Commit 0759956f authored by Felipe Balbi's avatar Felipe Balbi
Browse files

usb: dwc3: core: introduce dwc3_core_is_valid() 



This little helper will be used to make sure we're
dealing with a valid Synopsys DWC3 or DWC3.1 core.

Signed-off-by: default avatarFelipe Balbi <felipe.balbi@linux.intel.com>
parent 0bb39ca1

drivers/usb/dwc3/core.c

+22 −10
Original line number Diff line number Diff line
@@ -594,19 +594,12 @@ static void dwc3_core_exit(struct dwc3 *dwc) 
	phy_power_off(dwc->usb3_generic_phy);

}



/**

 * dwc3_core_init - Low-level initialization of DWC3 Core

 * @dwc: Pointer to our controller context structure

 *

 * Returns 0 on success otherwise negative errno.

 */

static int dwc3_core_init(struct dwc3 *dwc)

static bool dwc3_core_is_valid(struct dwc3 *dwc)

{

	u32			hwparams4 = dwc->hwparams.hwparams4;

	u32 reg;

	int			ret;



	reg = dwc3_readl(dwc->regs, DWC3_GSNPSID);



	/* This should read as U3 followed by revision number */

	if ((reg & DWC3_GSNPSID_MASK) == 0x55330000) {

		/* Detected DWC_usb3 IP */
@@ -616,6 +609,25 @@ static int dwc3_core_init(struct dwc3 *dwc) 
		dwc->revision = dwc3_readl(dwc->regs, DWC3_VER_NUMBER);

		dwc->revision |= DWC3_REVISION_IS_DWC31;

	} else {

		return false;

	}



	return true;

}



/**

 * dwc3_core_init - Low-level initialization of DWC3 Core

 * @dwc: Pointer to our controller context structure

 *

 * Returns 0 on success otherwise negative errno.

 */

static int dwc3_core_init(struct dwc3 *dwc)

{

	u32			hwparams4 = dwc->hwparams.hwparams4;

	u32			reg;

	int			ret;



	if (!dwc3_core_is_valid(dwc)) {

		dev_err(dwc->dev, "this is not a DesignWare USB3 DRD Core\n");

		ret = -ENODEV;

		goto err0;