1 files changed, 130 insertions, 0 deletions
diff --git a/include/drivers/spi_mem.h b/include/drivers/spi_mem.h
new file mode 100644
index 0000000..d1953ac
--- /dev/null
+++ b/include/drivers/spi_mem.h
@@ -0,0 +1,130 @@
+/*
+ * Copyright (c) 2019, STMicroelectronics - All Rights Reserved
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef DRIVERS_SPI_MEM_H
+#define DRIVERS_SPI_MEM_H
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#define SPI_MEM_BUSWIDTH_1_LINE		1U
+#define SPI_MEM_BUSWIDTH_2_LINE		2U
+#define SPI_MEM_BUSWIDTH_4_LINE		4U
+
+/*
+ * enum spi_mem_data_dir - Describes the direction of a SPI memory data
+ *			   transfer from the controller perspective.
+ * @SPI_MEM_DATA_IN: data coming from the SPI memory.
+ * @SPI_MEM_DATA_OUT: data sent to the SPI memory.
+ */
+enum spi_mem_data_dir {
+	SPI_MEM_DATA_IN,
+	SPI_MEM_DATA_OUT,
+};
+
+/*
+ * struct spi_mem_op - Describes a SPI memory operation.
+ *
+ * @cmd.buswidth: Number of IO lines used to transmit the command.
+ * @cmd.opcode: Operation opcode.
+ * @addr.nbytes: Number of address bytes to send. Can be zero if the operation
+ *		 does not need to send an address.
+ * @addr.buswidth: Number of IO lines used to transmit the address.
+ * @addr.val: Address value. This value is always sent MSB first on the bus.
+ *	      Note that only @addr.nbytes are taken into account in this
+ *	      address value, so users should make sure the value fits in the
+ *	      assigned number of bytes.
+ * @dummy.nbytes: Number of dummy bytes to send after an opcode or address. Can
+ *		  be zero if the operation does not require dummy bytes.
+ * @dummy.buswidth: Number of IO lines used to transmit the dummy bytes.
+ * @data.buswidth: Number of IO lines used to send/receive the data.
+ * @data.dir: Direction of the transfer.
+ * @data.nbytes: Number of data bytes to transfer.
+ * @data.buf: Input or output data buffer depending on data::dir.
+ */
+struct spi_mem_op {
+	struct {
+		uint8_t buswidth;
+		uint8_t opcode;
+	} cmd;
+
+	struct {
+		uint8_t nbytes;
+		uint8_t buswidth;
+		uint64_t val;
+	} addr;
+
+	struct {
+		uint8_t nbytes;
+		uint8_t buswidth;
+	} dummy;
+
+	struct {
+		uint8_t buswidth;
+		enum spi_mem_data_dir dir;
+		unsigned int nbytes;
+		void *buf;
+	} data;
+};
+
+/* SPI mode flags */
+#define SPI_CPHA	BIT(0)			/* clock phase */
+#define SPI_CPOL	BIT(1)			/* clock polarity */
+#define SPI_CS_HIGH	BIT(2)			/* CS active high */
+#define SPI_LSB_FIRST	BIT(3)			/* per-word bits-on-wire */
+#define SPI_3WIRE	BIT(4)			/* SI/SO signals shared */
+#define SPI_PREAMBLE	BIT(5)			/* Skip preamble bytes */
+#define SPI_TX_DUAL	BIT(6)			/* transmit with 2 wires */
+#define SPI_TX_QUAD	BIT(7)			/* transmit with 4 wires */
+#define SPI_RX_DUAL	BIT(8)			/* receive with 2 wires */
+#define SPI_RX_QUAD	BIT(9)			/* receive with 4 wires */
+
+struct spi_bus_ops {
+	/*
+	 * Claim the bus and prepare it for communication.
+	 *
+	 * @cs:	The chip select.
+	 * Returns: 0 if the bus was claimed successfully, or a negative value
+	 * if it wasn't.
+	 */
+	int (*claim_bus)(unsigned int cs);
+
+	/*
+	 * Release the SPI bus.
+	 */
+	void (*release_bus)(void);
+
+	/*
+	 * Set transfer speed.
+	 *
+	 * @hz:	The transfer speed in Hertz.
+	 * Returns: 0 on success, a negative error code otherwise.
+	 */
+	int (*set_speed)(unsigned int hz);
+
+	/*
+	 * Set the SPI mode/flags.
+	 *
+	 * @mode: Requested SPI mode (SPI_... flags).
+	 * Returns: 0 on success, a negative error code otherwise.
+	 */
+	int (*set_mode)(unsigned int mode);
+
+	/*
+	 * Execute a SPI memory operation.
+	 *
+	 * @op:	The memory operation to execute.
+	 * Returns: 0 on success, a negative error code otherwise.
+	 */
+	int (*exec_op)(const struct spi_mem_op *op);
+};
+
+int spi_mem_exec_op(const struct spi_mem_op *op);
+int spi_mem_init_slave(void *fdt, int bus_node,
+		       const struct spi_bus_ops *ops);
+
+#endif /* DRIVERS_SPI_MEM_H */