linux-kernel - Re: [RFT PATCH 3/9] drivers: qcom: rpmh-rsc: Fold tcs_ctrl

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Date:   Wed, 11 Mar 2020 15:20:38 +0530
From:   Maulik Shah <mkshah@...eaurora.org>
To:     Douglas Anderson <dianders@...omium.org>,
        Andy Gross <agross@...nel.org>,
        Bjorn Andersson <bjorn.andersson@...aro.org>
Cc:     Rajendra Nayak <rnayak@...eaurora.org>, mka@...omium.org,
        evgreen@...omium.org, swboyd@...omium.org,
        Lina Iyer <ilina@...eaurora.org>,
        linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [RFT PATCH 3/9] drivers: qcom: rpmh-rsc: Fold tcs_ctrl_write()
 into its single caller

Hi,

On 3/7/2020 5:29 AM, Douglas Anderson wrote:
> I was trying to write documentation for the functions in rpmh-rsc and
> I got to tcs_ctrl_write().  The documentation for the function would
> have been: "This is the core of rpmh_rsc_write_ctrl_data(); all the
> caller does is error-check and then call this".
>
> Having the error checks in a separate function doesn't help for
> anything since:
> - There are no other callers that need to bypass the error checks.
> - It's less documenting.  When I read tcs_ctrl_write() I kept
>   wondering if I need to handle cases other than ACTIVE_ONLY or cases
>   with more commands than could fit in a TCS.  This is obvious when
>   the error checks and code are together.
> - The function just isn't that long, so there's no problem
>   understanding the combined function.
>
> Things were even more confusing because the two functions names didn't
> make it obvious (at least to me) their relationship.
>
> Simplify by folding one function into the other.
>
> Signed-off-by: Douglas Anderson <dianders@...omium.org>
> ---
>
>  drivers/soc/qcom/rpmh-rsc.c | 39 ++++++++++++++++---------------------
>  1 file changed, 17 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c
> index 0a409988d103..099603bf14bf 100644
> --- a/drivers/soc/qcom/rpmh-rsc.c
> +++ b/drivers/soc/qcom/rpmh-rsc.c
> @@ -549,27 +549,6 @@ static int find_slots(struct tcs_group *tcs, const struct tcs_request *msg,
>  	return 0;
>  }
>  
> -static int tcs_ctrl_write(struct rsc_drv *drv, const struct tcs_request *msg)
> -{
> -	struct tcs_group *tcs;
> -	int tcs_id = 0, cmd_id = 0;
> -	unsigned long flags;
> -	int ret;
> -
> -	tcs = get_tcs_for_msg(drv, msg);
> -	if (IS_ERR(tcs))
> -		return PTR_ERR(tcs);
> -
> -	spin_lock_irqsave(&tcs->lock, flags);
> -	/* find the TCS id and the command in the TCS to write to */
> -	ret = find_slots(tcs, msg, &tcs_id, &cmd_id);
> -	if (!ret)
> -		__tcs_buffer_write(drv, tcs_id, cmd_id, msg);
> -	spin_unlock_irqrestore(&tcs->lock, flags);
> -
> -	return ret;
> -}
> -
>  /**
>   * rpmh_rsc_write_ctrl_data: Write request to the controller
>   *
> @@ -580,6 +559,11 @@ static int tcs_ctrl_write(struct rsc_drv *drv, const struct tcs_request *msg)
>   */
>  int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg)
>  {
> +	struct tcs_group *tcs;
> +	int tcs_id = 0, cmd_id = 0;
> +	unsigned long flags;
> +	int ret;
> +
>  	if (!msg || !msg->cmds || !msg->num_cmds ||
>  	    msg->num_cmds > MAX_RPMH_PAYLOAD) {
>  		pr_err("Payload error\n");
> @@ -590,7 +574,18 @@ int rpmh_rsc_write_ctrl_data(struct rsc_drv *drv, const struct tcs_request *msg)
>  	if (msg->state == RPMH_ACTIVE_ONLY_STATE)
>  		return -EINVAL;
>  
> -	return tcs_ctrl_write(drv, msg);
> +	tcs = get_tcs_for_msg(drv, msg);
> +	if (IS_ERR(tcs))
> +		return PTR_ERR(tcs);
> +
> +	spin_lock_irqsave(&tcs->lock, flags);
> +	/* find the TCS id and the command in the TCS to write to */
> +	ret = find_slots(tcs, msg, &tcs_id, &cmd_id);
> +	if (!ret)
> +		__tcs_buffer_write(drv, tcs_id, cmd_id, msg);
> +	spin_unlock_irqrestore(&tcs->lock, flags);
> +
> +	return ret;
>  }
>  
>  static int rpmh_probe_tcs_config(struct platform_device *pdev,
i am ok with this change.

Reviewed-by: Maulik Shah <mkshah@...eaurora.org>

Thanks,
Maulik

-- 
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