Re: [PATCH 20/21] phy: Add support for Qualcomm's USB HSIC phy

Neil Armstrong
2016-06-28T08:49:45Z

On 06/26/2016 09:28 AM, Stephen Boyd wrote:
> The HSIC USB controller on qcom SoCs has an integrated all
> digital phy controlled via the ULPI viewport.
>
> Cc: Kishon Vijay Abraham I <kishon@ti.com>
> Cc: <devicetree@vger.kernel.org>
> Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
> ---
> .../devicetree/bindings/phy/qcom,usb-hsic-phy.txt | 60 ++++++++
> drivers/phy/Kconfig | 7 +
> drivers/phy/Makefile | 1 +
> drivers/phy/phy-qcom-usb-hsic.c | 161 +++++++++++++++++++++
> 4 files changed, 229 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/phy/qcom,usb-hsic-phy.txt
> create mode 100644 drivers/phy/phy-qcom-usb-hsic.c
>
> diff --git a/Documentation/devicetree/bindings/phy/qcom,usb-hsic-phy.txt b/Documentation/devicetree/bindings/phy/qcom,usb-hsic-phy.txt
> new file mode 100644
> index 000000000000..6b1c6aad2962
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/phy/qcom,usb-hsic-phy.txt
> @@ -0,0 +1,60 @@
> +Qualcomm's USB HSIC PHY
> +
> +PROPERTIES
> +
> +- compatible:
> + Usage: required
> + Value type: <string>
> + Definition: Should contain "qcom,usb-hsic-phy"
> +
> +- #phy-cells:
> + Usage: required
> + Value type: <u32>
> + Definition: Should contain 0
> +
> +- clocks:
> + Usage: required
> + Value type: <prop-encoded-array>
> + Definition: Should contain clock specifier for phy, calibration and
> + optionally a calibration sleep clock
> +
> +- clock-names:
> + Usage: required
> + Value type: <stringlist>
> + Definition: Should contain "phy, "cal" and optionally "cal_sleep"
> +

[...]

> +
> +static int qcom_usb_hsic_phy_power_on(struct phy *phy)
> +{
> + struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
> + struct ulpi *ulpi = uphy->ulpi;
> + struct pinctrl_state *pins_default;
> + int ret;
> +
> + ret = clk_prepare_enable(uphy->phy_clk);
> + if (ret)
> + return ret;
> +
> + ret = clk_prepare_enable(uphy->cal_clk);
> + if (ret)
> + goto err_cal;
> +
> + ret = clk_prepare_enable(uphy->cal_sleep_clk);
> + if (ret)
> + goto err_sleep;
> +

[...]

> +
> + return ret;
> +err_ulpi:
> + clk_disable_unprepare(uphy->cal_sleep_clk);
> +err_sleep:
> + clk_disable_unprepare(uphy->cal_clk);
> +err_cal:
> + clk_disable_unprepare(uphy->phy_clk);
> + return ret;
> +}
> +
> +static int qcom_usb_hsic_phy_power_off(struct phy *phy)
> +{
> + struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
> +
> + clk_disable_unprepare(uphy->cal_sleep_clk);
> + clk_disable_unprepare(uphy->cal_clk);
> + clk_disable_unprepare(uphy->phy_clk);

[...]

> +static int qcom_usb_hsic_phy_probe(struct ulpi *ulpi)
> +{
> + struct qcom_usb_hsic_phy *uphy;
> + struct phy_provider *p;
> + struct clk *clk;
> +
> + uphy = devm_kzalloc(&ulpi->dev, sizeof(*uphy), GFP_KERNEL);
> + if (!uphy)
> + return -ENOMEM;
> + ulpi_set_drvdata(ulpi, uphy);
> +
> + uphy->ulpi = ulpi;
> + uphy->pctl = devm_pinctrl_get(&ulpi->dev);
> + if (IS_ERR(uphy->pctl))
> + return PTR_ERR(uphy->pctl);
> +
> + uphy->phy_clk = clk = devm_clk_get(&ulpi->dev, "phy");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> +
> + uphy->cal_clk = clk = devm_clk_get(&ulpi->dev, "cal");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> +
> + uphy->cal_sleep_clk = clk = devm_clk_get(&ulpi->dev, "cal_sleep");
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);

Hi Stephen,

In the bindings the cal_sleep is marked optional, and I think should be since AFAIK
it's not present on MDM9615 for example.

Also MDM9615 HSIC requires "core", "alt-core", "phy", "cal" and "iface" clocks.
I assume "core" can be attributed to the main chipidea node, but I think "alt-core" and "iface" should be also optionnal.

Finally, it misses an optional reset line AFAIK mandatory on MDM9615.

Neil

> +
> + uphy->phy = devm_phy_create(&ulpi->dev, ulpi->dev.of_node,
> + &qcom_usb_hsic_phy_ops);
> + if (IS_ERR(uphy->phy))
> + return PTR_ERR(uphy->phy);
> + phy_set_drvdata(uphy->phy, uphy);
> +
> + p = devm_of_phy_provider_register(&ulpi->dev, of_phy_simple_xlate);
> + return PTR_ERR_OR_ZERO(p);
> +}
> +
> +
> +static const struct of_device_id qcom_usb_hsic_phy_match[] = {
> + { .compatible = "qcom,usb-hsic-phy", },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, qcom_usb_hsic_phy_match);
> +
> +static struct ulpi_driver qcom_usb_hsic_phy_driver = {
> + .probe = qcom_usb_hsic_phy_probe,
> + .driver = {
> + .name = "qcom_usb_hsic_phy",
> + .of_match_table = qcom_usb_hsic_phy_match
> + },
> +};
> +module_ulpi_driver(qcom_usb_hsic_phy_driver);
> +
> +MODULE_DESCRIPTION("Qualcomm USB HSIC phy");
> +MODULE_LICENSE("GPL v2");
>