From 238f65aeeae8329fd6f6c2a9b87f2972b96094e5 Mon Sep 17 00:00:00 2001 From: Artur Petrosyan Date: Fri, 16 Apr 2021 16:47:30 +0400 Subject: [PATCH] usb: dwc2: Clear fifo_map when resetting core. Switching from device mode to host mode by disconnecting device cable core enters and exits form hibernation. However, the fifo map remains not cleared. It results to a WARNING (WARNING: CPU: 5 PID: 0 at drivers/usb/dwc2/ gadget.c:307 dwc2_hsotg_init_fifo+0x12/0x152 [dwc2]) if in host mode we disconnect the micro a to b host cable. Because core reset occurs. To avoid the WARNING, fifo_map should be cleared in dwc2_core_reset() function by taking into account configs. fifo_map must be cleared only if driver is configured in "CONFIG_USB_DWC2_PERIPHERAL" or "CONFIG_USB_DWC2_DUAL_ROLE" mode. - Added "static inline void dwc2_clear_fifo_map()" helper function to clear fifo_map with peripheral or dual role mode. - Added a dummy version of "dwc2_clear_fifo_map()" helper for host-only mode. Acked-by: Minas Harutyunyan Signed-off-by: Artur Petrosyan Link: https://lore.kernel.org/r/20210416124731.C500AA005D@mailhost.synopsys.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc2/core.c | 16 ++++++++++++++++ drivers/usb/dwc2/core.h | 3 +++ 2 files changed, 19 insertions(+) diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c index cb65f7f60573..eccd96fa164e 100644 --- a/drivers/usb/dwc2/core.c +++ b/drivers/usb/dwc2/core.c @@ -470,6 +470,22 @@ int dwc2_core_reset(struct dwc2_hsotg *hsotg, bool skip_wait) dwc2_writel(hsotg, greset, GRSTCTL); } + /* + * Switching from device mode to host mode by disconnecting + * device cable core enters and exits form hibernation. + * However, the fifo map remains not cleared. It results + * to a WARNING (WARNING: CPU: 5 PID: 0 at drivers/usb/dwc2/ + * gadget.c:307 dwc2_hsotg_init_fifo+0x12/0x152 [dwc2]) + * if in host mode we disconnect the micro a to b host + * cable. Because core reset occurs. + * To avoid the WARNING, fifo_map should be cleared + * in dwc2_core_reset() function by taking into account configs. + * fifo_map must be cleared only if driver is configured in + * "CONFIG_USB_DWC2_PERIPHERAL" or "CONFIG_USB_DWC2_DUAL_ROLE" + * mode. + */ + dwc2_clear_fifo_map(hsotg); + /* Wait for AHB master IDLE state */ if (dwc2_hsotg_wait_bit_set(hsotg, GRSTCTL, GRSTCTL_AHBIDLE, 10000)) { dev_warn(hsotg->dev, "%s: HANG! AHB Idle timeout GRSTCTL GRSTCTL_AHBIDLE\n", diff --git a/drivers/usb/dwc2/core.h b/drivers/usb/dwc2/core.h index e9277010ba0d..da5ac4a4595b 100644 --- a/drivers/usb/dwc2/core.h +++ b/drivers/usb/dwc2/core.h @@ -1425,6 +1425,8 @@ int dwc2_hsotg_tx_fifo_total_depth(struct dwc2_hsotg *hsotg); int dwc2_hsotg_tx_fifo_average_depth(struct dwc2_hsotg *hsotg); void dwc2_gadget_init_lpm(struct dwc2_hsotg *hsotg); void dwc2_gadget_program_ref_clk(struct dwc2_hsotg *hsotg); +static inline void dwc2_clear_fifo_map(struct dwc2_hsotg *hsotg) +{ hsotg->fifo_map = 0; } #else static inline int dwc2_hsotg_remove(struct dwc2_hsotg *dwc2) { return 0; } @@ -1469,6 +1471,7 @@ static inline int dwc2_hsotg_tx_fifo_average_depth(struct dwc2_hsotg *hsotg) { return 0; } static inline void dwc2_gadget_init_lpm(struct dwc2_hsotg *hsotg) {} static inline void dwc2_gadget_program_ref_clk(struct dwc2_hsotg *hsotg) {} +static inline void dwc2_clear_fifo_map(struct dwc2_hsotg *hsotg) {} #endif #if IS_ENABLED(CONFIG_USB_DWC2_HOST) || IS_ENABLED(CONFIG_USB_DWC2_DUAL_ROLE)