Commit | Line | Data |
---|---|---|
3a3d2f6a AJ |
1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* Copyright (c) 2021 IBM Corp. */ | |
3 | ||
4 | #include <linux/delay.h> | |
5 | #include <linux/device.h> | |
6 | #include <linux/errno.h> | |
7 | #include <linux/list.h> | |
8 | #include <linux/module.h> | |
9 | #include <linux/sched/signal.h> | |
10 | #include <linux/serio.h> | |
11 | #include <linux/slab.h> | |
12 | ||
13 | #include "kcs_bmc_client.h" | |
14 | ||
15 | struct kcs_bmc_serio { | |
16 | struct list_head entry; | |
17 | ||
18 | struct kcs_bmc_client client; | |
19 | struct serio *port; | |
20 | ||
21 | spinlock_t lock; | |
22 | }; | |
23 | ||
24 | static inline struct kcs_bmc_serio *client_to_kcs_bmc_serio(struct kcs_bmc_client *client) | |
25 | { | |
26 | return container_of(client, struct kcs_bmc_serio, client); | |
27 | } | |
28 | ||
29 | static irqreturn_t kcs_bmc_serio_event(struct kcs_bmc_client *client) | |
30 | { | |
31 | struct kcs_bmc_serio *priv; | |
32 | u8 handled = IRQ_NONE; | |
33 | u8 status; | |
34 | ||
35 | priv = client_to_kcs_bmc_serio(client); | |
36 | ||
37 | spin_lock(&priv->lock); | |
38 | ||
39 | status = kcs_bmc_read_status(client->dev); | |
40 | ||
41 | if (status & KCS_BMC_STR_IBF) | |
42 | handled = serio_interrupt(priv->port, kcs_bmc_read_data(client->dev), 0); | |
43 | ||
44 | spin_unlock(&priv->lock); | |
45 | ||
46 | return handled; | |
47 | } | |
48 | ||
49 | static const struct kcs_bmc_client_ops kcs_bmc_serio_client_ops = { | |
50 | .event = kcs_bmc_serio_event, | |
51 | }; | |
52 | ||
53 | static int kcs_bmc_serio_open(struct serio *port) | |
54 | { | |
55 | struct kcs_bmc_serio *priv = port->port_data; | |
56 | ||
57 | return kcs_bmc_enable_device(priv->client.dev, &priv->client); | |
58 | } | |
59 | ||
60 | static void kcs_bmc_serio_close(struct serio *port) | |
61 | { | |
62 | struct kcs_bmc_serio *priv = port->port_data; | |
63 | ||
64 | kcs_bmc_disable_device(priv->client.dev, &priv->client); | |
65 | } | |
66 | ||
67 | static DEFINE_SPINLOCK(kcs_bmc_serio_instances_lock); | |
68 | static LIST_HEAD(kcs_bmc_serio_instances); | |
69 | ||
70 | static int kcs_bmc_serio_add_device(struct kcs_bmc_device *kcs_bmc) | |
71 | { | |
72 | struct kcs_bmc_serio *priv; | |
73 | struct serio *port; | |
74 | ||
75 | priv = devm_kzalloc(kcs_bmc->dev, sizeof(*priv), GFP_KERNEL); | |
f281d010 CJ |
76 | if (!priv) |
77 | return -ENOMEM; | |
3a3d2f6a AJ |
78 | |
79 | /* Use kzalloc() as the allocation is cleaned up with kfree() via serio_unregister_port() */ | |
80 | port = kzalloc(sizeof(*port), GFP_KERNEL); | |
f281d010 | 81 | if (!port) |
3a3d2f6a AJ |
82 | return -ENOMEM; |
83 | ||
84 | port->id.type = SERIO_8042; | |
85 | port->open = kcs_bmc_serio_open; | |
86 | port->close = kcs_bmc_serio_close; | |
87 | port->port_data = priv; | |
88 | port->dev.parent = kcs_bmc->dev; | |
89 | ||
90 | spin_lock_init(&priv->lock); | |
91 | priv->port = port; | |
92 | priv->client.dev = kcs_bmc; | |
93 | priv->client.ops = &kcs_bmc_serio_client_ops; | |
94 | ||
95 | spin_lock_irq(&kcs_bmc_serio_instances_lock); | |
96 | list_add(&priv->entry, &kcs_bmc_serio_instances); | |
97 | spin_unlock_irq(&kcs_bmc_serio_instances_lock); | |
98 | ||
99 | serio_register_port(port); | |
100 | ||
101 | dev_info(kcs_bmc->dev, "Initialised serio client for channel %d", kcs_bmc->channel); | |
102 | ||
103 | return 0; | |
104 | } | |
105 | ||
106 | static int kcs_bmc_serio_remove_device(struct kcs_bmc_device *kcs_bmc) | |
107 | { | |
108 | struct kcs_bmc_serio *priv = NULL, *pos; | |
109 | ||
110 | spin_lock_irq(&kcs_bmc_serio_instances_lock); | |
111 | list_for_each_entry(pos, &kcs_bmc_serio_instances, entry) { | |
112 | if (pos->client.dev == kcs_bmc) { | |
113 | priv = pos; | |
114 | list_del(&pos->entry); | |
115 | break; | |
116 | } | |
117 | } | |
118 | spin_unlock_irq(&kcs_bmc_serio_instances_lock); | |
119 | ||
120 | if (!priv) | |
121 | return -ENODEV; | |
122 | ||
123 | /* kfree()s priv->port via put_device() */ | |
124 | serio_unregister_port(priv->port); | |
125 | ||
126 | /* Ensure the IBF IRQ is disabled if we were the active client */ | |
127 | kcs_bmc_disable_device(kcs_bmc, &priv->client); | |
128 | ||
129 | devm_kfree(priv->client.dev->dev, priv); | |
130 | ||
131 | return 0; | |
132 | } | |
133 | ||
134 | static const struct kcs_bmc_driver_ops kcs_bmc_serio_driver_ops = { | |
135 | .add_device = kcs_bmc_serio_add_device, | |
136 | .remove_device = kcs_bmc_serio_remove_device, | |
137 | }; | |
138 | ||
139 | static struct kcs_bmc_driver kcs_bmc_serio_driver = { | |
140 | .ops = &kcs_bmc_serio_driver_ops, | |
141 | }; | |
142 | ||
ec7174f6 | 143 | static int __init kcs_bmc_serio_init(void) |
3a3d2f6a AJ |
144 | { |
145 | kcs_bmc_register_driver(&kcs_bmc_serio_driver); | |
146 | ||
147 | return 0; | |
148 | } | |
149 | module_init(kcs_bmc_serio_init); | |
150 | ||
ec7174f6 | 151 | static void __exit kcs_bmc_serio_exit(void) |
3a3d2f6a AJ |
152 | { |
153 | kcs_bmc_unregister_driver(&kcs_bmc_serio_driver); | |
154 | } | |
155 | module_exit(kcs_bmc_serio_exit); | |
156 | ||
157 | MODULE_LICENSE("GPL v2"); | |
158 | MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>"); | |
159 | MODULE_DESCRIPTION("Adapter driver for serio access to BMC KCS devices"); |