Re: [PATCH v3 3/8] phy: qcom-qmp: Fix phy pipe clock name

From: Vivek Gautam <vivek.gautam@codeaurora.org>
To: Varadarajan Narayanan <varada@codeaurora.org>,
	bhelgaas@google.com, robh+dt@kernel.org, mark.rutland@arm.com,
	svarbanov@mm-sol.com, kishon@ti.com, sboyd@codeaurora.org,
	fengguang.wu@intel.com, weiyongjun1@huawei.com,
	linux-pci@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org
Subject: Re: [PATCH v3 3/8] phy: qcom-qmp: Fix phy pipe clock name
Date: Fri, 21 Jul 2017 13:31:08 +0530	[thread overview]
Message-ID: <84142e2d-39e1-082c-f3eb-6bb66baa8508@codeaurora.org> (raw)
In-Reply-To: <1500528880-25804-4-git-send-email-varada@codeaurora.org>

Hi,

On 07/20/2017 11:04 AM, Varadarajan Narayanan wrote:
> Presently, the phy pipe clock's name is assumed to be either
> usb3_phy_pipe_clk_src or pcie_XX_pipe_clk_src (where XX is the
> phy lane's number). However, this will not work if an SoC has
> more than one instance of the phy. Hence, instead of assuming
> the name of the clock, fetch it from the DT.
>
> Acked-by: Vivek Gautam <vivek.gautam@codeaurora.org>
> Signed-off-by: Varadarajan Narayanan <varada@codeaurora.org>
> ---
>   drivers/phy/qualcomm/phy-qcom-qmp.c | 28 ++++++++++++++++------------
>   1 file changed, 16 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp.c b/drivers/phy/qualcomm/phy-qcom-qmp.c
> index 78ca628..97020ec 100644
> --- a/drivers/phy/qualcomm/phy-qcom-qmp.c
> +++ b/drivers/phy/qualcomm/phy-qcom-qmp.c
> @@ -925,20 +925,13 @@ static int qcom_qmp_phy_clk_init(struct device *dev)
>    *    clk  |   +-------+   |                   +-----+
>    *         +---------------+
>    */
> -static int phy_pipe_clk_register(struct qcom_qmp *qmp, int id)
> +static int phy_pipe_clk_register(struct qcom_qmp *qmp, const char *clk_name)
>   {
> -	char name[24];
>   	struct clk_fixed_rate *fixed;
>   	struct clk_init_data init = { };
>   
> -	switch (qmp->cfg->type) {
> -	case PHY_TYPE_USB3:
> -		snprintf(name, sizeof(name), "usb3_phy_pipe_clk_src");
> -		break;
> -	case PHY_TYPE_PCIE:
> -		snprintf(name, sizeof(name), "pcie_%d_pipe_clk_src", id);
> -		break;
> -	default:
> +	if ((qmp->cfg->type != PHY_TYPE_USB3) &&
> +	    (qmp->cfg->type != PHY_TYPE_PCIE)) {
>   		/* not all phys register pipe clocks, so return success */
>   		return 0;
>   	}
> @@ -947,7 +940,7 @@ static int phy_pipe_clk_register(struct qcom_qmp *qmp, int id)
>   	if (!fixed)
>   		return -ENOMEM;
>   
> -	init.name = name;
> +	init.name = clk_name;
>   	init.ops = &clk_fixed_rate_ops;
>   
>   	/* controllers using QMP phys use 125MHz pipe clock interface */
> @@ -1110,6 +1103,8 @@ static int qcom_qmp_phy_probe(struct platform_device *pdev)
>   
>   	id = 0;
>   	for_each_available_child_of_node(dev->of_node, child) {
> +		const char *clk_name;
> +
>   		/* Create per-lane phy */
>   		ret = qcom_qmp_phy_create(dev, child, id);
>   		if (ret) {
> @@ -1118,11 +1113,20 @@ static int qcom_qmp_phy_probe(struct platform_device *pdev)
>   			return ret;
>   		}
>   
> +		ret = of_property_read_string(child, "clock-output-names",
> +							&clk_name);
> +		if (ret) {

Sorry, missed this earlier.
You shouldn't error out for phys that don't expose 'clock-output'.
So returning success in case the property doesn't exist for particular 
phys makes sense.
And again for usb and pcie this property becomes mandatory.

Regards
Vivek

> +			dev_err(dev,
> +				"failed to get clock-output-names for lane%d phy, %d\n",
> +				id, ret);
> +			return ret;
> +		}
> +
>   		/*
>   		 * Register the pipe clock provided by phy.
>   		 * See function description to see details of this pipe clock.
>   		 */
> -		ret = phy_pipe_clk_register(qmp, id);
> +		ret = phy_pipe_clk_register(qmp, clk_name);
>   		if (ret) {
>   			dev_err(qmp->dev,
>   				"failed to register pipe clock source\n");

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