initial WIP

lots of code copied over, things filled in to hopefully get the LED matrix lighting up. untested.

firmware/app/driver/aw20xxx.c

@@ -0,0 +1,247 @@
+/*
+ * awinic AW20108 / AW20072 / AW20054 / AW20036 LED Matrix Driver
+ *
+ * originally written by true in 2022
+ * while sleep deprived for a super constrained mcu
+ *
+ * some bugs fixed for defcon 32 on aug 6-7, 2024
+ * - don't remember what was fixed
+ *
+ * some bugs fixed for supercon on oct 15, 2024
+ * - fixed support for AW20054, which only supports 9 rows
+ *   did this by respecting aw->rows
+ *
+ *
+ * driver assumptions:
+ * - rows and columns are as is ordered on the chip, lowest to highest
+ *   (if any are skipped, just skip this data in your buffer)
+ * - buffer size does not need to encompass all possible LEDs, only those
+ *   which you have specified you are using.
+ *   ensure sizeof(aw->fade) == aw->rows + aw->cols
+ * - duty cycle will be set automatically according to aw->cols
+ * - all AW20xxx chips will operate on the same i2c bus
+ * - a static data buffer is used
+ *
+ * driver notices:
+ * - updates only happen one column at a time, and are blocking
+ *   (future version may implement a callback when each column is done)
+ * - this driver has not yet implemented the pattern controller
+ * - this driver has not yet implemented the GAIN register, except as
+ *   a global configuration, so dimming only operates 8-bit
+ *   (will be implemented later to allow for beyond-8-bit operation)
+ * - this driver has not yet implemented FADEDIM mode
+ *
+ * if you need anything different, write it yourself
+ */
+
+#include "aw20xxx.h"
+
+
+
+#define AW20X_THIS_PAGE         (aw->state & AW20X_STATE_PAGE_MASK)
+
+#define AW20X_SET_PAGE(x)       if (AW20X_THIS_PAGE != (x)) { \
+                                        aw20x_page(aw, x); \
+                                        aw->state &= ~AW20X_STATE_PAGE_MASK; \
+                                        aw->state |= x; }
+
+
+
+static uint8_t aw_buf[25];      // enough bytes for register and single column FADEDIM update (1 + (12*2))
+
+
+
+void aw20x_page(struct AW20x *aw, uint8_t page)
+{
+    // the datasheet isn't clear on this. the default is zero, and only the lower
+    // three bits are specified. yet the DS says to send 0xCy where y is the page bits.
+    // we'll just do what the DS says even though it contradicts itself.
+    aw_buf[0] = 0xc0 | (page & AW20X_PAGE_MASK);
+    AW20X_I2C_writereg(aw->addr, AW20X_REG_PAGE, aw_buf, 1);
+}
+
+void aw20x_init(struct AW20x *aw, uint8_t addr, uint8_t cols, uint8_t rows, uint8_t imax)
+{
+    // set config register as specified
+    aw->addr   = addr;
+    aw->cols   = cols;
+    aw->rows   = rows;
+    aw->config = imax & AW20X_CONF_IMAX_MASK;
+
+    // wake up (and set page to config page)
+    aw20x_set_sleep(aw, 0);
+
+    // enabled columns
+    aw_buf[0] = cols - 1;
+    while (AW20X_I2C_busy()) {};
+    AW20X_I2C_writereg(aw->addr, AW20X_REG_SIZE, aw_buf, 1);
+
+    // general config
+    aw_buf[0] = imax & AW20X_CONF_IMAX_MASK;
+    while (AW20X_I2C_busy()) {};
+    AW20X_I2C_writereg(aw->addr, AW20X_REG_GCCR, aw_buf, 1);
+}
+
+void aw20x_set_sleep(struct AW20x *aw, uint8_t sleep)
+{
+    // make sure we're on the config page
+    AW20X_SET_PAGE(AW20X_PAGE0_CONFIG);
+
+    aw_buf[0] = sleep ? AW20X_SLPCR_SLEEP : 0;
+
+    // send sleep bit
+    while (AW20X_I2C_busy()) {};
+    AW20X_I2C_writereg(aw->addr, AW20X_REG_SLPCR, aw_buf, 1);
+
+    // set state
+    if (sleep) aw->state |=  AW20X_STATE_SLEEP_MASK;
+    else       aw->state &= ~AW20X_STATE_SLEEP_MASK;
+
+    // burn some cycles if we woke up
+    if (!sleep) AW20X_INIT_DELAY();
+}
+
+void aw20x_set_imax(struct AW20x *aw, uint8_t imax)
+{
+    // make sure we're on the config page
+    AW20X_SET_PAGE(AW20X_PAGE0_CONFIG);
+
+    aw_buf[0] = imax & AW20X_CONF_IMAX_MASK;
+
+    // send imax
+    while (AW20X_I2C_busy()) {};
+    AW20X_I2C_writereg(aw->addr, AW20X_REG_GCCR, aw_buf, 1);
+
+    aw->config = imax & AW20X_CONF_IMAX_MASK;
+}
+
+/*
+ * sends LED values to the chip
+ */
+void aw20x_set_fade(struct AW20x *aw)
+{
+    uint8_t c;
+    uint8_t row;
+    uint8_t offset;
+
+    // make sure we're on the fade page
+    AW20X_SET_PAGE(AW20X_PAGE2_FADE);
+    // don't touch the buffer until we are allowed
+    while (AW20X_I2C_busy()) {};
+
+    row = offset = 0;
+    for (c = 0; c < aw->cols; c++) {
+        // write to chip
+        AW20X_I2C_writereg(aw->addr, offset, aw->fade + row, aw->rows);
+        while (AW20X_I2C_busy());
+        row += aw->rows;
+        offset += AW20X_MAX_ROWS;
+    }
+}
+
+void aw20x_set_dim(struct AW20x *aw)
+{
+    // todo: implement
+}
+
+/*
+ * sets all LEDs to the specified 6-bit DIM value.
+ * used when just using FADE and 8-bit mode
+ * to set initial and fine tune from IMAX the output current.
+ */
+void aw20x_set_dim_global(struct AW20x *aw, uint8_t dim)
+{
+    uint8_t i;
+    uint8_t row;
+    uint8_t offset;
+
+    // ceil
+    if (dim > 0x3f) dim = 0x3f;
+
+    // make sure we're on the dim page
+    AW20X_SET_PAGE(AW20X_PAGE1_DIM);
+    // don't touch the buffer until we are allowed
+    while (AW20X_I2C_busy()) {};
+
+    // clear buffer
+    for (i = 0; i <= aw->rows; i++) aw_buf[i] = dim;
+
+    // send buffer for each column
+    row = offset = 0;
+    for (i = 0; i < aw->cols; i++) {
+        AW20X_I2C_writereg(aw->addr, offset, aw_buf, aw->rows);
+        while (AW20X_I2C_busy());
+        row += aw->rows;
+        offset += AW20X_MAX_ROWS;
+
+    }
+}
+
+void aw20x_commit_fadedim(struct AW20x *aw)
+{
+
+}
+
+void aw20x_led_on(struct AW20x *aw, uint8_t first, uint8_t last, uint8_t on_bit)
+{
+
+}
+/*
+ * enables LEDs based on user LED count, zero-indexed
+ * assumes AW20X_MAX_LEDON_BITS per row but will only turn on active defined rows
+ * AW20036 would be 0-35, but AW20054 would be 0-71 and so on
+ * for example, LEDs 8-12 on AW20054 with 9 roww enabled
+ * would enable C0R8, C1R0, C1R1, C1R2. all other LEDs are disabled
+ *
+ * todo:
+ * - read current state, and apply bitfields to the currently active state
+ * - allow bypassing the readback for faster operation (such as setting all LEDs on at startup)
+ * - make this more efficient (36 LEDs takes ~0.3ms on a 48MHz PIC!)
+*/
+void aw20x_led_enable_range(struct AW20x *aw, uint8_t first, uint8_t last)
+{
+    uint8_t c, r;
+    uint8_t idx;
+    uint8_t boff;
+    uint8_t *buf;
+
+    // make sure we're on the config page
+    AW20X_SET_PAGE(AW20X_PAGE0_CONFIG);
+    // don't touch the buffer until we are allowed
+    while (AW20X_I2C_busy());
+
+    // bits are stored 6 bits per byte, 2 bytes per column, one bit for each row
+    // for a maximum of the AW20X_MAX_ROWS of LED on bits
+    // we only want to touch bits that exist on the chip and in the correct order
+    idx = 0;
+    for (c = 0; c < aw->cols; c++) {
+        buf = &aw_buf[c*2];
+        buf[0] = buf[1] = 0;
+        boff = 0;
+        for (r = 0; r < AW20X_MAX_LEDON_BITS*2; r++) {
+            if (r + idx < first) continue;          // only start at the first led
+            if (r + idx > last) break;              // and stop at the last
+
+            if (r >= aw->rows) continue;            // max bits to process per row
+
+            if (r == AW20X_MAX_LEDON_BITS) {        // only this many bits per byte
+                boff += AW20X_MAX_LEDON_BITS;
+                buf++;
+            }
+
+            *buf |= (1 << (r - boff));
+        }
+        idx += AW20X_MAX_LEDON_BITS*2;
+    }
+
+    AW20X_I2C_writereg(aw->addr, AW20X_REG_LEDON0, aw_buf, c*2);
+}
+
+/*
+ * disables LEDs based on user LED count, zero-indexed
+ * (for example, LEDs 8-12 on AW20054 would enable C0R8, C0R9, C1R0, C1R1)
+*/
+void aw20x_led_disable(struct AW20x *aw, uint8_t first, uint8_t last)
+{
+
+}