We initiate dwc2 usb controller in BIOS, dwc2_core_reset() should be called before dwc2_get_hwparams() to reset core registers to default value. Without this the FIFO setting might be incorrect because calculating FIFO size need power-on value of GRXFSIZ/GNPTXFSIZ/HPTXFSIZ registers. This patch could avoid warnning massage like in rk3288 platform: [ 2.074764] dwc2 ff580000.usb: 256 invalid for host_perio_tx_fifo_size. Check HW configuration. Signed-off-by: Yunzhi Li <lyz@xxxxxxxxxxxxxx> --- drivers/usb/dwc2/core.c | 2 +- drivers/usb/dwc2/core.h | 1 + drivers/usb/dwc2/platform.c | 21 ++++++++++++++++++++- 3 files changed, 22 insertions(+), 2 deletions(-) diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c index c3cc1a7..86d1d65 100644 --- a/drivers/usb/dwc2/core.c +++ b/drivers/usb/dwc2/core.c @@ -474,7 +474,7 @@ static void dwc2_init_fs_ls_pclk_sel(struct dwc2_hsotg *hsotg) * Do core a soft reset of the core. Be careful with this because it * resets all the internal state machines of the core. */ -static int dwc2_core_reset(struct dwc2_hsotg *hsotg) +int dwc2_core_reset(struct dwc2_hsotg *hsotg) { u32 greset; int count = 0; diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index 0ed87620..5d95aec 100644 --- a/drivers/usb/dwc2/core.h +++ b/drivers/usb/dwc2/core.h @@ -846,6 +846,7 @@ enum dwc2_halt_status { * The following functions support initialization of the core driver component * and the DWC_otg controller */ +extern int dwc2_core_reset(struct dwc2_hsotg *hsotg); extern void dwc2_core_host_init(struct dwc2_hsotg *hsotg); extern int dwc2_enter_hibernation(struct dwc2_hsotg *hsotg); extern int dwc2_exit_hibernation(struct dwc2_hsotg *hsotg, bool restore); diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c index 9093530..55d378a 100644 --- a/drivers/usb/dwc2/platform.c +++ b/drivers/usb/dwc2/platform.c @@ -166,7 +166,8 @@ static int dwc2_driver_probe(struct platform_device *dev) struct phy *phy; struct usb_phy *uphy; int retval; - int irq; + int irq, count = 0; + u32 greset; match = of_match_device(dwc2_of_match_table, &dev->dev); if (match && match->data) { @@ -243,6 +244,24 @@ static int dwc2_driver_probe(struct platform_device *dev) spin_lock_init(&hsotg->lock); mutex_init(&hsotg->init_mutex); + /* + * Reset before dwc2_get_hwparams() then it could get power-on real + * reset value form registers. + */ + count = 0; + greset |= GRSTCTL_CSFTRST; + writel(greset, hsotg->regs + GRSTCTL); + do { + usleep_range(20000, 40000); + greset = readl(hsotg->regs + GRSTCTL); + if (++count > 50) { + dev_warn(hsotg->dev, + "%s() HANG! Soft Reset GRSTCTL=%0x\n", + __func__, greset); + return -EBUSY; + } + } while (greset & GRSTCTL_CSFTRST); + /* Detect config values from hardware */ retval = dwc2_get_hwparams(hsotg); if (retval) -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html