spi: Define and use spi_ctrlr structure

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>

1 files changed, 14 insertions, 20 deletions

diff --git a/src/soc/intel/fsp_baytrail/spi.c b/src/soc/intel/fsp_baytrail/spi.c
index 06b160c8b5..997bd138ae 100644
--- a/src/soc/intel/fsp_baytrail/spi.c
+++ b/src/soc/intel/fsp_baytrail/spi.c
@@ -249,13 +249,6 @@ static void read_reg(const void *src, void *value, uint32_t size)
 	}
 }
 
-int spi_setup_slave(unsigned int bus, unsigned int cs, struct spi_slave *slave)
-{
-	slave->bus = bus;
-	slave->cs = cs;
-	return 0;
-}
-
 static ich9_spi_regs *spi_regs(void)
 {
 	device_t dev;
@@ -288,17 +281,6 @@ void spi_init(void)
 	cntlr.preop = &ich9_spi->preop;
 }
 
-int spi_claim_bus(const struct spi_slave *slave)
-{
-	/* Handled by ICH automatically. */
-	return 0;
-}
-
-void spi_release_bus(const struct spi_slave *slave)
-{
-	/* Handled by ICH automatically. */
-}
-
 typedef struct spi_transaction {
 	const uint8_t *out;
 	uint32_t bytesout;
@@ -460,8 +442,8 @@ unsigned int spi_crop_chunk(unsigned int cmd_len, unsigned int buf_len)
 	return min(cntlr.databytes, buf_len);
 }
 
-int spi_xfer(const struct spi_slave *slave, const void *dout,
-		size_t bytesout, void *din, size_t bytesin)
+static int spi_ctrlr_xfer(const struct spi_slave *slave, const void *dout,
+		    size_t bytesout, void *din, size_t bytesin)
 {
 	uint16_t control;
 	int16_t opcode_index;
@@ -607,3 +589,15 @@ spi_xfer_exit:
 
 	return 0;
 }
+
+static const struct spi_ctrlr spi_ctrlr = {
+	.xfer = spi_ctrlr_xfer,
+};
+
+int spi_setup_slave(unsigned int bus, unsigned int cs, struct spi_slave *slave)
+{
+	slave->bus = bus;
+	slave->cs = cs;
+	slave->ctrlr = &spi_ctrlr;
+	return 0;
+}