From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- Documentation/arm/samsung-s3c24xx/usb-host.rst | 91 ++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 Documentation/arm/samsung-s3c24xx/usb-host.rst (limited to 'Documentation/arm/samsung-s3c24xx/usb-host.rst') diff --git a/Documentation/arm/samsung-s3c24xx/usb-host.rst b/Documentation/arm/samsung-s3c24xx/usb-host.rst new file mode 100644 index 000000000..c84268bd1 --- /dev/null +++ b/Documentation/arm/samsung-s3c24xx/usb-host.rst @@ -0,0 +1,91 @@ +======================== +S3C24XX USB Host support +======================== + + + +Introduction +------------ + + This document details the S3C2410/S3C2440 in-built OHCI USB host support. + +Configuration +------------- + + Enable at least the following kernel options: + + menuconfig:: + + Device Drivers ---> + USB support ---> + <*> Support for Host-side USB + <*> OHCI HCD support + + + .config: + + - CONFIG_USB + - CONFIG_USB_OHCI_HCD + + + Once these options are configured, the standard set of USB device + drivers can be configured and used. + + +Board Support +------------- + + The driver attaches to a platform device, which will need to be + added by the board specific support file in linux/arch/arm/mach-s3c2410, + such as mach-bast.c or mach-smdk2410.c + + The platform device's platform_data field is only needed if the + board implements extra power control or over-current monitoring. + + The OHCI driver does not ensure the state of the S3C2410's MISCCTRL + register, so if both ports are to be used for the host, then it is + the board support file's responsibility to ensure that the second + port is configured to be connected to the OHCI core. + + +Platform Data +------------- + + See arch/arm/mach-s3c2410/include/mach/usb-control.h for the + descriptions of the platform device data. An implementation + can be found in linux/arch/arm/mach-s3c2410/usb-simtec.c . + + The `struct s3c2410_hcd_info` contains a pair of functions + that get called to enable over-current detection, and to + control the port power status. + + The ports are numbered 0 and 1. + + power_control: + Called to enable or disable the power on the port. + + enable_oc: + Called to enable or disable the over-current monitoring. + This should claim or release the resources being used to + check the power condition on the port, such as an IRQ. + + report_oc: + The OHCI driver fills this field in for the over-current code + to call when there is a change to the over-current state on + an port. The ports argument is a bitmask of 1 bit per port, + with bit X being 1 for an over-current on port X. + + The function s3c2410_usb_report_oc() has been provided to + ensure this is called correctly. + + port[x]: + This is struct describes each port, 0 or 1. The platform driver + should set the flags field of each port to S3C_HCDFLG_USED if + the port is enabled. + + + +Document Author +--------------- + +Ben Dooks, Copyright 2005 Simtec Electronics -- cgit v1.2.3