1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Greybus Module code |
4 | * |
5 | * Copyright 2016 Google Inc. |
6 | * Copyright 2016 Linaro Ltd. |
7 | */ |
8 | |
9 | #include <linux/greybus.h> |
10 | #include "greybus_trace.h" |
11 | |
12 | static ssize_t eject_store(struct device *dev, |
13 | struct device_attribute *attr, |
14 | const char *buf, size_t len) |
15 | { |
16 | struct gb_module *module = to_gb_module(dev); |
17 | struct gb_interface *intf; |
18 | size_t i; |
19 | long val; |
20 | int ret; |
21 | |
22 | ret = kstrtol(s: buf, base: 0, res: &val); |
23 | if (ret) |
24 | return ret; |
25 | |
26 | if (!val) |
27 | return len; |
28 | |
29 | for (i = 0; i < module->num_interfaces; ++i) { |
30 | intf = module->interfaces[i]; |
31 | |
32 | mutex_lock(&intf->mutex); |
33 | /* Set flag to prevent concurrent activation. */ |
34 | intf->ejected = true; |
35 | gb_interface_disable(intf); |
36 | gb_interface_deactivate(intf); |
37 | mutex_unlock(lock: &intf->mutex); |
38 | } |
39 | |
40 | /* Tell the SVC to eject the primary interface. */ |
41 | ret = gb_svc_intf_eject(svc: module->hd->svc, intf_id: module->module_id); |
42 | if (ret) |
43 | return ret; |
44 | |
45 | return len; |
46 | } |
47 | static DEVICE_ATTR_WO(eject); |
48 | |
49 | static ssize_t module_id_show(struct device *dev, |
50 | struct device_attribute *attr, char *buf) |
51 | { |
52 | struct gb_module *module = to_gb_module(dev); |
53 | |
54 | return sprintf(buf, fmt: "%u\n" , module->module_id); |
55 | } |
56 | static DEVICE_ATTR_RO(module_id); |
57 | |
58 | static ssize_t num_interfaces_show(struct device *dev, |
59 | struct device_attribute *attr, char *buf) |
60 | { |
61 | struct gb_module *module = to_gb_module(dev); |
62 | |
63 | return sprintf(buf, fmt: "%zu\n" , module->num_interfaces); |
64 | } |
65 | static DEVICE_ATTR_RO(num_interfaces); |
66 | |
67 | static struct attribute *module_attrs[] = { |
68 | &dev_attr_eject.attr, |
69 | &dev_attr_module_id.attr, |
70 | &dev_attr_num_interfaces.attr, |
71 | NULL, |
72 | }; |
73 | ATTRIBUTE_GROUPS(module); |
74 | |
75 | static void gb_module_release(struct device *dev) |
76 | { |
77 | struct gb_module *module = to_gb_module(dev); |
78 | |
79 | trace_gb_module_release(module); |
80 | |
81 | kfree(objp: module); |
82 | } |
83 | |
84 | const struct device_type greybus_module_type = { |
85 | .name = "greybus_module" , |
86 | .release = gb_module_release, |
87 | }; |
88 | |
89 | struct gb_module *gb_module_create(struct gb_host_device *hd, u8 module_id, |
90 | size_t num_interfaces) |
91 | { |
92 | struct gb_interface *intf; |
93 | struct gb_module *module; |
94 | int i; |
95 | |
96 | module = kzalloc(struct_size(module, interfaces, num_interfaces), |
97 | GFP_KERNEL); |
98 | if (!module) |
99 | return NULL; |
100 | |
101 | module->hd = hd; |
102 | module->module_id = module_id; |
103 | module->num_interfaces = num_interfaces; |
104 | |
105 | module->dev.parent = &hd->dev; |
106 | module->dev.bus = &greybus_bus_type; |
107 | module->dev.type = &greybus_module_type; |
108 | module->dev.groups = module_groups; |
109 | module->dev.dma_mask = hd->dev.dma_mask; |
110 | device_initialize(dev: &module->dev); |
111 | dev_set_name(dev: &module->dev, name: "%d-%u" , hd->bus_id, module_id); |
112 | |
113 | trace_gb_module_create(module); |
114 | |
115 | for (i = 0; i < num_interfaces; ++i) { |
116 | intf = gb_interface_create(module, interface_id: module_id + i); |
117 | if (!intf) { |
118 | dev_err(&module->dev, "failed to create interface %u\n" , |
119 | module_id + i); |
120 | goto err_put_interfaces; |
121 | } |
122 | module->interfaces[i] = intf; |
123 | } |
124 | |
125 | return module; |
126 | |
127 | err_put_interfaces: |
128 | for (--i; i >= 0; --i) |
129 | gb_interface_put(intf: module->interfaces[i]); |
130 | |
131 | put_device(dev: &module->dev); |
132 | |
133 | return NULL; |
134 | } |
135 | |
136 | /* |
137 | * Register and enable an interface after first attempting to activate it. |
138 | */ |
139 | static void gb_module_register_interface(struct gb_interface *intf) |
140 | { |
141 | struct gb_module *module = intf->module; |
142 | u8 intf_id = intf->interface_id; |
143 | int ret; |
144 | |
145 | mutex_lock(&intf->mutex); |
146 | |
147 | ret = gb_interface_activate(intf); |
148 | if (ret) { |
149 | if (intf->type != GB_INTERFACE_TYPE_DUMMY) { |
150 | dev_err(&module->dev, |
151 | "failed to activate interface %u: %d\n" , |
152 | intf_id, ret); |
153 | } |
154 | |
155 | gb_interface_add(intf); |
156 | goto err_unlock; |
157 | } |
158 | |
159 | ret = gb_interface_add(intf); |
160 | if (ret) |
161 | goto err_interface_deactivate; |
162 | |
163 | ret = gb_interface_enable(intf); |
164 | if (ret) { |
165 | dev_err(&module->dev, "failed to enable interface %u: %d\n" , |
166 | intf_id, ret); |
167 | goto err_interface_deactivate; |
168 | } |
169 | |
170 | mutex_unlock(lock: &intf->mutex); |
171 | |
172 | return; |
173 | |
174 | err_interface_deactivate: |
175 | gb_interface_deactivate(intf); |
176 | err_unlock: |
177 | mutex_unlock(lock: &intf->mutex); |
178 | } |
179 | |
180 | static void gb_module_deregister_interface(struct gb_interface *intf) |
181 | { |
182 | /* Mark as disconnected to prevent I/O during disable. */ |
183 | if (intf->module->disconnected) |
184 | intf->disconnected = true; |
185 | |
186 | mutex_lock(&intf->mutex); |
187 | intf->removed = true; |
188 | gb_interface_disable(intf); |
189 | gb_interface_deactivate(intf); |
190 | mutex_unlock(lock: &intf->mutex); |
191 | |
192 | gb_interface_del(intf); |
193 | } |
194 | |
195 | /* Register a module and its interfaces. */ |
196 | int gb_module_add(struct gb_module *module) |
197 | { |
198 | size_t i; |
199 | int ret; |
200 | |
201 | ret = device_add(dev: &module->dev); |
202 | if (ret) { |
203 | dev_err(&module->dev, "failed to register module: %d\n" , ret); |
204 | return ret; |
205 | } |
206 | |
207 | trace_gb_module_add(module); |
208 | |
209 | for (i = 0; i < module->num_interfaces; ++i) |
210 | gb_module_register_interface(intf: module->interfaces[i]); |
211 | |
212 | return 0; |
213 | } |
214 | |
215 | /* Deregister a module and its interfaces. */ |
216 | void gb_module_del(struct gb_module *module) |
217 | { |
218 | size_t i; |
219 | |
220 | for (i = 0; i < module->num_interfaces; ++i) |
221 | gb_module_deregister_interface(intf: module->interfaces[i]); |
222 | |
223 | trace_gb_module_del(module); |
224 | |
225 | device_del(dev: &module->dev); |
226 | } |
227 | |
228 | void gb_module_put(struct gb_module *module) |
229 | { |
230 | size_t i; |
231 | |
232 | for (i = 0; i < module->num_interfaces; ++i) |
233 | gb_interface_put(intf: module->interfaces[i]); |
234 | |
235 | put_device(dev: &module->dev); |
236 | } |
237 | |