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  * @instance: Instance value
  18  * @dev_index: Device index
  19  * @prod_code: Product code
  20  * @manf_id: Manufacturer Id for the device
  21  */
  22 struct slim_eaddr {
  23         u8 instance;
  24         u8 dev_index;
  25         u16 prod_code;
  26         u16 manf_id;
  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  * @stream_list: List of streams on this device
  52  * @stream_list_lock: lock to protect the stream list
  53  *
  54  * This is the client/device handle returned when a SLIMbus
  55  * device is registered with a controller.
  56  * Pointer to this structure is used by client-driver as a handle.
  57  */
  58 struct slim_device {
  59         struct device           dev;
  60         struct slim_eaddr       e_addr;
  61         struct slim_controller  *ctrl;
  62         enum slim_device_status status;
  63         u8                      laddr;
  64         bool                    is_laddr_valid;
  65         struct list_head        stream_list;
  66         spinlock_t stream_list_lock;
  67 };
  68
  69 #define to_slim_device(d) container_of(d, struct slim_device, dev)
  70
  71 /**
  72  * struct slim_driver - SLIMbus 'generic device' (slave) device driver
  73  *                              (similar to 'spi_device' on SPI)
  74  * @probe: Binds this driver to a SLIMbus device.
  75  * @remove: Unbinds this driver from the SLIMbus device.
  76  * @shutdown: Standard shutdown callback used during powerdown/halt.
  77  * @device_status: This callback is called when
  78  *      - The device reports present and gets a laddr assigned
  79  *      - The device reports absent, or the bus goes down.
  80  * @driver: SLIMbus device drivers should initialize name and owner field of
  81  *          this structure
  82  * @id_table: List of SLIMbus devices supported by this driver
  83  */
  84
  85 struct slim_driver {
  86         int     (*probe)(struct slim_device *sl);
  87         void    (*remove)(struct slim_device *sl);
  88         void    (*shutdown)(struct slim_device *sl);
  89         int     (*device_status)(struct slim_device *sl,
  90                                  enum slim_device_status s);
  91         struct device_driver            driver;
  92         const struct slim_device_id     *id_table;
  93 };
  94 #define to_slim_driver(d) container_of(d, struct slim_driver, driver)
  95
  96 /**
  97  * struct slim_val_inf - Slimbus value or information element
  98  * @start_offset: Specifies starting offset in information/value element map
  99  * @rbuf: buffer to read the values
 100  * @wbuf: buffer to write
 101  * @num_bytes: upto 16. This ensures that the message will fit the slicesize
 102  *              per SLIMbus spec
 103  * @comp: completion for asynchronous operations, valid only if TID is
 104  *        required for transaction, like REQUEST operations.
 105  *        Rest of the transactions are synchronous anyway.
 106  */
 107 struct slim_val_inf {
 108         u16                     start_offset;
 109         u8                      num_bytes;
 110         u8                      *rbuf;
 111         const u8                *wbuf;
 112         struct  completion      *comp;
 113 };
 114
 115 #define SLIM_DEVICE_MAX_CHANNELS        256
 116 /* A SLIMBus Device may have frmo 0 to 31 Ports (inclusive) */
 117 #define SLIM_DEVICE_MAX_PORTS           32
 118
 119 /**
 120  * struct slim_stream_config - SLIMbus stream configuration
 121  *      Configuring a stream is done at hw_params or prepare call
 122  *      from audio drivers where they have all the required information
 123  *      regarding rate, number of channels and so on.
 124  *      There is a 1:1 mapping of channel and ports.
 125  *
 126  * @rate: data rate
 127  * @bps: bits per data sample
 128  * @ch_count: number of channels
 129  * @chs: pointer to list of channel numbers
 130  * @port_mask: port mask of ports to use for this stream
 131  * @direction: direction of the stream, SNDRV_PCM_STREAM_PLAYBACK
 132  *      or SNDRV_PCM_STREAM_CAPTURE.
 133  */
 134 struct slim_stream_config {
 135         unsigned int rate;
 136         unsigned int bps;
 137         /* MAX 256 channels */
 138         unsigned int ch_count;
 139         unsigned int *chs;
 140         /* Max 32 ports per device */
 141         unsigned long port_mask;
 142         int direction;
 143 };
 144
 145 /*
 146  * use a macro to avoid include chaining to get THIS_MODULE
 147  */
 148 #define slim_driver_register(drv) \
 149         __slim_driver_register(drv, THIS_MODULE)
 150 int __slim_driver_register(struct slim_driver *drv, struct module *owner);
 151 void slim_driver_unregister(struct slim_driver *drv);
 152
 153 /**
 154  * module_slim_driver() - Helper macro for registering a SLIMbus driver
 155  * @__slim_driver: slimbus_driver struct
 156  *
 157  * Helper macro for SLIMbus drivers which do not do anything special in module
 158  * init/exit. This eliminates a lot of boilerplate. Each module may only
 159  * use this macro once, and calling it replaces module_init() and module_exit()
 160  */
 161 #define module_slim_driver(__slim_driver) \
 162         module_driver(__slim_driver, slim_driver_register, \
 163                         slim_driver_unregister)
 164
 165 static inline void *slim_get_devicedata(const struct slim_device *dev)
 166 {
 167         return dev_get_drvdata(&dev->dev);
 168 }
 169
 170 static inline void slim_set_devicedata(struct slim_device *dev, void *data)
 171 {
 172         dev_set_drvdata(&dev->dev, data);
 173 }
 174
 175 struct slim_device *of_slim_get_device(struct slim_controller *ctrl,
 176                                        struct device_node *np);
 177 struct slim_device *slim_get_device(struct slim_controller *ctrl,
 178                                     struct slim_eaddr *e_addr);
 179 int slim_get_logical_addr(struct slim_device *sbdev);
 180
 181 /* Information Element management messages */
 182 #define SLIM_MSG_MC_REQUEST_INFORMATION          0x20
 183 #define SLIM_MSG_MC_REQUEST_CLEAR_INFORMATION    0x21
 184 #define SLIM_MSG_MC_REPLY_INFORMATION            0x24
 185 #define SLIM_MSG_MC_CLEAR_INFORMATION            0x28
 186 #define SLIM_MSG_MC_REPORT_INFORMATION           0x29
 187
 188 /* Value Element management messages */
 189 #define SLIM_MSG_MC_REQUEST_VALUE                0x60
 190 #define SLIM_MSG_MC_REQUEST_CHANGE_VALUE         0x61
 191 #define SLIM_MSG_MC_REPLY_VALUE                  0x64
 192 #define SLIM_MSG_MC_CHANGE_VALUE                 0x68
 193
 194 int slim_xfer_msg(struct slim_device *sbdev, struct slim_val_inf *msg,
 195                   u8 mc);
 196 int slim_readb(struct slim_device *sdev, u32 addr);
 197 int slim_writeb(struct slim_device *sdev, u32 addr, u8 value);
 198 int slim_read(struct slim_device *sdev, u32 addr, size_t count, u8 *val);
 199 int slim_write(struct slim_device *sdev, u32 addr, size_t count, u8 *val);
 200
 201 /* SLIMbus Stream apis */
 202 struct slim_stream_runtime;
 203 struct slim_stream_runtime *slim_stream_allocate(struct slim_device *dev,
 204                                                  const char *sname);
 205 int slim_stream_prepare(struct slim_stream_runtime *stream,
 206                         struct slim_stream_config *c);
 207 int slim_stream_enable(struct slim_stream_runtime *stream);
 208 int slim_stream_disable(struct slim_stream_runtime *stream);
 209 int slim_stream_unprepare(struct slim_stream_runtime *stream);
 210 int slim_stream_free(struct slim_stream_runtime *stream);
 211
 212 #endif /* _LINUX_SLIMBUS_H */