RAMA M6-B and IS31FL3218 driver (#4021)

* Initial RAMA M6-B commit.

* Moved IS31FL3218 driver, minor cleanups

* Refactor, added dynamic keymap.

* Added dynamic keymaps to RAMA M6-A

* Refactor M6-A and M6-B to use common code.

* Formatting

* Cleanup

* Cleanup

* Changes from review

drivers/issi/is31fl3218.c

@@ -0,0 +1,102 @@
+/* Copyright 2018 Jason Williams (Wilba)
+ *
+ * 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 "is31fl3218.h"
+#include "i2c_master.h"
+
+// This is the full 8-bit address
+#define ISSI_ADDRESS 0b10101000
+
+// These are the register addresses
+#define ISSI_REG_SHUTDOWN 0x00
+#define ISSI_REG_PWM 0x01
+#define ISSI_REG_CONTROL 0x13
+#define ISSI_REG_UPDATE 0x16
+#define ISSI_REG_RESET 0x17
+
+// Default timeout if no I2C response
+#define ISSI_TIMEOUT 100
+
+// Reusable buffer for transfers
+uint8_t g_twi_transfer_buffer[20];
+
+// IS31FL3218 has 18 PWM outputs and a fixed I2C address, so no chaining.
+// If used as RGB LED driver, LEDs are assigned RGB,RGB,RGB,RGB,RGB,RGB
+uint8_t g_pwm_buffer[18];
+bool g_pwm_buffer_update_required = false;
+
+void IS31FL3218_write_register( uint8_t reg, uint8_t data )
+{
+	g_twi_transfer_buffer[0] = reg;
+	g_twi_transfer_buffer[1] = data;
+	i2c_transmit( ISSI_ADDRESS, g_twi_transfer_buffer, 2, ISSI_TIMEOUT);
+}
+
+void IS31FL3218_write_pwm_buffer( uint8_t *pwm_buffer )
+{
+	g_twi_transfer_buffer[0] = ISSI_REG_PWM;
+	for ( int i=0; i<18; i++ ) {
+		g_twi_transfer_buffer[1+i] = pwm_buffer[i];
+	}
+	
+	i2c_transmit( ISSI_ADDRESS, g_twi_transfer_buffer, 19, ISSI_TIMEOUT);
+}
+
+void IS31FL3218_init(void)
+{
+	// In case we ever want to reinitialize (?)
+	IS31FL3218_write_register( ISSI_REG_RESET, 0x00 );
+	
+	// Turn off software shutdown
+	IS31FL3218_write_register( ISSI_REG_SHUTDOWN, 0x01 );
+
+	// Set all PWM values to zero
+	for ( uint8_t i = 0; i < 18; i++ ) {
+		IS31FL3218_write_register( ISSI_REG_PWM+i, 0x00 );
+	}
+	
+	// Enable all channels
+	for ( uint8_t i = 0; i < 3; i++ ) {
+		IS31FL3218_write_register( ISSI_REG_CONTROL+i, 0b00111111 );
+	}
+	
+	// Load PWM registers and LED Control register data
+	IS31FL3218_write_register( ISSI_REG_UPDATE, 0x01 );
+}
+
+void IS31FL3218_set_color( int index, uint8_t red, uint8_t green, uint8_t blue )
+{
+	g_pwm_buffer[index * 3 + 0] = red;
+	g_pwm_buffer[index * 3 + 1] = green;
+	g_pwm_buffer[index * 3 + 2] = blue;
+	g_pwm_buffer_update_required = true;
+}
+
+void IS31FL3218_set_color_all( uint8_t red, uint8_t green, uint8_t blue )
+{
+	for ( int i = 0; i < 6; i++ ) {
+		IS31FL3218_set_color( i, red, green, blue );
+	}
+}
+
+void IS31FL3218_update_pwm_buffers(void)
+{
+	if ( g_pwm_buffer_update_required ) {
+		IS31FL3218_write_pwm_buffer( g_pwm_buffer );
+		// Load PWM registers and LED Control register data
+		IS31FL3218_write_register( ISSI_REG_UPDATE, 0x01 );
+	}
+	g_pwm_buffer_update_required = false;
+}

drivers/issi/is31fl3218.h

@@ -0,0 +1,24 @@
+/* Copyright 2018 Jason Williams (Wilba)
+ *
+ * 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/>.
+ */
+#pragma once
+
+#include <stdint.h>
+#include <stdbool.h>
+
+void IS31FL3218_init(void);
+void IS31FL3218_set_color( int index, uint8_t red, uint8_t green, uint8_t blue );
+void IS31FL3218_set_color_all( uint8_t red, uint8_t green, uint8_t blue );
+void IS31FL3218_update_pwm_buffers(void);