Re: [PATCH V7 1/2] soc: qcom: aoss: Expose send for generic usecase

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Mon 30 Aug 06:37 CDT 2021, Deepak Kumar Singh wrote:

> Not all upcoming usecases will have an interface to allow the aoss
> driver to hook onto. Expose the send api and create a get function to
> enable drivers to send their own messages to aoss.
> 
> Signed-off-by: Chris Lew <clew@codeaurora.org>
> Signed-off-by: Deepak Kumar Singh <deesin@codeaurora.org>
> Reviewed-by: Stephen Boyd <swboyd@chromium.org>
> ---
>  drivers/soc/qcom/qcom_aoss.c       | 54 +++++++++++++++++++++++++++++++++++++-
>  include/linux/soc/qcom/qcom_aoss.h | 38 +++++++++++++++++++++++++++
>  2 files changed, 91 insertions(+), 1 deletion(-)
>  create mode 100644 include/linux/soc/qcom/qcom_aoss.h
> 
> diff --git a/drivers/soc/qcom/qcom_aoss.c b/drivers/soc/qcom/qcom_aoss.c
> index 934fcc4..bf0a6280 100644
> --- a/drivers/soc/qcom/qcom_aoss.c
> +++ b/drivers/soc/qcom/qcom_aoss.c
> @@ -8,10 +8,12 @@
>  #include <linux/io.h>
>  #include <linux/mailbox_client.h>
>  #include <linux/module.h>
> +#include <linux/of_platform.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_domain.h>
>  #include <linux/thermal.h>
>  #include <linux/slab.h>
> +#include <linux/soc/qcom/qcom_aoss.h>
>  
>  #define QMP_DESC_MAGIC			0x0
>  #define QMP_DESC_VERSION		0x4
> @@ -223,11 +225,14 @@ static bool qmp_message_empty(struct qmp *qmp)
>   *
>   * Return: 0 on success, negative errno on failure
>   */
> -static int qmp_send(struct qmp *qmp, const void *data, size_t len)
> +int qmp_send(struct qmp *qmp, const void *data, size_t len)
>  {
>  	long time_left;
>  	int ret;
>  
> +	if (WARN_ON(IS_ERR_OR_NULL(qmp) || !data))
> +		return -EINVAL;
> +
>  	if (WARN_ON(len + sizeof(u32) > qmp->size))
>  		return -EINVAL;
>  
> @@ -261,6 +266,7 @@ static int qmp_send(struct qmp *qmp, const void *data, size_t len)
>  
>  	return ret;
>  }
> +EXPORT_SYMBOL(qmp_send);
>  
>  static int qmp_qdss_clk_prepare(struct clk_hw *hw)
>  {
> @@ -515,6 +521,51 @@ static void qmp_cooling_devices_remove(struct qmp *qmp)
>  		thermal_cooling_device_unregister(qmp->cooling_devs[i].cdev);
>  }
>  
> +/**
> + * qmp_get() - get a qmp handle from a device
> + * @dev: client device pointer
> + *
> + * Return: handle to qmp device on success, ERR_PTR() on failure
> + */
> +struct qmp *qmp_get(struct device *dev)
> +{
> +	struct platform_device *pdev;
> +	struct device_node *np;
> +	struct qmp *qmp;
> +
> +	if (!dev || !dev->of_node)
> +		return ERR_PTR(-EINVAL);
> +
> +	np = of_parse_phandle(dev->of_node, "qcom,qmp", 0);
> +	if (!np)
> +		return ERR_PTR(-ENODEV);
> +
> +	pdev = of_find_device_by_node(np);
> +	of_node_put(np);
> +	if (!pdev)
> +		return ERR_PTR(-EINVAL);
> +
> +	qmp = platform_get_drvdata(pdev);
> +
> +	return qmp ? qmp : ERR_PTR(-EPROBE_DEFER);
> +}
> +EXPORT_SYMBOL(qmp_get);
> +
> +/**
> + * qmp_put() - release a qmp handle
> + * @qmp: qmp handle obtained from qmp_get()
> + */
> +void qmp_put(struct qmp *qmp)
> +{
> +	if (!IS_ERR_OR_NULL(qmp))
> +		put_device(qmp->dev);
> +	/*
> +	 * Match get_device() inside of_find_device_by_node() in
> +	 * qmp_get()
> +	 */

Afaict this comment relates to the put_device() above, which typically
would imply that the comment should be above or inside the if
statement?

> +}
> +EXPORT_SYMBOL(qmp_put);
> +

Regards,
Bjorn

>  static int qmp_probe(struct platform_device *pdev)
>  {
>  	struct resource *res;
> @@ -610,6 +661,7 @@ static struct platform_driver qmp_driver = {
>  	.driver = {
>  		.name		= "qcom_aoss_qmp",
>  		.of_match_table	= qmp_dt_match,
> +		.suppress_bind_attrs = true,
>  	},
>  	.probe = qmp_probe,
>  	.remove	= qmp_remove,
> diff --git a/include/linux/soc/qcom/qcom_aoss.h b/include/linux/soc/qcom/qcom_aoss.h
> new file mode 100644
> index 0000000..3c2a82e
> --- /dev/null
> +++ b/include/linux/soc/qcom/qcom_aoss.h
> @@ -0,0 +1,38 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Copyright (c) 2021, The Linux Foundation. All rights reserved.
> + */
> +
> +#ifndef __QCOM_AOSS_H__
> +#define __QCOM_AOSS_H__
> +
> +#include <linux/err.h>
> +#include <linux/device.h>
> +
> +struct qmp;
> +
> +#if IS_ENABLED(CONFIG_QCOM_AOSS_QMP)
> +
> +int qmp_send(struct qmp *qmp, const void *data, size_t len);
> +struct qmp *qmp_get(struct device *dev);
> +void qmp_put(struct qmp *qmp);
> +
> +#else
> +
> +static inline int qmp_send(struct qmp *qmp, const void *data, size_t len)
> +{
> +	return -ENODEV;
> +}
> +
> +static inline struct qmp *qmp_get(struct device *dev)
> +{
> +	return ERR_PTR(-ENODEV);
> +}
> +
> +static inline void qmp_put(struct qmp *qmp)
> +{
> +}
> +
> +#endif
> +
> +#endif
> -- 
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> a Linux Foundation Collaborative Project
>