1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (c) 2015-2018, Intel Corporation.
4 * Copyright (c) 2021, IBM Corp.
5 */
6
7 #include <linux/device.h>
8 #include <linux/list.h>
9 #include <linux/module.h>
10 #include <linux/mutex.h>
11
12 #include "kcs_bmc.h"
13
14 /* Implement both the device and client interfaces here */
15 #include "kcs_bmc_device.h"
16 #include "kcs_bmc_client.h"
17
18 /* Record registered devices and drivers */
19 static DEFINE_MUTEX(kcs_bmc_lock);
20 static LIST_HEAD(kcs_bmc_devices);
21 static LIST_HEAD(kcs_bmc_drivers);
22
23 /* Consumer data access */
24
kcs_bmc_read_data(struct kcs_bmc_device * kcs_bmc)25 u8 kcs_bmc_read_data(struct kcs_bmc_device *kcs_bmc)
26 {
27 return kcs_bmc->ops->io_inputb(kcs_bmc, kcs_bmc->ioreg.idr);
28 }
29 EXPORT_SYMBOL(kcs_bmc_read_data);
30
kcs_bmc_write_data(struct kcs_bmc_device * kcs_bmc,u8 data)31 void kcs_bmc_write_data(struct kcs_bmc_device *kcs_bmc, u8 data)
32 {
33 kcs_bmc->ops->io_outputb(kcs_bmc, kcs_bmc->ioreg.odr, data);
34 }
35 EXPORT_SYMBOL(kcs_bmc_write_data);
36
kcs_bmc_read_status(struct kcs_bmc_device * kcs_bmc)37 u8 kcs_bmc_read_status(struct kcs_bmc_device *kcs_bmc)
38 {
39 return kcs_bmc->ops->io_inputb(kcs_bmc, kcs_bmc->ioreg.str);
40 }
41 EXPORT_SYMBOL(kcs_bmc_read_status);
42
kcs_bmc_write_status(struct kcs_bmc_device * kcs_bmc,u8 data)43 void kcs_bmc_write_status(struct kcs_bmc_device *kcs_bmc, u8 data)
44 {
45 kcs_bmc->ops->io_outputb(kcs_bmc, kcs_bmc->ioreg.str, data);
46 }
47 EXPORT_SYMBOL(kcs_bmc_write_status);
48
kcs_bmc_update_status(struct kcs_bmc_device * kcs_bmc,u8 mask,u8 val)49 void kcs_bmc_update_status(struct kcs_bmc_device *kcs_bmc, u8 mask, u8 val)
50 {
51 kcs_bmc->ops->io_updateb(kcs_bmc, kcs_bmc->ioreg.str, mask, val);
52 }
53 EXPORT_SYMBOL(kcs_bmc_update_status);
54
kcs_bmc_handle_event(struct kcs_bmc_device * kcs_bmc)55 irqreturn_t kcs_bmc_handle_event(struct kcs_bmc_device *kcs_bmc)
56 {
57 struct kcs_bmc_client *client;
58 irqreturn_t rc = IRQ_NONE;
59
60 spin_lock(&kcs_bmc->lock);
61 client = kcs_bmc->client;
62 if (client)
63 rc = client->ops->event(client);
64 spin_unlock(&kcs_bmc->lock);
65
66 return rc;
67 }
68 EXPORT_SYMBOL(kcs_bmc_handle_event);
69
kcs_bmc_enable_device(struct kcs_bmc_device * kcs_bmc,struct kcs_bmc_client * client)70 int kcs_bmc_enable_device(struct kcs_bmc_device *kcs_bmc, struct kcs_bmc_client *client)
71 {
72 int rc;
73
74 spin_lock_irq(&kcs_bmc->lock);
75 if (kcs_bmc->client) {
76 rc = -EBUSY;
77 } else {
78 u8 mask = KCS_BMC_EVENT_TYPE_IBF;
79
80 kcs_bmc->client = client;
81 kcs_bmc_update_event_mask(kcs_bmc, mask, mask);
82 rc = 0;
83 }
84 spin_unlock_irq(&kcs_bmc->lock);
85
86 return rc;
87 }
88 EXPORT_SYMBOL(kcs_bmc_enable_device);
89
kcs_bmc_disable_device(struct kcs_bmc_device * kcs_bmc,struct kcs_bmc_client * client)90 void kcs_bmc_disable_device(struct kcs_bmc_device *kcs_bmc, struct kcs_bmc_client *client)
91 {
92 spin_lock_irq(&kcs_bmc->lock);
93 if (client == kcs_bmc->client) {
94 u8 mask = KCS_BMC_EVENT_TYPE_IBF | KCS_BMC_EVENT_TYPE_OBE;
95
96 kcs_bmc_update_event_mask(kcs_bmc, mask, 0);
97 kcs_bmc->client = NULL;
98 }
99 spin_unlock_irq(&kcs_bmc->lock);
100 }
101 EXPORT_SYMBOL(kcs_bmc_disable_device);
102
kcs_bmc_add_device(struct kcs_bmc_device * kcs_bmc)103 int kcs_bmc_add_device(struct kcs_bmc_device *kcs_bmc)
104 {
105 struct kcs_bmc_driver *drv;
106 int error = 0;
107 int rc;
108
109 spin_lock_init(&kcs_bmc->lock);
110 kcs_bmc->client = NULL;
111
112 mutex_lock(&kcs_bmc_lock);
113 list_add(&kcs_bmc->entry, &kcs_bmc_devices);
114 list_for_each_entry(drv, &kcs_bmc_drivers, entry) {
115 rc = drv->ops->add_device(kcs_bmc);
116 if (!rc)
117 continue;
118
119 dev_err(kcs_bmc->dev, "Failed to add chardev for KCS channel %d: %d",
120 kcs_bmc->channel, rc);
121 error = rc;
122 }
123 mutex_unlock(&kcs_bmc_lock);
124
125 return error;
126 }
127 EXPORT_SYMBOL(kcs_bmc_add_device);
128
kcs_bmc_remove_device(struct kcs_bmc_device * kcs_bmc)129 void kcs_bmc_remove_device(struct kcs_bmc_device *kcs_bmc)
130 {
131 struct kcs_bmc_driver *drv;
132 int rc;
133
134 mutex_lock(&kcs_bmc_lock);
135 list_del(&kcs_bmc->entry);
136 list_for_each_entry(drv, &kcs_bmc_drivers, entry) {
137 rc = drv->ops->remove_device(kcs_bmc);
138 if (rc)
139 dev_err(kcs_bmc->dev, "Failed to remove chardev for KCS channel %d: %d",
140 kcs_bmc->channel, rc);
141 }
142 mutex_unlock(&kcs_bmc_lock);
143 }
144 EXPORT_SYMBOL(kcs_bmc_remove_device);
145
kcs_bmc_register_driver(struct kcs_bmc_driver * drv)146 void kcs_bmc_register_driver(struct kcs_bmc_driver *drv)
147 {
148 struct kcs_bmc_device *kcs_bmc;
149 int rc;
150
151 mutex_lock(&kcs_bmc_lock);
152 list_add(&drv->entry, &kcs_bmc_drivers);
153 list_for_each_entry(kcs_bmc, &kcs_bmc_devices, entry) {
154 rc = drv->ops->add_device(kcs_bmc);
155 if (rc)
156 dev_err(kcs_bmc->dev, "Failed to add driver for KCS channel %d: %d",
157 kcs_bmc->channel, rc);
158 }
159 mutex_unlock(&kcs_bmc_lock);
160 }
161 EXPORT_SYMBOL(kcs_bmc_register_driver);
162
kcs_bmc_unregister_driver(struct kcs_bmc_driver * drv)163 void kcs_bmc_unregister_driver(struct kcs_bmc_driver *drv)
164 {
165 struct kcs_bmc_device *kcs_bmc;
166 int rc;
167
168 mutex_lock(&kcs_bmc_lock);
169 list_del(&drv->entry);
170 list_for_each_entry(kcs_bmc, &kcs_bmc_devices, entry) {
171 rc = drv->ops->remove_device(kcs_bmc);
172 if (rc)
173 dev_err(kcs_bmc->dev, "Failed to remove driver for KCS channel %d: %d",
174 kcs_bmc->channel, rc);
175 }
176 mutex_unlock(&kcs_bmc_lock);
177 }
178 EXPORT_SYMBOL(kcs_bmc_unregister_driver);
179
kcs_bmc_update_event_mask(struct kcs_bmc_device * kcs_bmc,u8 mask,u8 events)180 void kcs_bmc_update_event_mask(struct kcs_bmc_device *kcs_bmc, u8 mask, u8 events)
181 {
182 kcs_bmc->ops->irq_mask_update(kcs_bmc, mask, events);
183 }
184 EXPORT_SYMBOL(kcs_bmc_update_event_mask);
185
186 MODULE_LICENSE("GPL v2");
187 MODULE_AUTHOR("Haiyue Wang <haiyue.wang@linux.intel.com>");
188 MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");
189 MODULE_DESCRIPTION("KCS BMC to handle the IPMI request from system software");
190