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>

2 files changed, 22 insertions, 8 deletions

diff --git a/src/soc/nvidia/tegra124/spi.c b/src/soc/nvidia/tegra124/spi.c
index 0cb48657d6..5d8084fbdf 100644
--- a/src/soc/nvidia/tegra124/spi.c
+++ b/src/soc/nvidia/tegra124/spi.c
@@ -209,7 +209,7 @@ static unsigned int tegra_spi_speed(unsigned int bus)
 	return 50000000;
 }
 
-int spi_claim_bus(const struct spi_slave *slave)
+static int spi_ctrlr_claim_bus(const struct spi_slave *slave)
 {
 	struct tegra_spi_regs *regs = to_tegra_spi(slave->bus)->regs;
 	u32 val;
@@ -232,7 +232,7 @@ int spi_claim_bus(const struct spi_slave *slave)
 	return 0;
 }
 
-void spi_release_bus(const struct spi_slave *slave)
+static void spi_ctrlr_release_bus(const struct spi_slave *slave)
 {
 	struct tegra_spi_regs *regs = to_tegra_spi(slave->bus)->regs;
 	u32 val;
@@ -719,8 +719,8 @@ unsigned int spi_crop_chunk(unsigned int cmd_len, unsigned int buf_len)
 	return buf_len;
 }
 
-int spi_xfer(const struct spi_slave *slave, const void *dout,
-	     size_t out_bytes, void *din, size_t in_bytes)
+static int spi_ctrlr_xfer(const struct spi_slave *slave, const void *dout,
+			  size_t out_bytes, void *din, size_t in_bytes)
 {
 	struct tegra_spi_channel *spi = to_tegra_spi(slave->bus);
 	u8 *out_buf = (u8 *)dout;
@@ -798,6 +798,12 @@ int spi_xfer(const struct spi_slave *slave, const void *dout,
 	return ret;
 }
 
+static const struct spi_ctrlr spi_ctrlr = {
+	.claim_bus = spi_ctrlr_claim_bus,
+	.release_bus = spi_ctrlr_release_bus,
+	.xfer = spi_ctrlr_xfer,
+};
+
 int spi_setup_slave(unsigned int bus, unsigned int cs, struct spi_slave *slave)
 {
 	struct tegra_spi_channel *channel = to_tegra_spi(bus);
@@ -806,6 +812,7 @@ int spi_setup_slave(unsigned int bus, unsigned int cs, struct spi_slave *slave)
 
 	slave->bus = channel->slave.bus;
 	slave->cs = channel->slave.cs;
+	slave->ctrlr = &spi_ctrlr;
 
 	return 0;
 }
diff --git a/src/soc/nvidia/tegra210/spi.c b/src/soc/nvidia/tegra210/spi.c
index 3a2dd17230..292135542a 100644
--- a/src/soc/nvidia/tegra210/spi.c
+++ b/src/soc/nvidia/tegra210/spi.c
@@ -208,7 +208,7 @@ static struct tegra_spi_channel * const to_tegra_spi(int bus) {
 	return &tegra_spi_channels[bus - 1];
 }
 
-int spi_claim_bus(const struct spi_slave *slave)
+static int spi_ctrlr_claim_bus(const struct spi_slave *slave)
 {
 	struct tegra_spi_regs *regs = to_tegra_spi(slave->bus)->regs;
 	u32 val;
@@ -231,7 +231,7 @@ int spi_claim_bus(const struct spi_slave *slave)
 	return 0;
 }
 
-void spi_release_bus(const struct spi_slave *slave)
+static void spi_ctrlr_release_bus(const struct spi_slave *slave)
 {
 	struct tegra_spi_regs *regs = to_tegra_spi(slave->bus)->regs;
 	u32 val;
@@ -755,8 +755,8 @@ unsigned int spi_crop_chunk(unsigned int cmd_len, unsigned int buf_len)
 	return buf_len;
 }
 
-int spi_xfer(const struct spi_slave *slave, const void *dout,
-	     size_t out_bytes, void *din, size_t in_bytes)
+static int spi_ctrlr_xfer(const struct spi_slave *slave, const void *dout,
+			  size_t out_bytes, void *din, size_t in_bytes)
 {
 	struct tegra_spi_channel *spi = to_tegra_spi(slave->bus);
 	u8 *out_buf = (u8 *)dout;
@@ -834,6 +834,12 @@ int spi_xfer(const struct spi_slave *slave, const void *dout,
 	return ret;
 }
 
+static const struct spi_ctrlr spi_ctrlr = {
+	.claim_bus = spi_ctrlr_claim_bus,
+	.release_bus = spi_ctrlr_release_bus,
+	.xfer = spi_ctrlr_xfer,
+};
+
 int spi_setup_slave(unsigned int bus, unsigned int cs, struct spi_slave *slave)
 {
 	struct tegra_spi_channel *channel = to_tegra_spi(bus);
@@ -842,6 +848,7 @@ int spi_setup_slave(unsigned int bus, unsigned int cs, struct spi_slave *slave)
 
 	slave->cs = channel->slave.cs;
 	slave->bus = channel->slave.bus;
+	slave->ctrlr = &spi_ctrlr;
 
 	return 0;
 }