1 /**
2  * \file
3  *
4  * \brief SAM AC - Analog Comparator Callback Driver
5  *
6  * Copyright (C) 2013-2015 Atmel Corporation. All rights reserved.
7  *
8  * \asf_license_start
9  *
10  * \page License
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions are met:
14  *
15  * 1. Redistributions of source code must retain the above copyright notice,
16  *    this list of conditions and the following disclaimer.
17  *
18  * 2. Redistributions in binary form must reproduce the above copyright notice,
19  *    this list of conditions and the following disclaimer in the documentation
20  *    and/or other materials provided with the distribution.
21  *
22  * 3. The name of Atmel may not be used to endorse or promote products derived
23  *    from this software without specific prior written permission.
24  *
25  * 4. This software may only be redistributed and used in connection with an
26  *    Atmel microcontroller product.
27  *
28  * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
29  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
30  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
31  * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
32  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
36  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
37  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38  * POSSIBILITY OF SUCH DAMAGE.
39  *
40  * \asf_license_stop
41  *
42  */
43 /*
44  * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
45  */
46 
47 #include "ac_callback.h"
48 
49 struct ac_module *_ac_instance[AC_INST_NUM];
50 
51 void _ac_interrupt_handler(const uint32_t instance_index);
52 
53 /**
54  * \brief Registers a callback.
55  *
56  * Registers a callback function which is implemented by the user.
57  *
58  * \note The callback must be enabled by \ref ac_enable_callback,
59  * in order for the interrupt handler to call it when the conditions for the
60  * callback type is met.
61  *
62  * \param[in]     module      Pointer to software instance struct
63  * \param[in]     callback_func Pointer to callback function
64  * \param[in]     callback_type Callback type given by an enum
65  *
66  * \retval STATUS_OK  The function exited successfully
67  */
ac_register_callback(struct ac_module * const module,ac_callback_t callback_func,const enum ac_callback callback_type)68 enum status_code ac_register_callback(
69 		struct ac_module *const module,
70 		ac_callback_t callback_func,
71 		const enum ac_callback callback_type)
72 {
73 	/* Sanity check arguments */
74 	Assert(module);
75 	Assert(callback_func);
76 
77 	/* Register callback function */
78 	module->callback[callback_type] = callback_func;
79 
80 	/* Set software flag for callback */
81 	module->register_callback_mask |= (1 << callback_type);
82 
83 	return STATUS_OK;
84 }
85 
86 /**
87  * \brief Unregisters a callback.
88  *
89  * Unregisters a callback function implemented by the user.
90  *
91  * \param[in]     module Pointer to AC software instance struct
92  * \param[in]     callback_type Callback type given by an enum
93  *
94  * \retval STATUS_OK  The function exited successfully
95  */
ac_unregister_callback(struct ac_module * const module,const enum ac_callback callback_type)96 enum status_code ac_unregister_callback(
97 		struct ac_module *const module,
98 		const enum ac_callback callback_type)
99 {
100 	/* Sanity check arguments */
101 	Assert(module);
102 	/* Unregister callback function */
103 	module->callback[callback_type] = NULL;
104 
105 	/* Clear software flag for callback */
106 	module->register_callback_mask &= ~(1 << callback_type);
107 
108 	return STATUS_OK;
109 }
110 
111 /**
112  * \internal ISR handler for AC
113  */
114 #if (AC_INST_NUM == 1)
AC_Handler(void)115 void AC_Handler(void)
116 {
117 	_ac_interrupt_handler(0);
118 }
119 #elif (AC_INST_NUM == 2)
AC_Handler(void)120 void AC_Handler(void)
121 {
122 	_ac_interrupt_handler(0);
123 }
124 
AC1_Handler(void)125 void AC1_Handler(void)
126 {
127 	_ac_interrupt_handler(1);
128 }
129 #else
130 #  error This driver is not support more than three AC instances.
131 #endif
132 
133 /**
134  * \brief Interrupt Handler for AC module.
135  *
136  * Handles interrupts as they occur, it will run the callback functions
137  * that are registered and enabled.
138  *
139  * \param [in] instance_index  Default value 0
140  */
_ac_interrupt_handler(const uint32_t instance_index)141 void _ac_interrupt_handler(const uint32_t instance_index)
142 {
143 	/* Temporary variable */
144 	uint8_t interrupt_and_callback_status_mask;
145 
146 	/* Get device instance from the look-up table */
147 
148 	struct ac_module *module = _ac_instance[instance_index];
149 
150 	/* Read and mask interrupt flag register */
151 	interrupt_and_callback_status_mask =
152 			_ac_instance[instance_index]->hw->INTFLAG.reg &
153 			(module->register_callback_mask & module->enable_callback_mask);
154 
155 	/* Check if comparator channel 0 needs to be serviced */
156 	if (interrupt_and_callback_status_mask & AC_INTFLAG_COMP0) {
157 		/* Invoke registered and enabled callback function */
158 		(module->callback[AC_CALLBACK_COMPARATOR_0])(module);
159 		/* Clear interrupt flag */
160 		module->hw->INTFLAG.reg = AC_INTFLAG_COMP0;
161 	}
162 
163 	/* Check if comparator channel 1 needs to be serviced */
164 	if (interrupt_and_callback_status_mask & AC_INTFLAG_COMP1) {
165 		/* Invoke registered and enabled callback function */
166 		(module->callback[AC_CALLBACK_COMPARATOR_1])(module);
167 		/* Clear interrupt flag */
168 		module->hw->INTFLAG.reg = AC_INTFLAG_COMP1;
169 	}
170 
171 	/* Check if window 0 needs to be serviced */
172 	if (interrupt_and_callback_status_mask & AC_INTFLAG_WIN0) {
173 		/* Invoke registered and enabled callback function */
174 		(module->callback[AC_CALLBACK_WINDOW_0])(module);
175 		/* Clear interrupt flag */
176 		module->hw->INTFLAG.reg = AC_INTFLAG_WIN0;
177 	}
178 
179 #if (AC_NUM_CMP > 2)
180 		/* Check if comparator channel 2 needs to be serviced */
181 	if (interrupt_and_callback_status_mask & AC_INTFLAG_COMP2) {
182 		/* Invoke registered and enabled callback function */
183 		(module->callback[AC_CALLBACK_COMPARATOR_2])(module);
184 		/* Clear interrupt flag */
185 		module->hw->INTFLAG.reg = AC_INTFLAG_COMP2;
186 	}
187 
188 	/* Check if comparator channel 3 needs to be serviced */
189 	if (interrupt_and_callback_status_mask & AC_INTFLAG_COMP3) {
190 		/* Invoke registered and enabled callback function */
191 		(module->callback[AC_CALLBACK_COMPARATOR_3])(module);
192 		/* Clear interrupt flag */
193 		module->hw->INTFLAG.reg = AC_INTFLAG_COMP3;
194 	}
195 
196 #  if !(SAMC20)
197 		/* Check if window 1 needs to be serviced */
198 	if (interrupt_and_callback_status_mask & AC_INTFLAG_WIN1) {
199 		/* Invoke registered and enabled callback function */
200 		(module->callback[AC_CALLBACK_WINDOW_1])(module);
201 		/* Clear interrupt flag */
202 		module->hw->INTFLAG.reg = AC_INTFLAG_WIN1;
203 	}
204 #  endif
205 #endif /* (AC_NUM_CMP > 2) */
206 }
207