lkml.org 
[lkml]   [2007]   [Oct]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH try #3] Input/Joystick Driver: add support AD7142 joystick driver
Hi Bryan,

On 10/15/07, Bryan Wu <bryan.wu@analog.com> wrote:
> +
> +static int ad7142_thread(void *nothing)
> +{
> + do {
> + wait_for_completion(&ad7142_completion);
> + ad7142_decode();
> + enable_irq(CONFIG_BFIN_JOYSTICK_IRQ_PFX);
> + } while (!kthread_should_stop());
> +

No, this is not going to work well:
- you at least need to reinitialize the completion before enabling
IRQ, otherwise you will spin in a very tight loop
- if noone would touch the joystick ad7142_clsoe would() block
infinitely because noone would signal the completion and
ad7142_thread() would never stop.

Completion is just not a good abstraction here... Please use work
abstraction and possibly a separate workqueue.

> +
> + ad7142_task = kthread_run(ad7142_thread, NULL, "ad7142_task");
> + if (IS_ERR(ad7142_task)) {
> + printk(KERN_ERR "serio: Failed to start kseriod\n");

kseriod?

> + return PTR_ERR(ad7142_task);
> + }
> + return 0;
> +}
> +
> +static void ad7142_close(struct input_dev *dev)
> +{

Don't you need to write something over i2c to tell the device to shut
down? As it is now I expect the device to continue raising its IRQ
until kernel decides that it is unhandled and should be ignored.

> + free_irq(CONFIG_BFIN_JOYSTICK_IRQ_PFX, ad7142_interrupt);

Ok, so you freeing IRQ here, but it is allocated in ad7142_probe().
What happen if you try to open device after it was closed?

> + kthread_stop(ad7142_task);
> +}
> +
> +static int __init ad7142_init(void)
> +{
> + return i2c_add_driver(&ad7142_driver);
> +}
> +
> +static void __exit ad7142_exit(void)
> +{
> + i2c_del_driver(&ad7142_driver);
> + input_unregister_device(ad7142_dev);

input_unregister_device() should be in ad7142_detach_client? I am not
sure i2c - there seems to be 2 interface styles and you probably need
to use the new one. I am CC-inj Jean on this.

> +}
> +
> +module_init(ad7142_init);
> +module_exit(ad7142_exit);
> --
> 1.5.3.4
>


--
Dmitry
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-10-15 17:51    [W:0.112 / U:0.388 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site