[Patch v9 3/3] phy: Add Qualcomm DWC3 HS/SS PHY driver

Jack Pham jackp at codeaurora.org
Tue Sep 16 11:27:52 PDT 2014


Hi Andy,

On Fri, Sep 12, 2014 at 02:28:08PM -0500, Andy Gross wrote:
> +static int qcom_dwc3_hs_phy_init(struct qcom_dwc3_usb_phy *phy_dwc3)
> +{
> +	u32 val;
> +
> +	/*
> +	 * HSPHY Initialization: Enable UTMI clock, select 19.2MHz fsel
> +	 * enable clamping, and disable RETENTION (power-on default is ENABLED)
> +	 */
> +	val = HSUSB_CTRL_DPSEHV_CLAMP | HSUSB_CTRL_DMSEHV_CLAMP |
> +		HSUSB_CTRL_RETENABLEN  | HSUSB_CTRL_COMMONONN |
> +		HSUSB_CTRL_OTGSESSVLD_CLAMP | HSUSB_CTRL_ID_HV_CLAMP |
> +		HSUSB_CTRL_DPSEHV_CLAMP | HSUSB_CTRL_UTMI_OTG_VBUS_VALID |
> +		HSUSB_CTRL_UTMI_CLK_EN | HSUSB_CTRL_CLAMP_EN | 0x70;
> +
> +	/* use core clock if external reference is not present */
> +	if (!phy_dwc3->xo_clk)
> +		val |= HSUSB_CTRL_USE_CLKCORE;
> +
> +	writel(val, phy_dwc3->base + HSUSB_PHY_CTRL_REG);
> +	usleep_range(2000, 2200);
> +
> +	/* Disable (bypass) VBUS and ID filters */
> +	writel(HSUSB_GCFG_XHCI_REV, phy_dwc3->base + QSCRATCH_GENERAL_CFG);

Is this comment accurate? I believe this bit forces the IP to behave in
XHCI rev 1.0. In which case, shouldn't it be done in the glue driver?

Jack
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