On 4/21/21 8:04 PM, Mathieu Poirier wrote:
> On Tue, Apr 13, 2021 at 03:44:53PM +0200, Arnaud Pouliquen wrote:
>> Create the rpmsg_ctrl.c module and move the code related to the
>> rpmsg_ctrldev device in this new module.
>>
>> Add the dependency between rpmsg_char and rpmsg_ctrl in the
>> kconfig file.
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
>> ---
>> update from v1:
>> - keep "rpmsg_chrdev" driver name in rpmsg_ctrl, driver will be renamed
>> in next path that renames the rpmsg_chrdev_create_eptdev.
>> - rename the chardev regions
>> - move RPMSG_DEV_MAX to rpmsg_char.h
>> ---
>> drivers/rpmsg/Kconfig | 9 ++
>> drivers/rpmsg/Makefile | 1 +
>> drivers/rpmsg/rpmsg_char.c | 181 +----------------------------
>> drivers/rpmsg/rpmsg_char.h | 2 +
>> drivers/rpmsg/rpmsg_ctrl.c | 231 +++++++++++++++++++++++++++++++++++++
>> 5 files changed, 245 insertions(+), 179 deletions(-)
>> create mode 100644 drivers/rpmsg/rpmsg_ctrl.c
>>
>> diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig
>> index 0b4407abdf13..d822ec9ec692 100644
>> --- a/drivers/rpmsg/Kconfig
snip[...]
>> +static int rpmsg_ctrldev_init(void)
>> +{
>> + int ret;
>> +
>> + 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");
>> + return ret;
>> + }
>> +
>> + rpmsg_class = class_create(THIS_MODULE, "rpmsg");
>
> This class thing really bothers me. Keeping this here means that rpmsg_eptdevs
> created from user space will be associated to this rpmsg_class but those created
> from the name service won't. As such I propose to move this to rpmsg_char and
> simply not associate the control device to the class.
>
> Otherwise we'd have to introduce some mechanic only to deal with the creation of
> the class and I don't think it is worth. We can revise that approach if someone
> complains we broke their user space.
I agree with that as it was my first proposed approach here [1]
[1] https://www.spinics.net/lists/linux-arm-msm/msg81194.html
Thanks,
Arnaud
>
>
>> + if (IS_ERR(rpmsg_class)) {
>> + pr_err("failed to create rpmsg class\n");
>> + ret = PTR_ERR(rpmsg_class);
>> + goto free_region;
>> + }
>> +
>> + ret = register_rpmsg_driver(&rpmsg_ctrldev_driver);
>> + if (ret < 0) {
>> + pr_err("rpmsg ctrl: failed to register rpmsg driver\n");
>> + goto free_class;
>> + }
>> +
>> + return 0;
>> +
>> +free_class:
>> + class_destroy(rpmsg_class);
>> +free_region:
>> + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
>> +
>> + return ret;
>> +}
>> +postcore_initcall(rpmsg_ctrldev_init);
>> +
>> +static void rpmsg_ctrldev_exit(void)
>> +{
>> + unregister_rpmsg_driver(&rpmsg_ctrldev_driver);
>> + class_destroy(rpmsg_class);
>> + unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
>> +}
>> +module_exit(rpmsg_ctrldev_exit);
>> +
>> +MODULE_DESCRIPTION("rpmsg control interface");
>> +MODULE_ALIAS("rpmsg:" KBUILD_MODNAME);
>> +MODULE_LICENSE("GPL v2");
>> --
>> 2.17.1
>>
