[PATCH v7 5/7] qcom: cpuidle: Add cpuidle driver for QCOM cpus

Stephen Boyd
2014-09-29T23:18:46Z

On 09/26/14 17:58, Lina Iyer wrote:
> diff --git a/drivers/cpuidle/cpuidle-qcom.c b/drivers/cpuidle/cpuidle-qcom.c
> new file mode 100644
> index 0000000..2fcf79a
> --- /dev/null
> +++ b/drivers/cpuidle/cpuidle-qcom.c
> @@ -0,0 +1,89 @@
> +/*
> + * 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/cpu_pm.h>
> +#include <linux/cpuidle.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +
> +#include <soc/qcom/pm.h>
> +#include "dt_idle_states.h"
> +
> +static void (*qcom_idle_enter)(enum pm_sleep_mode);
> +
> +static int qcom_lpm_enter_wfi(struct cpuidle_device *dev,
> + struct cpuidle_driver *drv, int index)
> +{
> + qcom_idle_enter(PM_SLEEP_MODE_WFI);

Why can't we just pass index here? It would be nice to not need to
include soc/qcom/pm.h in this file.

> +
> + return index;
> +}
> +
> +static int qcom_lpm_enter_spc(struct cpuidle_device *dev,
> + struct cpuidle_driver *drv, int index)
> +{
> + cpu_pm_enter();
> + qcom_idle_enter(PM_SLEEP_MODE_SPC);
> + cpu_pm_exit();
> +
> + return index;
> +}
> +
> +static struct cpuidle_driver qcom_cpuidle_driver = {
> + .name = "qcom_cpuidle",
> + .owner = THIS_MODULE,
> +};
> +
> +static const struct of_device_id qcom_idle_state_match[] __initconst = {
> + { .compatible = "qcom,idle-state-wfi", .data = qcom_lpm_enter_wfi },
> + { .compatible = "qcom,idle-state-spc", .data = qcom_lpm_enter_spc },
> + { },
> +};
> +
> +static int qcom_cpuidle_probe(struct platform_device *pdev)
> +{
> + struct cpuidle_driver *drv = &qcom_cpuidle_driver;
> + int ret;
> +
> + qcom_idle_enter = (void *)(pdev->dev.platform_data);
> + if (!qcom_idle_enter)
> + return -EFAULT;

Error code looks a little wrong. -ENODEV?

> +
> + /* Probe for other states including platform WFI */
> + ret = dt_init_idle_driver(drv, qcom_idle_state_match, 0);
> + if (ret <= 0) {
> + pr_err("%s: No cpuidle state found.\n", __func__);

This would be true if ret == 0, but if it's < 0 that isn't true. Drop
the print?

> + return ret;
> + }
> +
> + ret = cpuidle_register(drv, NULL);
> + if (ret) {
> + pr_err("%s: failed to register cpuidle driver\n", __func__);

This seems redundant given that cpuidle_register() already prints an
error when it fails.

> + return ret;
> + }
> +
> + return 0;

Could just be return cpuidle_register(drv, NULL);

--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
hosted by The Linux Foundation