spi: Add function callback to get configuration of SPI bus
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>
diff --git a/src/arch/x86/include/arch/acpi_device.h b/src/arch/x86/include/arch/acpi_device.h
index 6e8f812..aba5c2d 100644
--- a/src/arch/x86/include/arch/acpi_device.h
+++ b/src/arch/x86/include/arch/acpi_device.h
@@ -18,6 +18,7 @@
#include <device/i2c.h>
#include <stdint.h>
+#include <spi-generic.h>
#define ACPI_DESCRIPTOR_LARGE (1 << 7)
#define ACPI_DESCRIPTOR_INTERRUPT (ACPI_DESCRIPTOR_LARGE | 9)
@@ -216,23 +217,6 @@
* ACPI SPI Bus
*/
-enum spi_clock_phase {
- SPI_CLOCK_PHASE_FIRST,
- SPI_CLOCK_PHASE_SECOND
-};
-
-/* SPI Flags bit 0 */
-enum spi_wire_mode {
- SPI_4_WIRE_MODE,
- SPI_3_WIRE_MODE
-};
-
-/* SPI Flags bit 1 */
-enum spi_polarity {
- SPI_POLARITY_LOW,
- SPI_POLARITY_HIGH
-};
-
struct acpi_spi {
/* Device selection */
uint16_t device_select;
diff --git a/src/drivers/spi/spi-generic.c b/src/drivers/spi/spi-generic.c
index 805e17a..3ef437c 100644
--- a/src/drivers/spi/spi-generic.c
+++ b/src/drivers/spi/spi-generic.c
@@ -88,6 +88,16 @@
return -1;
}
+int spi_get_config(const struct spi_slave *slave, struct spi_cfg *cfg)
+{
+ const struct spi_ctrlr *ctrlr = slave->ctrlr;
+
+ if (ctrlr && ctrlr->get_config)
+ return ctrlr->get_config(slave, cfg);
+
+ return -1;
+}
+
void __attribute__((weak)) spi_init(void)
{
/* Default weak implementation - do nothing. */
diff --git a/src/include/spi-generic.h b/src/include/spi-generic.h
index 7eb18a6..cc3d3cf 100644
--- a/src/include/spi-generic.h
+++ b/src/include/spi-generic.h
@@ -59,9 +59,38 @@
enum spi_op_status status;
};
+enum spi_clock_phase {
+ SPI_CLOCK_PHASE_FIRST,
+ SPI_CLOCK_PHASE_SECOND
+};
+
+enum spi_wire_mode {
+ SPI_4_WIRE_MODE,
+ SPI_3_WIRE_MODE
+};
+
+enum spi_polarity {
+ SPI_POLARITY_LOW,
+ SPI_POLARITY_HIGH
+};
+
+struct spi_cfg {
+ /* CLK phase - 0: Phase first, 1: Phase second */
+ enum spi_clock_phase clk_phase;
+ /* CLK polarity - 0: Low, 1: High */
+ enum spi_polarity clk_polarity;
+ /* CS polarity - 0: Low, 1: High */
+ enum spi_polarity cs_polarity;
+ /* Wire mode - 0: 4-wire, 1: 3-wire */
+ enum spi_wire_mode wire_mode;
+ /* Data bit length. */
+ unsigned int data_bit_length;
+};
+
/*-----------------------------------------------------------------------
* Representation of a SPI contoller.
*
+ * get_config: Get configuration of SPI bus
* claim_bus: Claim SPI bus and prepare for communication.
* release_bus: Release SPI bus.
* setup: Setup given SPI device bus.
@@ -69,6 +98,8 @@
* xfer_vector: Vector of SPI transfer operations.
*/
struct spi_ctrlr {
+ int (*get_config)(const struct spi_slave *slave,
+ struct spi_cfg *cfg);
int (*claim_bus)(const struct spi_slave *slave);
void (*release_bus)(const struct spi_slave *slave);
int (*setup)(const struct spi_slave *slave);
@@ -101,6 +132,17 @@
*/
void spi_init(void);
+/*
+ * Get configuration of SPI bus.
+ *
+ * slave: Pointer to slave structure.
+ * cfg: Pointer to SPI configuration that needs to be filled.
+ *
+ * Returns:
+ * 0 on success, -1 on error
+ */
+int spi_get_config(const struct spi_slave *slave, struct spi_cfg *cfg);
+
/*-----------------------------------------------------------------------
* Set up communications parameters for a SPI slave.
*