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From:   Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
To:     joel@jms.id.au, andrew@aj.id.au, arnd@arndb.de,
        gregkh@linuxfoundation.org, jdelvare@suse.com, linux@roeck-us.net,
        benh@kernel.crashing.org, andrew@lunn.ch
Cc:     linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
        devicetree@vger.kernel.org, linux-hwmon@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, openbmc@lists.ozlabs.org,
        Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Subject: [PATCH v2 4/8] [PATCH 4/8] drivers/peci: Add a PECI adapter driver for Aspeed AST24xx/AST25xx
Date:   Wed, 21 Feb 2018 08:16:02 -0800
Message-Id: <20180221161606.32247-5-jae.hyun.yoo@linux.intel.com>
In-Reply-To: <20180221161606.32247-1-jae.hyun.yoo@linux.intel.com>
References: <20180221161606.32247-1-jae.hyun.yoo@linux.intel.com>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

This commit adds PECI adapter driver implementation for Aspeed
AST24xx/AST25xx.

Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
---
 drivers/peci/Kconfig       |  19 ++
 drivers/peci/Makefile      |   3 +
 drivers/peci/peci-aspeed.c | 510 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 532 insertions(+)
 create mode 100644 drivers/peci/peci-aspeed.c

diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig
index 1cd2cb4b2298..f9875a0d0bc7 100644
--- a/drivers/peci/Kconfig
+++ b/drivers/peci/Kconfig
@@ -14,7 +14,26 @@ config PECI
 	  processor and chipset components to external monitoring or control
 	  devices.
 
+	  If you want PECI support, you should say Y here and also to the
+	  specific driver for your bus adapter(s) below.
+
 	  This PECI support can also be built as a module.  If so, the module
 	  will be called peci-core.
 
+if PECI
+
+config PECI_ASPEED
+	tristate "Aspeed AST24xx/AST25xx PECI support"
+	select REGMAP_MMIO
+	depends on OF && (ARCH_ASPEED || COMPILE_TEST)
+	help
+	  Say Y here if you want support for the Platform Environment Control
+	  Interface (PECI) bus adapter driver on the Aspeed AST24XX and AST25XX
+	  SoCs.
+
+	  This support is also available as a module.  If so, the module
+	  will be called peci-aspeed.
+
+endif # PECI
+
 endmenu
diff --git a/drivers/peci/Makefile b/drivers/peci/Makefile
index 9e8615e0d3ff..886285e69765 100644
--- a/drivers/peci/Makefile
+++ b/drivers/peci/Makefile
@@ -4,3 +4,6 @@
 
 # Core functionality
 obj-$(CONFIG_PECI)		+= peci-core.o
+
+# Hardware specific bus drivers
+obj-$(CONFIG_PECI_ASPEED)	+= peci-aspeed.o
diff --git a/drivers/peci/peci-aspeed.c b/drivers/peci/peci-aspeed.c
new file mode 100644
index 000000000000..2b7800e96805
--- /dev/null
+++ b/drivers/peci/peci-aspeed.c
@@ -0,0 +1,510 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2012-2020 ASPEED Technology Inc.
+// Copyright (c) 2018 Intel Corporation
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/peci.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define DUMP_DEBUG 0
+
+/* Aspeed PECI Registers */
+#define AST_PECI_CTRL     0x00
+#define AST_PECI_TIMING   0x04
+#define AST_PECI_CMD      0x08
+#define AST_PECI_CMD_CTRL 0x0c
+#define AST_PECI_EXP_FCS  0x10
+#define AST_PECI_CAP_FCS  0x14
+#define AST_PECI_INT_CTRL 0x18
+#define AST_PECI_INT_STS  0x1c
+#define AST_PECI_W_DATA0  0x20
+#define AST_PECI_W_DATA1  0x24
+#define AST_PECI_W_DATA2  0x28
+#define AST_PECI_W_DATA3  0x2c
+#define AST_PECI_R_DATA0  0x30
+#define AST_PECI_R_DATA1  0x34
+#define AST_PECI_R_DATA2  0x38
+#define AST_PECI_R_DATA3  0x3c
+#define AST_PECI_W_DATA4  0x40
+#define AST_PECI_W_DATA5  0x44
+#define AST_PECI_W_DATA6  0x48
+#define AST_PECI_W_DATA7  0x4c
+#define AST_PECI_R_DATA4  0x50
+#define AST_PECI_R_DATA5  0x54
+#define AST_PECI_R_DATA6  0x58
+#define AST_PECI_R_DATA7  0x5c
+
+/* AST_PECI_CTRL - 0x00 : Control Register */
+#define PECI_CTRL_SAMPLING_MASK     GENMASK(19, 16)
+#define PECI_CTRL_SAMPLING(x)       (((x) << 16) & PECI_CTRL_SAMPLING_MASK)
+#define PECI_CTRL_SAMPLING_GET(x)   (((x) & PECI_CTRL_SAMPLING_MASK) >> 16)
+#define PECI_CTRL_READ_MODE_MASK    GENMASK(13, 12)
+#define PECI_CTRL_READ_MODE(x)      (((x) << 12) & PECI_CTRL_READ_MODE_MASK)
+#define PECI_CTRL_READ_MODE_GET(x)  (((x) & PECI_CTRL_READ_MODE_MASK) >> 12)
+#define PECI_CTRL_READ_MODE_COUNT   BIT(12)
+#define PECI_CTRL_READ_MODE_DBG     BIT(13)
+#define PECI_CTRL_CLK_SOURCE_MASK   BIT(11)
+#define PECI_CTRL_CLK_SOURCE(x)     (((x) << 11) & PECI_CTRL_CLK_SOURCE_MASK)
+#define PECI_CTRL_CLK_SOURCE_GET(x) (((x) & PECI_CTRL_CLK_SOURCE_MASK) >> 11)
+#define PECI_CTRL_CLK_DIV_MASK      GENMASK(10, 8)
+#define PECI_CTRL_CLK_DIV(x)        (((x) << 8) & PECI_CTRL_CLK_DIV_MASK)
+#define PECI_CTRL_CLK_DIV_GET(x)    (((x) & PECI_CTRL_CLK_DIV_MASK) >> 8)
+#define PECI_CTRL_INVERT_OUT        BIT(7)
+#define PECI_CTRL_INVERT_IN         BIT(6)
+#define PECI_CTRL_BUS_CONTENT_EN    BIT(5)
+#define PECI_CTRL_PECI_EN           BIT(4)
+#define PECI_CTRL_PECI_CLK_EN       BIT(0)
+
+/* AST_PECI_TIMING - 0x04 : Timing Negotiation Register */
+#define PECI_TIMING_MESSAGE_MASK   GENMASK(15, 8)
+#define PECI_TIMING_MESSAGE(x)     (((x) << 8) & PECI_TIMING_MESSAGE_MASK)
+#define PECI_TIMING_MESSAGE_GET(x) (((x) & PECI_TIMING_MESSAGE_MASK) >> 8)
+#define PECI_TIMING_ADDRESS_MASK   GENMASK(7, 0)
+#define PECI_TIMING_ADDRESS(x)     ((x) & PECI_TIMING_ADDRESS_MASK)
+#define PECI_TIMING_ADDRESS_GET(x) ((x) & PECI_TIMING_ADDRESS_MASK)
+
+/* AST_PECI_CMD - 0x08 : Command Register */
+#define PECI_CMD_PIN_MON    BIT(31)
+#define PECI_CMD_STS_MASK   GENMASK(27, 24)
+#define PECI_CMD_STS_GET(x) (((x) & PECI_CMD_STS_MASK) >> 24)
+#define PECI_CMD_FIRE       BIT(0)
+
+/* AST_PECI_LEN - 0x0C : Read/Write Length Register */
+#define PECI_AW_FCS_EN       BIT(31)
+#define PECI_READ_LEN_MASK   GENMASK(23, 16)
+#define PECI_READ_LEN(x)     (((x) << 16) & PECI_READ_LEN_MASK)
+#define PECI_WRITE_LEN_MASK  GENMASK(15, 8)
+#define PECI_WRITE_LEN(x)    (((x) << 8) & PECI_WRITE_LEN_MASK)
+#define PECI_TAGET_ADDR_MASK GENMASK(7, 0)
+#define PECI_TAGET_ADDR(x)   ((x) & PECI_TAGET_ADDR_MASK)
+
+/* AST_PECI_EXP_FCS - 0x10 : Expected FCS Data Register */
+#define PECI_EXPECT_READ_FCS_MASK      GENMASK(23, 16)
+#define PECI_EXPECT_READ_FCS_GET(x)    (((x) & PECI_EXPECT_READ_FCS_MASK) >> 16)
+#define PECI_EXPECT_AW_FCS_AUTO_MASK   GENMASK(15, 8)
+#define PECI_EXPECT_AW_FCS_AUTO_GET(x) (((x) & PECI_EXPECT_AW_FCS_AUTO_MASK) \
+					>> 8)
+#define PECI_EXPECT_WRITE_FCS_MASK     GENMASK(7, 0)
+#define PECI_EXPECT_WRITE_FCS_GET(x)   ((x) & PECI_EXPECT_WRITE_FCS_MASK)
+
+/* AST_PECI_CAP_FCS - 0x14 : Captured FCS Data Register */
+#define PECI_CAPTURE_READ_FCS_MASK    GENMASK(23, 16)
+#define PECI_CAPTURE_READ_FCS_GET(x)  (((x) & PECI_CAPTURE_READ_FCS_MASK) >> 16)
+#define PECI_CAPTURE_WRITE_FCS_MASK   GENMASK(7, 0)
+#define PECI_CAPTURE_WRITE_FCS_GET(x) ((x) & PECI_CAPTURE_WRITE_FCS_MASK)
+
+/* AST_PECI_INT_CTRL/STS - 0x18/0x1c : Interrupt Register */
+#define PECI_INT_TIMING_RESULT_MASK GENMASK(31, 30)
+#define PECI_INT_TIMEOUT            BIT(4)
+#define PECI_INT_CONNECT            BIT(3)
+#define PECI_INT_W_FCS_BAD          BIT(2)
+#define PECI_INT_W_FCS_ABORT        BIT(1)
+#define PECI_INT_CMD_DONE           BIT(0)
+
+struct aspeed_peci {
+	struct peci_adapter	adaper;
+	struct device		*dev;
+	struct regmap		*regmap;
+	int			irq;
+	struct completion	xfer_complete;
+	u32			sts;
+	u32			cmd_timeout_ms;
+};
+
+#define PECI_INT_MASK  (PECI_INT_TIMEOUT | PECI_INT_CONNECT | \
+			PECI_INT_W_FCS_BAD | PECI_INT_W_FCS_ABORT | \
+			PECI_INT_CMD_DONE)
+
+#define PECI_IDLE_CHECK_TIMEOUT_MS      50
+#define PECI_IDLE_CHECK_INTERVAL_MS     10
+
+#define PECI_RD_SAMPLING_POINT_DEFAULT  8
+#define PECI_RD_SAMPLING_POINT_MAX      15
+#define PECI_CLK_DIV_DEFAULT            0
+#define PECI_CLK_DIV_MAX                7
+#define PECI_MSG_TIMING_NEGO_DEFAULT    1
+#define PECI_MSG_TIMING_NEGO_MAX        255
+#define PECI_ADDR_TIMING_NEGO_DEFAULT   1
+#define PECI_ADDR_TIMING_NEGO_MAX       255
+#define PECI_CMD_TIMEOUT_MS_DEFAULT     1000
+#define PECI_CMD_TIMEOUT_MS_MAX         60000
+
+static int aspeed_peci_xfer_native(struct aspeed_peci *priv,
+				   struct peci_xfer_msg *msg)
+{
+	u32 peci_head, peci_state, rx_data, cmd_sts;
+	uint reg;
+	ktime_t start, end;
+	s64 elapsed_ms;
+	long err, timeout = msecs_to_jiffies(priv->cmd_timeout_ms);
+	int i, rc = 0;
+
+	start = ktime_get();
+
+	/* Check command sts and bus idle state */
+	while (!regmap_read(priv->regmap, AST_PECI_CMD, &cmd_sts) &&
+	       (cmd_sts & (PECI_CMD_STS_MASK | PECI_CMD_PIN_MON))) {
+		end = ktime_get();
+		elapsed_ms = ktime_to_ms(ktime_sub(end, start));
+		if (elapsed_ms >= PECI_IDLE_CHECK_TIMEOUT_MS) {
+			dev_dbg(priv->dev, "Timeout waiting for idle state!\n");
+			return -ETIMEDOUT;
+		}
+
+		usleep_range(PECI_IDLE_CHECK_INTERVAL_MS * 1000,
+			     (PECI_IDLE_CHECK_INTERVAL_MS * 1000) + 1000);
+	};
+
+	reinit_completion(&priv->xfer_complete);
+
+	peci_head = PECI_TAGET_ADDR(msg->addr) |
+				    PECI_WRITE_LEN(msg->tx_len) |
+				    PECI_READ_LEN(msg->rx_len);
+
+	rc = regmap_write(priv->regmap, AST_PECI_CMD_CTRL, peci_head);
+	if (rc)
+		return rc;
+
+	for (i = 0; i < msg->tx_len; i += 4) {
+		reg = i < 16 ? AST_PECI_W_DATA0 + i % 16 :
+			       AST_PECI_W_DATA4 + i % 16;
+		rc = regmap_write(priv->regmap, reg,
+				  (msg->tx_buf[i + 3] << 24) |
+				  (msg->tx_buf[i + 2] << 16) |
+				  (msg->tx_buf[i + 1] << 8) |
+				  msg->tx_buf[i + 0]);
+		if (rc)
+			return rc;
+	}
+
+	dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head);
+#if DUMP_DEBUG
+	print_hex_dump(KERN_DEBUG, "TX : ", DUMP_PREFIX_NONE, 16, 1,
+		       msg->tx_buf, msg->tx_len, true);
+#endif
+
+	rc = regmap_write(priv->regmap, AST_PECI_CMD, PECI_CMD_FIRE);
+	if (rc)
+		return rc;
+
+	err = wait_for_completion_interruptible_timeout(&priv->xfer_complete,
+							timeout);
+
+	dev_dbg(priv->dev, "INT_STS : 0x%08x\n", priv->sts);
+	if (!regmap_read(priv->regmap, AST_PECI_CMD, &peci_state))
+		dev_dbg(priv->dev, "PECI_STATE : 0x%lx\n",
+			PECI_CMD_STS_GET(peci_state));
+	else
+		dev_dbg(priv->dev, "PECI_STATE : read error\n");
+
+	if (err <= 0 || !(priv->sts & PECI_INT_CMD_DONE)) {
+		if (err < 0) { /* -ERESTARTSYS */
+			return (int)err;
+		} else if (err == 0) {
+			dev_dbg(priv->dev, "Timeout waiting for a response!\n");
+			return -ETIMEDOUT;
+		}
+
+		dev_dbg(priv->dev, "No valid response!\n");
+		return -EFAULT;
+	}
+
+	for (i = 0; i < msg->rx_len; i++) {
+		u8 byte_offset = i % 4;
+
+		if (byte_offset == 0) {
+			reg = i < 16 ? AST_PECI_R_DATA0 + i % 16 :
+				       AST_PECI_R_DATA4 + i % 16;
+			rc = regmap_read(priv->regmap, reg, &rx_data);
+			if (rc)
+				return rc;
+		}
+
+		msg->rx_buf[i] = (u8)(rx_data >> (byte_offset << 3));
+	}
+
+#if DUMP_DEBUG
+	print_hex_dump(KERN_DEBUG, "RX : ", DUMP_PREFIX_NONE, 16, 1,
+		       msg->rx_buf, msg->rx_len, true);
+#endif
+	if (!regmap_read(priv->regmap, AST_PECI_CMD, &peci_state))
+		dev_dbg(priv->dev, "PECI_STATE : 0x%lx\n",
+			PECI_CMD_STS_GET(peci_state));
+	else
+		dev_dbg(priv->dev, "PECI_STATE : read error\n");
+	dev_dbg(priv->dev, "------------------------\n");
+
+	return rc;
+}
+
+static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg)
+{
+	struct aspeed_peci *priv = arg;
+	bool valid_irq = true;
+
+	if (regmap_read(priv->regmap, AST_PECI_INT_STS, &priv->sts))
+		return IRQ_NONE;
+
+	switch (priv->sts & PECI_INT_MASK) {
+	case PECI_INT_TIMEOUT:
+		dev_dbg(priv->dev, "PECI_INT_TIMEOUT\n");
+		if (regmap_write(priv->regmap, AST_PECI_INT_STS,
+				 PECI_INT_TIMEOUT))
+			return IRQ_NONE;
+		break;
+	case PECI_INT_CONNECT:
+		dev_dbg(priv->dev, "PECI_INT_CONNECT\n");
+		if (regmap_write(priv->regmap, AST_PECI_INT_STS,
+				 PECI_INT_CONNECT))
+			return IRQ_NONE;
+		break;
+	case PECI_INT_W_FCS_BAD:
+		dev_dbg(priv->dev, "PECI_INT_W_FCS_BAD\n");
+		if (regmap_write(priv->regmap, AST_PECI_INT_STS,
+				 PECI_INT_W_FCS_BAD))
+			return IRQ_NONE;
+		break;
+	case PECI_INT_W_FCS_ABORT:
+		dev_dbg(priv->dev, "PECI_INT_W_FCS_ABORT\n");
+		if (regmap_write(priv->regmap, AST_PECI_INT_STS,
+				 PECI_INT_W_FCS_ABORT))
+			return IRQ_NONE;
+		break;
+	case PECI_INT_CMD_DONE:
+		dev_dbg(priv->dev, "PECI_INT_CMD_DONE\n");
+		if (regmap_write(priv->regmap, AST_PECI_INT_STS,
+				 PECI_INT_CMD_DONE) ||
+		    regmap_write(priv->regmap, AST_PECI_CMD, 0))
+			return IRQ_NONE;
+		break;
+	default:
+		dev_dbg(priv->dev, "Unknown PECI interrupt : 0x%08x\n",
+			priv->sts);
+		if (regmap_write(priv->regmap, AST_PECI_INT_STS, priv->sts))
+			return IRQ_NONE;
+		valid_irq = false;
+		break;
+	}
+
+	if (valid_irq)
+		complete(&priv->xfer_complete);
+
+	return IRQ_HANDLED;
+}
+
+static int aspeed_peci_init_ctrl(struct aspeed_peci *priv)
+{
+	struct clk *clkin;
+	u32 clk_freq, clk_divisor, clk_div_val = 0;
+	u32 msg_timing_nego, addr_timing_nego, rd_sampling_point;
+	int ret;
+
+	clkin = devm_clk_get(priv->dev, NULL);
+	if (IS_ERR(clkin)) {
+		dev_err(priv->dev, "Failed to get clk source.\n");
+		return PTR_ERR(clkin);
+	}
+
+	ret = of_property_read_u32(priv->dev->of_node, "clock-frequency",
+				   &clk_freq);
+	if (ret < 0) {
+		dev_err(priv->dev,
+			"Could not read clock-frequency property.\n");
+		return ret;
+	}
+
+	clk_divisor = clk_get_rate(clkin) / clk_freq;
+	devm_clk_put(priv->dev, clkin);
+
+	while ((clk_divisor >> 1) && (clk_div_val < PECI_CLK_DIV_MAX))
+		clk_div_val++;
+
+	ret = of_property_read_u32(priv->dev->of_node, "msg-timing-nego",
+				   &msg_timing_nego);
+	if (ret || msg_timing_nego > PECI_MSG_TIMING_NEGO_MAX) {
+		dev_warn(priv->dev,
+			 "Invalid msg-timing-nego : %u, Use default : %u\n",
+			 msg_timing_nego, PECI_MSG_TIMING_NEGO_DEFAULT);
+		msg_timing_nego = PECI_MSG_TIMING_NEGO_DEFAULT;
+	}
+
+	ret = of_property_read_u32(priv->dev->of_node, "addr-timing-nego",
+				   &addr_timing_nego);
+	if (ret || addr_timing_nego > PECI_ADDR_TIMING_NEGO_MAX) {
+		dev_warn(priv->dev,
+			 "Invalid addr-timing-nego : %u, Use default : %u\n",
+			 addr_timing_nego, PECI_ADDR_TIMING_NEGO_DEFAULT);
+		addr_timing_nego = PECI_ADDR_TIMING_NEGO_DEFAULT;
+	}
+
+	ret = of_property_read_u32(priv->dev->of_node, "rd-sampling-point",
+				   &rd_sampling_point);
+	if (ret || rd_sampling_point > PECI_RD_SAMPLING_POINT_MAX) {
+		dev_warn(priv->dev,
+			 "Invalid rd-sampling-point : %u. Use default : %u\n",
+			 rd_sampling_point,
+			 PECI_RD_SAMPLING_POINT_DEFAULT);
+		rd_sampling_point = PECI_RD_SAMPLING_POINT_DEFAULT;
+	}
+
+	ret = of_property_read_u32(priv->dev->of_node, "cmd-timeout-ms",
+				   &priv->cmd_timeout_ms);
+	if (ret || priv->cmd_timeout_ms > PECI_CMD_TIMEOUT_MS_MAX ||
+	    priv->cmd_timeout_ms == 0) {
+		dev_warn(priv->dev,
+			 "Invalid cmd-timeout-ms : %u. Use default : %u\n",
+			 priv->cmd_timeout_ms,
+			 PECI_CMD_TIMEOUT_MS_DEFAULT);
+		priv->cmd_timeout_ms = PECI_CMD_TIMEOUT_MS_DEFAULT;
+	}
+
+	ret = regmap_write(priv->regmap, AST_PECI_CTRL,
+			   PECI_CTRL_CLK_DIV(PECI_CLK_DIV_DEFAULT) |
+			   PECI_CTRL_PECI_CLK_EN);
+	if (ret)
+		return ret;
+
+	usleep_range(1000, 5000);
+
+	/**
+	 * Timing negotiation period setting.
+	 * The unit of the programmed value is 4 times of PECI clock period.
+	 */
+	ret = regmap_write(priv->regmap, AST_PECI_TIMING,
+			   PECI_TIMING_MESSAGE(msg_timing_nego) |
+			   PECI_TIMING_ADDRESS(addr_timing_nego));
+	if (ret)
+		return ret;
+
+	/* Clear interrupts */
+	ret = regmap_write(priv->regmap, AST_PECI_INT_STS, PECI_INT_MASK);
+	if (ret)
+		return ret;
+
+	/* Enable interrupts */
+	ret = regmap_write(priv->regmap, AST_PECI_INT_CTRL, PECI_INT_MASK);
+	if (ret)
+		return ret;
+
+	/* Read sampling point and clock speed setting */
+	ret = regmap_write(priv->regmap, AST_PECI_CTRL,
+			   PECI_CTRL_SAMPLING(rd_sampling_point) |
+			   PECI_CTRL_CLK_DIV(clk_div_val) |
+			   PECI_CTRL_PECI_EN | PECI_CTRL_PECI_CLK_EN);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static const struct regmap_config aspeed_peci_regmap_config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = AST_PECI_R_DATA7,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+	.fast_io = true,
+};
+
+static int aspeed_peci_xfer(struct peci_adapter *adaper,
+			    struct peci_xfer_msg *msg)
+{
+	struct aspeed_peci *priv = peci_get_adapdata(adaper);
+
+	return aspeed_peci_xfer_native(priv, msg);
+}
+
+static int aspeed_peci_probe(struct platform_device *pdev)
+{
+	struct aspeed_peci *priv;
+	struct resource *res;
+	void __iomem *base;
+	int ret = 0;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	dev_set_drvdata(&pdev->dev, priv);
+	priv->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+					     &aspeed_peci_regmap_config);
+	if (IS_ERR(priv->regmap))
+		return PTR_ERR(priv->regmap);
+
+	priv->irq = platform_get_irq(pdev, 0);
+	if (!priv->irq)
+		return -ENODEV;
+
+	ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler,
+			       IRQF_SHARED,
+			       "peci-aspeed-irq",
+			       priv);
+	if (ret < 0)
+		return ret;
+
+	init_completion(&priv->xfer_complete);
+
+	priv->adaper.dev.parent = priv->dev;
+	priv->adaper.dev.of_node = of_node_get(dev_of_node(priv->dev));
+	strlcpy(priv->adaper.name, pdev->name, sizeof(priv->adaper.name));
+	priv->adaper.xfer = aspeed_peci_xfer;
+	peci_set_adapdata(&priv->adaper, priv);
+
+	ret = aspeed_peci_init_ctrl(priv);
+	if (ret < 0)
+		return ret;
+
+	ret = peci_add_adapter(&priv->adaper);
+	if (ret < 0)
+		return ret;
+
+	dev_info(&pdev->dev, "peci bus %d registered, irq %d\n",
+		 priv->adaper.nr, priv->irq);
+
+	return 0;
+}
+
+static int aspeed_peci_remove(struct platform_device *pdev)
+{
+	struct aspeed_peci *priv = dev_get_drvdata(&pdev->dev);
+
+	peci_del_adapter(&priv->adaper);
+	of_node_put(priv->adaper.dev.of_node);
+
+	return 0;
+}
+
+static const struct of_device_id aspeed_peci_of_table[] = {
+	{ .compatible = "aspeed,ast2400-peci", },
+	{ .compatible = "aspeed,ast2500-peci", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, aspeed_peci_of_table);
+
+static struct platform_driver aspeed_peci_driver = {
+	.probe  = aspeed_peci_probe,
+	.remove = aspeed_peci_remove,
+	.driver = {
+		.name           = "peci-aspeed",
+		.of_match_table = of_match_ptr(aspeed_peci_of_table),
+	},
+};
+module_platform_driver(aspeed_peci_driver);
+
+MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
+MODULE_AUTHOR("Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>");
+MODULE_DESCRIPTION("Aspeed PECI driver");
+MODULE_LICENSE("GPL v2");
-- 
2.16.1