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Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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#define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/kernel.h>#include <linux/module.h>#include <linux/rpmsg.h>#include <linux/of_device.h>#include <linux/pm_domain.h>#include <linux/slab.h>
#include "rpmsg_internal.h"
const struct class rpmsg_class = { .name = "rpmsg",};EXPORT_SYMBOL(rpmsg_class);
/** * rpmsg_create_channel() - create a new rpmsg channel * using its name and address info. * @rpdev: rpmsg device * @chinfo: channel_info to bind * * Return: a pointer to the new rpmsg device on success, or NULL on error. */struct rpmsg_device *rpmsg_create_channel(struct rpmsg_device *rpdev, struct rpmsg_channel_info *chinfo){ if (WARN_ON(!rpdev)) return NULL; if (!rpdev->ops || !rpdev->ops->create_channel) { dev_err(&rpdev->dev, "no create_channel ops found\n"); return NULL; }
return rpdev->ops->create_channel(rpdev, chinfo);}EXPORT_SYMBOL(rpmsg_create_channel);
/** * rpmsg_release_channel() - release a rpmsg channel * using its name and address info. * @rpdev: rpmsg device * @chinfo: channel_info to bind * * Return: 0 on success or an appropriate error value. */int rpmsg_release_channel(struct rpmsg_device *rpdev, struct rpmsg_channel_info *chinfo){ if (WARN_ON(!rpdev)) return -EINVAL; if (!rpdev->ops || !rpdev->ops->release_channel) { dev_err(&rpdev->dev, "no release_channel ops found\n"); return -ENXIO; }
return rpdev->ops->release_channel(rpdev, chinfo);}EXPORT_SYMBOL(rpmsg_release_channel);
/** * rpmsg_create_ept() - create a new rpmsg_endpoint * @rpdev: rpmsg channel device * @cb: rx callback handler * @priv: private data for the driver's use * @chinfo: channel_info with the local rpmsg address to bind with @cb * * Every rpmsg address in the system is bound to an rx callback (so when * inbound messages arrive, they are dispatched by the rpmsg bus using the * appropriate callback handler) by means of an rpmsg_endpoint struct. * * This function allows drivers to create such an endpoint, and by that, * bind a callback, and possibly some private data too, to an rpmsg address * (either one that is known in advance, or one that will be dynamically * assigned for them). * * Simple rpmsg drivers need not call rpmsg_create_ept, because an endpoint * is already created for them when they are probed by the rpmsg bus * (using the rx callback provided when they registered to the rpmsg bus). * * So things should just work for simple drivers: they already have an * endpoint, their rx callback is bound to their rpmsg address, and when * relevant inbound messages arrive (i.e. messages which their dst address * equals to the src address of their rpmsg channel), the driver's handler * is invoked to process it. * * That said, more complicated drivers might need to allocate * additional rpmsg addresses, and bind them to different rx callbacks. * To accomplish that, those drivers need to call this function. * * Drivers should provide their @rpdev channel (so the new endpoint would belong * to the same remote processor their channel belongs to), an rx callback * function, an optional private data (which is provided back when the * rx callback is invoked), and an address they want to bind with the * callback. If @addr is RPMSG_ADDR_ANY, then rpmsg_create_ept will * dynamically assign them an available rpmsg address (drivers should have * a very good reason why not to always use RPMSG_ADDR_ANY here). * * Return: a pointer to the endpoint on success, or NULL on error. */struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_device *rpdev, rpmsg_rx_cb_t cb, void *priv, struct rpmsg_channel_info chinfo){ if (WARN_ON(!rpdev)) return NULL;
return rpdev->ops->create_ept(rpdev, cb, priv, chinfo);}EXPORT_SYMBOL(rpmsg_create_ept);
/** * rpmsg_destroy_ept() - destroy an existing rpmsg endpoint * @ept: endpoing to destroy * * Should be used by drivers to destroy an rpmsg endpoint previously * created with rpmsg_create_ept(). As with other types of "free" NULL * is a valid parameter. */void rpmsg_destroy_ept(struct rpmsg_endpoint *ept){ if (ept && ept->ops) ept->ops->destroy_ept(ept);}EXPORT_SYMBOL(rpmsg_destroy_ept);
/** * rpmsg_send() - send a message across to the remote processor * @ept: the rpmsg endpoint * @data: payload of message * @len: length of payload * * This function sends @data of length @len on the @ept endpoint. * The message will be sent to the remote processor which the @ept * endpoint belongs to, using @ept's address and its associated rpmsg * device destination addresses. * In case there are no TX buffers available, the function will block until * one becomes available, or a timeout of 15 seconds elapses. When the latter * happens, -ERESTARTSYS is returned. * * Can only be called from process context (for now). * * Return: 0 on success and an appropriate error value on failure. */int rpmsg_send(struct rpmsg_endpoint *ept, const void *data, int len){ if (WARN_ON(!ept)) return -EINVAL; if (!ept->ops->send) return -ENXIO;
return ept->ops->send(ept, data, len);}EXPORT_SYMBOL(rpmsg_send);
/** * rpmsg_sendto() - send a message across to the remote processor, specify dst * @ept: the rpmsg endpoint * @data: payload of message * @len: length of payload * @dst: destination address * * This function sends @data of length @len to the remote @dst address. * The message will be sent to the remote processor which the @ept * endpoint belongs to, using @ept's address as source. * In case there are no TX buffers available, the function will block until * one becomes available, or a timeout of 15 seconds elapses. When the latter * happens, -ERESTARTSYS is returned. * * Can only be called from process context (for now). * * Return: 0 on success and an appropriate error value on failure. */int rpmsg_sendto(struct rpmsg_endpoint *ept, const void *data, int len, u32 dst){ if (WARN_ON(!ept)) return -EINVAL; if (!ept->ops->sendto) return -ENXIO;
return ept->ops->sendto(ept, data, len, dst);}EXPORT_SYMBOL(rpmsg_sendto);
/** * rpmsg_trysend() - send a message across to the remote processor * @ept: the rpmsg endpoint * @data: payload of message * @len: length of payload * * This function sends @data of length @len on the @ept endpoint. * The message will be sent to the remote processor which the @ept * endpoint belongs to, using @ept's address as source and its associated * rpdev's address as destination. * In case there are no TX buffers available, the function will immediately * return -ENOMEM without waiting until one becomes available. * * Can only be called from process context (for now). * * Return: 0 on success and an appropriate error value on failure. */int rpmsg_trysend(struct rpmsg_endpoint *ept, const void *data, int len){ if (WARN_ON(!ept)) return -EINVAL; if (!ept->ops->trysend) return -ENXIO;
return ept->ops->trysend(ept, data, len);}EXPORT_SYMBOL(rpmsg_trysend);
/** * rpmsg_trysendto() - send a message across to the remote processor, specify dst * @ept: the rpmsg endpoint * @data: payload of message * @len: length of payload * @dst: destination address * * This function sends @data of length @len to the remote @dst address. * The message will be sent to the remote processor which the @ept * endpoint belongs to, using @ept's address as source. * In case there are no TX buffers available, the function will immediately * return -ENOMEM without waiting until one becomes available. * * Can only be called from process context (for now). * * Return: 0 on success and an appropriate error value on failure. */int rpmsg_trysendto(struct rpmsg_endpoint *ept, const void *data, int len, u32 dst){ if (WARN_ON(!ept)) return -EINVAL; if (!ept->ops->trysendto) return -ENXIO;
return ept->ops->trysendto(ept, data, len, dst);}EXPORT_SYMBOL(rpmsg_trysendto);
/** * rpmsg_poll() - poll the endpoint's send buffers * @ept: the rpmsg endpoint * @filp: file for poll_wait() * @wait: poll_table for poll_wait() * * Return: mask representing the current state of the endpoint's send buffers */__poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp, poll_table *wait){ if (WARN_ON(!ept)) return 0; if (!ept->ops->poll) return 0;
return ept->ops->poll(ept, filp, wait);}EXPORT_SYMBOL(rpmsg_poll);
/** * rpmsg_set_flow_control() - request remote to pause/resume transmission * @ept: the rpmsg endpoint * @pause: pause transmission * @dst: destination address of the endpoint * * Return: 0 on success and an appropriate error value on failure. */int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool pause, u32 dst){ if (WARN_ON(!ept)) return -EINVAL; if (!ept->ops->set_flow_control) return -EOPNOTSUPP;
return ept->ops->set_flow_control(ept, pause, dst);}EXPORT_SYMBOL_GPL(rpmsg_set_flow_control);
/** * rpmsg_get_mtu() - get maximum transmission buffer size for sending message. * @ept: the rpmsg endpoint * * This function returns maximum buffer size available for a single outgoing message. * * Return: the maximum transmission size on success and an appropriate error * value on failure. */
ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept){ if (WARN_ON(!ept)) return -EINVAL; if (!ept->ops->get_mtu) return -ENOTSUPP;
return ept->ops->get_mtu(ept);}EXPORT_SYMBOL(rpmsg_get_mtu);
/* * match a rpmsg channel with a channel info struct. * this is used to make sure we're not creating rpmsg devices for channels * that already exist. */static int rpmsg_device_match(struct device *dev, const void *data){ const struct rpmsg_channel_info *chinfo = data; struct rpmsg_device *rpdev = to_rpmsg_device(dev);
if (chinfo->src != RPMSG_ADDR_ANY && chinfo->src != rpdev->src) return 0;
if (chinfo->dst != RPMSG_ADDR_ANY && chinfo->dst != rpdev->dst) return 0;
if (strncmp(chinfo->name, rpdev->id.name, RPMSG_NAME_SIZE)) return 0;
/* found a match ! */ return 1;}
struct device *rpmsg_find_device(struct device *parent, struct rpmsg_channel_info *chinfo){ return device_find_child(parent, chinfo, rpmsg_device_match);
}EXPORT_SYMBOL(rpmsg_find_device);
/* sysfs show configuration fields */#define rpmsg_show_attr(field, path, format_string) \static ssize_t \field##_show(struct device *dev, \ struct device_attribute *attr, char *buf) \{ \ struct rpmsg_device *rpdev = to_rpmsg_device(dev); \ \ return sprintf(buf, format_string, rpdev->path); \} \static DEVICE_ATTR_RO(field);
/* for more info, see Documentation/ABI/testing/sysfs-bus-rpmsg */rpmsg_show_attr(name, id.name, "%s\n");rpmsg_show_attr(src, src, "0x%x\n");rpmsg_show_attr(dst, dst, "0x%x\n");rpmsg_show_attr(announce, announce ? "true" : "false", "%s\n");
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf){ struct rpmsg_device *rpdev = to_rpmsg_device(dev); ssize_t len;
len = of_device_modalias(dev, buf, PAGE_SIZE); if (len != -ENODEV) return len;
return sprintf(buf, RPMSG_DEVICE_MODALIAS_FMT "\n", rpdev->id.name);}static DEVICE_ATTR_RO(modalias);
static struct attribute *rpmsg_dev_attrs[] = { &dev_attr_name.attr, &dev_attr_modalias.attr, &dev_attr_dst.attr, &dev_attr_src.attr, &dev_attr_announce.attr, NULL,};ATTRIBUTE_GROUPS(rpmsg_dev);
/* rpmsg devices and drivers are matched using the service name */static inline int rpmsg_id_match(const struct rpmsg_device *rpdev, const struct rpmsg_device_id *id){ return strncmp(id->name, rpdev->id.name, RPMSG_NAME_SIZE) == 0;}
/* match rpmsg channel and rpmsg driver */static int rpmsg_dev_match(struct device *dev, const struct device_driver *drv){ struct rpmsg_device *rpdev = to_rpmsg_device(dev); const struct rpmsg_driver *rpdrv = to_rpmsg_driver(drv); const struct rpmsg_device_id *ids = rpdrv->id_table; unsigned int i; int ret;
ret = device_match_driver_override(dev, drv); if (ret >= 0) return ret;
if (ids) for (i = 0; ids[i].name[0]; i++) if (rpmsg_id_match(rpdev, &ids[i])) { rpdev->id.driver_data = ids[i].driver_data; return 1; }
return of_driver_match_device(dev, drv);}
static int rpmsg_uevent(const struct device *dev, struct kobj_uevent_env *env){ const struct rpmsg_device *rpdev = to_rpmsg_device(dev); int ret;
ret = of_device_uevent_modalias(dev, env); if (ret != -ENODEV) return ret;
return add_uevent_var(env, "MODALIAS=" RPMSG_DEVICE_MODALIAS_FMT, rpdev->id.name);}
/* * when an rpmsg driver is probed with a channel, we seamlessly create * it an endpoint, binding its rx callback to a unique local rpmsg * address. * * if we need to, we also announce about this channel to the remote * processor (needed in case the driver is exposing an rpmsg service). */static int rpmsg_dev_probe(struct device *dev){ struct rpmsg_device *rpdev = to_rpmsg_device(dev); struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver); struct rpmsg_channel_info chinfo = {}; struct rpmsg_endpoint *ept = NULL; int err;
err = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON | PD_FLAG_DETACH_POWER_OFF); if (err) goto out;
if (rpdrv->callback) { strscpy(chinfo.name, rpdev->id.name, sizeof(chinfo.name)); chinfo.src = rpdev->src; chinfo.dst = RPMSG_ADDR_ANY;
ept = rpmsg_create_ept(rpdev, rpdrv->callback, NULL, chinfo); if (!ept) { dev_err(dev, "failed to create endpoint\n"); err = -ENOMEM; goto out; }
rpdev->ept = ept; rpdev->src = ept->addr;
ept->flow_cb = rpdrv->flowcontrol; }
err = rpdrv->probe(rpdev); if (err) { dev_err(dev, "%s: failed: %d\n", __func__, err); goto destroy_ept; }
if (ept && rpdev->ops->announce_create) { err = rpdev->ops->announce_create(rpdev); if (err) { dev_err(dev, "failed to announce creation\n"); goto remove_rpdev; } }
return 0;
remove_rpdev: if (rpdrv->remove) rpdrv->remove(rpdev);destroy_ept: if (ept) rpmsg_destroy_ept(ept);out: return err;}
static void rpmsg_dev_remove(struct device *dev){ struct rpmsg_device *rpdev = to_rpmsg_device(dev); struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver);
if (rpdev->ops->announce_destroy) rpdev->ops->announce_destroy(rpdev);
if (rpdrv->remove) rpdrv->remove(rpdev);
if (rpdev->ept) rpmsg_destroy_ept(rpdev->ept);}
static const struct bus_type rpmsg_bus = { .name = "rpmsg", .match = rpmsg_dev_match, .dev_groups = rpmsg_dev_groups, .driver_override = true, .uevent = rpmsg_uevent, .probe = rpmsg_dev_probe, .remove = rpmsg_dev_remove,};
/* * A helper for registering rpmsg device with driver override and name. * Drivers should not be using it, but instead rpmsg_register_device(). */int rpmsg_register_device_override(struct rpmsg_device *rpdev, const char *driver_override){ struct device *dev = &rpdev->dev; int ret;
if (driver_override) strscpy_pad(rpdev->id.name, driver_override, RPMSG_NAME_SIZE);
dev_set_name(dev, "%s.%s.%d.%d", dev_name(dev->parent), rpdev->id.name, rpdev->src, rpdev->dst);
dev->bus = &rpmsg_bus;
device_initialize(dev); if (driver_override) { ret = device_set_driver_override(dev, driver_override); if (ret) { dev_err(dev, "device_set_driver_override() failed: %d\n", ret); put_device(dev); return ret; } }
ret = device_add(dev); if (ret) { dev_err(dev, "device_add failed: %d\n", ret); put_device(dev); }
return ret;}EXPORT_SYMBOL(rpmsg_register_device_override);
int rpmsg_register_device(struct rpmsg_device *rpdev){ return rpmsg_register_device_override(rpdev, NULL);}EXPORT_SYMBOL(rpmsg_register_device);
/* * find an existing channel using its name + address properties, * and destroy it */int rpmsg_unregister_device(struct device *parent, struct rpmsg_channel_info *chinfo){ struct device *dev;
dev = rpmsg_find_device(parent, chinfo); if (!dev) return -EINVAL;
device_unregister(dev);
put_device(dev);
return 0;}EXPORT_SYMBOL(rpmsg_unregister_device);
/** * __register_rpmsg_driver() - register an rpmsg driver with the rpmsg bus * @rpdrv: pointer to a struct rpmsg_driver * @owner: owning module/driver * * Return: 0 on success, and an appropriate error value on failure. */int __register_rpmsg_driver(struct rpmsg_driver *rpdrv, struct module *owner){ rpdrv->drv.bus = &rpmsg_bus; rpdrv->drv.owner = owner; return driver_register(&rpdrv->drv);}EXPORT_SYMBOL(__register_rpmsg_driver);
/** * unregister_rpmsg_driver() - unregister an rpmsg driver from the rpmsg bus * @rpdrv: pointer to a struct rpmsg_driver * * Return: 0 on success, and an appropriate error value on failure. */void unregister_rpmsg_driver(struct rpmsg_driver *rpdrv){ driver_unregister(&rpdrv->drv);}EXPORT_SYMBOL(unregister_rpmsg_driver);
static int __init rpmsg_init(void){ int ret;
ret = class_register(&rpmsg_class); if (ret) { pr_err("failed to register rpmsg class\n"); return ret; }
ret = bus_register(&rpmsg_bus); if (ret) { pr_err("failed to register rpmsg bus: %d\n", ret); class_unregister(&rpmsg_class); } return ret;}postcore_initcall(rpmsg_init);
static void __exit rpmsg_fini(void){ bus_unregister(&rpmsg_bus); class_unregister(&rpmsg_class);}module_exit(rpmsg_fini);
MODULE_DESCRIPTION("remote processor messaging bus");MODULE_LICENSE("GPL v2");