include/linux/slimbus.h

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (c) 2011-2017, The Linux Foundation
   4  */
   5
   6 #ifndef _LINUX_SLIMBUS_H
   7 #define _LINUX_SLIMBUS_H
   8 #include <linux/device.h>
   9 #include <linux/module.h>
  10 #include <linux/completion.h>
  11 #include <linux/mod_devicetable.h>
  12
  13 extern struct bus_type slimbus_bus;
  14
  15 /**
  16  * struct slim_eaddr - Enumeration address for a SLIMbus device
  17  * @manf_id: Manufacturer Id for the device
  18  * @prod_code: Product code
  19  * @dev_index: Device index
  20  * @instance: Instance value
  21  */
  22 struct slim_eaddr {
  23         u16 manf_id;
  24         u16 prod_code;
  25         u8 dev_index;
  26         u8 instance;
  27 } __packed;
  28
  29 /**
  30  * enum slim_device_status - slim device status
  31  * @SLIM_DEVICE_STATUS_DOWN: Slim device is absent or not reported yet.
  32  * @SLIM_DEVICE_STATUS_UP: Slim device is announced on the bus.
  33  * @SLIM_DEVICE_STATUS_RESERVED: Reserved for future use.
  34  */
  35 enum slim_device_status {
  36         SLIM_DEVICE_STATUS_DOWN = 0,
  37         SLIM_DEVICE_STATUS_UP,
  38         SLIM_DEVICE_STATUS_RESERVED,
  39 };
  40
  41 struct slim_controller;
  42
  43 /**
  44  * struct slim_device - Slim device handle.
  45  * @dev: Driver model representation of the device.
  46  * @e_addr: Enumeration address of this device.
  47  * @status: slim device status
  48  * @ctrl: slim controller instance.
  49  * @laddr: 1-byte Logical address of this device.
  50  * @is_laddr_valid: indicates if the laddr is valid or not
  51  *
  52  * This is the client/device handle returned when a SLIMbus
  53  * device is registered with a controller.
  54  * Pointer to this structure is used by client-driver as a handle.
  55  */
  56 struct slim_device {
  57         struct device           dev;
  58         struct slim_eaddr       e_addr;
  59         struct slim_controller  *ctrl;
  60         enum slim_device_status status;
  61         u8                      laddr;
  62         bool                    is_laddr_valid;
  63 };
  64
  65 #define to_slim_device(d) container_of(d, struct slim_device, dev)
  66
  67 /**
  68  * struct slim_driver - SLIMbus 'generic device' (slave) device driver
  69  *                              (similar to 'spi_device' on SPI)
  70  * @probe: Binds this driver to a SLIMbus device.
  71  * @remove: Unbinds this driver from the SLIMbus device.
  72  * @shutdown: Standard shutdown callback used during powerdown/halt.
  73  * @device_status: This callback is called when
  74  *      - The device reports present and gets a laddr assigned
  75  *      - The device reports absent, or the bus goes down.
  76  * @driver: SLIMbus device drivers should initialize name and owner field of
  77  *          this structure
  78  * @id_table: List of SLIMbus devices supported by this driver
  79  */
  80
  81 struct slim_driver {
  82         int     (*probe)(struct slim_device *sl);
  83         void    (*remove)(struct slim_device *sl);
  84         void    (*shutdown)(struct slim_device *sl);
  85         int     (*device_status)(struct slim_device *sl,
  86                                  enum slim_device_status s);
  87         struct device_driver            driver;
  88         const struct slim_device_id     *id_table;
  89 };
  90 #define to_slim_driver(d) container_of(d, struct slim_driver, driver)
  91
  92 /**
  93  * struct slim_val_inf - Slimbus value or information element
  94  * @start_offset: Specifies starting offset in information/value element map
  95  * @rbuf: buffer to read the values
  96  * @wbuf: buffer to write
  97  * @num_bytes: upto 16. This ensures that the message will fit the slicesize
  98  *              per SLIMbus spec
  99  * @comp: completion for asynchronous operations, valid only if TID is
 100  *        required for transaction, like REQUEST operations.
 101  *        Rest of the transactions are synchronous anyway.
 102  */
 103 struct slim_val_inf {
 104         u16                     start_offset;
 105         u8                      num_bytes;
 106         u8                      *rbuf;
 107         const u8                *wbuf;
 108         struct  completion      *comp;
 109 };
 110
 111 /*
 112  * use a macro to avoid include chaining to get THIS_MODULE
 113  */
 114 #define slim_driver_register(drv) \
 115         __slim_driver_register(drv, THIS_MODULE)
 116 int __slim_driver_register(struct slim_driver *drv, struct module *owner);
 117 void slim_driver_unregister(struct slim_driver *drv);
 118
 119 /**
 120  * module_slim_driver() - Helper macro for registering a SLIMbus driver
 121  * @__slim_driver: slimbus_driver struct
 122  *
 123  * Helper macro for SLIMbus drivers which do not do anything special in module
 124  * init/exit. This eliminates a lot of boilerplate. Each module may only
 125  * use this macro once, and calling it replaces module_init() and module_exit()
 126  */
 127 #define module_slim_driver(__slim_driver) \
 128         module_driver(__slim_driver, slim_driver_register, \
 129                         slim_driver_unregister)
 130
 131 static inline void *slim_get_devicedata(const struct slim_device *dev)
 132 {
 133         return dev_get_drvdata(&dev->dev);
 134 }
 135
 136 static inline void slim_set_devicedata(struct slim_device *dev, void *data)
 137 {
 138         dev_set_drvdata(&dev->dev, data);
 139 }
 140
 141 struct slim_device *slim_get_device(struct slim_controller *ctrl,
 142                                     struct slim_eaddr *e_addr);
 143 int slim_get_logical_addr(struct slim_device *sbdev);
 144
 145 /* Information Element management messages */
 146 #define SLIM_MSG_MC_REQUEST_INFORMATION          0x20
 147 #define SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION    0x21
 148 #define SLIM_MSG_MC_REPLY_INFORMATION            0x24
 149 #define SLIM_MSG_MC_CLEAR_INFORMATION            0x28
 150 #define SLIM_MSG_MC_REPORT_INFORMATION           0x29
 151
 152 /* Value Element management messages */
 153 #define SLIM_MSG_MC_REQUEST_VALUE                0x60
 154 #define SLIM_MSG_MC_REQUEST_CHANGE_VALUE         0x61
 155 #define SLIM_MSG_MC_REPLY_VALUE                  0x64
 156 #define SLIM_MSG_MC_CHANGE_VALUE                 0x68
 157
 158 int slim_xfer_msg(struct slim_device *sbdev, struct slim_val_inf *msg,
 159                   u8 mc);
 160 int slim_readb(struct slim_device *sdev, u32 addr);
 161 int slim_writeb(struct slim_device *sdev, u32 addr, u8 value);
 162 int slim_read(struct slim_device *sdev, u32 addr, size_t count, u8 *val);
 163 int slim_write(struct slim_device *sdev, u32 addr, size_t count, u8 *val);
 164 #endif /* _LINUX_SLIMBUS_H */