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-rw-r--r--include/linux/spi/spi-mem.h249
1 files changed, 249 insertions, 0 deletions
diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h
new file mode 100644
index 000000000000..bb4bd15ae1f6
--- /dev/null
+++ b/include/linux/spi/spi-mem.h
@@ -0,0 +1,249 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2018 Exceet Electronics GmbH
+ * Copyright (C) 2018 Bootlin
+ *
+ * Author: Boris Brezillon <boris.brezillon@bootlin.com>
+ */
+
+#ifndef __LINUX_SPI_MEM_H
+#define __LINUX_SPI_MEM_H
+
+#include <linux/spi/spi.h>
+
+#define SPI_MEM_OP_CMD(__opcode, __buswidth) \
+ { \
+ .buswidth = __buswidth, \
+ .opcode = __opcode, \
+ }
+
+#define SPI_MEM_OP_ADDR(__nbytes, __val, __buswidth) \
+ { \
+ .nbytes = __nbytes, \
+ .val = __val, \
+ .buswidth = __buswidth, \
+ }
+
+#define SPI_MEM_OP_NO_ADDR { }
+
+#define SPI_MEM_OP_DUMMY(__nbytes, __buswidth) \
+ { \
+ .nbytes = __nbytes, \
+ .buswidth = __buswidth, \
+ }
+
+#define SPI_MEM_OP_NO_DUMMY { }
+
+#define SPI_MEM_OP_DATA_IN(__nbytes, __buf, __buswidth) \
+ { \
+ .dir = SPI_MEM_DATA_IN, \
+ .nbytes = __nbytes, \
+ .buf.in = __buf, \
+ .buswidth = __buswidth, \
+ }
+
+#define SPI_MEM_OP_DATA_OUT(__nbytes, __buf, __buswidth) \
+ { \
+ .dir = SPI_MEM_DATA_OUT, \
+ .nbytes = __nbytes, \
+ .buf.out = __buf, \
+ .buswidth = __buswidth, \
+ }
+
+#define SPI_MEM_OP_NO_DATA { }
+
+/**
+ * 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 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 cycles
+ * @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 lanes used to transmit the dummy bytes
+ * @data.buswidth: number of IO lanes used to send/receive the data
+ * @data.dir: direction of the transfer
+ * @data.buf.in: input buffer
+ * @data.buf.out: output buffer
+ */
+struct spi_mem_op {
+ struct {
+ u8 buswidth;
+ u8 opcode;
+ } cmd;
+
+ struct {
+ u8 nbytes;
+ u8 buswidth;
+ u64 val;
+ } addr;
+
+ struct {
+ u8 nbytes;
+ u8 buswidth;
+ } dummy;
+
+ struct {
+ u8 buswidth;
+ enum spi_mem_data_dir dir;
+ unsigned int nbytes;
+ /* buf.{in,out} must be DMA-able. */
+ union {
+ void *in;
+ const void *out;
+ } buf;
+ } data;
+};
+
+#define SPI_MEM_OP(__cmd, __addr, __dummy, __data) \
+ { \
+ .cmd = __cmd, \
+ .addr = __addr, \
+ .dummy = __dummy, \
+ .data = __data, \
+ }
+
+/**
+ * struct spi_mem - describes a SPI memory device
+ * @spi: the underlying SPI device
+ * @drvpriv: spi_mem_drviver private data
+ *
+ * Extra information that describe the SPI memory device and may be needed by
+ * the controller to properly handle this device should be placed here.
+ *
+ * One example would be the device size since some controller expose their SPI
+ * mem devices through a io-mapped region.
+ */
+struct spi_mem {
+ struct spi_device *spi;
+ void *drvpriv;
+};
+
+/**
+ * struct spi_mem_set_drvdata() - attach driver private data to a SPI mem
+ * device
+ * @mem: memory device
+ * @data: data to attach to the memory device
+ */
+static inline void spi_mem_set_drvdata(struct spi_mem *mem, void *data)
+{
+ mem->drvpriv = data;
+}
+
+/**
+ * struct spi_mem_get_drvdata() - get driver private data attached to a SPI mem
+ * device
+ * @mem: memory device
+ *
+ * Return: the data attached to the mem device.
+ */
+static inline void *spi_mem_get_drvdata(struct spi_mem *mem)
+{
+ return mem->drvpriv;
+}
+
+/**
+ * struct spi_controller_mem_ops - SPI memory operations
+ * @adjust_op_size: shrink the data xfer of an operation to match controller's
+ * limitations (can be alignment of max RX/TX size
+ * limitations)
+ * @supports_op: check if an operation is supported by the controller
+ * @exec_op: execute a SPI memory operation
+ *
+ * This interface should be implemented by SPI controllers providing an
+ * high-level interface to execute SPI memory operation, which is usually the
+ * case for QSPI controllers.
+ */
+struct spi_controller_mem_ops {
+ int (*adjust_op_size)(struct spi_mem *mem, struct spi_mem_op *op);
+ bool (*supports_op)(struct spi_mem *mem,
+ const struct spi_mem_op *op);
+ int (*exec_op)(struct spi_mem *mem,
+ const struct spi_mem_op *op);
+};
+
+/**
+ * struct spi_mem_driver - SPI memory driver
+ * @spidrv: inherit from a SPI driver
+ * @probe: probe a SPI memory. Usually where detection/initialization takes
+ * place
+ * @remove: remove a SPI memory
+ * @shutdown: take appropriate action when the system is shutdown
+ *
+ * This is just a thin wrapper around a spi_driver. The core takes care of
+ * allocating the spi_mem object and forwarding the probe/remove/shutdown
+ * request to the spi_mem_driver. The reason we use this wrapper is because
+ * we might have to stuff more information into the spi_mem struct to let
+ * SPI controllers know more about the SPI memory they interact with, and
+ * having this intermediate layer allows us to do that without adding more
+ * useless fields to the spi_device object.
+ */
+struct spi_mem_driver {
+ struct spi_driver spidrv;
+ int (*probe)(struct spi_mem *mem);
+ int (*remove)(struct spi_mem *mem);
+ void (*shutdown)(struct spi_mem *mem);
+};
+
+#if IS_ENABLED(CONFIG_SPI_MEM)
+int spi_controller_dma_map_mem_op_data(struct spi_controller *ctlr,
+ const struct spi_mem_op *op,
+ struct sg_table *sg);
+
+void spi_controller_dma_unmap_mem_op_data(struct spi_controller *ctlr,
+ const struct spi_mem_op *op,
+ struct sg_table *sg);
+#else
+static inline int
+spi_controller_dma_map_mem_op_data(struct spi_controller *ctlr,
+ const struct spi_mem_op *op,
+ struct sg_table *sg)
+{
+ return -ENOTSUPP;
+}
+
+static inline void
+spi_controller_dma_unmap_mem_op_data(struct spi_controller *ctlr,
+ const struct spi_mem_op *op,
+ struct sg_table *sg)
+{
+}
+#endif /* CONFIG_SPI_MEM */
+
+int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op);
+
+bool spi_mem_supports_op(struct spi_mem *mem,
+ const struct spi_mem_op *op);
+
+int spi_mem_exec_op(struct spi_mem *mem,
+ const struct spi_mem_op *op);
+
+int spi_mem_driver_register_with_owner(struct spi_mem_driver *drv,
+ struct module *owner);
+
+void spi_mem_driver_unregister(struct spi_mem_driver *drv);
+
+#define spi_mem_driver_register(__drv) \
+ spi_mem_driver_register_with_owner(__drv, THIS_MODULE)
+
+#define module_spi_mem_driver(__drv) \
+ module_driver(__drv, spi_mem_driver_register, \
+ spi_mem_driver_unregister)
+
+#endif /* __LINUX_SPI_MEM_H */