include/linux/mtd/hyperbus.h

   1 /* SPDX-License-Identifier: GPL-2.0
   2  *
   3  * Copyright (C) 2019 Texas Instruments Incorporated - https://www.ti.com/
   4  */
   5
   6 #ifndef __LINUX_MTD_HYPERBUS_H__
   7 #define __LINUX_MTD_HYPERBUS_H__
   8
   9 #include <linux/mtd/map.h>
  10
  11 /* HyperBus command bits */
  12 #define HYPERBUS_RW     0x80    /* R/W# */
  13 #define HYPERBUS_RW_WRITE 0
  14 #define HYPERBUS_RW_READ 0x80
  15 #define HYPERBUS_AS     0x40    /* Address Space */
  16 #define HYPERBUS_AS_MEM 0
  17 #define HYPERBUS_AS_REG 0x40
  18 #define HYPERBUS_BT     0x20    /* Burst Type */
  19 #define HYPERBUS_BT_WRAPPED 0
  20 #define HYPERBUS_BT_LINEAR 0x20
  21
  22 enum hyperbus_memtype {
  23         HYPERFLASH,
  24         HYPERRAM,
  25 };
  26
  27 /**
  28  * struct hyperbus_device - struct representing HyperBus slave device
  29  * @map: map_info struct for accessing MMIO HyperBus flash memory
  30  * @np: pointer to HyperBus slave device node
  31  * @mtd: pointer to MTD struct
  32  * @ctlr: pointer to HyperBus controller struct
  33  * @memtype: type of memory device: HyperFlash or HyperRAM
  34  * @priv: pointer to controller specific per device private data
  35  */
  36
  37 struct hyperbus_device {
  38         struct map_info map;
  39         struct device_node *np;
  40         struct mtd_info *mtd;
  41         struct hyperbus_ctlr *ctlr;
  42         enum hyperbus_memtype memtype;
  43         void *priv;
  44 };
  45
  46 /**
  47  * struct hyperbus_ops - struct representing custom HyperBus operations
  48  * @read16: read 16 bit of data from flash in a single burst. Used to read
  49  *          from non default address space, such as ID/CFI space
  50  * @write16: write 16 bit of data to flash in a single burst. Used to
  51  *           send cmd to flash or write single 16 bit word at a time.
  52  * @copy_from: copy data from flash memory
  53  * @copy_to: copy data to flash memory
  54  * @calibrate: calibrate HyperBus controller
  55  */
  56
  57 struct hyperbus_ops {
  58         u16 (*read16)(struct hyperbus_device *hbdev, unsigned long addr);
  59         void (*write16)(struct hyperbus_device *hbdev,
  60                         unsigned long addr, u16 val);
  61         void (*copy_from)(struct hyperbus_device *hbdev, void *to,
  62                           unsigned long from, ssize_t len);
  63         void (*copy_to)(struct hyperbus_device *dev, unsigned long to,
  64                         const void *from, ssize_t len);
  65         int (*calibrate)(struct hyperbus_device *dev);
  66 };
  67
  68 /**
  69  * struct hyperbus_ctlr - struct representing HyperBus controller
  70  * @dev: pointer to HyperBus controller device
  71  * @calibrated: flag to indicate ctlr calibration sequence is complete
  72  * @ops: HyperBus controller ops
  73  */
  74 struct hyperbus_ctlr {
  75         struct device *dev;
  76         bool calibrated;
  77
  78         const struct hyperbus_ops *ops;
  79 };
  80
  81 /**
  82  * hyperbus_register_device - probe and register a HyperBus slave memory device
  83  * @hbdev: hyperbus_device struct with dev, np and ctlr field populated
  84  *
  85  * Return: 0 for success, others for failure.
  86  */
  87 int hyperbus_register_device(struct hyperbus_device *hbdev);
  88
  89 /**
  90  * hyperbus_unregister_device - deregister HyperBus slave memory device
  91  * @hbdev: hyperbus_device to be unregistered
  92  */
  93 void hyperbus_unregister_device(struct hyperbus_device *hbdev);
  94
  95 #endif /* __LINUX_MTD_HYPERBUS_H__ */