linux/mtd/hyperbus.h

0001 /* SPDX-License-Identifier: GPL-2.0
0002  *
0003  * Copyright (C) 2019 Texas Instruments Incorporated - https://www.ti.com/
0004  */
0005
0006 #ifndef __LINUX_MTD_HYPERBUS_H__
0007 #define __LINUX_MTD_HYPERBUS_H__
0008
0009 #include <linux/mtd/map.h>
0010
0011 /* HyperBus command bits */
0012 #define HYPERBUS_RW 0x80    /* R/W# */
0013 #define HYPERBUS_RW_WRITE 0
0014 #define HYPERBUS_RW_READ 0x80
0015 #define HYPERBUS_AS 0x40    /* Address Space */
0016 #define HYPERBUS_AS_MEM 0
0017 #define HYPERBUS_AS_REG 0x40
0018 #define HYPERBUS_BT 0x20    /* Burst Type */
0019 #define HYPERBUS_BT_WRAPPED 0
0020 #define HYPERBUS_BT_LINEAR 0x20
0021
0022 enum hyperbus_memtype {
0023     HYPERFLASH,
0024     HYPERRAM,
0025 };
0026
0027 /**
0028  * struct hyperbus_device - struct representing HyperBus slave device
0029  * @map: map_info struct for accessing MMIO HyperBus flash memory
0030  * @np: pointer to HyperBus slave device node
0031  * @mtd: pointer to MTD struct
0032  * @ctlr: pointer to HyperBus controller struct
0033  * @memtype: type of memory device: HyperFlash or HyperRAM
0034  * @priv: pointer to controller specific per device private data
0035  */
0036
0037 struct hyperbus_device {
0038     struct map_info map;
0039     struct device_node *np;
0040     struct mtd_info *mtd;
0041     struct hyperbus_ctlr *ctlr;
0042     enum hyperbus_memtype memtype;
0043     void *priv;
0044 };
0045
0046 /**
0047  * struct hyperbus_ops - struct representing custom HyperBus operations
0048  * @read16: read 16 bit of data from flash in a single burst. Used to read
0049  *          from non default address space, such as ID/CFI space
0050  * @write16: write 16 bit of data to flash in a single burst. Used to
0051  *           send cmd to flash or write single 16 bit word at a time.
0052  * @copy_from: copy data from flash memory
0053  * @copy_to: copy data to flash memory
0054  * @calibrate: calibrate HyperBus controller
0055  */
0056
0057 struct hyperbus_ops {
0058     u16 (*read16)(struct hyperbus_device *hbdev, unsigned long addr);
0059     void (*write16)(struct hyperbus_device *hbdev,
0060             unsigned long addr, u16 val);
0061     void (*copy_from)(struct hyperbus_device *hbdev, void *to,
0062               unsigned long from, ssize_t len);
0063     void (*copy_to)(struct hyperbus_device *dev, unsigned long to,
0064             const void *from, ssize_t len);
0065     int (*calibrate)(struct hyperbus_device *dev);
0066 };
0067
0068 /**
0069  * struct hyperbus_ctlr - struct representing HyperBus controller
0070  * @dev: pointer to HyperBus controller device
0071  * @calibrated: flag to indicate ctlr calibration sequence is complete
0072  * @ops: HyperBus controller ops
0073  */
0074 struct hyperbus_ctlr {
0075     struct device *dev;
0076     bool calibrated;
0077
0078     const struct hyperbus_ops *ops;
0079 };
0080
0081 /**
0082  * hyperbus_register_device - probe and register a HyperBus slave memory device
0083  * @hbdev: hyperbus_device struct with dev, np and ctlr field populated
0084  *
0085  * Return: 0 for success, others for failure.
0086  */
0087 int hyperbus_register_device(struct hyperbus_device *hbdev);
0088
0089 /**
0090  * hyperbus_unregister_device - deregister HyperBus slave memory device
0091  * @hbdev: hyperbus_device to be unregistered
0092  */
0093 void hyperbus_unregister_device(struct hyperbus_device *hbdev);
0094
0095 #endif /* __LINUX_MTD_HYPERBUS_H__ */