[PATCH v3 1/1] phy: starfive: jh7110-usb: Fix link configuration to controller

[Emil Renner Berthing]

Minda Chen wrote:
> From: Jan Kiszka <jan.kiszka at siemens.com>
>
> In order to connect the USB 2.0 PHY to its controller, we also need to
> set "u0_pdrstn_split_sw_usbpipe_plugen" [1]. Some downstream U-Boot
> versions did that, but upstream firmware does not, and the kernel must
> not rely on such behavior anyway. Failing to set this left the USB
> gadget port invisible to connected hosts behind.
>
> Link: https://doc-en.rvspace.org/JH7110/TRM/JH7110_TRM/sys_syscon.html#sys_syscon__section_b3l_fqs_wsb [1]
> Fixes: 16d3a71c20cf ("phy: starfive: Add JH7110 USB 2.0 PHY driver")
> Signed-off-by: Jan Kiszka <jan.kiszka at siemens.com>
> Signed-off-by: Minda Chen <minda.chen at starfivetech.com>

Apologies if this was already applied somewhere, but I don't see message that
it was. In any case this looks good to me, thanks.

Reviewed-by: Emil Renner Berthing <emil.renner.berthing at canonical.com>

> ---
>  drivers/phy/starfive/phy-jh7110-usb.c | 16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
>
> diff --git a/drivers/phy/starfive/phy-jh7110-usb.c b/drivers/phy/starfive/phy-jh7110-usb.c
> index 633912f8a05d..dabe59953070 100644
> --- a/drivers/phy/starfive/phy-jh7110-usb.c
> +++ b/drivers/phy/starfive/phy-jh7110-usb.c
> @@ -10,18 +10,24 @@
>  #include <linux/clk.h>
>  #include <linux/err.h>
>  #include <linux/io.h>
> +#include <linux/mfd/syscon.h>
>  #include <linux/module.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
> +#include <linux/regmap.h>
>  #include <linux/usb/of.h>
>
>  #define USB_125M_CLK_RATE		125000000
>  #define USB_LS_KEEPALIVE_OFF		0x4
>  #define USB_LS_KEEPALIVE_ENABLE		BIT(4)
>
> +#define USB_PDRSTN_SPLIT		BIT(17)
> +#define SYSCON_USB_SPLIT_OFFSET		0x18
> +
>  struct jh7110_usb2_phy {
>  	struct phy *phy;
>  	void __iomem *regs;
> +	struct regmap *sys_syscon;
>  	struct clk *usb_125m_clk;
>  	struct clk *app_125m;
>  	enum phy_mode mode;
> @@ -61,6 +67,10 @@ static int usb2_phy_set_mode(struct phy *_phy,
>  		usb2_set_ls_keepalive(phy, (mode != PHY_MODE_USB_DEVICE));
>  	}
>
> +	/* Connect usb 2.0 phy mode */
> +	regmap_update_bits(phy->sys_syscon, SYSCON_USB_SPLIT_OFFSET,
> +			   USB_PDRSTN_SPLIT, USB_PDRSTN_SPLIT);
> +
>  	return 0;
>  }
>
> @@ -129,6 +139,12 @@ static int jh7110_usb_phy_probe(struct platform_device *pdev)
>  	phy_set_drvdata(phy->phy, phy);
>  	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
>
> +	phy->sys_syscon =
> +		syscon_regmap_lookup_by_compatible("starfive,jh7110-sys-syscon");
> +	if (IS_ERR(phy->sys_syscon))
> +		return dev_err_probe(dev, PTR_ERR(phy->sys_syscon),
> +			"Failed to get sys-syscon\n");
> +
>  	return PTR_ERR_OR_ZERO(phy_provider);
>  }
>
> --
> 2.17.1
>