| Message ID | 20211108141937.13016-11-arnaud.pouliquen@foss.st.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Restructure the rpmsg_char driver and introduce rpmsg_ctrl driver | expand |
On Mon 08 Nov 08:19 CST 2021, Arnaud Pouliquen wrote: > Allows to probe the endpoint device on a remote name service announcement, > by registering a rpmsg_driverfor the "rpmsg-raw" channel. > > With this patch the /dev/rpmsgX interface can be instantiated by the remote > firmware. > > Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com> > --- > drivers/rpmsg/rpmsg_char.c | 64 ++++++++++++++++++++++++++++++++++++++ > drivers/rpmsg/rpmsg_ctrl.c | 7 +++-- > 2 files changed, 69 insertions(+), 2 deletions(-) > > diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c > index 6a01e8e1c111..dd754c870ba1 100644 > --- a/drivers/rpmsg/rpmsg_char.c > +++ b/drivers/rpmsg/rpmsg_char.c > @@ -432,6 +432,58 @@ int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent > } > EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create); > > +static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev) > +{ > + struct rpmsg_channel_info chinfo; > + struct rpmsg_eptdev *eptdev; > + struct device *dev = &rpdev->dev; > + > + memcpy(chinfo.name, rpdev->id.name, RPMSG_NAME_SIZE); > + chinfo.src = rpdev->src; > + chinfo.dst = rpdev->dst; > + > + eptdev = rpmsg_chrdev_eptdev_alloc(rpdev, dev); > + if (IS_ERR(eptdev)) > + return PTR_ERR(eptdev); > + > + /* > + * Create the default endpoint associated to the rpmsg device and provide rpmsg_eptdev > + * structure as callback private data. > + * Do not allow the creation and release of an endpoint on /dev/rpmsgX open and close, > + * reuse the default endpoint instead > + */ > + eptdev->default_ept = rpmsg_create_default_ept(rpdev, rpmsg_ept_cb, eptdev, chinfo); > + if (!eptdev->default_ept) { > + dev_err(&rpdev->dev, "failed to create %s\n", chinfo.name); > + put_device(dev); Which get_device() does this correlate to? > + kfree(eptdev); After the device_initialize() in rpmsg_chrdev_eptdev_alloc() you're supposed to put_device() &eptdev->dev, which would kfree(eptdev)... Note though that rpmsg_eptdev_release_device() calls cdev_del(), which you can't do. It was however recently reported that this cdev_del() should be done in conjunction with the device_del() as the current implementation enables a race between release and fops->open. Regards, Bjorn > + return -EINVAL; > + } > + > + return rpmsg_chrdev_eptdev_add(eptdev, chinfo); > +} > + > +static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev) > +{ > + int ret; > + > + ret = device_for_each_child(&rpdev->dev, NULL, rpmsg_chrdev_eptdev_destroy); > + if (ret) > + dev_warn(&rpdev->dev, "failed to destroy endpoints: %d\n", ret); > +} > + > +static struct rpmsg_device_id rpmsg_chrdev_id_table[] = { > + { .name = "rpmsg-raw" }, > + { }, > +}; > + > +static struct rpmsg_driver rpmsg_chrdev_driver = { > + .probe = rpmsg_chrdev_probe, > + .remove = rpmsg_chrdev_remove, > + .id_table = rpmsg_chrdev_id_table, > + .drv.name = "rpmsg_chrdev", > +}; > + > static int rpmsg_chrdev_init(void) > { > int ret; > @@ -442,12 +494,24 @@ static int rpmsg_chrdev_init(void) > return ret; > } > > + ret = register_rpmsg_driver(&rpmsg_chrdev_driver); > + if (ret < 0) { > + pr_err("rpmsg: failed to register rpmsg raw driver\n"); > + goto free_region; > + } > + > return 0; > + > +free_region: > + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); > + > + return ret; > } > postcore_initcall(rpmsg_chrdev_init); > > static void rpmsg_chrdev_exit(void) > { > + unregister_rpmsg_driver(&rpmsg_chrdev_driver); > unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); > } > module_exit(rpmsg_chrdev_exit); > diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c > index 59d2bd264fdb..298e75dc7774 100644 > --- a/drivers/rpmsg/rpmsg_ctrl.c > +++ b/drivers/rpmsg/rpmsg_ctrl.c > @@ -10,6 +10,9 @@ > * Based on rpmsg performance statistics driver by Michal Simek, which in turn > * was based on TI & Google OMX rpmsg driver. > */ > + > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > + > #include <linux/cdev.h> > #include <linux/device.h> > #include <linux/fs.h> > @@ -193,13 +196,13 @@ static int rpmsg_ctrldev_init(void) > > ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg_ctrl"); > if (ret < 0) { > - pr_err("rpmsg: failed to allocate char dev region\n"); > + pr_err("failed to allocate char dev region\n"); > return ret; > } > > ret = register_rpmsg_driver(&rpmsg_ctrldev_driver); > if (ret < 0) { > - pr_err("rpmsg ctrl: failed to register rpmsg driver\n"); > + pr_err("failed to register rpmsg driver\n"); > unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); > } > > -- > 2.17.1 >
On 12/3/21 2:52 AM, Bjorn Andersson wrote: > On Mon 08 Nov 08:19 CST 2021, Arnaud Pouliquen wrote: > >> Allows to probe the endpoint device on a remote name service announcement, >> by registering a rpmsg_driverfor the "rpmsg-raw" channel. >> >> With this patch the /dev/rpmsgX interface can be instantiated by the remote >> firmware. >> >> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com> >> --- >> drivers/rpmsg/rpmsg_char.c | 64 ++++++++++++++++++++++++++++++++++++++ >> drivers/rpmsg/rpmsg_ctrl.c | 7 +++-- >> 2 files changed, 69 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c >> index 6a01e8e1c111..dd754c870ba1 100644 >> --- a/drivers/rpmsg/rpmsg_char.c >> +++ b/drivers/rpmsg/rpmsg_char.c >> @@ -432,6 +432,58 @@ int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent >> } >> EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create); >> >> +static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev) >> +{ >> + struct rpmsg_channel_info chinfo; >> + struct rpmsg_eptdev *eptdev; >> + struct device *dev = &rpdev->dev; >> + >> + memcpy(chinfo.name, rpdev->id.name, RPMSG_NAME_SIZE); >> + chinfo.src = rpdev->src; >> + chinfo.dst = rpdev->dst; >> + >> + eptdev = rpmsg_chrdev_eptdev_alloc(rpdev, dev); >> + if (IS_ERR(eptdev)) >> + return PTR_ERR(eptdev); >> + >> + /* >> + * Create the default endpoint associated to the rpmsg device and provide rpmsg_eptdev >> + * structure as callback private data. >> + * Do not allow the creation and release of an endpoint on /dev/rpmsgX open and close, >> + * reuse the default endpoint instead >> + */ >> + eptdev->default_ept = rpmsg_create_default_ept(rpdev, rpmsg_ept_cb, eptdev, chinfo); >> + if (!eptdev->default_ept) { >> + dev_err(&rpdev->dev, "failed to create %s\n", chinfo.name); >> + put_device(dev); > > Which get_device() does this correlate to? this is related to device_initialize [1]( and herited from the legacy implementation of rpmsg_char) [1] https://elixir.bootlin.com/linux/v5.16-rc3/source/drivers/base/core.c#L2860 > >> + kfree(eptdev); > > After the device_initialize() in rpmsg_chrdev_eptdev_alloc() you're > supposed to put_device() &eptdev->dev, which would kfree(eptdev)... dev->release is set only in rpmsg_chrdev_eptdev_add. and calling rpmsg_chrdev_eptdev_add at this level would need to handle the free of some uninitialized parameters. That why I directly free it here. > > > Note though that rpmsg_eptdev_release_device() calls cdev_del(), which > you can't do. It was however recently reported that this cdev_del() > should be done in conjunction with the device_del() as the current > implementation enables a race between release and fops->open. I'm not sure to understand your point here. Is it related to your previous comment concerning the use of put_device or do you expect something from me specific in the around device_del and cdev_del? Thanks, Arnaud > > Regards, > Bjorn > >> + return -EINVAL; >> + } >> + >> + return rpmsg_chrdev_eptdev_add(eptdev, chinfo); >> +} >> + >> +static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev) >> +{ >> + int ret; >> + >> + ret = device_for_each_child(&rpdev->dev, NULL, rpmsg_chrdev_eptdev_destroy); >> + if (ret) >> + dev_warn(&rpdev->dev, "failed to destroy endpoints: %d\n", ret); >> +} >> + >> +static struct rpmsg_device_id rpmsg_chrdev_id_table[] = { >> + { .name = "rpmsg-raw" }, >> + { }, >> +}; >> + >> +static struct rpmsg_driver rpmsg_chrdev_driver = { >> + .probe = rpmsg_chrdev_probe, >> + .remove = rpmsg_chrdev_remove, >> + .id_table = rpmsg_chrdev_id_table, >> + .drv.name = "rpmsg_chrdev", >> +}; >> + >> static int rpmsg_chrdev_init(void) >> { >> int ret; >> @@ -442,12 +494,24 @@ static int rpmsg_chrdev_init(void) >> return ret; >> } >> >> + ret = register_rpmsg_driver(&rpmsg_chrdev_driver); >> + if (ret < 0) { >> + pr_err("rpmsg: failed to register rpmsg raw driver\n"); >> + goto free_region; >> + } >> + >> return 0; >> + >> +free_region: >> + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); >> + >> + return ret; >> } >> postcore_initcall(rpmsg_chrdev_init); >> >> static void rpmsg_chrdev_exit(void) >> { >> + unregister_rpmsg_driver(&rpmsg_chrdev_driver); >> unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); >> } >> module_exit(rpmsg_chrdev_exit); >> diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c >> index 59d2bd264fdb..298e75dc7774 100644 >> --- a/drivers/rpmsg/rpmsg_ctrl.c >> +++ b/drivers/rpmsg/rpmsg_ctrl.c >> @@ -10,6 +10,9 @@ >> * Based on rpmsg performance statistics driver by Michal Simek, which in turn >> * was based on TI & Google OMX rpmsg driver. >> */ >> + >> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt >> + >> #include <linux/cdev.h> >> #include <linux/device.h> >> #include <linux/fs.h> >> @@ -193,13 +196,13 @@ static int rpmsg_ctrldev_init(void) >> >> ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg_ctrl"); >> if (ret < 0) { >> - pr_err("rpmsg: failed to allocate char dev region\n"); >> + pr_err("failed to allocate char dev region\n"); >> return ret; >> } >> >> ret = register_rpmsg_driver(&rpmsg_ctrldev_driver); >> if (ret < 0) { >> - pr_err("rpmsg ctrl: failed to register rpmsg driver\n"); >> + pr_err("failed to register rpmsg driver\n"); >> unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); >> } >> >> -- >> 2.17.1 >>
diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c index 6a01e8e1c111..dd754c870ba1 100644 --- a/drivers/rpmsg/rpmsg_char.c +++ b/drivers/rpmsg/rpmsg_char.c @@ -432,6 +432,58 @@ int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent } EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create); +static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev) +{ + struct rpmsg_channel_info chinfo; + struct rpmsg_eptdev *eptdev; + struct device *dev = &rpdev->dev; + + memcpy(chinfo.name, rpdev->id.name, RPMSG_NAME_SIZE); + chinfo.src = rpdev->src; + chinfo.dst = rpdev->dst; + + eptdev = rpmsg_chrdev_eptdev_alloc(rpdev, dev); + if (IS_ERR(eptdev)) + return PTR_ERR(eptdev); + + /* + * Create the default endpoint associated to the rpmsg device and provide rpmsg_eptdev + * structure as callback private data. + * Do not allow the creation and release of an endpoint on /dev/rpmsgX open and close, + * reuse the default endpoint instead + */ + eptdev->default_ept = rpmsg_create_default_ept(rpdev, rpmsg_ept_cb, eptdev, chinfo); + if (!eptdev->default_ept) { + dev_err(&rpdev->dev, "failed to create %s\n", chinfo.name); + put_device(dev); + kfree(eptdev); + return -EINVAL; + } + + return rpmsg_chrdev_eptdev_add(eptdev, chinfo); +} + +static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev) +{ + int ret; + + ret = device_for_each_child(&rpdev->dev, NULL, rpmsg_chrdev_eptdev_destroy); + if (ret) + dev_warn(&rpdev->dev, "failed to destroy endpoints: %d\n", ret); +} + +static struct rpmsg_device_id rpmsg_chrdev_id_table[] = { + { .name = "rpmsg-raw" }, + { }, +}; + +static struct rpmsg_driver rpmsg_chrdev_driver = { + .probe = rpmsg_chrdev_probe, + .remove = rpmsg_chrdev_remove, + .id_table = rpmsg_chrdev_id_table, + .drv.name = "rpmsg_chrdev", +}; + static int rpmsg_chrdev_init(void) { int ret; @@ -442,12 +494,24 @@ static int rpmsg_chrdev_init(void) return ret; } + ret = register_rpmsg_driver(&rpmsg_chrdev_driver); + if (ret < 0) { + pr_err("rpmsg: failed to register rpmsg raw driver\n"); + goto free_region; + } + return 0; + +free_region: + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); + + return ret; } postcore_initcall(rpmsg_chrdev_init); static void rpmsg_chrdev_exit(void) { + unregister_rpmsg_driver(&rpmsg_chrdev_driver); unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); } module_exit(rpmsg_chrdev_exit); diff --git a/drivers/rpmsg/rpmsg_ctrl.c b/drivers/rpmsg/rpmsg_ctrl.c index 59d2bd264fdb..298e75dc7774 100644 --- a/drivers/rpmsg/rpmsg_ctrl.c +++ b/drivers/rpmsg/rpmsg_ctrl.c @@ -10,6 +10,9 @@ * Based on rpmsg performance statistics driver by Michal Simek, which in turn * was based on TI & Google OMX rpmsg driver. */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/cdev.h> #include <linux/device.h> #include <linux/fs.h> @@ -193,13 +196,13 @@ static int rpmsg_ctrldev_init(void) ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg_ctrl"); if (ret < 0) { - pr_err("rpmsg: failed to allocate char dev region\n"); + pr_err("failed to allocate char dev region\n"); return ret; } ret = register_rpmsg_driver(&rpmsg_ctrldev_driver); if (ret < 0) { - pr_err("rpmsg ctrl: failed to register rpmsg driver\n"); + pr_err("failed to register rpmsg driver\n"); unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX); }
Allows to probe the endpoint device on a remote name service announcement, by registering a rpmsg_driverfor the "rpmsg-raw" channel. With this patch the /dev/rpmsgX interface can be instantiated by the remote firmware. Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com> --- drivers/rpmsg/rpmsg_char.c | 64 ++++++++++++++++++++++++++++++++++++++ drivers/rpmsg/rpmsg_ctrl.c | 7 +++-- 2 files changed, 69 insertions(+), 2 deletions(-)