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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 | // SPDX-License-Identifier: GPL-2.0-or-later /* Copyright (c) 2021 IBM Corp. */ #include <linux/delay.h> #include <linux/device.h> #include <linux/errno.h> #include <linux/list.h> #include <linux/module.h> #include <linux/sched/signal.h> #include <linux/serio.h> #include <linux/slab.h> #include "kcs_bmc_client.h" struct kcs_bmc_serio { struct list_head entry; struct kcs_bmc_client client; struct serio *port; spinlock_t lock; }; static inline struct kcs_bmc_serio *client_to_kcs_bmc_serio(struct kcs_bmc_client *client) { return container_of(client, struct kcs_bmc_serio, client); } static irqreturn_t kcs_bmc_serio_event(struct kcs_bmc_client *client) { struct kcs_bmc_serio *priv; u8 handled = IRQ_NONE; u8 status; priv = client_to_kcs_bmc_serio(client); spin_lock(&priv->lock); status = kcs_bmc_read_status(client->dev); if (status & KCS_BMC_STR_IBF) handled = serio_interrupt(priv->port, kcs_bmc_read_data(client->dev), 0); spin_unlock(&priv->lock); return handled; } static const struct kcs_bmc_client_ops kcs_bmc_serio_client_ops = { .event = kcs_bmc_serio_event, }; static int kcs_bmc_serio_open(struct serio *port) { struct kcs_bmc_serio *priv = port->port_data; return kcs_bmc_enable_device(priv->client.dev, &priv->client); } static void kcs_bmc_serio_close(struct serio *port) { struct kcs_bmc_serio *priv = port->port_data; kcs_bmc_disable_device(priv->client.dev, &priv->client); } static DEFINE_SPINLOCK(kcs_bmc_serio_instances_lock); static LIST_HEAD(kcs_bmc_serio_instances); static int kcs_bmc_serio_add_device(struct kcs_bmc_device *kcs_bmc) { struct kcs_bmc_serio *priv; struct serio *port; priv = devm_kzalloc(kcs_bmc->dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; /* Use kzalloc() as the allocation is cleaned up with kfree() via serio_unregister_port() */ port = kzalloc(sizeof(*port), GFP_KERNEL); if (!port) return -ENOMEM; port->id.type = SERIO_8042; port->open = kcs_bmc_serio_open; port->close = kcs_bmc_serio_close; port->port_data = priv; port->dev.parent = kcs_bmc->dev; spin_lock_init(&priv->lock); priv->port = port; priv->client.dev = kcs_bmc; priv->client.ops = &kcs_bmc_serio_client_ops; spin_lock_irq(&kcs_bmc_serio_instances_lock); list_add(&priv->entry, &kcs_bmc_serio_instances); spin_unlock_irq(&kcs_bmc_serio_instances_lock); serio_register_port(port); dev_info(kcs_bmc->dev, "Initialised serio client for channel %d", kcs_bmc->channel); return 0; } static int kcs_bmc_serio_remove_device(struct kcs_bmc_device *kcs_bmc) { struct kcs_bmc_serio *priv = NULL, *pos; spin_lock_irq(&kcs_bmc_serio_instances_lock); list_for_each_entry(pos, &kcs_bmc_serio_instances, entry) { if (pos->client.dev == kcs_bmc) { priv = pos; list_del(&pos->entry); break; } } spin_unlock_irq(&kcs_bmc_serio_instances_lock); if (!priv) return -ENODEV; /* kfree()s priv->port via put_device() */ serio_unregister_port(priv->port); /* Ensure the IBF IRQ is disabled if we were the active client */ kcs_bmc_disable_device(kcs_bmc, &priv->client); devm_kfree(priv->client.dev->dev, priv); return 0; } static const struct kcs_bmc_driver_ops kcs_bmc_serio_driver_ops = { .add_device = kcs_bmc_serio_add_device, .remove_device = kcs_bmc_serio_remove_device, }; static struct kcs_bmc_driver kcs_bmc_serio_driver = { .ops = &kcs_bmc_serio_driver_ops, }; static int __init kcs_bmc_serio_init(void) { kcs_bmc_register_driver(&kcs_bmc_serio_driver); return 0; } module_init(kcs_bmc_serio_init); static void __exit kcs_bmc_serio_exit(void) { kcs_bmc_unregister_driver(&kcs_bmc_serio_driver); } module_exit(kcs_bmc_serio_exit); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>"); MODULE_DESCRIPTION("Adapter driver for serio access to BMC KCS devices"); |