+/*
+ * Copyright © 2012 Keith Packard <keithp@keithp.com>
+ *
+ * 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; version 2 of the License.
+ *
+ * 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, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include <ao.h>
+
+static void
+ao_eeprom_wait(void)
+{
+ /* Wait for previous write to complete */
+ while (EECR & (1 << EEPE))
+ ;
+}
+
+static uint8_t
+ao_eeprom_read_byte(uint16_t addr)
+{
+ uint8_t v;
+
+ ao_eeprom_wait();
+ EEAR = addr;
+ cli();
+ EECR |= (1 << EERE);
+ v = EEDR;
+ sei();
+ return v;
+}
+
+static void
+ao_eeprom_write_byte(uint16_t addr, uint8_t v)
+{
+ ao_eeprom_wait();
+ EECR = (0 << EEPM1) | (0 << EEPM0);
+ EEAR = addr;
+ EEDR = v;
+ cli();
+ EECR |= (1 << EEMPE);
+ EECR |= (1 << EEPE);
+ sei();
+}
+
+void
+ao_eeprom_read(uint16_t addr, void *buf, uint16_t len)
+{
+ uint8_t *b = buf;
+
+ while (len--)
+ *b++ = ao_eeprom_read_byte(addr++);
+}
+
+void
+ao_eeprom_write(uint16_t addr, void *buf, uint16_t len)
+{
+ uint8_t *b = buf;
+
+ while (len--)
+ ao_eeprom_write_byte(addr++, *b++);
+}