Re: [PATCH 2/3] usb: dwc3: exynos: Use Exynos specific XHCI-plat driver variant

[Anand Moon <linux.amoon@gmail.com>]

Hi Marek,

On Thu, 27 Jun 2019 at 12:47, Marek Szyprowski <m.szyprowski@samsung.com> wrote:
>
> Exynos5 SoCs needs to calibrate USB3.0 DRD PHY after every XHCI HCD
> reset. This patch adds support for instantiating Exynos5-specific variant
> of XHCI-plat driver, which handles the required USB3.0 DRD PHY
> calibration.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---

Please add my tested on XU4 / XU3 using linux next-20190716
Tested-by: Anand Moon <linux.amoon@gmail.com>

Best Regards
-Anand

>  drivers/usb/dwc3/Kconfig       |  1 +
>  drivers/usb/dwc3/core.c        |  1 +
>  drivers/usb/dwc3/core.h        |  1 +
>  drivers/usb/dwc3/dwc3-exynos.c | 64 +++++++++++++++++++++++-----------
>  drivers/usb/dwc3/host.c        |  2 +-
>  5 files changed, 47 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/usb/dwc3/Kconfig b/drivers/usb/dwc3/Kconfig
> index 89abc6078703..badf86dfb027 100644
> --- a/drivers/usb/dwc3/Kconfig
> +++ b/drivers/usb/dwc3/Kconfig
> @@ -67,6 +67,7 @@ config USB_DWC3_OMAP
>  config USB_DWC3_EXYNOS
>         tristate "Samsung Exynos Platform"
>         depends on (ARCH_EXYNOS || COMPILE_TEST) && OF
> +       select USB_XHCI_EXYNOS if USB_XHCI_PLATFORM
>         default USB_DWC3
>         help
>           Recent Exynos5 SoCs ship with one DesignWare Core USB3 IP inside,
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index c9bb93a2c81e..baa029ceede9 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1303,6 +1303,7 @@ static void dwc3_get_properties(struct dwc3 *dwc)
>                                     &dwc->hsphy_interface);
>         device_property_read_u32(dev, "snps,quirk-frame-length-adjustment",
>                                  &dwc->fladj);
> +       device_property_read_string(dev, "snps,xhci_variant", &dwc->hcd_name);
>
>         dwc->dis_metastability_quirk = device_property_read_bool(dev,
>                                 "snps,dis_metastability_quirk");
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 3dd783b889cb..1b8f5f5814a4 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1176,6 +1176,7 @@ struct dwc3 {
>         u8                      tx_max_burst_prd;
>
>         const char              *hsphy_interface;
> +       const char              *hcd_name;
>
>         unsigned                connected:1;
>         unsigned                delayed_status:1;
> diff --git a/drivers/usb/dwc3/dwc3-exynos.c b/drivers/usb/dwc3/dwc3-exynos.c
> index c1e9ea621f41..4e847073e85e 100644
> --- a/drivers/usb/dwc3/dwc3-exynos.c
> +++ b/drivers/usb/dwc3/dwc3-exynos.c
> @@ -13,6 +13,7 @@
>  #include <linux/slab.h>
>  #include <linux/platform_device.h>
>  #include <linux/clk.h>
> +#include <linux/dma-mapping.h>
>  #include <linux/of.h>
>  #include <linux/of_platform.h>
>  #include <linux/regulator/consumer.h>
> @@ -35,22 +36,20 @@ struct dwc3_exynos {
>
>         struct regulator        *vdd33;
>         struct regulator        *vdd10;
> +       struct platform_device  *dwc3;
>  };
>
> -static int dwc3_exynos_remove_child(struct device *dev, void *unused)
> -{
> -       struct platform_device *pdev = to_platform_device(dev);
> -
> -       platform_device_unregister(pdev);
> -
> -       return 0;
> -}
> +static const struct property_entry dwc3_exynos_properties[] = {
> +       PROPERTY_ENTRY_STRING("snps,xhci_variant", "exynos5-dwc3-xhci"),
> +       {}
> +};
>
>  static int dwc3_exynos_probe(struct platform_device *pdev)
>  {
>         struct dwc3_exynos      *exynos;
>         struct device           *dev = &pdev->dev;
> -       struct device_node      *node = dev->of_node;
> +       struct device_node      *node = dev->of_node, *child;
> +       struct platform_device  *dwc3;
>         const struct dwc3_exynos_driverdata *driver_data;
>         int                     i, ret;
>
> @@ -109,21 +108,43 @@ static int dwc3_exynos_probe(struct platform_device *pdev)
>                 goto vdd10_err;
>         }
>
> -       if (node) {
> -               ret = of_platform_populate(node, NULL, NULL, dev);
> -               if (ret) {
> -                       dev_err(dev, "failed to add dwc3 core\n");
> -                       goto populate_err;
> -               }
> -       } else {
> -               dev_err(dev, "no device node, failed to add dwc3 core\n");
> -               ret = -ENODEV;
> -               goto populate_err;
> +       child = of_get_next_child(node, NULL);
> +       if (!child) {
> +               dev_err(dev, "Failed to find DWC3 core device node\n");
> +               goto dwc3_child_err;
> +       }
> +
> +       dwc3 = of_device_alloc(child, NULL, dev);
> +       if (!dwc3) {
> +               dev_err(dev, "Failed to allocate DWC3 core device\n");
> +               goto dwc3_alloc_err;
> +       }
> +
> +       dwc3->dev.coherent_dma_mask = DMA_BIT_MASK(32);
> +       dwc3->dev.dma_mask = &dwc3->dev.coherent_dma_mask;
> +       dwc3->dev.bus = &platform_bus_type;
> +
> +       ret = platform_device_add_properties(dwc3, dwc3_exynos_properties);
> +       if (ret < 0) {
> +               dev_err(dev, "Failed to add properties to DWC3 device\n");
> +               goto dwc3_props_err;
> +       }
> +
> +       ret = of_device_add(dwc3);
> +       if (ret) {
> +               dev_err(&pdev->dev, "Failed to register DWC3 core device\n");
> +               goto dwc3_props_err;
>         }
> +       exynos->dwc3 = dwc3;
> +       of_node_put(child);
>
>         return 0;
>
> -populate_err:
> +dwc3_props_err:
> +       platform_device_put(dwc3);
> +dwc3_alloc_err:
> +       of_node_put(child);
> +dwc3_child_err:
>         regulator_disable(exynos->vdd10);
>  vdd10_err:
>         regulator_disable(exynos->vdd33);
> @@ -142,7 +163,8 @@ static int dwc3_exynos_remove(struct platform_device *pdev)
>         struct dwc3_exynos      *exynos = platform_get_drvdata(pdev);
>         int i;
>
> -       device_for_each_child(&pdev->dev, NULL, dwc3_exynos_remove_child);
> +       of_device_unregister(exynos->dwc3);
> +       platform_device_put(exynos->dwc3);
>
>         for (i = exynos->num_clks - 1; i >= 0; i--)
>                 clk_disable_unprepare(exynos->clks[i]);
> diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
> index f55947294f7c..b526d0c78c3b 100644
> --- a/drivers/usb/dwc3/host.c
> +++ b/drivers/usb/dwc3/host.c
> @@ -71,7 +71,7 @@ int dwc3_host_init(struct dwc3 *dwc)
>         dwc->xhci_resources[1].flags = res->flags;
>         dwc->xhci_resources[1].name = res->name;
>
> -       xhci = platform_device_alloc("xhci-hcd", PLATFORM_DEVID_AUTO);
> +       xhci = platform_device_alloc(dwc->hcd_name, PLATFORM_DEVID_AUTO);
>         if (!xhci) {
>                 dev_err(dwc->dev, "couldn't allocate xHCI device\n");
>                 return -ENOMEM;
> --
> 2.17.1
>