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 <zephyr/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 * @brief Structure for specifying the configuration of a DAC channel.
30 */
31 struct dac_channel_cfg {
32 /** Channel identifier of the DAC that should be configured. */
33 uint8_t channel_id;
34 /** Desired resolution of the DAC (depends on device capabilities). */
35 uint8_t resolution;
36 /** Enable output buffer for this channel.
37 * This is relevant for instance if the output is directly connected to the load,
38 * without an amplifierin between. The actual details on this are hardware dependent.
39 */
40 bool buffered;
41 };
42
43 /**
44 * @cond INTERNAL_HIDDEN
45 *
46 * For internal use only, skip these in public documentation.
47 */
48
49 /*
50 * Type definition of DAC API function for configuring a channel.
51 * See dac_channel_setup() for argument descriptions.
52 */
53 typedef int (*dac_api_channel_setup)(const struct device *dev,
54 const struct dac_channel_cfg *channel_cfg);
55
56 /*
57 * Type definition of DAC API function for setting a write request.
58 * See dac_write_value() for argument descriptions.
59 */
60 typedef int (*dac_api_write_value)(const struct device *dev,
61 uint8_t channel, uint32_t value);
62
63 /*
64 * DAC driver API
65 *
66 * This is the mandatory API any DAC driver needs to expose.
67 */
68 __subsystem struct dac_driver_api {
69 dac_api_channel_setup channel_setup;
70 dac_api_write_value write_value;
71 };
72
73 /**
74 * @endcond
75 */
76
77 /**
78 * @brief Configure a DAC channel.
79 *
80 * It is required to call this function and configure each channel before it is
81 * selected for a write request.
82 *
83 * @param dev Pointer to the device structure for the driver instance.
84 * @param channel_cfg Channel configuration.
85 *
86 * @retval 0 On success.
87 * @retval -EINVAL If a parameter with an invalid value has been provided.
88 * @retval -ENOTSUP If the requested resolution is not supported.
89 */
90 __syscall int dac_channel_setup(const struct device *dev,
91 const struct dac_channel_cfg *channel_cfg);
92
z_impl_dac_channel_setup(const struct device * dev,const struct dac_channel_cfg * channel_cfg)93 static inline int z_impl_dac_channel_setup(const struct device *dev,
94 const struct dac_channel_cfg *channel_cfg)
95 {
96 const struct dac_driver_api *api =
97 (const struct dac_driver_api *)dev->api;
98
99 return api->channel_setup(dev, channel_cfg);
100 }
101
102 /**
103 * @brief Write a single value to a DAC channel
104 *
105 * @param dev Pointer to the device structure for the driver instance.
106 * @param channel Number of the channel to be used.
107 * @param value Data to be written to DAC output registers.
108 *
109 * @retval 0 On success.
110 * @retval -EINVAL If a parameter with an invalid value has been provided.
111 */
112 __syscall int dac_write_value(const struct device *dev, uint8_t channel,
113 uint32_t value);
114
z_impl_dac_write_value(const struct device * dev,uint8_t channel,uint32_t value)115 static inline int z_impl_dac_write_value(const struct device *dev,
116 uint8_t channel, uint32_t value)
117 {
118 const struct dac_driver_api *api =
119 (const struct dac_driver_api *)dev->api;
120
121 return api->write_value(dev, channel, value);
122 }
123
124 /**
125 * @}
126 */
127
128 #ifdef __cplusplus
129 }
130 #endif
131
132 #include <syscalls/dac.h>
133
134 #endif /* ZEPHYR_INCLUDE_DRIVERS_DAC_H_ */
135
