1 files changed, 79 insertions, 0 deletions
diff --git a/drivers/platform/chrome/cros_ec_lpc_mec.h b/drivers/platform/chrome/cros_ec_lpc_mec.h
new file mode 100644
index 000000000..aa1018f6b
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_lpc_mec.h
@@ -0,0 +1,79 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * LPC variant I/O for Microchip EC
+ *
+ * Copyright (C) 2016 Google, Inc
+ */
+
+#ifndef __CROS_EC_LPC_MEC_H
+#define __CROS_EC_LPC_MEC_H
+
+enum cros_ec_lpc_mec_emi_access_mode {
+	/* 8-bit access */
+	ACCESS_TYPE_BYTE = 0x0,
+	/* 16-bit access */
+	ACCESS_TYPE_WORD = 0x1,
+	/* 32-bit access */
+	ACCESS_TYPE_LONG = 0x2,
+	/*
+	 * 32-bit access, read or write of MEC_EMI_EC_DATA_B3 causes the
+	 * EC data register to be incremented.
+	 */
+	ACCESS_TYPE_LONG_AUTO_INCREMENT = 0x3,
+};
+
+enum cros_ec_lpc_mec_io_type {
+	MEC_IO_READ,
+	MEC_IO_WRITE,
+};
+
+/* EMI registers are relative to base */
+#define MEC_EMI_HOST_TO_EC(MEC_EMI_BASE)	((MEC_EMI_BASE) + 0)
+#define MEC_EMI_EC_TO_HOST(MEC_EMI_BASE)	((MEC_EMI_BASE) + 1)
+#define MEC_EMI_EC_ADDRESS_B0(MEC_EMI_BASE)	((MEC_EMI_BASE) + 2)
+#define MEC_EMI_EC_ADDRESS_B1(MEC_EMI_BASE)	((MEC_EMI_BASE) + 3)
+#define MEC_EMI_EC_DATA_B0(MEC_EMI_BASE)	((MEC_EMI_BASE) + 4)
+#define MEC_EMI_EC_DATA_B1(MEC_EMI_BASE)	((MEC_EMI_BASE) + 5)
+#define MEC_EMI_EC_DATA_B2(MEC_EMI_BASE)	((MEC_EMI_BASE) + 6)
+#define MEC_EMI_EC_DATA_B3(MEC_EMI_BASE)	((MEC_EMI_BASE) + 7)
+
+/**
+ * cros_ec_lpc_mec_init() - Initialize MEC I/O.
+ *
+ * @base: MEC EMI Base address
+ * @end: MEC EMI End address
+ */
+void cros_ec_lpc_mec_init(unsigned int base, unsigned int end);
+
+/*
+ * cros_ec_lpc_mec_destroy
+ *
+ * Cleanup MEC I/O.
+ */
+void cros_ec_lpc_mec_destroy(void);
+
+/**
+ * cros_ec_lpc_mec_in_range() - Determine if addresses are in MEC EMI range.
+ *
+ * @offset: Address offset
+ * @length: Number of bytes to check
+ *
+ * Return: 1 if in range, 0 if not, and -EINVAL on failure
+ *         such as the mec range not being initialized
+ */
+int cros_ec_lpc_mec_in_range(unsigned int offset, unsigned int length);
+
+/**
+ * cros_ec_lpc_io_bytes_mec - Read / write bytes to MEC EMI port
+ *
+ * @io_type: MEC_IO_READ or MEC_IO_WRITE, depending on request
+ * @offset:  Base read / write address
+ * @length:  Number of bytes to read / write
+ * @buf:     Destination / source buffer
+ *
+ * @return 8-bit checksum of all bytes read / written
+ */
+u8 cros_ec_lpc_io_bytes_mec(enum cros_ec_lpc_mec_io_type io_type,
+			    unsigned int offset, unsigned int length, u8 *buf);
+
+#endif /* __CROS_EC_LPC_MEC_H */