1 files changed, 60 insertions, 0 deletions
diff --git a/include/driver/pse_ltc4291.h b/include/driver/pse_ltc4291.h
new file mode 100644
index 0000000000..4db9ac4998
--- /dev/null
+++ b/include/driver/pse_ltc4291.h
@@ -0,0 +1,60 @@
+/* Copyright 2023 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/*
+ * The LTC4291 is a power over ethernet (PoE) power sourcing equipment (PSE)
+ * controller.
+ */
+
+#include "i2c.h"
+#include "timer.h"
+#include "util.h"
+
+#define LTC4291_I2C_ADDR 0x2C
+
+#define LTC4291_REG_SUPEVN_COR 0x0B
+#define LTC4291_REG_STATPWR 0x10
+#define LTC4291_REG_STATPIN 0x11
+#define LTC4291_REG_OPMD 0x12
+#define LTC4291_REG_DISENA 0x13
+#define LTC4291_REG_DETENA 0x14
+#define LTC4291_REG_DETPB 0x18
+#define LTC4291_REG_PWRPB 0x19
+#define LTC4291_REG_RSTPB 0x1A
+#define LTC4291_REG_ID 0x1B
+#define LTC4291_REG_DEVID 0x43
+#define LTC4291_REG_HPMD1 0x46
+#define LTC4291_REG_HPMD2 0x4B
+#define LTC4291_REG_HPMD3 0x50
+#define LTC4291_REG_HPMD4 0x55
+#define LTC4291_REG_LPWRPB 0x6E
+
+#define LTC4291_FLD_STATPIN_AUTO BIT(0)
+#define LTC4291_FLD_RSTPB_RSTALL BIT(4)
+
+#define LTC4291_STATPWR_ON_PORT(port) (0x01 << (port))
+#define LTC4291_DETENA_EN_PORT(port) (0x11 << (port))
+#define LTC4291_DETPB_EN_PORT(port) (0x11 << (port))
+#define LTC4291_PWRPB_OFF_PORT(port) (0x10 << (port))
+
+#define LTC4291_OPMD_AUTO 0xFF
+#define LTC4291_DISENA_ALL 0x0F
+#define LTC4291_DETENA_ALL 0xFF
+#define LTC4291_ID 0x64
+#define LTC4291_DEVID 0x38
+#define LTC4291_HPMD_MIN 0x00
+#define LTC4291_HPMD_MAX 0xA8
+
+#define LTC4291_PORT_MAX 4
+
+#define LTC4291_RESET_DELAY_US (20 * MSEC)
+
+#define I2C_PSE_READ(reg, data) \
+	i2c_read8(I2C_PORT_PSE, LTC4291_I2C_ADDR, LTC4291_REG_##reg, (data))
+
+#define I2C_PSE_WRITE(reg, data) \
+	i2c_write8(I2C_PORT_PSE, LTC4291_I2C_ADDR, LTC4291_REG_##reg, (data))
+
+extern const int pse_port_hpmd[LTC4291_PORT_MAX];