[PATCH v7 4/9] usb: dwc3: core: Skip setting event buffers for host only controllers

From: Krishna Kurapati
Date: Mon May 01 2023 - 10:35:52 EST


On some SoC's like SA8295P where the tertiary controller is host-only
capable, GEVTADDRHI/LO, GEVTSIZ, GEVTCOUNT registers are not accessible.
Trying to setup them up during core_init leads to a crash.

For DRD/Peripheral supported controllers, event buffer setup is done
again in gadget_pullup. Skip setup or cleanup of event buffers if
controller is host-only capable.

Signed-off-by: Krishna Kurapati <quic_kriskura@xxxxxxxxxxx>
---
drivers/usb/dwc3/core.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index b8ac7bcee391..8625fc5c7ab4 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -835,7 +835,12 @@ static void dwc3_clk_disable(struct dwc3 *dwc)

static void dwc3_core_exit(struct dwc3 *dwc)
{
- dwc3_event_buffers_cleanup(dwc);
+ unsigned int hw_mode;
+
+ hw_mode = DWC3_GHWPARAMS0_MODE(dwc->hwparams.hwparams0);
+ if (hw_mode != DWC3_GHWPARAMS0_MODE_HOST)
+ dwc3_event_buffers_cleanup(dwc);
+
dwc3_phy_power_off(dwc);
dwc3_phy_exit(dwc);
dwc3_clk_disable(dwc);
@@ -1141,10 +1146,12 @@ static int dwc3_core_init(struct dwc3 *dwc)
if (ret)
goto err_exit_phy;

- ret = dwc3_event_buffers_setup(dwc);
- if (ret) {
- dev_err(dwc->dev, "failed to setup event buffers\n");
- goto err_power_off_phy;
+ if (hw_mode != DWC3_GHWPARAMS0_MODE_HOST) {
+ ret = dwc3_event_buffers_setup(dwc);
+ if (ret) {
+ dev_err(dwc->dev, "failed to setup event buffers\n");
+ goto err_power_off_phy;
+ }
}

/*
@@ -1958,7 +1965,10 @@ static int dwc3_probe(struct platform_device *pdev)

err_exit_debugfs:
dwc3_debugfs_exit(dwc);
- dwc3_event_buffers_cleanup(dwc);
+
+ if (hw_mode != DWC3_GHWPARAMS0_MODE_HOST)
+ dwc3_event_buffers_cleanup(dwc);
+
dwc3_phy_power_off(dwc);
dwc3_phy_exit(dwc);
dwc3_ulpi_exit(dwc);
--
2.40.0