Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
usb: dwc3: Always deassert xilinx resets
If we don't have a usb3 phy we don't need to assert the core resets.
Deassert them even if we didn't assert them to support booting when the
bootloader never released the core from reset.
Signed-off-by: Sean Anderson <sean.anderson@linux.dev>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://patch.msgid.link/20260106171018.501612-1-sean.anderson@linux.dev
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
authored by
Sean Anderson
and committed by
Greg Kroah-Hartman
ec06c803
7a7930c0
+32
-35
+32
-35
drivers/usb/dwc3/dwc3-xilinx.c
+32
-35
drivers/usb/dwc3/dwc3-xilinx.c
···
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goto err;
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}
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-
/*
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* The following core resets are not required unless a USB3 PHY
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* is used, and the subsequent register settings are not required
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* unless a core reset is performed (they should be set properly
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* by the first-stage boot loader, but may be reverted by a core
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* reset). They may also break the configuration if USB3 is actually
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* in use but the usb3-phy entry is missing from the device tree.
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* Therefore, skip these operations in this case.
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*/
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if (!priv_data->usb3_phy) {
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/* Deselect the PIPE Clock Select bit in FPD PIPE Clock register */
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writel(PIPE_CLK_DESELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
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goto skip_usb3_phy;
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-
}
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-
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crst = devm_reset_control_get_exclusive(dev, "usb_crst");
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if (IS_ERR(crst)) {
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ret = PTR_ERR(crst);
···
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goto err;
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}
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ret = reset_control_assert(crst);
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if (ret < 0) {
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dev_err(dev, "Failed to assert core reset\n");
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goto err;
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}
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+
/*
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* Asserting the core resets is not required unless a USB3 PHY is used.
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* They may also break the configuration if USB3 is actually in use but
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* the usb3-phy entry is missing from the device tree. Therefore, skip
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* a full reset cycle and just deassert the resets if the phy is
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* absent.
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*/
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if (priv_data->usb3_phy) {
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ret = reset_control_assert(crst);
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if (ret < 0) {
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dev_err(dev, "Failed to assert core reset\n");
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goto err;
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}
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-
ret = reset_control_assert(hibrst);
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if (ret < 0) {
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dev_err(dev, "Failed to assert hibernation reset\n");
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goto err;
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}
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+
ret = reset_control_assert(hibrst);
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if (ret < 0) {
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dev_err(dev, "Failed to assert hibernation reset\n");
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goto err;
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}
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-
ret = reset_control_assert(apbrst);
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if (ret < 0) {
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dev_err(dev, "Failed to assert APB reset\n");
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goto err;
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ret = reset_control_assert(apbrst);
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if (ret < 0) {
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dev_err(dev, "Failed to assert APB reset\n");
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goto err;
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}
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}
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ret = phy_init(priv_data->usb3_phy);
···
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goto err;
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}
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-
/* Set PIPE Power Present signal in FPD Power Present Register*/
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writel(FPD_POWER_PRSNT_OPTION, priv_data->regs + XLNX_USB_FPD_POWER_PRSNT);
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-
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/* Set the PIPE Clock Select bit in FPD PIPE Clock register */
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writel(PIPE_CLK_SELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
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+
if (priv_data->usb3_phy) {
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/* Set PIPE Power Present signal in FPD Power Present Register*/
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writel(FPD_POWER_PRSNT_OPTION, priv_data->regs + XLNX_USB_FPD_POWER_PRSNT);
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/* Set the PIPE Clock Select bit in FPD PIPE Clock register */
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writel(PIPE_CLK_SELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
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} else {
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/* Deselect the PIPE Clock Select bit in FPD PIPE Clock register */
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writel(PIPE_CLK_DESELECT, priv_data->regs + XLNX_USB_FPD_PIPE_CLK);
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+
}
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ret = reset_control_deassert(crst);
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if (ret < 0) {
···
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goto err;
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}
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-
skip_usb3_phy:
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/* ulpi reset via gpio-modepin or gpio-framework driver */
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reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
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if (IS_ERR(reset_gpio)) {