On Tue, May 01, 2012 at 09:12:38PM -0500, Robert Lee wrote:
> Add common cpuidle init functionality that can be used by various
> imx platforms.
> 
> Signed-off-by: Robert Lee <rob....@linaro.org>
> ---
> +
> +int __init imx_cpuidle_init(struct cpuidle_driver *drv)
> +{
> +     struct cpuidle_device *dev;
> +     int cpu_id, ret;
> +
> +     if (!drv || drv->state_count > CPUIDLE_STATE_MAX) {

Please don't check for !drv here. When someone calls this function with
a NULL pointer he should get a nive stack trace allowing him to figure
out what went wrong.

> +             pr_err("%s: Invalid Input\n", __func__);
> +             return -EINVAL;
> +     }
> +
> +     ret = cpuidle_register_driver(drv);
> +     if (ret) {
> +             pr_err("%s: Failed to register cpuidle driver with error: %d\n",
> +                      __func__, ret);
> +             return ret;
> +     }
> +
> +     imx_cpuidle_devices = alloc_percpu(struct cpuidle_device);
> +     if (imx_cpuidle_devices == NULL) {
> +             ret = -ENOMEM;
> +             goto unregister_drv;
> +     }
> +
> +     /* initialize state data for each cpuidle_device */
> +     for_each_possible_cpu(cpu_id) {
> +             dev = per_cpu_ptr(imx_cpuidle_devices, cpu_id);
> +             dev->cpu = cpu_id;
> +             dev->state_count = drv->state_count;
> +
> +             ret = cpuidle_register_device(dev);
> +             if (ret) {
> +                     pr_err("%s: Failed to register cpu %u\n",
> +                             __func__, cpu_id);
> +                     goto uninit;

You should only unregister the cpuidle devices you successfully
registered. Unregistering not yet registered cpuidle devices probably
has unwanted side effects.

Sascha

> +             }
> +     }
> +
> +     return 0;
> +
> +uninit:
> +     imx_cpuidle_devices_uninit();
> +
> +unregister_drv:
> +     cpuidle_unregister_driver(drv);
> +     return ret;
> +}
> diff --git a/arch/arm/plat-mxc/include/mach/cpuidle.h 
> b/arch/arm/plat-mxc/include/mach/cpuidle.h
> new file mode 100644
> index 0000000..8612510
> --- /dev/null
> +++ b/arch/arm/plat-mxc/include/mach/cpuidle.h
> @@ -0,0 +1,22 @@
> +/*
> + * Copyright 2012 Freescale Semiconductor, Inc.
> + * Copyright 2012 Linaro Ltd.
> + *
> + * The code contained herein is licensed under the GNU General Public
> + * License. You may obtain a copy of the GNU General Public License
> + * Version 2 or later at the following locations:
> + *
> + * http://www.opensource.org/licenses/gpl-license.html
> + * http://www.gnu.org/copyleft/gpl.html
> + */
> +
> +#include <linux/cpuidle.h>
> +
> +#ifdef CONFIG_CPU_IDLE
> +extern void imx_cpuidle_devices_uninit(void);
> +extern int imx_cpuidle_init(struct cpuidle_driver *drv);
> +#else
> +static inline void imx_cpuidle_devices_uninit(void) {}
> +static inline int imx_cpuidle_init(struct cpuidle_driver *drv)
> +{ return -ENODEV; }
> +#endif
> -- 
> 1.7.10
> 
> 

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

_______________________________________________
linaro-dev mailing list
linaro-dev@lists.linaro.org
http://lists.linaro.org/mailman/listinfo/linaro-dev

Reply via email to