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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * common keywest i2c layer4 *5 * Copyright (c) by Takashi Iwai <tiwai@suse.de>6 */7 8 9#include <linux/init.h>10#include <linux/i2c.h>11#include <linux/delay.h>12#include <linux/module.h>13#include <sound/core.h>14#include "pmac.h"15 16static struct pmac_keywest *keywest_ctx;17static bool keywest_probed;18 19static int keywest_probe(struct i2c_client *client)20{21 keywest_probed = true;22 /* If instantiated via i2c-powermac, we still need to set the client */23 if (!keywest_ctx->client)24 keywest_ctx->client = client;25 i2c_set_clientdata(client, keywest_ctx);26 return 0;27}28 29/*30 * This is kind of a hack, best would be to turn powermac to fixed i2c31 * bus numbers and declare the sound device as part of platform32 * initialization33 */34static int keywest_attach_adapter(struct i2c_adapter *adapter)35{36 struct i2c_board_info info;37 struct i2c_client *client;38 39 if (! keywest_ctx)40 return -EINVAL;41 42 if (strncmp(adapter->name, "mac-io", 6))43 return -EINVAL; /* ignored */44 45 memset(&info, 0, sizeof(struct i2c_board_info));46 strscpy(info.type, "keywest", I2C_NAME_SIZE);47 info.addr = keywest_ctx->addr;48 client = i2c_new_client_device(adapter, &info);49 if (IS_ERR(client))50 return PTR_ERR(client);51 keywest_ctx->client = client;52 53 /*54 * We know the driver is already loaded, so the device should be55 * already bound. If not it means binding failed, and then there56 * is no point in keeping the device instantiated.57 */58 if (!keywest_ctx->client->dev.driver) {59 i2c_unregister_device(keywest_ctx->client);60 keywest_ctx->client = NULL;61 return -ENODEV;62 }63 64 /*65 * Let i2c-core delete that device on driver removal.66 * This is safe because i2c-core holds the core_lock mutex for us.67 */68 list_add_tail(&keywest_ctx->client->detected,69 &to_i2c_driver(keywest_ctx->client->dev.driver)->clients);70 return 0;71}72 73static void keywest_remove(struct i2c_client *client)74{75 if (! keywest_ctx)76 return;77 if (client == keywest_ctx->client)78 keywest_ctx->client = NULL;79}80 81 82static const struct i2c_device_id keywest_i2c_id[] = {83 { "MAC,tas3004" }, /* instantiated by i2c-powermac */84 { "keywest" }, /* instantiated by us if needed */85 { }86};87MODULE_DEVICE_TABLE(i2c, keywest_i2c_id);88 89static struct i2c_driver keywest_driver = {90 .driver = {91 .name = "PMac Keywest Audio",92 },93 .probe = keywest_probe,94 .remove = keywest_remove,95 .id_table = keywest_i2c_id,96};97 98/* exported */99void snd_pmac_keywest_cleanup(struct pmac_keywest *i2c)100{101 if (keywest_ctx && keywest_ctx == i2c) {102 i2c_del_driver(&keywest_driver);103 keywest_ctx = NULL;104 }105}106 107int snd_pmac_tumbler_post_init(void)108{109 int err;110 111 if (!keywest_ctx || !keywest_ctx->client)112 return -ENXIO;113 114 err = keywest_ctx->init_client(keywest_ctx);115 if (err < 0) {116 dev_err(&keywest_ctx->client->dev,117 "tumbler: %i :cannot initialize the MCS\n", err);118 return err;119 }120 return 0;121}122 123/* exported */124int snd_pmac_keywest_init(struct pmac_keywest *i2c)125{126 struct i2c_adapter *adap;127 int err, i = 0;128 129 if (keywest_ctx)130 return -EBUSY;131 132 adap = i2c_get_adapter(0);133 if (!adap)134 return -EPROBE_DEFER;135 136 keywest_ctx = i2c;137 138 err = i2c_add_driver(&keywest_driver);139 if (err) {140 dev_err(&i2c->client->dev, "cannot register keywest i2c driver\n");141 i2c_put_adapter(adap);142 return err;143 }144 145 /* There was already a device from i2c-powermac. Great, let's return */146 if (keywest_probed)147 return 0;148 149 /* We assume Macs have consecutive I2C bus numbers starting at 0 */150 while (adap) {151 /* Scan for devices to be bound to */152 err = keywest_attach_adapter(adap);153 if (!err)154 return 0;155 i2c_put_adapter(adap);156 adap = i2c_get_adapter(++i);157 }158 159 return -ENODEV;160}161