include/linux/usb/ljca.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (c) 2023, Intel Corporation. All rights reserved.
   4  */
   5 #ifndef _LINUX_USB_LJCA_H_
   6 #define _LINUX_USB_LJCA_H_
   7
   8 #include <linux/auxiliary_bus.h>
   9 #include <linux/list.h>
  10 #include <linux/spinlock.h>
  11 #include <linux/types.h>
  12
  13 #define LJCA_MAX_GPIO_NUM 64
  14
  15 #define auxiliary_dev_to_ljca_client(auxiliary_dev)                     \
  16                 container_of(auxiliary_dev, struct ljca_client, auxdev)
  17
  18 struct ljca_adapter;
  19
  20 /**
  21  * typedef ljca_event_cb_t - event callback function signature
  22  *
  23  * @context: the execution context of who registered this callback
  24  * @cmd: the command from device for this event
  25  * @evt_data: the event data payload
  26  * @len: the event data payload length
  27  *
  28  * The callback function is called in interrupt context and the data payload is
  29  * only valid during the call. If the user needs later access of the data, it
  30  * must copy it.
  31  */
  32 typedef void (*ljca_event_cb_t)(void *context, u8 cmd, const void *evt_data, int len);
  33
  34 /**
  35  * struct ljca_client - represent a ljca client device
  36  *
  37  * @type: ljca client type
  38  * @id: ljca client id within same client type
  39  * @link: ljca client on the same ljca adapter
  40  * @auxdev: auxiliary device object
  41  * @adapter: ljca adapter the ljca client sit on
  42  * @context: the execution context of the event callback
  43  * @event_cb: ljca client driver register this callback to get
  44  *      firmware asynchronous rx buffer pending notifications
  45  * @event_cb_lock: spinlock to protect event callback
  46  */
  47 struct ljca_client {
  48         u8 type;
  49         u8 id;
  50         struct list_head link;
  51         struct auxiliary_device auxdev;
  52         struct ljca_adapter *adapter;
  53
  54         void *context;
  55         ljca_event_cb_t event_cb;
  56         /* lock to protect event_cb */
  57         spinlock_t event_cb_lock;
  58 };
  59
  60 /**
  61  * struct ljca_gpio_info - ljca gpio client device info
  62  *
  63  * @num: ljca gpio client device pin number
  64  * @valid_pin_map: ljca gpio client device valid pin mapping
  65  */
  66 struct ljca_gpio_info {
  67         unsigned int num;
  68         DECLARE_BITMAP(valid_pin_map, LJCA_MAX_GPIO_NUM);
  69 };
  70
  71 /**
  72  * struct ljca_i2c_info - ljca i2c client device info
  73  *
  74  * @id: ljca i2c client device identification number
  75  * @capacity: ljca i2c client device capacity
  76  * @intr_pin: ljca i2c client device interrupt pin number if exists
  77  */
  78 struct ljca_i2c_info {
  79         u8 id;
  80         u8 capacity;
  81         u8 intr_pin;
  82 };
  83
  84 /**
  85  * struct ljca_spi_info - ljca spi client device info
  86  *
  87  * @id: ljca spi client device identification number
  88  * @capacity: ljca spi client device capacity
  89  */
  90 struct ljca_spi_info {
  91         u8 id;
  92         u8 capacity;
  93 };
  94
  95 /**
  96  * ljca_register_event_cb - register a callback function to receive events
  97  *
  98  * @client: ljca client device
  99  * @event_cb: callback function
 100  * @context: execution context of event callback
 101  *
 102  * Return: 0 in case of success, negative value in case of error
 103  */
 104 int ljca_register_event_cb(struct ljca_client *client, ljca_event_cb_t event_cb, void *context);
 105
 106 /**
 107  * ljca_unregister_event_cb - unregister the callback function for an event
 108  *
 109  * @client: ljca client device
 110  */
 111 void ljca_unregister_event_cb(struct ljca_client *client);
 112
 113 /**
 114  * ljca_transfer - issue a LJCA command and wait for a response
 115  *
 116  * @client: ljca client device
 117  * @cmd: the command to be sent to the device
 118  * @obuf: the buffer to be sent to the device; it can be NULL if the user
 119  *      doesn't need to transmit data with this command
 120  * @obuf_len: the size of the buffer to be sent to the device; it should
 121  *      be 0 when obuf is NULL
 122  * @ibuf: any data associated with the response will be copied here; it can be
 123  *      NULL if the user doesn't need the response data
 124  * @ibuf_len: must be initialized to the input buffer size
 125  *
 126  * Return: the actual length of response data for success, negative value for errors
 127  */
 128 int ljca_transfer(struct ljca_client *client, u8 cmd, const u8 *obuf,
 129                   u8 obuf_len, u8 *ibuf, u8 ibuf_len);
 130
 131 /**
 132  * ljca_transfer_noack - issue a LJCA command without a response
 133  *
 134  * @client: ljca client device
 135  * @cmd: the command to be sent to the device
 136  * @obuf: the buffer to be sent to the device; it can be NULL if the user
 137  *      doesn't need to transmit data with this command
 138  * @obuf_len: the size of the buffer to be sent to the device
 139  *
 140  * Return: 0 for success, negative value for errors
 141  */
 142 int ljca_transfer_noack(struct ljca_client *client, u8 cmd, const u8 *obuf,
 143                         u8 obuf_len);
 144
 145 #endif