summaryrefslogtreecommitdiff
path: root/drivers/usb
diff options
context:
space:
mode:
authorFabrice Gasnier <fabrice.gasnier@foss.st.com>2022-12-12 11:44:35 +0100
committerPatrice Chotard <patrice.chotard@foss.st.com>2023-01-12 16:19:53 +0100
commitba1fa2abde88257c29ee4d8f3884ab6657a3193a (patch)
treefedeefef60560b17e84e797192723a757e4577bd /drivers/usb
parent79da4074ddf0f76b3c2ec26d58c9a33ac7884222 (diff)
downloadu-boot-ba1fa2abde88257c29ee4d8f3884ab6657a3193a.tar.gz
usb: onboard-hub: add driver to manage onboard hub supplies
The main issue the driver addresses is that a USB hub needs to be powered before it can be discovered. This is often solved by using "regulator-always-on". This driver is inspired by the Linux v6.1 driver. It only enables (or disables) the hub vdd (3v3) supply, so it can be enumerated. Scanning of the device tree is done in a similar manner to the sandbox, by the usb-uclass. DT part looks like: &usbh_ehci { ... #address-cells = <1>; #size-cells = <0>; hub@1 { compatible = "usb424,2514"; reg = <1>; vdd-supply = <&v3v3>; }; }; When the bus gets probed, the driver is automatically probed/removed from the bus tree, as an example on stm32: STM32MP> usb start starting USB... STM32MP> dm tree Class Index Probed Driver Name ----------------------------------------------------------- usb 0 [ + ] ehci_generic | |-- usb@5800d000 usb_hub 0 [ + ] usb_onboard_hub | | `-- hub@1 usb_hub 1 [ + ] usb_hub | | `-- usb_hub STM32MP> usb tree USB device tree: 1 Hub (480 Mb/s, 0mA) | u-boot EHCI Host Controller | +-2 Hub (480 Mb/s, 2mA) Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com> Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Diffstat (limited to 'drivers/usb')
-rw-r--r--drivers/usb/Kconfig10
-rw-r--r--drivers/usb/host/usb-uclass.c16
2 files changed, 20 insertions, 6 deletions
diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index 8efd461457..ebe6bf9498 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -105,6 +105,16 @@ config USB_KEYBOARD
Say Y here if you want to use a USB keyboard for U-Boot command line
input.
+config USB_ONBOARD_HUB
+ bool "Onboard USB hub support"
+ depends on DM_USB
+ ---help---
+ Say Y here if you want to support discrete onboard USB hubs that
+ don't require an additional control bus for initialization, but
+ need some non-trivial form of initialization, such as enabling a
+ power regulator. An example for such a hub is the Microchip
+ USB2514B.
+
if USB_KEYBOARD
config USB_KEYBOARD_FN_KEYS
diff --git a/drivers/usb/host/usb-uclass.c b/drivers/usb/host/usb-uclass.c
index 956e2a4e8e..93c318c3d1 100644
--- a/drivers/usb/host/usb-uclass.c
+++ b/drivers/usb/host/usb-uclass.c
@@ -271,19 +271,23 @@ int usb_init(void)
/* init low_level USB */
printf("Bus %s: ", bus->name);
-#ifdef CONFIG_SANDBOX
/*
* For Sandbox, we need scan the device tree each time when we
* start the USB stack, in order to re-create the emulated USB
* devices and bind drivers for them before we actually do the
* driver probe.
+ *
+ * For USB onboard HUB, we need to do some non-trivial init
+ * like enabling a power regulator, before enumeration.
*/
- ret = dm_scan_fdt_dev(bus);
- if (ret) {
- printf("Sandbox USB device scan failed (%d)\n", ret);
- continue;
+ if (IS_ENABLED(CONFIG_SANDBOX) ||
+ IS_ENABLED(CONFIG_USB_ONBOARD_HUB)) {
+ ret = dm_scan_fdt_dev(bus);
+ if (ret) {
+ printf("USB device scan from fdt failed (%d)", ret);
+ continue;
+ }
}
-#endif
ret = device_probe(bus);
if (ret == -ENODEV) { /* No such device. */