Message ID | 20210712123752.10449-3-arnaud.pouliquen@foss.st.com (mailing list archive) |
---|---|
State | Changes Requested |
Headers | show |
Series | Restructure the rpmsg char to decorrelate the control part. | expand |
On Mon 12 Jul 05:37 PDT 2021, Arnaud Pouliquen wrote: [..] > diff --git a/drivers/rpmsg/rpmsg_char.h b/drivers/rpmsg/rpmsg_char.h > new file mode 100644 > index 000000000000..22573b60e008 > --- /dev/null > +++ b/drivers/rpmsg/rpmsg_char.h > @@ -0,0 +1,49 @@ > +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ > +/* > + * Copyright (C) STMicroelectronics 2021. > + */ > + > +#ifndef __RPMSG_CHRDEV_H__ > +#define __RPMSG_CHRDEV_H__ > + > +#if IS_REACHABLE(CONFIG_RPMSG_CHAR) This does allow you to build a kernel with RPMSG_CHAR=m and RPMSG_CTRL=y without link failures. Any modules in the system will be able to call rpmsg_chrdev_eptdev_create(), but the rpmsg_ctrl driver will only end up in the stub. This sounds like a recipe for a terrible debugging session... Regards, Bjorn > +/** > + * rpmsg_chrdev_eptdev_create() - register char device based on an endpoint > + * @rpdev: prepared rpdev to be used for creating endpoints > + * @parent: parent device > + * @chinfo: associated endpoint channel information. > + * > + * This function create a new rpmsg char endpoint device to instantiate a new > + * endpoint based on chinfo information. > + */ > +int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, > + struct rpmsg_channel_info chinfo); > + > +/** > + * rpmsg_chrdev_eptdev_destroy() - destroy created char device endpoint. > + * @data: private data associated to the endpoint device > + * > + * This function destroys a rpmsg char endpoint device created by the RPMSG_DESTROY_EPT_IOCTL > + * control. > + */ > +int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data); > + > +#else /*IS_REACHABLE(CONFIG_RPMSG_CHAR) */ > + > +static inline int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, > + struct rpmsg_channel_info chinfo) > +{ > + return -EINVAL; > +} > + > +static inline int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data) > +{ > + /* This shouldn't be possible */ > + WARN_ON(1); > + > + return 0; > +} > + > +#endif /*IS_REACHABLE(CONFIG_RPMSG_CHAR) */ > + > +#endif /*__RPMSG_CHRDEV_H__ */ > -- > 2.17.1 >
On 10/9/21 1:29 AM, Bjorn Andersson wrote: > On Mon 12 Jul 05:37 PDT 2021, Arnaud Pouliquen wrote: > [..] >> diff --git a/drivers/rpmsg/rpmsg_char.h b/drivers/rpmsg/rpmsg_char.h >> new file mode 100644 >> index 000000000000..22573b60e008 >> --- /dev/null >> +++ b/drivers/rpmsg/rpmsg_char.h >> @@ -0,0 +1,49 @@ >> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ >> +/* >> + * Copyright (C) STMicroelectronics 2021. >> + */ >> + >> +#ifndef __RPMSG_CHRDEV_H__ >> +#define __RPMSG_CHRDEV_H__ >> + >> +#if IS_REACHABLE(CONFIG_RPMSG_CHAR) > > This does allow you to build a kernel with RPMSG_CHAR=m and RPMSG_CTRL=y > without link failures. Any modules in the system will be able to call > rpmsg_chrdev_eptdev_create(), but the rpmsg_ctrl driver will only end up > in the stub. > > This sounds like a recipe for a terrible debugging session... The RPMSG_CREATE_EPT_IOCTL control create a dependency between the rpmsg_ctrl and the rpmsg_char. The build error option seems not a good alternative. And in case of RPMSG_CHAR=m and RPMSG_CTRL=y, an error is returned so not only a stub. What about adding a WARN_ON(1) in rpmsg_chrdev_eptdev_create with an associated comment to ease the debug? Regards, Arnaud > > Regards, > Bjorn > >> +/** >> + * rpmsg_chrdev_eptdev_create() - register char device based on an endpoint >> + * @rpdev: prepared rpdev to be used for creating endpoints >> + * @parent: parent device >> + * @chinfo: associated endpoint channel information. >> + * >> + * This function create a new rpmsg char endpoint device to instantiate a new >> + * endpoint based on chinfo information. >> + */ >> +int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, >> + struct rpmsg_channel_info chinfo); >> + >> +/** >> + * rpmsg_chrdev_eptdev_destroy() - destroy created char device endpoint. >> + * @data: private data associated to the endpoint device >> + * >> + * This function destroys a rpmsg char endpoint device created by the RPMSG_DESTROY_EPT_IOCTL >> + * control. >> + */ >> +int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data); >> + >> +#else /*IS_REACHABLE(CONFIG_RPMSG_CHAR) */ >> + >> +static inline int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, >> + struct rpmsg_channel_info chinfo) >> +{ >> + return -EINVAL; >> +} >> + >> +static inline int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data) >> +{ >> + /* This shouldn't be possible */ >> + WARN_ON(1); >> + >> + return 0; >> +} >> + >> +#endif /*IS_REACHABLE(CONFIG_RPMSG_CHAR) */ >> + >> +#endif /*__RPMSG_CHRDEV_H__ */ >> -- >> 2.17.1 >>
diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c index b5907b80727c..941c5c54dd72 100644 --- a/drivers/rpmsg/rpmsg_char.c +++ b/drivers/rpmsg/rpmsg_char.c @@ -1,5 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* + * Copyright (C) 2021, STMicroelectronics * Copyright (c) 2016, Linaro Ltd. * Copyright (c) 2012, Michal Simek <monstr@monstr.eu> * Copyright (c) 2012, PetaLogix @@ -22,6 +23,8 @@ #include <linux/uaccess.h> #include <uapi/linux/rpmsg.h> +#include "rpmsg_char.h" + #define RPMSG_DEV_MAX (MINORMASK + 1) static dev_t rpmsg_major; @@ -76,7 +79,7 @@ struct rpmsg_eptdev { wait_queue_head_t readq; }; -static int rpmsg_eptdev_destroy(struct device *dev, void *data) +int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data) { struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev); @@ -95,6 +98,7 @@ static int rpmsg_eptdev_destroy(struct device *dev, void *data) return 0; } +EXPORT_SYMBOL(rpmsg_chrdev_eptdev_destroy); static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len, void *priv, u32 addr) @@ -278,7 +282,7 @@ static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd, if (cmd != RPMSG_DESTROY_EPT_IOCTL) return -EINVAL; - return rpmsg_eptdev_destroy(&eptdev->dev, NULL); + return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL); } static const struct file_operations rpmsg_eptdev_fops = { @@ -337,10 +341,9 @@ static void rpmsg_eptdev_release_device(struct device *dev) kfree(eptdev); } -static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev, +int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, struct rpmsg_channel_info chinfo) { - struct rpmsg_device *rpdev = ctrldev->rpdev; struct rpmsg_eptdev *eptdev; struct device *dev; int ret; @@ -360,7 +363,7 @@ static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev, device_initialize(dev); dev->class = rpmsg_class; - dev->parent = &ctrldev->dev; + dev->parent = parent; dev->groups = rpmsg_eptdev_groups; dev_set_drvdata(dev, eptdev); @@ -403,6 +406,7 @@ static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev, return ret; } +EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create); static int rpmsg_ctrldev_open(struct inode *inode, struct file *filp) { @@ -442,7 +446,7 @@ static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd, chinfo.src = eptinfo.src; chinfo.dst = eptinfo.dst; - return rpmsg_eptdev_create(ctrldev, chinfo); + return rpmsg_chrdev_eptdev_create(ctrldev->rpdev, &ctrldev->dev, chinfo); }; static const struct file_operations rpmsg_ctrldev_fops = { @@ -528,7 +532,7 @@ static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev) int ret; /* Destroy all endpoints */ - ret = device_for_each_child(&ctrldev->dev, NULL, rpmsg_eptdev_destroy); + ret = device_for_each_child(&ctrldev->dev, NULL, rpmsg_chrdev_eptdev_destroy); if (ret) dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret); diff --git a/drivers/rpmsg/rpmsg_char.h b/drivers/rpmsg/rpmsg_char.h new file mode 100644 index 000000000000..22573b60e008 --- /dev/null +++ b/drivers/rpmsg/rpmsg_char.h @@ -0,0 +1,49 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +/* + * Copyright (C) STMicroelectronics 2021. + */ + +#ifndef __RPMSG_CHRDEV_H__ +#define __RPMSG_CHRDEV_H__ + +#if IS_REACHABLE(CONFIG_RPMSG_CHAR) +/** + * rpmsg_chrdev_eptdev_create() - register char device based on an endpoint + * @rpdev: prepared rpdev to be used for creating endpoints + * @parent: parent device + * @chinfo: associated endpoint channel information. + * + * This function create a new rpmsg char endpoint device to instantiate a new + * endpoint based on chinfo information. + */ +int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, + struct rpmsg_channel_info chinfo); + +/** + * rpmsg_chrdev_eptdev_destroy() - destroy created char device endpoint. + * @data: private data associated to the endpoint device + * + * This function destroys a rpmsg char endpoint device created by the RPMSG_DESTROY_EPT_IOCTL + * control. + */ +int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data); + +#else /*IS_REACHABLE(CONFIG_RPMSG_CHAR) */ + +static inline int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent, + struct rpmsg_channel_info chinfo) +{ + return -EINVAL; +} + +static inline int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data) +{ + /* This shouldn't be possible */ + WARN_ON(1); + + return 0; +} + +#endif /*IS_REACHABLE(CONFIG_RPMSG_CHAR) */ + +#endif /*__RPMSG_CHRDEV_H__ */