summaryrefslogtreecommitdiff
path: root/src/drivers/spi/spi-generic.c
AgeCommit message (Collapse)Author
2017-02-16spi: Add function callback to get configuration of SPI busFurquan Shaikh
Add a new callback to spi_ctrlr structure - get_config - to obtain configuration of SPI bus from the controller driver. Also, move common config definitions from acpi_device.h to spi-generic.h BUG=chrome-os-partner:59832 BRANCH=None TEST=Compiles successfully Change-Id: I412c8c70167d18058a32041c2310bc1c884043ce Signed-off-by: Furquan Shaikh <furquan@chromium.org> Reviewed-on: https://review.coreboot.org/18337 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net> Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
2016-12-23spi: Get rid of SPI_ATOMIC_SEQUENCINGFurquan Shaikh
SPI_ATOMIC_SEQUENCING was added to accomodate spi flash controllers with the ability to perform tx and rx of flash command and response at the same time. Instead of introducing this notion at SPI flash driver layer, clean up the interface to SPI used by flash. Flash uses a command-response kind of communication. Thus, even though SPI is duplex, flash command needs to be sent out on SPI bus and then flash response should be received on the bus. Some specialized x86 flash controllers are capable of handling command and response in a single transaction. In order to support all the varied cases: 1. Add spi_xfer_vector that takes as input a vector of SPI operations and calls back into SPI controller driver to process these operations. 2. In order to accomodate flash command-response model, use two vectors while calling into spi_xfer_vector -- one with dout set to non-NULL(command) and other with din set to non-NULL(response). 3. For specialized SPI flash controllers combine two successive vectors if the transactions look like a command-response pair. 4. Provide helper functions for common cases like supporting only 2 vectors at a time, supporting n vectors at a time, default vector operation to cycle through all SPI op vectors one by one. BUG=chrome-os-partner:59832 BRANCH=None TEST=Compiles successfully Change-Id: I4c9e78c585ad95c40c0d5af078ff8251da286236 Signed-off-by: Furquan Shaikh <furquan@chromium.org> Reviewed-on: https://review.coreboot.org/17681 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2016-12-07spi: Clean up SPI driver interfaceFurquan Shaikh
1. Add new structure spi_ctrlr_buses that allows platform to define a mapping from SPI controller to buses managed by the controller. 2. Provide weak implementations of spi_init and spi_setup_slave that will be used by platforms using the new interface. BUG=chrome-os-partner:59832 BRANCH=None TEST=Compiles successfully Change-Id: Ia6f47941b786299f4d823895898ffb1b36e02f73 Signed-off-by: Furquan Shaikh <furquan@chromium.org> Reviewed-on: https://review.coreboot.org/17561 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2016-12-05spi: Define and use spi_ctrlr structureFurquan Shaikh
1. Define a new structure spi_ctrlr that allows platforms to define callbacks for spi operations (claim bus, release bus, transfer). 2. Add a new member (pointer to spi_ctrlr structure) in spi_slave structure which will be initialized by call to spi_setup_slave. 3. Define spi_claim_bus, spi_release_bus and spi_xfer in spi-generic.c which will make appropriate calls to ctrlr functions. BUG=chrome-os-partner:59832 BRANCH=None TEST=Compiles successfully Change-Id: Icb2326e3aab1e8f4bef53f553f82b3836358c55e Signed-off-by: Furquan Shaikh <furquan@chromium.org> Reviewed-on: https://review.coreboot.org/17684 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>