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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 | // SPDX-License-Identifier: GPL-2.0 /* Copyright (C) IBM Corporation 2023 */ #include <linux/cdev.h> #include <linux/device.h> #include <linux/fs.h> #include <linux/fsi.h> #include <linux/module.h> #include <linux/mod_devicetable.h> #include "fsi-master-i2cr.h" #include "fsi-slave.h" struct i2cr_scom { struct device dev; struct cdev cdev; struct fsi_master_i2cr *i2cr; }; static loff_t i2cr_scom_llseek(struct file *file, loff_t offset, int whence) { switch (whence) { case SEEK_CUR: break; case SEEK_SET: file->f_pos = offset; break; default: return -EINVAL; } return offset; } static ssize_t i2cr_scom_read(struct file *filep, char __user *buf, size_t len, loff_t *offset) { struct i2cr_scom *scom = filep->private_data; u64 data; int ret; if (len != sizeof(data)) return -EINVAL; ret = fsi_master_i2cr_read(scom->i2cr, (u32)*offset, &data); if (ret) return ret; ret = copy_to_user(buf, &data, len); if (ret) return ret; return len; } static ssize_t i2cr_scom_write(struct file *filep, const char __user *buf, size_t len, loff_t *offset) { struct i2cr_scom *scom = filep->private_data; u64 data; int ret; if (len != sizeof(data)) return -EINVAL; ret = copy_from_user(&data, buf, len); if (ret) return ret; ret = fsi_master_i2cr_write(scom->i2cr, (u32)*offset, data); if (ret) return ret; return len; } static const struct file_operations i2cr_scom_fops = { .owner = THIS_MODULE, .open = simple_open, .llseek = i2cr_scom_llseek, .read = i2cr_scom_read, .write = i2cr_scom_write, }; static int i2cr_scom_probe(struct device *dev) { struct fsi_device *fsi_dev = to_fsi_dev(dev); struct i2cr_scom *scom; int didx; int ret; if (!is_fsi_master_i2cr(fsi_dev->slave->master)) return -ENODEV; scom = devm_kzalloc(dev, sizeof(*scom), GFP_KERNEL); if (!scom) return -ENOMEM; scom->i2cr = to_fsi_master_i2cr(fsi_dev->slave->master); dev_set_drvdata(dev, scom); scom->dev.type = &fsi_cdev_type; scom->dev.parent = dev; device_initialize(&scom->dev); ret = fsi_get_new_minor(fsi_dev, fsi_dev_scom, &scom->dev.devt, &didx); if (ret) return ret; dev_set_name(&scom->dev, "scom%d", didx); cdev_init(&scom->cdev, &i2cr_scom_fops); ret = cdev_device_add(&scom->cdev, &scom->dev); if (ret) fsi_free_minor(scom->dev.devt); return ret; } static int i2cr_scom_remove(struct device *dev) { struct i2cr_scom *scom = dev_get_drvdata(dev); cdev_device_del(&scom->cdev, &scom->dev); fsi_free_minor(scom->dev.devt); return 0; } static const struct of_device_id i2cr_scom_of_ids[] = { { .compatible = "ibm,i2cr-scom" }, { } }; MODULE_DEVICE_TABLE(of, i2cr_scom_of_ids); static const struct fsi_device_id i2cr_scom_ids[] = { { 0x5, FSI_VERSION_ANY }, { } }; static struct fsi_driver i2cr_scom_driver = { .id_table = i2cr_scom_ids, .drv = { .name = "i2cr_scom", .bus = &fsi_bus_type, .of_match_table = i2cr_scom_of_ids, .probe = i2cr_scom_probe, .remove = i2cr_scom_remove, } }; module_fsi_driver(i2cr_scom_driver); MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>"); MODULE_DESCRIPTION("IBM I2C Responder SCOM driver"); MODULE_LICENSE("GPL"); |