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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
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Adding upstream version 6.1.76.upstream/6.1.76upstream
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+========================
+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 arch/arm/mach-s3c,
+ 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 include/linux/platform_data/usb-ohci-s3c2410.h for the
+ descriptions of the platform device data. An implementation
+ can be found in arch/arm/mach-s3c/simtec-usb.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