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1// SPDX-License-Identifier: GPL-2.02/*3 * Greybus Host Device4 *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 15EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_create);16EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_release);17EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_add);18EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_del);19EXPORT_TRACEPOINT_SYMBOL_GPL(gb_hd_in);20EXPORT_TRACEPOINT_SYMBOL_GPL(gb_message_submit);21 22static struct ida gb_hd_bus_id_map;23 24int 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}31EXPORT_SYMBOL_GPL(gb_hd_output);32 33static 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}40static DEVICE_ATTR_RO(bus_id);41 42static struct attribute *bus_attrs[] = {43 &dev_attr_bus_id.attr,44 NULL45};46ATTRIBUTE_GROUPS(bus);47 48int 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_alloc_range(id_map, cport_id, cport_id, 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}61EXPORT_SYMBOL_GPL(gb_hd_cport_reserve);62 63void 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_free(id_map, cport_id);68}69EXPORT_SYMBOL_GPL(gb_hd_cport_release_reserved);70 71/* Locking: Caller guarantees serialisation */72int 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 - 1;84 } else if (cport_id < hd->num_cports) {85 ida_start = cport_id;86 ida_end = cport_id;87 } else {88 dev_err(&hd->dev, "cport %d not available\n", cport_id);89 return -EINVAL;90 }91 92 return ida_alloc_range(id_map, ida_start, ida_end, GFP_KERNEL);93}94 95/* Locking: Caller guarantees serialisation */96void 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_free(&hd->cport_id_map, cport_id);104}105 106static 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_free(&gb_hd_bus_id_map, hd->bus_id);115 ida_destroy(&hd->cport_id_map);116 kfree(hd);117}118 119const struct device_type greybus_hd_type = {120 .name = "greybus_host_device",121 .release = gb_hd_release,122};123 124struct 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 callbacks134 * 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 Greybus153 * 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_alloc_min(&gb_hd_bus_id_map, 1, 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}198EXPORT_SYMBOL_GPL(gb_hd_create);199 200int 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}218EXPORT_SYMBOL_GPL(gb_hd_add);219 220void 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 before226 * removing the remaining interfaces.227 */228 gb_svc_del(hd->svc);229 230 device_del(&hd->dev);231}232EXPORT_SYMBOL_GPL(gb_hd_del);233 234void gb_hd_shutdown(struct gb_host_device *hd)235{236 gb_svc_del(hd->svc);237}238EXPORT_SYMBOL_GPL(gb_hd_shutdown);239 240void gb_hd_put(struct gb_host_device *hd)241{242 put_device(&hd->dev);243}244EXPORT_SYMBOL_GPL(gb_hd_put);245 246int __init gb_hd_init(void)247{248 ida_init(&gb_hd_bus_id_map);249 250 return 0;251}252 253void gb_hd_exit(void)254{255 ida_destroy(&gb_hd_bus_id_map);256}257