[v6,1/3] phy: add driver for Qualcomm IPQ40xx USB PHY

From: John Crispin <john@phrozen.org>

Add a driver to setup the USB phy on Qualcom Dakota SoCs.
The driver sets up HS and SS phys.

Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Cc: Luka Perkov <luka.perkov@sartura.hr>
---
Changes from v2 to v3:
* Remove magic writes as they are not needed
* Correct commit message

 drivers/phy/qualcomm/Kconfig                |   7 +
 drivers/phy/qualcomm/Makefile               |   1 +
 drivers/phy/qualcomm/phy-qcom-ipq4019-usb.c | 152 ++++++++++++++++++++
 3 files changed, 160 insertions(+)
 create mode 100644 drivers/phy/qualcomm/phy-qcom-ipq4019-usb.c

On Wed, Apr 01, 2020 at 06:35:43PM +0200, Robert Marko wrote:
> This patch adds the binding documentation for the HS/SS USB PHY found
> inside Qualcom Dakota SoCs.
> 
> Signed-off-by: John Crispin <john@phrozen.org>
> Signed-off-by: Robert Marko <robert.marko@sartura.hr>
> Cc: Luka Perkov <luka.perkov@sartura.hr>
> ---
> Changes from v5 to v6:
> * Add missing include for reset defines in example
> * Fix warning for missing # in #phy-cells
> 
> Changes from v4 to v5:
> * Replace tabs with whitespaces
> * Add maintainer property
> 
>  .../bindings/phy/qcom-usb-ipq4019-phy.yaml    | 50 +++++++++++++++++++
>  1 file changed, 50 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/phy/qcom-usb-ipq4019-phy.yaml

Reviewed-by: Rob Herring <robh@kernel.org>

Kishon, can you pick this up for 5.8?

Thanks

On Wed, Apr 1, 2020 at 6:36 PM Robert Marko <robert.marko@sartura.hr> wrote:
>
> From: John Crispin <john@phrozen.org>
>
> Add a driver to setup the USB phy on Qualcom Dakota SoCs.
> The driver sets up HS and SS phys.
>
> Signed-off-by: John Crispin <john@phrozen.org>
> Signed-off-by: Robert Marko <robert.marko@sartura.hr>
> Cc: Luka Perkov <luka.perkov@sartura.hr>
> ---
> Changes from v2 to v3:
> * Remove magic writes as they are not needed
> * Correct commit message
>
>  drivers/phy/qualcomm/Kconfig                |   7 +
>  drivers/phy/qualcomm/Makefile               |   1 +
>  drivers/phy/qualcomm/phy-qcom-ipq4019-usb.c | 152 ++++++++++++++++++++
>  3 files changed, 160 insertions(+)
>  create mode 100644 drivers/phy/qualcomm/phy-qcom-ipq4019-usb.c
>
> diff --git a/drivers/phy/qualcomm/Kconfig b/drivers/phy/qualcomm/Kconfig
> index e46824da29f6..964bd5d784d2 100644
> --- a/drivers/phy/qualcomm/Kconfig
> +++ b/drivers/phy/qualcomm/Kconfig
> @@ -18,6 +18,13 @@ config PHY_QCOM_APQ8064_SATA
>         depends on OF
>         select GENERIC_PHY
>
> +config PHY_QCOM_IPQ4019_USB
> +       tristate "Qualcomm IPQ4019 USB PHY module"
> +       depends on OF && ARCH_QCOM
> +       select GENERIC_PHY
> +       help
> +         Support for the USB PHY on QCOM IPQ4019/Dakota chipsets.
> +
>  config PHY_QCOM_IPQ806X_SATA
>         tristate "Qualcomm IPQ806x SATA SerDes/PHY driver"
>         depends on ARCH_QCOM
> diff --git a/drivers/phy/qualcomm/Makefile b/drivers/phy/qualcomm/Makefile
> index 283251d6a5d9..8afe6c4f5178 100644
> --- a/drivers/phy/qualcomm/Makefile
> +++ b/drivers/phy/qualcomm/Makefile
> @@ -1,6 +1,7 @@
>  # SPDX-License-Identifier: GPL-2.0
>  obj-$(CONFIG_PHY_ATH79_USB)            += phy-ath79-usb.o
>  obj-$(CONFIG_PHY_QCOM_APQ8064_SATA)    += phy-qcom-apq8064-sata.o
> +obj-$(CONFIG_PHY_QCOM_IPQ4019_USB)     += phy-qcom-ipq4019-usb.o
>  obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA)    += phy-qcom-ipq806x-sata.o
>  obj-$(CONFIG_PHY_QCOM_PCIE2)           += phy-qcom-pcie2.o
>  obj-$(CONFIG_PHY_QCOM_QMP)             += phy-qcom-qmp.o
> diff --git a/drivers/phy/qualcomm/phy-qcom-ipq4019-usb.c b/drivers/phy/qualcomm/phy-qcom-ipq4019-usb.c
> new file mode 100644
> index 000000000000..7efebae6b6fd
> --- /dev/null
> +++ b/drivers/phy/qualcomm/phy-qcom-ipq4019-usb.c
> @@ -0,0 +1,152 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Copyright (C) 2018 John Crispin <john@phrozen.org>
> + *
> + * Based on code from
> + * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
> + *
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of_platform.h>
> +#include <linux/phy/phy.h>
> +#include <linux/platform_device.h>
> +#include <linux/reset.h>
> +
> +struct ipq4019_usb_phy {
> +       struct device           *dev;
> +       struct phy              *phy;
> +       void __iomem            *base;
> +       struct reset_control    *por_rst;
> +       struct reset_control    *srif_rst;
> +};
> +
> +static int ipq4019_ss_phy_power_off(struct phy *_phy)
> +{
> +       struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
> +
> +       reset_control_assert(phy->por_rst);
> +       msleep(10);
> +
> +       return 0;
> +}
> +
> +static int ipq4019_ss_phy_power_on(struct phy *_phy)
> +{
> +       struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
> +
> +       ipq4019_ss_phy_power_off(_phy);
> +
> +       reset_control_deassert(phy->por_rst);
> +
> +       return 0;
> +}
> +
> +static struct phy_ops ipq4019_usb_ss_phy_ops = {
> +       .power_on       = ipq4019_ss_phy_power_on,
> +       .power_off      = ipq4019_ss_phy_power_off,
> +};
> +
> +static int ipq4019_hs_phy_power_off(struct phy *_phy)
> +{
> +       struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
> +
> +       reset_control_assert(phy->por_rst);
> +       msleep(10);
> +
> +       reset_control_assert(phy->srif_rst);
> +       msleep(10);
> +
> +       return 0;
> +}
> +
> +static int ipq4019_hs_phy_power_on(struct phy *_phy)
> +{
> +       struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
> +
> +       ipq4019_hs_phy_power_off(_phy);
> +
> +       reset_control_deassert(phy->srif_rst);
> +       msleep(10);
> +
> +       reset_control_deassert(phy->por_rst);
> +
> +       return 0;
> +}
> +
> +static struct phy_ops ipq4019_usb_hs_phy_ops = {
> +       .power_on       = ipq4019_hs_phy_power_on,
> +       .power_off      = ipq4019_hs_phy_power_off,
> +};
> +
> +static const struct of_device_id ipq4019_usb_phy_of_match[] = {
> +       { .compatible = "qcom,usb-hs-ipq4019-phy", .data = &ipq4019_usb_hs_phy_ops},
> +       { .compatible = "qcom,usb-ss-ipq4019-phy", .data = &ipq4019_usb_ss_phy_ops},
> +       { },
> +};
> +MODULE_DEVICE_TABLE(of, ipq4019_usb_phy_of_match);
> +
> +static int ipq4019_usb_phy_probe(struct platform_device *pdev)
> +{
> +       struct device *dev = &pdev->dev;
> +       struct resource *res;
> +       struct phy_provider *phy_provider;
> +       struct ipq4019_usb_phy *phy;
> +       const struct of_device_id *match;
> +
> +       match = of_match_device(ipq4019_usb_phy_of_match, &pdev->dev);
> +       if (!match)
> +               return -ENODEV;
> +
> +       phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
> +       if (!phy)
> +               return -ENOMEM;
> +
> +       phy->dev = &pdev->dev;
> +       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       phy->base = devm_ioremap_resource(&pdev->dev, res);
> +       if (IS_ERR(phy->base)) {
> +               dev_err(dev, "failed to remap register memory\n");
> +               return PTR_ERR(phy->base);
> +       }
> +
> +       phy->por_rst = devm_reset_control_get(phy->dev, "por_rst");
> +       if (IS_ERR(phy->por_rst)) {
> +               if (PTR_ERR(phy->por_rst) != -EPROBE_DEFER)
> +                       dev_err(dev, "POR reset is missing\n");
> +               return PTR_ERR(phy->por_rst);
> +       }
> +
> +       phy->srif_rst = devm_reset_control_get_optional(phy->dev, "srif_rst");
> +       if (IS_ERR(phy->srif_rst))
> +               return PTR_ERR(phy->srif_rst);
> +
> +       phy->phy = devm_phy_create(dev, NULL, match->data);
> +       if (IS_ERR(phy->phy)) {
> +               dev_err(dev, "failed to create PHY\n");
> +               return PTR_ERR(phy->phy);
> +       }
> +       phy_set_drvdata(phy->phy, phy);
> +
> +       phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
> +
> +       return PTR_ERR_OR_ZERO(phy_provider);
> +}
> +
> +static struct platform_driver ipq4019_usb_phy_driver = {
> +       .probe  = ipq4019_usb_phy_probe,
> +       .driver = {
> +               .of_match_table = ipq4019_usb_phy_of_match,
> +               .name  = "ipq4019-usb-phy",
> +       }
> +};
> +module_platform_driver(ipq4019_usb_phy_driver);
> +
> +MODULE_DESCRIPTION("QCOM/IPQ4019 USB phy driver");
> +MODULE_AUTHOR("John Crispin <john@phrozen.org>");
> +MODULE_LICENSE("GPL v2");
> --
> 2.26.0
>

Hello Robert,

On 01-04-20, 18:35, Robert Marko wrote:

> +static int ipq4019_ss_phy_power_on(struct phy *_phy)
> +{
> +	struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
> +
> +	ipq4019_ss_phy_power_off(_phy);
> +
> +	reset_control_deassert(phy->por_rst);
> +
> +	return 0;
> +}
> +
> +static struct phy_ops ipq4019_usb_ss_phy_ops = {
> +	.power_on	= ipq4019_ss_phy_power_on,
> +	.power_off	= ipq4019_ss_phy_power_off,
> +};
> +
> +static int ipq4019_hs_phy_power_off(struct phy *_phy)
> +{
> +	struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
> +
> +	reset_control_assert(phy->por_rst);
> +	msleep(10);

why not call ipq4019_ss_phy_power_off() here as well?

> +
> +	reset_control_assert(phy->srif_rst);
> +	msleep(10);
> +
> +	return 0;
> +}
> +
> +static int ipq4019_hs_phy_power_on(struct phy *_phy)
> +{
> +	struct ipq4019_usb_phy *phy = phy_get_drvdata(_phy);
> +
> +	ipq4019_hs_phy_power_off(_phy);
> +
> +	reset_control_deassert(phy->srif_rst);
> +	msleep(10);
> +
> +	reset_control_deassert(phy->por_rst);
> +
> +	return 0;
> +}
> +
> +static struct phy_ops ipq4019_usb_hs_phy_ops = {
> +	.power_on	= ipq4019_hs_phy_power_on,
> +	.power_off	= ipq4019_hs_phy_power_off,
> +};

So this is fiddling with resets, what about phy configuration and
calibration, who take care of that?

> +static int ipq4019_usb_phy_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct resource *res;
> +	struct phy_provider *phy_provider;
> +	struct ipq4019_usb_phy *phy;
> +	const struct of_device_id *match;
> +
> +	match = of_match_device(ipq4019_usb_phy_of_match, &pdev->dev);
> +	if (!match)
> +		return -ENODEV;

you are using this to get match-data few lines below, why not use
of_device_get_match_data() and get the match->data which you are
interested in?