u-boot/drivers/usb/host/ehci-generic.c
Andre Przywara 81755b8c20 usb: host: ehci-generic: Make resets and clocks optional
The generic EHCI binding does not *require* resets and clocks
properties, and indeed for instance the Allwinner A20 SoCs does not
need or define any resets in its DT.

Don't easily give up if clk_get_bulk() or reset_get_bulk() return an
error, but check if that is due to the DT simply having no entries for
either of them.

This fixes USB operation on all boards with an Allwinner A10 or A20 SoC,
which were reporting an error after commit ba96176ab7:
=======================
Bus usb@1c14000: ehci_generic usb@1c14000: Failed to get resets (err=-2)
probe failed, error -2
=======================

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
2022-06-16 15:22:55 -04:00

173 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2015 Alexey Brodkin <abrodkin@synopsys.com>
*/
#include <common.h>
#include <clk.h>
#include <log.h>
#include <dm/device_compat.h>
#include <dm/devres.h>
#include <dm/ofnode.h>
#include <generic-phy.h>
#include <reset.h>
#include <asm/io.h>
#include <dm.h>
#include "ehci.h"
#include <power/regulator.h>
/*
* Even though here we don't explicitly use "struct ehci_ctrl"
* ehci_register() expects it to be the first thing that resides in
* device's private data.
*/
struct generic_ehci {
struct ehci_ctrl ctrl;
struct clk_bulk clocks;
struct reset_ctl_bulk resets;
struct phy phy;
struct udevice *vbus_supply;
};
static int ehci_enable_vbus_supply(struct udevice *dev)
{
struct generic_ehci *priv = dev_get_priv(dev);
int ret;
ret = device_get_supply_regulator(dev, "vbus-supply",
&priv->vbus_supply);
if (ret && ret != -ENOENT)
return ret;
if (priv->vbus_supply) {
ret = regulator_set_enable(priv->vbus_supply, true);
if (ret) {
dev_err(dev, "Error enabling VBUS supply (ret=%d)\n", ret);
return ret;
}
} else {
dev_dbg(dev, "No vbus supply\n");
}
return 0;
}
static int ehci_disable_vbus_supply(struct generic_ehci *priv)
{
if (priv->vbus_supply)
return regulator_set_enable(priv->vbus_supply, false);
else
return 0;
}
static int ehci_usb_probe(struct udevice *dev)
{
struct generic_ehci *priv = dev_get_priv(dev);
struct ehci_hccr *hccr;
struct ehci_hcor *hcor;
int err, ret;
err = 0;
ret = clk_get_bulk(dev, &priv->clocks);
if (ret && ret != -ENOENT) {
dev_err(dev, "Failed to get clocks (ret=%d)\n", ret);
return ret;
}
err = clk_enable_bulk(&priv->clocks);
if (err) {
dev_err(dev, "Failed to enable clocks (err=%d)\n", err);
goto clk_err;
}
err = reset_get_bulk(dev, &priv->resets);
if (ret && ret != -ENOENT) {
dev_err(dev, "Failed to get resets (err=%d)\n", err);
goto clk_err;
}
err = reset_deassert_bulk(&priv->resets);
if (err) {
dev_err(dev, "Failed to get deassert resets (err=%d)\n", err);
goto reset_err;
}
err = ehci_enable_vbus_supply(dev);
if (err)
goto reset_err;
err = ehci_setup_phy(dev, &priv->phy, 0);
if (err)
goto regulator_err;
hccr = map_physmem(dev_read_addr(dev), 0x100, MAP_NOCACHE);
hcor = (struct ehci_hcor *)((uintptr_t)hccr +
HC_LENGTH(ehci_readl(&hccr->cr_capbase)));
err = ehci_register(dev, hccr, hcor, NULL, 0, USB_INIT_HOST);
if (err)
goto phy_err;
return 0;
phy_err:
ret = ehci_shutdown_phy(dev, &priv->phy);
if (ret)
dev_err(dev, "failed to shutdown usb phy (ret=%d)\n", ret);
regulator_err:
ret = ehci_disable_vbus_supply(priv);
if (ret)
dev_err(dev, "failed to disable VBUS supply (ret=%d)\n", ret);
reset_err:
ret = reset_release_bulk(&priv->resets);
if (ret)
dev_err(dev, "failed to release resets (ret=%d)\n", ret);
clk_err:
ret = clk_release_bulk(&priv->clocks);
if (ret)
dev_err(dev, "failed to release clocks (ret=%d)\n", ret);
return err;
}
static int ehci_usb_remove(struct udevice *dev)
{
struct generic_ehci *priv = dev_get_priv(dev);
int ret;
ret = ehci_deregister(dev);
if (ret)
return ret;
ret = ehci_shutdown_phy(dev, &priv->phy);
if (ret)
return ret;
ret = ehci_disable_vbus_supply(priv);
if (ret)
return ret;
ret = reset_release_bulk(&priv->resets);
if (ret)
return ret;
return clk_release_bulk(&priv->clocks);
}
static const struct udevice_id ehci_usb_ids[] = {
{ .compatible = "generic-ehci" },
{ }
};
U_BOOT_DRIVER(ehci_generic) = {
.name = "ehci_generic",
.id = UCLASS_USB,
.of_match = ehci_usb_ids,
.probe = ehci_usb_probe,
.remove = ehci_usb_remove,
.ops = &ehci_usb_ops,
.priv_auto = sizeof(struct generic_ehci),
.flags = DM_FLAG_ALLOC_PRIV_DMA,
};