1 files changed, 141 insertions, 0 deletions
diff --git a/drivers/awinic/aw20216.c b/drivers/awinic/aw20216.c
new file mode 100644
index 0000000000..c608c0ab44
--- /dev/null
+++ b/drivers/awinic/aw20216.c
@@ -0,0 +1,141 @@
+/* Copyright 2021 Jasper Chan
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "aw20216.h"
+#include "spi_master.h"
+
+/* The AW20216 appears to be somewhat similar to the IS31FL743, although quite
+ * a few things are different, such as the command byte format and page ordering.
+ * The LED addresses start from 0x00 instead of 0x01.
+ */
+#define AWINIC_ID 0b1010 << 4
+
+#define AW_PAGE_FUNCTION 0x00 << 1    // PG0, Function registers
+#define AW_PAGE_PWM 0x01 << 1         // PG1, LED PWM control
+#define AW_PAGE_SCALING 0x02 << 1     // PG2, LED current scaling control
+#define AW_PAGE_PATCHOICE 0x03 << 1   // PG3, Pattern choice?
+#define AW_PAGE_PWMSCALING 0x04 << 1  // PG4, LED PWM + Scaling control?
+
+#define AW_WRITE 0
+#define AW_READ 1
+
+#define AW_REG_CONFIGURATION 0x00  // PG0
+#define AW_REG_GLOBALCURRENT 0x01  // PG0
+
+// Default value of AW_REG_CONFIGURATION
+// D7:D4 = 1011, SWSEL (SW1~SW12 active)
+// D3 = 0?, reserved (apparently this should be 1 but it doesn't seem to matter)
+// D2:D1 = 00, OSDE (open/short detection enable)
+// D0 = 0, CHIPEN (write 1 to enable LEDs when hardware enable pulled high)
+#define AW_CONFIG_DEFAULT 0b10110000
+#define AW_CHIPEN 1
+
+#define AW_PWM_REGISTER_COUNT 216
+
+#ifndef AW_SCALING_MAX
+#    define AW_SCALING_MAX 150
+#endif
+
+#ifndef AW_GLOBAL_CURRENT_MAX
+#    define AW_GLOBAL_CURRENT_MAX 150
+#endif
+
+#ifndef AW_SPI_DIVISOR
+#    define AW_SPI_DIVISOR 4
+#endif
+
+uint8_t g_pwm_buffer[DRIVER_COUNT][AW_PWM_REGISTER_COUNT];
+bool    g_pwm_buffer_update_required[DRIVER_COUNT] = {false};
+
+bool AW20216_write(pin_t cs_pin, uint8_t page, uint8_t reg, uint8_t* data, uint8_t len) {
+    static uint8_t s_spi_transfer_buffer[2] = {0};
+
+    if (!spi_start(cs_pin, false, 0, AW_SPI_DIVISOR)) {
+        spi_stop();
+        return false;
+    }
+
+    s_spi_transfer_buffer[0] = (AWINIC_ID | page | AW_WRITE);
+    s_spi_transfer_buffer[1] = reg;
+
+    if (spi_transmit(s_spi_transfer_buffer, 2) != SPI_STATUS_SUCCESS) {
+        spi_stop();
+        return false;
+    }
+
+    if (spi_transmit(data, len) != SPI_STATUS_SUCCESS) {
+        spi_stop();
+        return false;
+    }
+
+    spi_stop();
+    return true;
+}
+
+static inline bool AW20216_write_register(pin_t cs_pin, uint8_t page, uint8_t reg, uint8_t value) {
+    // Little wrapper so callers need not care about sending a buffer
+    return AW20216_write(cs_pin, page, reg, &value, 1);
+}
+
+static void AW20216_init_scaling(pin_t cs_pin) {
+    // Set constant current to the max, control brightness with PWM
+    for (uint8_t i = 0; i < AW_PWM_REGISTER_COUNT; i++) {
+        AW20216_write_register(cs_pin, AW_PAGE_SCALING, i, AW_SCALING_MAX);
+    }
+}
+
+static inline void AW20216_init_current_limit(pin_t cs_pin) {
+    // Push config
+    AW20216_write_register(cs_pin, AW_PAGE_FUNCTION, AW_REG_GLOBALCURRENT, AW_GLOBAL_CURRENT_MAX);
+}
+
+static inline void AW20216_soft_enable(pin_t cs_pin) {
+    // Push config
+    AW20216_write_register(cs_pin, AW_PAGE_FUNCTION, AW_REG_CONFIGURATION, AW_CONFIG_DEFAULT | AW_CHIPEN);
+}
+
+void AW20216_init(pin_t cs_pin, pin_t en_pin) {
+    setPinOutput(en_pin);
+    writePinHigh(en_pin);
+
+    // Drivers should start with all scaling and PWM registers as off
+    AW20216_init_current_limit(cs_pin);
+    AW20216_init_scaling(cs_pin);
+
+    AW20216_soft_enable(cs_pin);
+}
+
+void AW20216_set_color(int index, uint8_t red, uint8_t green, uint8_t blue) {
+    aw_led led = g_aw_leds[index];
+
+    g_pwm_buffer[led.driver][led.r]          = red;
+    g_pwm_buffer[led.driver][led.g]          = green;
+    g_pwm_buffer[led.driver][led.b]          = blue;
+    g_pwm_buffer_update_required[led.driver] = true;
+}
+
+void AW20216_set_color_all(uint8_t red, uint8_t green, uint8_t blue) {
+    for (uint8_t i = 0; i < DRIVER_LED_TOTAL; i++) {
+        AW20216_set_color(i, red, green, blue);
+    }
+}
+
+void AW20216_update_pwm_buffers(pin_t cs_pin, uint8_t index) {
+    if (g_pwm_buffer_update_required[index]) {
+        AW20216_write(cs_pin, AW_PAGE_PWM, 0, g_pwm_buffer[index], AW_PWM_REGISTER_COUNT);
+    }
+    g_pwm_buffer_update_required[index] = false;
+}