summaryrefslogtreecommitdiffstats
path: root/platforms/chibios/drivers/ws2812_pwm.c
blob: 19ea3cfe8ac6ccfd5ddac58aaea981b9a602b4df (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
#include "ws2812.h"
#include "quantum.h"
#include <hal.h>

/* Adapted from https://github.com/joewa/WS2812-LED-Driver_ChibiOS/ */

#ifdef RGBW
#    define WS2812_CHANNELS 4
#else
#    define WS2812_CHANNELS 3
#endif

#ifndef WS2812_PWM_DRIVER
#    define WS2812_PWM_DRIVER PWMD2  // TIMx
#endif
#ifndef WS2812_PWM_CHANNEL
#    define WS2812_PWM_CHANNEL 2  // Channel
#endif
#ifndef WS2812_PWM_PAL_MODE
#    define WS2812_PWM_PAL_MODE 2  // DI Pin's alternate function value
#endif
#ifndef WS2812_DMA_STREAM
#    define WS2812_DMA_STREAM STM32_DMA1_STREAM2  // DMA Stream for TIMx_UP
#endif
#ifndef WS2812_DMA_CHANNEL
#    define WS2812_DMA_CHANNEL 2  // DMA Channel for TIMx_UP
#endif
#if (STM32_DMA_SUPPORTS_DMAMUX == TRUE) && !defined(WS2812_DMAMUX_ID)
#    error "please consult your MCU's datasheet and specify in your config.h: #define WS2812_DMAMUX_ID STM32_DMAMUX1_TIM?_UP"
#endif

#ifndef WS2812_PWM_COMPLEMENTARY_OUTPUT
#    define WS2812_PWM_OUTPUT_MODE PWM_OUTPUT_ACTIVE_HIGH
#else
#    if !STM32_PWM_USE_ADVANCED
#        error "WS2812_PWM_COMPLEMENTARY_OUTPUT requires STM32_PWM_USE_ADVANCED == TRUE"
#    endif
#    define WS2812_PWM_OUTPUT_MODE PWM_COMPLEMENTARY_OUTPUT_ACTIVE_HIGH
#endif

// Push Pull or Open Drain Configuration
// Default Push Pull
#ifndef WS2812_EXTERNAL_PULLUP
#    if defined(USE_GPIOV1)
#        define WS2812_OUTPUT_MODE PAL_MODE_ALTERNATE_PUSHPULL
#    else
#        define WS2812_OUTPUT_MODE PAL_MODE_ALTERNATE(WS2812_PWM_PAL_MODE) | PAL_OUTPUT_TYPE_PUSHPULL | PAL_OUTPUT_SPEED_HIGHEST | PAL_PUPDR_FLOATING
#    endif
#else
#    if defined(USE_GPIOV1)
#        define WS2812_OUTPUT_MODE PAL_MODE_ALTERNATE_OPENDRAIN
#    else
#        define WS2812_OUTPUT_MODE PAL_MODE_ALTERNATE(WS2812_PWM_PAL_MODE) | PAL_OUTPUT_TYPE_OPENDRAIN | PAL_OUTPUT_SPEED_HIGHEST | PAL_PUPDR_FLOATING
#    endif
#endif

#ifndef WS2812_PWM_TARGET_PERIOD
//#    define WS2812_PWM_TARGET_PERIOD 800000 // Original code is 800k...?
#    define WS2812_PWM_TARGET_PERIOD 80000  // TODO: work out why 10x less on f303/f4x1
#endif

/* --- PRIVATE CONSTANTS ---------------------------------------------------- */

#define WS2812_PWM_FREQUENCY (CPU_CLOCK / 2)                                /**< Clock frequency of PWM, must be valid with respect to system clock! */
#define WS2812_PWM_PERIOD (WS2812_PWM_FREQUENCY / WS2812_PWM_TARGET_PERIOD) /**< Clock period in ticks. 1 / 800kHz = 1.25 uS (as per datasheet) */

/**
 * @brief   Number of bit-periods to hold the data line low at the end of a frame
 *
 * The reset period for each frame is defined in WS2812_TRST_US.
 * Calculate the number of zeroes to add at the end assuming 1.25 uS/bit:
 */
#define WS2812_COLOR_BITS (WS2812_CHANNELS * 8)
#define WS2812_RESET_BIT_N (1000 * WS2812_TRST_US / WS2812_TIMING)
#define WS2812_COLOR_BIT_N (RGBLED_NUM * WS2812_COLOR_BITS)    /**< Number of data bits */
#define WS2812_BIT_N (WS2812_COLOR_BIT_N + WS2812_RESET_BIT_N) /**< Total number of bits in a frame */

/**
 * @brief   High period for a zero, in ticks
 *
 * Per the datasheet:
 * WS2812:
 * - T0H: 200 nS to 500 nS, inclusive
 * - T0L: 650 nS to 950 nS, inclusive
 * WS2812B:
 * - T0H: 200 nS to 500 nS, inclusive
 * - T0L: 750 nS to 1050 nS, inclusive
 *
 * The duty cycle is calculated for a high period of 350 nS.
 */
#define WS2812_DUTYCYCLE_0 (WS2812_PWM_FREQUENCY / (1000000000 / 350))

/**
 * @brief   High period for a one, in ticks
 *
 * Per the datasheet:
 * WS2812:
 * - T1H: 550 nS to 850 nS, inclusive
 * - T1L: 450 nS to 750 nS, inclusive
 * WS2812B:
 * - T1H: 750 nS to 1050 nS, inclusive
 * - T1L: 200 nS to 500 nS, inclusive
 *
 * The duty cycle is calculated for a high period of 800 nS.
 * This is in the middle of the specifications of the WS2812 and WS2812B.
 */
#define WS2812_DUTYCYCLE_1 (WS2812_PWM_FREQUENCY / (1000000000 / 800))

/* --- PRIVATE MACROS ------------------------------------------------------- */

/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given bit
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] byte:                 The byte number [0, 2]
 * @param[in] bit:                  The bit number [0, 7]
 *
 * @return                          The bit index
 */
#define WS2812_BIT(led, byte, bit) (WS2812_COLOR_BITS * (led) + 8 * (byte) + (7 - (bit)))

#if (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_GRB)
/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given red bit
 *
 * @note    The red byte is the middle byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit number [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_RED_BIT(led, bit) WS2812_BIT((led), 1, (bit))

/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given green bit
 *
 * @note    The red byte is the first byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit number [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_GREEN_BIT(led, bit) WS2812_BIT((led), 0, (bit))

/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given blue bit
 *
 * @note    The red byte is the last byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit index [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_BLUE_BIT(led, bit) WS2812_BIT((led), 2, (bit))

#elif (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_RGB)
/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given red bit
 *
 * @note    The red byte is the middle byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit number [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_RED_BIT(led, bit) WS2812_BIT((led), 0, (bit))

/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given green bit
 *
 * @note    The red byte is the first byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit number [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_GREEN_BIT(led, bit) WS2812_BIT((led), 1, (bit))

/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given blue bit
 *
 * @note    The red byte is the last byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit index [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_BLUE_BIT(led, bit) WS2812_BIT((led), 2, (bit))

#elif (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_BGR)
/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given red bit
 *
 * @note    The red byte is the middle byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit number [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_RED_BIT(led, bit) WS2812_BIT((led), 2, (bit))

/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given green bit
 *
 * @note    The red byte is the first byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit number [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_GREEN_BIT(led, bit) WS2812_BIT((led), 1, (bit))

/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given blue bit
 *
 * @note    The red byte is the last byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref RGBLED_NUM)
 * @param[in] bit:                  The bit index [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_BLUE_BIT(led, bit) WS2812_BIT((led), 0, (bit))
#endif

#ifdef RGBW
/**
 * @brief   Determine the index in @ref ws2812_frame_buffer "the frame buffer" of a given white bit
 *
 * @note    The white byte is the last byte in the color packet
 *
 * @param[in] led:                  The led index [0, @ref WS2812_LED_N)
 * @param[in] bit:                  The bit index [0, 7]
 *
 * @return                          The bit index
 */
#    define WS2812_WHITE_BIT(led, bit) WS2812_BIT((led), 3, (bit))
#endif

/* --- PRIVATE VARIABLES ---------------------------------------------------- */

static uint32_t ws2812_frame_buffer[WS2812_BIT_N + 1]; /**< Buffer for a frame */

/* --- PUBLIC FUNCTIONS ----------------------------------------------------- */
/*
 * Gedanke: Double-buffer type transactions: double buffer transfers using two memory pointers for
the memory (while the DMA is reading/writing from/to a buffer, the application can
write/read to/from the other buffer).
 */

void ws2812_init(void) {
    // Initialize led frame buffer
    uint32_t i;
    for (i = 0; i < WS2812_COLOR_BIT_N; i++) ws2812_frame_buffer[i] = WS2812_DUTYCYCLE_0;      // All color bits are zero duty cycle
    for (i = 0; i < WS2812_RESET_BIT_N; i++) ws2812_frame_buffer[i + WS2812_COLOR_BIT_N] = 0;  // All reset bits are zero

    palSetLineMode(RGB_DI_PIN, WS2812_OUTPUT_MODE);

    // PWM Configuration
    //#pragma GCC diagnostic ignored "-Woverride-init"  // Turn off override-init warning for this struct. We use the overriding ability to set a "default" channel config
    static const PWMConfig ws2812_pwm_config = {
        .frequency = WS2812_PWM_FREQUENCY,
        .period    = WS2812_PWM_PERIOD,  // Mit dieser Periode wird UDE-Event erzeugt und ein neuer Wert (Länge WS2812_BIT_N) vom DMA ins CCR geschrieben
        .callback  = NULL,
        .channels =
            {
                [0 ... 3]                = {.mode = PWM_OUTPUT_DISABLED, .callback = NULL},     // Channels default to disabled
                [WS2812_PWM_CHANNEL - 1] = {.mode = WS2812_PWM_OUTPUT_MODE, .callback = NULL},  // Turn on the channel we care about
            },
        .cr2  = 0,
        .dier = TIM_DIER_UDE,  // DMA on update event for next period
    };
    //#pragma GCC diagnostic pop  // Restore command-line warning options

    // Configure DMA
    // dmaInit(); // Joe added this
    dmaStreamAlloc(WS2812_DMA_STREAM - STM32_DMA_STREAM(0), 10, NULL, NULL);
    dmaStreamSetPeripheral(WS2812_DMA_STREAM, &(WS2812_PWM_DRIVER.tim->CCR[WS2812_PWM_CHANNEL - 1]));  // Ziel ist der An-Zeit im Cap-Comp-Register
    dmaStreamSetMemory0(WS2812_DMA_STREAM, ws2812_frame_buffer);
    dmaStreamSetTransactionSize(WS2812_DMA_STREAM, WS2812_BIT_N);
    dmaStreamSetMode(WS2812_DMA_STREAM, STM32_DMA_CR_CHSEL(WS2812_DMA_CHANNEL) | STM32_DMA_CR_DIR_M2P | STM32_DMA_CR_PSIZE_WORD | STM32_DMA_CR_MSIZE_WORD | STM32_DMA_CR_MINC | STM32_DMA_CR_CIRC | STM32_DMA_CR_PL(3));
    // M2P: Memory 2 Periph; PL: Priority Level

#if (STM32_DMA_SUPPORTS_DMAMUX == TRUE)
    // If the MCU has a DMAMUX we need to assign the correct resource
    dmaSetRequestSource(WS2812_DMA_STREAM, WS2812_DMAMUX_ID);
#endif

    // Start DMA
    dmaStreamEnable(WS2812_DMA_STREAM);

    // Configure PWM
    // NOTE: It's required that preload be enabled on the timer channel CCR register. This is currently enabled in the
    // ChibiOS driver code, so we don't have to do anything special to the timer. If we did, we'd have to start the timer,
    // disable counting, enable the channel, and then make whatever configuration changes we need.
    pwmStart(&WS2812_PWM_DRIVER, &ws2812_pwm_config);
    pwmEnableChannel(&WS2812_PWM_DRIVER, WS2812_PWM_CHANNEL - 1, 0);  // Initial period is 0; output will be low until first duty cycle is DMA'd in
}

void ws2812_write_led(uint16_t led_number, uint8_t r, uint8_t g, uint8_t b) {
    // Write color to frame buffer
    for (uint8_t bit = 0; bit < 8; bit++) {
        ws2812_frame_buffer[WS2812_RED_BIT(led_number, bit)]   = ((r >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0;
        ws2812_frame_buffer[WS2812_GREEN_BIT(led_number, bit)] = ((g >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0;
        ws2812_frame_buffer[WS2812_BLUE_BIT(led_number, bit)]  = ((b >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0;
    }
}
void ws2812_write_led_rgbw(uint16_t led_number, uint8_t r, uint8_t g, uint8_t b, uint8_t w) {
    // Write color to frame buffer
    for (uint8_t bit = 0; bit < 8; bit++) {
        ws2812_frame_buffer[WS2812_RED_BIT(led_number, bit)]   = ((r >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0;
        ws2812_frame_buffer[WS2812_GREEN_BIT(led_number, bit)] = ((g >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0;
        ws2812_frame_buffer[WS2812_BLUE_BIT(led_number, bit)]  = ((b >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0;
#ifdef RGBW
        ws2812_frame_buffer[WS2812_WHITE_BIT(led_number, bit)] = ((w >> bit) & 0x01) ? WS2812_DUTYCYCLE_1 : WS2812_DUTYCYCLE_0;
#endif
    }
}

// Setleds for standard RGB
void ws2812_setleds(LED_TYPE* ledarray, uint16_t leds) {
    static bool s_init = false;
    if (!s_init) {
        ws2812_init();
        s_init = true;
    }

    for (uint16_t i = 0; i < leds; i++) {
#ifdef RGBW
        ws2812_write_led_rgbw(i, ledarray[i].r, ledarray[i].g, ledarray[i].b, ledarray[i].w);
#else
        ws2812_write_led(i, ledarray[i].r, ledarray[i].g, ledarray[i].b);
#endif
    }
}