1 /*
2 * Copyright (c) 2020 Libre Solar Technologies GmbH
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 /**
8 * @file
9 * @brief DAC public API header file.
10 */
11
12 #ifndef ZEPHYR_INCLUDE_DRIVERS_DAC_H_
13 #define ZEPHYR_INCLUDE_DRIVERS_DAC_H_
14
15 #include <device.h>
16
17 #ifdef __cplusplus
18 extern "C" {
19 #endif
20
21 /**
22 * @brief DAC driver APIs
23 * @defgroup dac_interface DAC driver APIs
24 * @ingroup io_interfaces
25 * @{
26 */
27
28 /**
29 * @struct dac_channel_cfg
30 * @brief Structure for specifying the configuration of a DAC channel.
31 *
32 * @param channel_id Channel identifier of the DAC that should be configured.
33 * @param resolution Desired resolution of the DAC (depends on device
34 * capabilities).
35 */
36 struct dac_channel_cfg {
37 uint8_t channel_id;
38 uint8_t resolution;
39 };
40
41 /**
42 * @cond INTERNAL_HIDDEN
43 *
44 * For internal use only, skip these in public documentation.
45 */
46
47 /*
48 * Type definition of DAC API function for configuring a channel.
49 * See dac_channel_setup() for argument descriptions.
50 */
51 typedef int (*dac_api_channel_setup)(const struct device *dev,
52 const struct dac_channel_cfg *channel_cfg);
53
54 /*
55 * Type definition of DAC API function for setting a write request.
56 * See dac_write_value() for argument descriptions.
57 */
58 typedef int (*dac_api_write_value)(const struct device *dev,
59 uint8_t channel, uint32_t value);
60
61 /*
62 * DAC driver API
63 *
64 * This is the mandatory API any DAC driver needs to expose.
65 */
66 __subsystem struct dac_driver_api {
67 dac_api_channel_setup channel_setup;
68 dac_api_write_value write_value;
69 };
70
71 /**
72 * @endcond
73 */
74
75 /**
76 * @brief Configure a DAC channel.
77 *
78 * It is required to call this function and configure each channel before it is
79 * selected for a write request.
80 *
81 * @param dev Pointer to the device structure for the driver instance.
82 * @param channel_cfg Channel configuration.
83 *
84 * @retval 0 On success.
85 * @retval -EINVAL If a parameter with an invalid value has been provided.
86 * @retval -ENOTSUP If the requested resolution is not supported.
87 */
88 __syscall int dac_channel_setup(const struct device *dev,
89 const struct dac_channel_cfg *channel_cfg);
90
z_impl_dac_channel_setup(const struct device * dev,const struct dac_channel_cfg * channel_cfg)91 static inline int z_impl_dac_channel_setup(const struct device *dev,
92 const struct dac_channel_cfg *channel_cfg)
93 {
94 const struct dac_driver_api *api =
95 (const struct dac_driver_api *)dev->api;
96
97 return api->channel_setup(dev, channel_cfg);
98 }
99
100 /**
101 * @brief Write a single value to a DAC channel
102 *
103 * @param dev Pointer to the device structure for the driver instance.
104 * @param channel Number of the channel to be used.
105 * @param value Data to be written to DAC output registers.
106 *
107 * @retval 0 On success.
108 * @retval -EINVAL If a parameter with an invalid value has been provided.
109 */
110 __syscall int dac_write_value(const struct device *dev, uint8_t channel,
111 uint32_t value);
112
z_impl_dac_write_value(const struct device * dev,uint8_t channel,uint32_t value)113 static inline int z_impl_dac_write_value(const struct device *dev,
114 uint8_t channel, uint32_t value)
115 {
116 const struct dac_driver_api *api =
117 (const struct dac_driver_api *)dev->api;
118
119 return api->write_value(dev, channel, value);
120 }
121
122 /**
123 * @}
124 */
125
126 #ifdef __cplusplus
127 }
128 #endif
129
130 #include <syscalls/dac.h>
131
132 #endif /* ZEPHYR_INCLUDE_DRIVERS_DAC_H_ */
133
