From b5d41cb063a54d2a90e0480ede18d3b9c1ae8474 Mon Sep 17 00:00:00 2001 From: Furquan Shaikh Date: Thu, 1 Dec 2016 07:25:31 -0800 Subject: spi: Clean up SPI driver interface 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 Reviewed-on: https://review.coreboot.org/17561 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin --- src/drivers/spi/spi-generic.c | 35 +++++++++++++++++++++++++++++++++++ src/include/spi-generic.h | 19 +++++++++++++++++++ 2 files changed, 54 insertions(+) diff --git a/src/drivers/spi/spi-generic.c b/src/drivers/spi/spi-generic.c index 7398ee928f..4fcd04c13a 100644 --- a/src/drivers/spi/spi-generic.c +++ b/src/drivers/spi/spi-generic.c @@ -41,3 +41,38 @@ int spi_xfer(const struct spi_slave *slave, const void *dout, size_t bytesout, return -1; } + +void __attribute__((weak)) spi_init(void) +{ + /* Default weak implementation - do nothing. */ +} + +const struct spi_ctrlr_buses spi_ctrlr_bus_map[0] __attribute__((weak)); +const size_t spi_ctrlr_bus_map_count __attribute__((weak)); + +int __attribute__((weak)) spi_setup_slave(unsigned int bus, unsigned int cs, + struct spi_slave *slave) +{ + size_t i; + + memset(slave, 0, sizeof(*slave)); + + for (i = 0; i < spi_ctrlr_bus_map_count; i++) { + if ((spi_ctrlr_bus_map[i].bus_start <= bus) && + (spi_ctrlr_bus_map[i].bus_end >= bus)) { + slave->ctrlr = spi_ctrlr_bus_map[i].ctrlr; + break; + } + } + + if (slave->ctrlr == NULL) + return -1; + + slave->bus = bus; + slave->cs = cs; + + if (slave->ctrlr->setup) + return slave->ctrlr->setup(slave); + + return 0; +} diff --git a/src/include/spi-generic.h b/src/include/spi-generic.h index b4a10af0c0..d28fefd026 100644 --- a/src/include/spi-generic.h +++ b/src/include/spi-generic.h @@ -42,14 +42,33 @@ struct spi_slave { * claim_bus: Claim SPI bus and prepare for communication. * release_bus: Release SPI bus. * xfer: SPI transfer + * setup: Setup given SPI device bus. */ struct spi_ctrlr { int (*claim_bus)(const struct spi_slave *slave); void (*release_bus)(const struct spi_slave *slave); int (*xfer)(const struct spi_slave *slave, const void *dout, size_t bytesout, void *din, size_t bytesin); + int (*setup)(const struct spi_slave *slave); }; +/*----------------------------------------------------------------------- + * Structure defining mapping of SPI buses to controller. + * + * ctrlr: Pointer to controller structure managing the given SPI buses. + * bus_start: Start bus number managed by the controller. + * bus_end: End bus number manager by the controller. + */ +struct spi_ctrlr_buses { + const struct spi_ctrlr *ctrlr; + unsigned int bus_start; + unsigned int bus_end; +}; + +/* Mapping of SPI buses to controllers - should be defined by platform. */ +extern const struct spi_ctrlr_buses spi_ctrlr_bus_map[]; +extern const size_t spi_ctrlr_bus_map_count; + /*----------------------------------------------------------------------- * Initialization, must be called once on start up. * -- cgit v1.2.3