Although it is a single patch, I felt that a cover letter will definetly not hurt here, also the patch version history is so big, so I decided to move it here.
The ULPI (UTMI Low Pin (count) Interface) PHYs are widely used on variety of boards. This requires a generic architecture independant implementation which can be reused and will eliminate the need for direct write of arbitrary values to the ULPI transciever. Although, the generic implementation can be reused on any architecture, the access to ULPI PHY must be done in a platform specific way. The platform specific way is in majority of case called a viewport. Also, the ULPI specification defines a hybrid aproach for managing the ULPI PHY. That is, the PHY must be managed through both the PHY registers and control lines.
The proposed patch provides a partial implementation of the ULPI specification, which should be enough for boot loader use cases, and a viewport implementation for Chipidea/ARC based controllers, which, AFAIK, are used on imx and tegra SoCs.
It is based on the Wolfgang's master branch (4 Dec 2012), compile tested and checkpatch clean.
What is still missing, IMO: - documentation for the CONFIG_* macros (I can add it in a separate patch) - a way to make most of the initialization in one ulpi_init() call - viewport extension to be able to implement resume, reset and disabling the serial mode
The change log: Changes for v2: - make code EHCI-independent - use udelay() in waiting loop - mark static functions as static - naming changes Changes for v3: - merge with patch ulpi: add generic ULPI support header file - rewrite ULPI interface in more functionality-oriented way Changes for v4: - add error-checking - add waiting for completion into ulpi_reset() function Changes for v5: - CodingStyle changes - add comments - simplify implemenation of the ULPI interface functions Changes for v6: - cleanup function ulpi_drive_vbus() Changes for v7: - ulpi-viewport.c: - reorder bit definitions - split ulpi_request() to two functions - reuse ulpi_wakeup() from ulpi_request() to remove duplicated calls from ulpi_{read|write}() - inline ulpi_*_mask as it is simple and used only once - ulpi.c: - move several defines into c file - rework all the functions to propagate error values - move function description comments into ulpi.h along with declarations - check arguments validity (as suggested by Simon) - fix cases when using the *_set register, bits cannot be cleared - shorten several arguments names (e.g. ulpi_set_vbus()) - add ability to disable VBUS - clean up ulpi_set_pd() - add ability to enter the serial mode - add verbosity in error cases - remove ulpi_resume() as it were wrong and must be implemented in a viewport specific way - rework ulpi_reset() as it must be implemented in a viewport specific way, but provide kind of generic implementation which should work in most of the cases - ulpi.h: - add default timeout value - remove unused defines - move several defines inside c files - add description for each function - move the API declaration to the top of the header file
Jana Rapava (1): USB: Add generic ULPI layer and a viewport
Makefile | 1 + drivers/usb/ulpi/Makefile | 44 ++++++ drivers/usb/ulpi/ulpi-viewport.c | 118 +++++++++++++++ drivers/usb/ulpi/ulpi.c | 227 +++++++++++++++++++++++++++++ include/usb/ulpi.h | 298 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 688 insertions(+), 0 deletions(-) create mode 100644 drivers/usb/ulpi/Makefile create mode 100644 drivers/usb/ulpi/ulpi-viewport.c create mode 100644 drivers/usb/ulpi/ulpi.c create mode 100644 include/usb/ulpi.h