Re: [PATCH v9 6/9] qcom: cpuidle: Add cpuidle driver for QCOM cpus

[Daniel Lezcano <daniel.lezcano@linaro.org>]

On 10/25/2014 01:40 AM, Lina Iyer wrote:
> Add cpuidle driver interface to allow cpus to go into C-States. Use the
> cpuidle DT interface, common across ARM architectures, to provide the
> C-State information to the cpuidle framework.
>
> Supported modes at this time are Standby and Standalone Power Collapse.
>
> Signed-off-by: Lina Iyer <lina.iyer@linaro.org>

A few comments below, otherwise it looks good to me.


> ---

[ ... ]

> +[1]. Documentation/devicetree/bindings/arm/idle-states.txt
> diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm
> index 8c16ab2..13c7c1f 100644
> --- a/drivers/cpuidle/Kconfig.arm
> +++ b/drivers/cpuidle/Kconfig.arm
> @@ -63,3 +63,10 @@ config ARM_MVEBU_V7_CPUIDLE
>   	depends on ARCH_MVEBU
>   	help
>   	  Select this to enable cpuidle on Armada 370, 38x and XP processors.
> +
> +config ARM_QCOM_CPUIDLE
> +	bool "CPU Idle drivers for Qualcomm processors"
> +	depends on QCOM_PM

Could you stick to the ARCH dependency as the other drivers ?

> +	select DT_IDLE_STATES
> +	help
> +	  Select this to enable cpuidle for QCOM processors
> diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
> index 4d177b9..6c222d5 100644
> --- a/drivers/cpuidle/Makefile
> +++ b/drivers/cpuidle/Makefile
> @@ -17,6 +17,7 @@ obj-$(CONFIG_ARM_ZYNQ_CPUIDLE)		+= cpuidle-zynq.o
>   obj-$(CONFIG_ARM_U8500_CPUIDLE)         += cpuidle-ux500.o
>   obj-$(CONFIG_ARM_AT91_CPUIDLE)          += cpuidle-at91.o
>   obj-$(CONFIG_ARM_EXYNOS_CPUIDLE)        += cpuidle-exynos.o
> +obj-$(CONFIG_ARM_QCOM_CPUIDLE)		+= cpuidle-qcom.o
>
>   ###############################################################################
>   # MIPS drivers
> diff --git a/drivers/cpuidle/cpuidle-qcom.c b/drivers/cpuidle/cpuidle-qcom.c
> new file mode 100644
> index 0000000..1c1dcbc
> --- /dev/null
> +++ b/drivers/cpuidle/cpuidle-qcom.c
> @@ -0,0 +1,72 @@
> +/*
> + * Copyright (c) 2014, Linaro Limited.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + */
> +
> +#include <linux/cpuidle.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +
> +#include <soc/qcom/pm.h>
> +#include "dt_idle_states.h"
> +
> +static struct qcom_cpu_pm_ops *lpm_ops;
> +
> +static int qcom_cpu_stby(struct cpuidle_device *dev,
> +				struct cpuidle_driver *drv, int index)
> +{
> +	lpm_ops->standby(NULL);

No check ?

> +	return index;
> +}
> +
> +static int qcom_cpu_spc(struct cpuidle_device *dev,
> +				struct cpuidle_driver *drv, int index)
> +{
> +	lpm_ops->spc(NULL);

No check ?

> +	return index;
> +}
> +
> +static struct cpuidle_driver qcom_cpuidle_driver = {
> +	.name	= "qcom_cpuidle",
> +};
> +
> +static const struct of_device_id qcom_idle_state_match[] = {
> +	{ .compatible = "qcom,idle-state-stby", .data = qcom_cpu_stby},
> +	{ .compatible = "qcom,idle-state-spc", .data = qcom_cpu_spc },
> +	{ },
> +};
> +
> +static int qcom_cpuidle_probe(struct platform_device *pdev)
> +{
> +	struct cpuidle_driver *drv = &qcom_cpuidle_driver;
> +	int ret;
> +
> +	lpm_ops = pdev->dev.platform_data;
> +
> +	/* Probe for other states, including standby */
> +	ret = dt_init_idle_driver(drv, qcom_idle_state_match, 0);
> +	if (ret < 0)
> +		return ret;
> +
> +	return cpuidle_register(drv, NULL);
> +}
> +
> +static struct platform_driver qcom_cpuidle_plat_driver = {
> +	.probe	= qcom_cpuidle_probe,
> +	.driver = {
> +		.name = "qcom_cpuidle",
> +	},
> +};
> +
> +module_platform_driver(qcom_cpuidle_plat_driver);
>


-- 
  <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog