = msgs[1].addr = target_addr / 2;119 mm1[0] = index;120 msgs[0].len = 1; msgs[1].len = 1;121 msgs[0].buf = mm1; msgs[1].buf = pdata;122 ret = i2c_transfer(&via_i2c_par[adap].adapter, msgs, 2);123 if (ret == 2)124 ret = 0;125 else if (ret >= 0)126 ret = -EIO;127 128 return ret;129}130 131int viafb_i2c_writebyte(u8 adap, u8 target_addr, u8 index, u8 data)132{133 int ret;134 u8 msg[2] = { index, data };135 struct i2c_msg msgs;136 137 if (!via_i2c_par[adap].is_active)138 return -ENODEV;139 msgs.flags = 0;140 msgs.addr = target_addr / 2;141 msgs.len = 2;142 msgs.buf = msg;143 ret = i2c_transfer(&via_i2c_par[adap].adapter, &msgs, 1);144 if (ret == 1)145 ret = 0;146 else if (ret >= 0)147 ret = -EIO;148 149 return ret;150}151 152int viafb_i2c_readbytes(u8 adap, u8 target_addr, u8 index, u8 *buff, int buff_len)153{154 int ret;155 u8 mm1[] = {0x00};156 struct i2c_msg msgs[2];157 158 if (!via_i2c_par[adap].is_active)159 return -ENODEV;160 msgs[0].flags = 0;161 msgs[1].flags = I2C_M_RD;162 msgs[0].addr = msgs[1].addr = target_addr / 2;163 mm1[0] = index;164 msgs[0].len = 1; msgs[1].len = buff_len;165 msgs[0].buf = mm1; msgs[1].buf = buff;166 ret = i2c_transfer(&via_i2c_par[adap].adapter, msgs, 2);167 if (ret == 2)168 ret = 0;169 else if (ret >= 0)170 ret = -EIO;171 172 return ret;173}174 175/*176 * Allow other viafb subdevices to look up a specific adapter177 * by port name.178 */179struct i2c_adapter *viafb_find_i2c_adapter(enum viafb_i2c_adap which)180{181 struct via_i2c_stuff *stuff = &via_i2c_par[which];182 183 return &stuff->adapter;184}185EXPORT_SYMBOL_GPL(viafb_find_i2c_adapter);186 187 188static int create_i2c_bus(struct i2c_adapter *adapter,189 struct i2c_algo_bit_data *algo,190 struct via_port_cfg *adap_cfg,191 struct pci_dev *pdev)192{193 algo->setsda = via_i2c_setsda;194 algo->setscl = via_i2c_setscl;195 algo->getsda = via_i2c_getsda;196 algo->getscl = via_i2c_getscl;197 algo->udelay = 10;198 algo->timeout = 2;199 algo->data = adap_cfg;200 201 sprintf(adapter->name, "viafb i2c io_port idx 0x%02x",202 adap_cfg->ioport_index);203 adapter->owner = THIS_MODULE;204 adapter->algo_data = algo;205 if (pdev)206 adapter->dev.parent = &pdev->dev;207 else208 adapter->dev.parent = NULL;209 /* i2c_set_adapdata(adapter, adap_cfg); */210 211 /* Raise SCL and SDA */212 via_i2c_setsda(adap_cfg, 1);213 via_i2c_setscl(adap_cfg, 1);214 udelay(20);215 216 return i2c_bit_add_bus(adapter);217}218 219static int viafb_i2c_probe(struct platform_device *platdev)220{221 int i, ret;222 struct via_port_cfg *configs;223 224 i2c_vdev = platdev->dev.platform_data;225 configs = i2c_vdev->port_cfg;226 227 for (i = 0; i < VIAFB_NUM_PORTS; i++) {228 struct via_port_cfg *adap_cfg = configs++;229 struct via_i2c_stuff *i2c_stuff = &via_i2c_par[i];230 231 i2c_stuff->is_active = 0;232 if (adap_cfg->type == 0 || adap_cfg->mode != VIA_MODE_I2C)233 continue;234 ret = create_i2c_bus(&i2c_stuff->adapter,235 &i2c_stuff->algo, adap_cfg,236 NULL); /* FIXME: PCIDEV */237 if (ret < 0) {238 printk(KERN_ERR "viafb: cannot create i2c bus %u:%d\n",239 i, ret);240 continue; /* Still try to make the rest */241 }242 i2c_stuff->is_active = 1;243 }244 245 return 0;246}247 248static void viafb_i2c_remove(struct platform_device *platdev)249{250 int i;251 252 for (i = 0; i < VIAFB_NUM_PORTS; i++) {253 struct via_i2c_stuff *i2c_stuff = &via_i2c_par[i];254 /*255 * Only remove those entries in the array that we've256 * actually used (and thus initialized algo_data)257 */258 if (i2c_stuff->is_active)259 i2c_del_adapter(&i2c_stuff->adapter);260 }261}262 263static struct platform_driver via_i2c_driver = {264 .driver = {265 .name = "viafb-i2c",266 },267 .probe = viafb_i2c_probe,268 .remove = viafb_i2c_remove,269};270 271int viafb_i2c_init(void)272{273 return platform_driver_register(&via_i2c_driver);274}275 276void viafb_i2c_exit(void)277{278 platform_driver_unregister(&via_i2c_driver);279}280