Re: [PATCH V6 1/4] rpmsg: core: Add signal API support

Deepak Kumar Singh
2021-05-06T17:18:54Z

Please ignore V6 patch set for rpmsg: core: Add signal API support.

Wrongly pushed.

On 5/6/2021 10:36 PM, Deepak Kumar Singh wrote:
> Some transports like Glink support the state notifications between
> clients using signals similar to serial protocol signals.
> Local glink client drivers can send and receive signals to glink
> clients running on remote processors.
>
> Add apis to support sending and receiving of signals by rpmsg clients.
>
> Signed-off-by: Chris Lew <clew@codeaurora.org>
> Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
> Signed-off-by: Arun Kumar Neelakantam <aneela@codeaurora.org>
> ---
> drivers/rpmsg/rpmsg_core.c | 40 ++++++++++++++++++++++++++++++++++++++++
> drivers/rpmsg/rpmsg_internal.h | 5 +++++
> include/linux/rpmsg.h | 27 +++++++++++++++++++++++++++
> 3 files changed, 72 insertions(+)
>
> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
> index 91de940..e6eb5a1 100644
> --- a/drivers/rpmsg/rpmsg_core.c
> +++ b/drivers/rpmsg/rpmsg_core.c
> @@ -283,6 +283,42 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
> }
> EXPORT_SYMBOL(rpmsg_trysend_offchannel);
>
> +/**
> + * rpmsg_get_signals() - get the signals for this endpoint
> + * @ept: the rpmsg endpoint
> + *
> + * Returns signal bits on success and an appropriate error value on failure.
> + */
> +int rpmsg_get_signals(struct rpmsg_endpoint *ept)
> +{
> + if (WARN_ON(!ept))
> + return -EINVAL;
> + if (!ept->ops->get_signals)
> + return -ENXIO;
> +
> + return ept->ops->get_signals(ept);
> +}
> +EXPORT_SYMBOL(rpmsg_get_signals);
> +
> +/**
> + * rpmsg_set_signals() - set the remote signals for this endpoint
> + * @ept: the rpmsg endpoint
> + * @set: set mask for signals
> + * @clear: clear mask for signals
> + *
> + * Returns 0 on success and an appropriate error value on failure.
> + */
> +int rpmsg_set_signals(struct rpmsg_endpoint *ept, u32 set, u32 clear)
> +{
> + if (WARN_ON(!ept))
> + return -EINVAL;
> + if (!ept->ops->set_signals)
> + return -ENXIO;
> +
> + return ept->ops->set_signals(ept, set, clear);
> +}
> +EXPORT_SYMBOL(rpmsg_set_signals);
> +
> /*
> * match a rpmsg channel with a channel info struct.
> * this is used to make sure we're not creating rpmsg devices for channels
> @@ -468,6 +504,10 @@ static int rpmsg_dev_probe(struct device *dev)
>
> rpdev->ept = ept;
> rpdev->src = ept->addr;
> +
> + if (rpdrv->signals)
> + ept->sig_cb = rpdrv->signals;
> +
> }
>
> err = rpdrv->probe(rpdev);
> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
> index 3fc83cd..8958d6c 100644
> --- a/drivers/rpmsg/rpmsg_internal.h
> +++ b/drivers/rpmsg/rpmsg_internal.h
> @@ -2,6 +2,7 @@
> /*
> * remote processor messaging bus internals
> *
> + * Copyright (c) 2018, The Linux Foundation.
> * Copyright (C) 2011 Texas Instruments, Inc.
> * Copyright (C) 2011 Google, Inc.
> *
> @@ -47,6 +48,8 @@ struct rpmsg_device_ops {
> * @trysendto: see @rpmsg_trysendto(), optional
> * @trysend_offchannel: see @rpmsg_trysend_offchannel(), optional
> * @poll: see @rpmsg_poll(), optional
> + * @get_signals: see @rpmsg_get_signals(), optional
> + * @set_signals: see @rpmsg_set_signals(), optional
> *
> * Indirection table for the operations that a rpmsg backend should implement.
> * In addition to @destroy_ept, the backend must at least implement @send and
> @@ -66,6 +69,8 @@ struct rpmsg_endpoint_ops {
> void *data, int len);
> __poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
> poll_table *wait);
> + int (*get_signals)(struct rpmsg_endpoint *ept);
> + int (*set_signals)(struct rpmsg_endpoint *ept, u32 set, u32 clear);
> };
>
> int rpmsg_register_device(struct rpmsg_device *rpdev);
> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
> index 9fe156d..c4dbb47 100644
> --- a/include/linux/rpmsg.h
> +++ b/include/linux/rpmsg.h
> @@ -2,6 +2,7 @@
> /*
> * Remote processor messaging
> *
> + * Copyright (c) 2018 The Linux Foundation.
> * Copyright (C) 2011 Texas Instruments, Inc.
> * Copyright (C) 2011 Google, Inc.
> * All rights reserved.
> @@ -60,6 +61,7 @@ struct rpmsg_device {
> };
>
> typedef int (*rpmsg_rx_cb_t)(struct rpmsg_device *, void *, int, void *, u32);
> +typedef int (*rpmsg_rx_sig_t)(struct rpmsg_device *, void *, u32, u32);
>
> /**
> * struct rpmsg_endpoint - binds a local rpmsg address to its user
> @@ -67,6 +69,7 @@ typedef int (*rpmsg_rx_cb_t)(struct rpmsg_device *, void *, int, void *, u32);
> * @refcount: when this drops to zero, the ept is deallocated
> * @cb: rx callback handler
> * @cb_lock: must be taken before accessing/changing @cb
> + * @sig_cb: rx serial signal handler
> * @addr: local rpmsg address
> * @priv: private data for the driver's use
> *
> @@ -89,6 +92,7 @@ struct rpmsg_endpoint {
> struct kref refcount;
> rpmsg_rx_cb_t cb;
> struct mutex cb_lock;
> + rpmsg_rx_sig_t sig_cb;
> u32 addr;
> void *priv;
>
> @@ -102,6 +106,7 @@ struct rpmsg_endpoint {
> * @probe: invoked when a matching rpmsg channel (i.e. device) is found
> * @remove: invoked when the rpmsg channel is removed
> * @callback: invoked when an inbound message is received on the channel
> + * @signals: invoked when a serial signal change is received on the channel
> */
> struct rpmsg_driver {
> struct device_driver drv;
> @@ -109,6 +114,8 @@ struct rpmsg_driver {
> int (*probe)(struct rpmsg_device *dev);
> void (*remove)(struct rpmsg_device *dev);
> int (*callback)(struct rpmsg_device *, void *, int, void *, u32);
> + int (*signals)(struct rpmsg_device *rpdev,
> + void *priv, u32 old, u32 new);
> };
>
> #if IS_ENABLED(CONFIG_RPMSG)
> @@ -135,6 +142,9 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
> __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
> poll_table *wait);
>
> +int rpmsg_get_signals(struct rpmsg_endpoint *ept);
> +int rpmsg_set_signals(struct rpmsg_endpoint *ept, u32 set, u32 clear);
> +
> #else
>
> static inline int register_rpmsg_device(struct rpmsg_device *dev)
> @@ -242,6 +252,23 @@ static inline __poll_t rpmsg_poll(struct rpmsg_endpoint *ept,
> return 0;
> }
>
> +static inline int rpmsg_get_signals(struct rpmsg_endpoint *ept)
> +{
> + /* This shouldn't be possible */
> + WARN_ON(1);
> +
> + return -ENXIO;
> +}
> +
> +static inline int rpmsg_set_signals(struct rpmsg_endpoint *ept,
> + u32 set, u32 clear)
> +{
> + /* This shouldn't be possible */
> + WARN_ON(1);
> +
> + return -ENXIO;
> +}
> +
> #endif /* IS_ENABLED(CONFIG_RPMSG) */
>
> /* use a macro to avoid include chaining to get THIS_MODULE */
>