1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Greybus Host Device 4 * 5 * Copyright 2014-2015 Google Inc. 6 * Copyright 2014-2015 Linaro Ltd. 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/slab.h> 11 #include <linux/greybus.h> 12 13 #include "greybus_trace.h" 14 15 EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_create); 16 EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_release); 17 EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_add); 18 EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_del); 19 EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_in); 20 EXPORT_TRACEPOINT_SYMBOL_GPL(gb_message_submit); 21 22 static struct ida gb_hd_bus_id_map; 23 24 int gb_hd_output(struct gb_host_device *hd, void *req, u16 size, u8 cmd, 25 bool async) 26 { 27 if (!hd || !hd->driver || !hd->driver->output) 28 return -EINVAL; 29 return hd->driver->output(hd, req, size, cmd, async); 30 } 31 EXPORT_SYMBOL_GPL(gb_hd_output); 32 33 static ssize_t bus_id_show(struct device *dev, 34 struct device_attribute *attr, char *buf) 35 { 36 struct gb_host_device *hd = to_gb_host_device(dev); 37 38 return sprintf(buf, "%d\n", hd->bus_id); 39 } 40 static DEVICE_ATTR_RO(bus_id); 41 42 static struct attribute *bus_attrs[] = { 43 &dev_attr_bus_id.attr, 44 NULL 45 }; 46 ATTRIBUTE_GROUPS(bus); 47 48 int gb_hd_cport_reserve(struct gb_host_device *hd, u16 cport_id) 49 { 50 struct ida *id_map = &hd->cport_id_map; 51 int ret; 52 53 ret = ida_simple_get(id_map, cport_id, cport_id + 1, GFP_KERNEL); 54 if (ret < 0) { 55 dev_err(&hd->dev, "failed to reserve cport %u\n", cport_id); 56 return ret; 57 } 58 59 return 0; 60 } 61 EXPORT_SYMBOL_GPL(gb_hd_cport_reserve); 62 63 void gb_hd_cport_release_reserved(struct gb_host_device *hd, u16 cport_id) 64 { 65 struct ida *id_map = &hd->cport_id_map; 66 67 ida_simple_remove(id_map, cport_id); 68 } 69 EXPORT_SYMBOL_GPL(gb_hd_cport_release_reserved); 70 71 /* Locking: Caller guarantees serialisation */ 72 int gb_hd_cport_allocate(struct gb_host_device *hd, int cport_id, 73 unsigned long flags) 74 { 75 struct ida *id_map = &hd->cport_id_map; 76 int ida_start, ida_end; 77 78 if (hd->driver->cport_allocate) 79 return hd->driver->cport_allocate(hd, cport_id, flags); 80 81 if (cport_id < 0) { 82 ida_start = 0; 83 ida_end = hd->num_cports; 84 } else if (cport_id < hd->num_cports) { 85 ida_start = cport_id; 86 ida_end = cport_id + 1; 87 } else { 88 dev_err(&hd->dev, "cport %d not available\n", cport_id); 89 return -EINVAL; 90 } 91 92 return ida_simple_get(id_map, ida_start, ida_end, GFP_KERNEL); 93 } 94 95 /* Locking: Caller guarantees serialisation */ 96 void gb_hd_cport_release(struct gb_host_device *hd, u16 cport_id) 97 { 98 if (hd->driver->cport_release) { 99 hd->driver->cport_release(hd, cport_id); 100 return; 101 } 102 103 ida_simple_remove(&hd->cport_id_map, cport_id); 104 } 105 106 static void gb_hd_release(struct device *dev) 107 { 108 struct gb_host_device *hd = to_gb_host_device(dev); 109 110 trace_gb_hd_release(hd); 111 112 if (hd->svc) 113 gb_svc_put(hd->svc); 114 ida_simple_remove(&gb_hd_bus_id_map, hd->bus_id); 115 ida_destroy(&hd->cport_id_map); 116 kfree(hd); 117 } 118 119 struct device_type greybus_hd_type = { 120 .name = "greybus_host_device", 121 .release = gb_hd_release, 122 }; 123 124 struct gb_host_device *gb_hd_create(struct gb_hd_driver *driver, 125 struct device *parent, 126 size_t buffer_size_max, 127 size_t num_cports) 128 { 129 struct gb_host_device *hd; 130 int ret; 131 132 /* 133 * Validate that the driver implements all of the callbacks 134 * so that we don't have to every time we make them. 135 */ 136 if ((!driver->message_send) || (!driver->message_cancel)) { 137 dev_err(parent, "mandatory hd-callbacks missing\n"); 138 return ERR_PTR(-EINVAL); 139 } 140 141 if (buffer_size_max < GB_OPERATION_MESSAGE_SIZE_MIN) { 142 dev_err(parent, "greybus host-device buffers too small\n"); 143 return ERR_PTR(-EINVAL); 144 } 145 146 if (num_cports == 0 || num_cports > CPORT_ID_MAX + 1) { 147 dev_err(parent, "Invalid number of CPorts: %zu\n", num_cports); 148 return ERR_PTR(-EINVAL); 149 } 150 151 /* 152 * Make sure to never allocate messages larger than what the Greybus 153 * protocol supports. 154 */ 155 if (buffer_size_max > GB_OPERATION_MESSAGE_SIZE_MAX) { 156 dev_warn(parent, "limiting buffer size to %u\n", 157 GB_OPERATION_MESSAGE_SIZE_MAX); 158 buffer_size_max = GB_OPERATION_MESSAGE_SIZE_MAX; 159 } 160 161 hd = kzalloc(sizeof(*hd) + driver->hd_priv_size, GFP_KERNEL); 162 if (!hd) 163 return ERR_PTR(-ENOMEM); 164 165 ret = ida_simple_get(&gb_hd_bus_id_map, 1, 0, GFP_KERNEL); 166 if (ret < 0) { 167 kfree(hd); 168 return ERR_PTR(ret); 169 } 170 hd->bus_id = ret; 171 172 hd->driver = driver; 173 INIT_LIST_HEAD(&hd->modules); 174 INIT_LIST_HEAD(&hd->connections); 175 ida_init(&hd->cport_id_map); 176 hd->buffer_size_max = buffer_size_max; 177 hd->num_cports = num_cports; 178 179 hd->dev.parent = parent; 180 hd->dev.bus = &greybus_bus_type; 181 hd->dev.type = &greybus_hd_type; 182 hd->dev.groups = bus_groups; 183 hd->dev.dma_mask = hd->dev.parent->dma_mask; 184 device_initialize(&hd->dev); 185 dev_set_name(&hd->dev, "greybus%d", hd->bus_id); 186 187 trace_gb_hd_create(hd); 188 189 hd->svc = gb_svc_create(hd); 190 if (!hd->svc) { 191 dev_err(&hd->dev, "failed to create svc\n"); 192 put_device(&hd->dev); 193 return ERR_PTR(-ENOMEM); 194 } 195 196 return hd; 197 } 198 EXPORT_SYMBOL_GPL(gb_hd_create); 199 200 int gb_hd_add(struct gb_host_device *hd) 201 { 202 int ret; 203 204 ret = device_add(&hd->dev); 205 if (ret) 206 return ret; 207 208 ret = gb_svc_add(hd->svc); 209 if (ret) { 210 device_del(&hd->dev); 211 return ret; 212 } 213 214 trace_gb_hd_add(hd); 215 216 return 0; 217 } 218 EXPORT_SYMBOL_GPL(gb_hd_add); 219 220 void gb_hd_del(struct gb_host_device *hd) 221 { 222 trace_gb_hd_del(hd); 223 224 /* 225 * Tear down the svc and flush any on-going hotplug processing before 226 * removing the remaining interfaces. 227 */ 228 gb_svc_del(hd->svc); 229 230 device_del(&hd->dev); 231 } 232 EXPORT_SYMBOL_GPL(gb_hd_del); 233 234 void gb_hd_shutdown(struct gb_host_device *hd) 235 { 236 gb_svc_del(hd->svc); 237 } 238 EXPORT_SYMBOL_GPL(gb_hd_shutdown); 239 240 void gb_hd_put(struct gb_host_device *hd) 241 { 242 put_device(&hd->dev); 243 } 244 EXPORT_SYMBOL_GPL(gb_hd_put); 245 246 int __init gb_hd_init(void) 247 { 248 ida_init(&gb_hd_bus_id_map); 249 250 return 0; 251 } 252 253 void gb_hd_exit(void) 254 { 255 ida_destroy(&gb_hd_bus_id_map); 256 } 257