[coreboot-gerrit] Patch set updated for coreboot: spi: Clean up SPI driver interface

[Furquan Shaikh (furquan@google.com)]

Furquan Shaikh (furquan at google.com) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/17561

-gerrit

commit 86232531de852b80e718dfe215e95eaac030dd52
Author: Furquan Shaikh <furquan at chromium.org>
Date:   Thu Dec 1 07:25:31 2016 -0800

    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 <furquan at chromium.org>
---
 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 7398ee9..4fcd04c 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 b4a10af..d28fefd 100644
--- a/src/include/spi-generic.h
+++ b/src/include/spi-generic.h
@@ -42,15 +42,34 @@ 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.
  *
  */