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Cc:     linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org,
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        Robin Murphy <robin.murphy@arm.com>,
        Ryan Chen <ryan_chen@aspeedtech.com>,
        Haiyue Wang <haiyue.wang@linux.intel.com>,
        James Feist <james.feist@linux.intel.com>,
        Vernon Mauery <vernon.mauery@linux.intel.com>
Subject: [PATCH v10 06/12] peci: Add a PECI adapter driver for Aspeed AST24xx/AST25xx
Date:   Mon,  7 Jan 2019 13:41:30 -0800
Message-Id: <20190107214136.5256-7-jae.hyun.yoo@linux.intel.com>
In-Reply-To: <20190107214136.5256-1-jae.hyun.yoo@linux.intel.com>
References: <20190107214136.5256-1-jae.hyun.yoo@linux.intel.com>
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Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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

Cc: Joel Stanley <joel@jms.id.au>
Cc: Andrew Jeffery <andrew@aj.id.au>
Cc: Andy Shevchenko <andriy.shevchenko@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Ryan Chen <ryan_chen@aspeedtech.com>
Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Reviewed-by: Haiyue Wang <haiyue.wang@linux.intel.com>
Reviewed-by: James Feist <james.feist@linux.intel.com>
Reviewed-by: Vernon Mauery <vernon.mauery@linux.intel.com>
---
 drivers/peci/Kconfig       |  27 ++
 drivers/peci/Makefile      |   3 +
 drivers/peci/peci-aspeed.c | 505 +++++++++++++++++++++++++++++++++++++
 3 files changed, 535 insertions(+)
 create mode 100644 drivers/peci/peci-aspeed.c

diff --git a/drivers/peci/Kconfig b/drivers/peci/Kconfig
index 4ccacb22a356..9e9845ebcff4 100644
--- a/drivers/peci/Kconfig
+++ b/drivers/peci/Kconfig
@@ -10,3 +10,30 @@ config PECI
 	  The Platform Environment Control Interface (PECI) is a one-wire bus
 	  interface that provides a communication channel from Intel processors
 	  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.
+
+if PECI
+
+#
+# PECI hardware bus configuration
+#
+
+menu "PECI Hardware Bus support"
+
+config PECI_ASPEED
+	tristate "ASPEED PECI support"
+	select REGMAP_MMIO
+	depends on OF
+	depends on 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 SoCs.
+
+	  This support is also available as a module.  If so, the module
+	  will be called peci-aspeed.
+
+endmenu
+
+endif # PECI
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..2293d4e56e63
--- /dev/null
+++ b/drivers/peci/peci-aspeed.c
@@ -0,0 +1,505 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2012-2017 ASPEED Technology Inc.
+// Copyright (c) 2018-2019 Intel Corporation
+
+#include <linux/bitfield.h>
+#include <linux/clk.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>
+#include <linux/reset.h>
+
+/* ASPEED PECI Registers */
+#define ASPEED_PECI_CTRL     0x00
+#define ASPEED_PECI_TIMING   0x04
+#define ASPEED_PECI_CMD      0x08
+#define ASPEED_PECI_CMD_CTRL 0x0c
+#define ASPEED_PECI_EXP_FCS  0x10
+#define ASPEED_PECI_CAP_FCS  0x14
+#define ASPEED_PECI_INT_CTRL 0x18
+#define ASPEED_PECI_INT_STS  0x1c
+#define ASPEED_PECI_W_DATA0  0x20
+#define ASPEED_PECI_W_DATA1  0x24
+#define ASPEED_PECI_W_DATA2  0x28
+#define ASPEED_PECI_W_DATA3  0x2c
+#define ASPEED_PECI_R_DATA0  0x30
+#define ASPEED_PECI_R_DATA1  0x34
+#define ASPEED_PECI_R_DATA2  0x38
+#define ASPEED_PECI_R_DATA3  0x3c
+#define ASPEED_PECI_W_DATA4  0x40
+#define ASPEED_PECI_W_DATA5  0x44
+#define ASPEED_PECI_W_DATA6  0x48
+#define ASPEED_PECI_W_DATA7  0x4c
+#define ASPEED_PECI_R_DATA4  0x50
+#define ASPEED_PECI_R_DATA5  0x54
+#define ASPEED_PECI_R_DATA6  0x58
+#define ASPEED_PECI_R_DATA7  0x5c
+
+/* ASPEED_PECI_CTRL - 0x00 : Control Register */
+#define PECI_CTRL_SAMPLING_MASK      GENMASK(19, 16)
+#define PECI_CTRL_READ_MODE_MASK     GENMASK(13, 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_DIV_MASK       GENMASK(10, 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)
+
+/* ASPEED_PECI_TIMING - 0x04 : Timing Negotiation Register */
+#define PECI_TIMING_MESSAGE_MASK     GENMASK(15, 8)
+#define PECI_TIMING_ADDRESS_MASK     GENMASK(7, 0)
+
+/* ASPEED_PECI_CMD - 0x08 : Command Register */
+#define PECI_CMD_PIN_MON             BIT(31)
+#define PECI_CMD_STS_MASK            GENMASK(27, 24)
+#define PECI_CMD_IDLE_MASK           (PECI_CMD_STS_MASK | PECI_CMD_PIN_MON)
+#define PECI_CMD_FIRE                BIT(0)
+
+/* ASPEED_PECI_LEN - 0x0C : Read/Write Length Register */
+#define PECI_AW_FCS_EN               BIT(31)
+#define PECI_READ_LEN_MASK           GENMASK(23, 16)
+#define PECI_WRITE_LEN_MASK          GENMASK(15, 8)
+#define PECI_TAGET_ADDR_MASK         GENMASK(7, 0)
+
+/* ASPEED_PECI_EXP_FCS - 0x10 : Expected FCS Data Register */
+#define PECI_EXPECT_READ_FCS_MASK    GENMASK(23, 16)
+#define PECI_EXPECT_AW_FCS_AUTO_MASK GENMASK(15, 8)
+#define PECI_EXPECT_WRITE_FCS_MASK   GENMASK(7, 0)
+
+/* ASPEED_PECI_CAP_FCS - 0x14 : Captured FCS Data Register */
+#define PECI_CAPTURE_READ_FCS_MASK   GENMASK(23, 16)
+#define PECI_CAPTURE_WRITE_FCS_MASK  GENMASK(7, 0)
+
+/* ASPEED_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)
+
+#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_USEC    50000
+#define PECI_IDLE_CHECK_INTERVAL_USEC   10000
+
+#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_DEFAULT         1
+#define PECI_MSG_TIMING_MAX             255
+#define PECI_ADDR_TIMING_DEFAULT        1
+#define PECI_ADDR_TIMING_MAX            255
+#define PECI_CMD_TIMEOUT_MS_DEFAULT     1000
+#define PECI_CMD_TIMEOUT_MS_MAX         60000
+
+struct aspeed_peci {
+	struct peci_adapter	*adapter;
+	struct device		*dev;
+	struct regmap		*regmap;
+	struct clk		*clk;
+	struct reset_control	*rst;
+	int			irq;
+	spinlock_t		lock; /* to sync completion status handling */
+	struct completion	xfer_complete;
+	u32			status;
+	u32			cmd_timeout_ms;
+};
+
+static int aspeed_peci_xfer_native(struct aspeed_peci *priv,
+				   struct peci_xfer_msg *msg)
+{
+	long err, timeout = msecs_to_jiffies(priv->cmd_timeout_ms);
+	u32 peci_head, peci_state, rx_data, cmd_sts;
+	unsigned long flags;
+	int i, rc;
+	uint reg;
+
+	/* Check command sts and bus idle state */
+	rc = regmap_read_poll_timeout(priv->regmap, ASPEED_PECI_CMD, cmd_sts,
+				      !(cmd_sts & PECI_CMD_IDLE_MASK),
+				      PECI_IDLE_CHECK_INTERVAL_USEC,
+				      PECI_IDLE_CHECK_TIMEOUT_USEC);
+	if (rc)
+		return rc; /* -ETIMEDOUT */
+
+	spin_lock_irqsave(&priv->lock, flags);
+	reinit_completion(&priv->xfer_complete);
+
+	peci_head = FIELD_PREP(PECI_TAGET_ADDR_MASK, msg->addr) |
+		    FIELD_PREP(PECI_WRITE_LEN_MASK, msg->tx_len) |
+		    FIELD_PREP(PECI_READ_LEN_MASK, msg->rx_len);
+
+	regmap_write(priv->regmap, ASPEED_PECI_CMD_CTRL, peci_head);
+
+	for (i = 0; i < msg->tx_len; i += 4) {
+		reg = i < 16 ? ASPEED_PECI_W_DATA0 + i % 16 :
+			       ASPEED_PECI_W_DATA4 + i % 16;
+		regmap_write(priv->regmap, reg,
+			     le32_to_cpup((__le32 *)&msg->tx_buf[i]));
+	}
+
+	dev_dbg(priv->dev, "HEAD : 0x%08x\n", peci_head);
+	print_hex_dump_debug("TX : ", DUMP_PREFIX_NONE, 16, 1,
+			     msg->tx_buf, msg->tx_len, true);
+
+	priv->status = 0;
+	regmap_write(priv->regmap, ASPEED_PECI_CMD, PECI_CMD_FIRE);
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	err = wait_for_completion_interruptible_timeout(&priv->xfer_complete,
+							timeout);
+
+	spin_lock_irqsave(&priv->lock, flags);
+	dev_dbg(priv->dev, "INT_STS : 0x%08x\n", priv->status);
+	regmap_read(priv->regmap, ASPEED_PECI_CMD, &peci_state);
+	dev_dbg(priv->dev, "PECI_STATE : 0x%lx\n",
+		FIELD_GET(PECI_CMD_STS_MASK, peci_state));
+
+	regmap_write(priv->regmap, ASPEED_PECI_CMD, 0);
+
+	if (err <= 0 || priv->status != PECI_INT_CMD_DONE) {
+		if (err < 0) { /* -ERESTARTSYS */
+			rc = (int)err;
+			goto err_irqrestore;
+		} else if (err == 0) {
+			dev_dbg(priv->dev, "Timeout waiting for a response!\n");
+			rc = -ETIMEDOUT;
+			goto err_irqrestore;
+		}
+
+		dev_dbg(priv->dev, "No valid response!\n");
+		rc = -EIO;
+		goto err_irqrestore;
+	}
+
+	/**
+	 * Note that rx_len and rx_buf size can be an odd number.
+	 * Byte handling is more efficient.
+	 */
+	for (i = 0; i < msg->rx_len; i++) {
+		u8 byte_offset = i % 4;
+
+		if (byte_offset == 0) {
+			reg = i < 16 ? ASPEED_PECI_R_DATA0 + i % 16 :
+				       ASPEED_PECI_R_DATA4 + i % 16;
+			regmap_read(priv->regmap, reg, &rx_data);
+		}
+
+		msg->rx_buf[i] = (u8)(rx_data >> (byte_offset << 3));
+	}
+
+	print_hex_dump_debug("RX : ", DUMP_PREFIX_NONE, 16, 1,
+			     msg->rx_buf, msg->rx_len, true);
+
+	regmap_read(priv->regmap, ASPEED_PECI_CMD, &peci_state);
+	dev_dbg(priv->dev, "PECI_STATE : 0x%lx\n",
+		FIELD_GET(PECI_CMD_STS_MASK, peci_state));
+	dev_dbg(priv->dev, "------------------------\n");
+
+err_irqrestore:
+	spin_unlock_irqrestore(&priv->lock, flags);
+	return rc;
+}
+
+static irqreturn_t aspeed_peci_irq_handler(int irq, void *arg)
+{
+	struct aspeed_peci *priv = arg;
+	u32 status_ack = 0;
+	u32 status;
+
+	spin_lock(&priv->lock);
+	regmap_read(priv->regmap, ASPEED_PECI_INT_STS, &status);
+	priv->status |= (status & PECI_INT_MASK);
+
+	/**
+	 * In most cases, interrupt bits will be set one by one but also note
+	 * that multiple interrupt bits could be set at the same time.
+	 */
+	if (status & PECI_INT_TIMEOUT) {
+		dev_dbg(priv->dev, "PECI_INT_TIMEOUT\n");
+		status_ack |= PECI_INT_TIMEOUT;
+	}
+
+	if (status & PECI_INT_CONNECT) {
+		dev_dbg(priv->dev, "PECI_INT_CONNECT\n");
+		status_ack |= PECI_INT_CONNECT;
+	}
+
+	if (status & PECI_INT_W_FCS_BAD) {
+		dev_dbg(priv->dev, "PECI_INT_W_FCS_BAD\n");
+		status_ack |= PECI_INT_W_FCS_BAD;
+	}
+
+	if (status & PECI_INT_W_FCS_ABORT) {
+		dev_dbg(priv->dev, "PECI_INT_W_FCS_ABORT\n");
+		status_ack |= PECI_INT_W_FCS_ABORT;
+	}
+
+	/**
+	 * All commands should be ended up with a PECI_INT_CMD_DONE bit set
+	 * even in an error case.
+	 */
+	if (status & PECI_INT_CMD_DONE) {
+		dev_dbg(priv->dev, "PECI_INT_CMD_DONE\n");
+		status_ack |= PECI_INT_CMD_DONE;
+		complete(&priv->xfer_complete);
+	}
+
+	regmap_write(priv->regmap, ASPEED_PECI_INT_STS, status_ack);
+	spin_unlock(&priv->lock);
+	return IRQ_HANDLED;
+}
+
+static int aspeed_peci_init_ctrl(struct aspeed_peci *priv)
+{
+	u32 msg_timing, addr_timing, rd_sampling_point;
+	u32 clk_freq, clk_divisor, clk_div_val = 0;
+	int ret;
+
+	priv->clk = devm_clk_get(priv->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(priv->dev, "Failed to get clk source.\n");
+		return PTR_ERR(priv->clk);
+	}
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret) {
+		dev_err(priv->dev, "Failed to enable clock.\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(priv->dev->of_node, "clock-frequency",
+				   &clk_freq);
+	if (ret) {
+		dev_err(priv->dev,
+			"Could not read clock-frequency property.\n");
+		clk_disable_unprepare(priv->clk);
+		return ret;
+	}
+
+	clk_divisor = clk_get_rate(priv->clk) / clk_freq;
+
+	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",
+				   &msg_timing);
+	if (ret || msg_timing > PECI_MSG_TIMING_MAX) {
+		if (!ret)
+			dev_warn(priv->dev,
+				 "Invalid msg-timing : %u, Use default : %u\n",
+				 msg_timing, PECI_MSG_TIMING_DEFAULT);
+		msg_timing = PECI_MSG_TIMING_DEFAULT;
+	}
+
+	ret = of_property_read_u32(priv->dev->of_node, "addr-timing",
+				   &addr_timing);
+	if (ret || addr_timing > PECI_ADDR_TIMING_MAX) {
+		if (!ret)
+			dev_warn(priv->dev,
+				 "Invalid addr-timing : %u, Use default : %u\n",
+				 addr_timing, PECI_ADDR_TIMING_DEFAULT);
+		addr_timing = PECI_ADDR_TIMING_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) {
+		if (!ret)
+			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) {
+		if (!ret)
+			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;
+	}
+
+	regmap_write(priv->regmap, ASPEED_PECI_CTRL,
+		     FIELD_PREP(PECI_CTRL_CLK_DIV_MASK, PECI_CLK_DIV_DEFAULT) |
+		     PECI_CTRL_PECI_CLK_EN);
+
+	/**
+	 * Timing negotiation period setting.
+	 * The unit of the programmed value is 4 times of PECI clock period.
+	 */
+	regmap_write(priv->regmap, ASPEED_PECI_TIMING,
+		     FIELD_PREP(PECI_TIMING_MESSAGE_MASK, msg_timing) |
+		     FIELD_PREP(PECI_TIMING_ADDRESS_MASK, addr_timing));
+
+	/* Clear interrupts */
+	regmap_write(priv->regmap, ASPEED_PECI_INT_STS, PECI_INT_MASK);
+
+	/* Enable interrupts */
+	regmap_write(priv->regmap, ASPEED_PECI_INT_CTRL, PECI_INT_MASK);
+
+	/* Read sampling point and clock speed setting */
+	regmap_write(priv->regmap, ASPEED_PECI_CTRL,
+		     FIELD_PREP(PECI_CTRL_SAMPLING_MASK, rd_sampling_point) |
+		     FIELD_PREP(PECI_CTRL_CLK_DIV_MASK, clk_div_val) |
+		     PECI_CTRL_PECI_EN | PECI_CTRL_PECI_CLK_EN);
+
+	return 0;
+}
+
+static const struct regmap_config aspeed_peci_regmap_config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.max_register = ASPEED_PECI_R_DATA7,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
+	.fast_io = true,
+};
+
+static int aspeed_peci_xfer(struct peci_adapter *adapter,
+			    struct peci_xfer_msg *msg)
+{
+	struct aspeed_peci *priv = peci_get_adapdata(adapter);
+
+	return aspeed_peci_xfer_native(priv, msg);
+}
+
+static int aspeed_peci_probe(struct platform_device *pdev)
+{
+	struct peci_adapter *adapter;
+	struct aspeed_peci *priv;
+	struct resource *res;
+	void __iomem *base;
+	u32 cmd_sts;
+	int ret;
+
+	adapter = peci_alloc_adapter(&pdev->dev, sizeof(*priv));
+	if (!adapter)
+		return -ENOMEM;
+
+	priv = peci_get_adapdata(adapter);
+	priv->adapter = adapter;
+	priv->dev = &pdev->dev;
+	dev_set_drvdata(&pdev->dev, priv);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(base)) {
+		ret = PTR_ERR(base);
+		goto err_put_adapter_dev;
+	}
+
+	priv->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+					     &aspeed_peci_regmap_config);
+	if (IS_ERR(priv->regmap)) {
+		ret = PTR_ERR(priv->regmap);
+		goto err_put_adapter_dev;
+	}
+
+	/**
+	 * We check that the regmap works on this very first access,
+	 * but as this is an MMIO-backed regmap, subsequent regmap
+	 * access is not going to fail and we skip error checks from
+	 * this point.
+	 */
+	ret = regmap_read(priv->regmap, ASPEED_PECI_CMD, &cmd_sts);
+	if (ret) {
+		ret = -EIO;
+		goto err_put_adapter_dev;
+	}
+
+	priv->irq = platform_get_irq(pdev, 0);
+	if (!priv->irq) {
+		ret = -ENODEV;
+		goto err_put_adapter_dev;
+	}
+
+	ret = devm_request_irq(&pdev->dev, priv->irq, aspeed_peci_irq_handler,
+			       0, "peci-aspeed-irq", priv);
+	if (ret)
+		goto err_put_adapter_dev;
+
+	init_completion(&priv->xfer_complete);
+	spin_lock_init(&priv->lock);
+
+	priv->adapter->owner = THIS_MODULE;
+	priv->adapter->dev.of_node = of_node_get(dev_of_node(priv->dev));
+	strlcpy(priv->adapter->name, pdev->name, sizeof(priv->adapter->name));
+	priv->adapter->xfer = aspeed_peci_xfer;
+
+	priv->rst = devm_reset_control_get(&pdev->dev, NULL);
+	if (IS_ERR(priv->rst)) {
+		dev_err(&pdev->dev,
+			"missing or invalid reset controller entry");
+		ret = PTR_ERR(priv->rst);
+		goto err_put_adapter_dev;
+	}
+	reset_control_deassert(priv->rst);
+
+	ret = aspeed_peci_init_ctrl(priv);
+	if (ret)
+		goto err_put_adapter_dev;
+
+	ret = peci_add_adapter(priv->adapter);
+	if (ret)
+		goto err_put_adapter_dev;
+
+	dev_info(&pdev->dev, "peci bus %d registered, irq %d\n",
+		 priv->adapter->nr, priv->irq);
+
+	return 0;
+
+err_put_adapter_dev:
+	put_device(&adapter->dev);
+	return ret;
+}
+
+static int aspeed_peci_remove(struct platform_device *pdev)
+{
+	struct aspeed_peci *priv = dev_get_drvdata(&pdev->dev);
+
+	clk_disable_unprepare(priv->clk);
+	reset_control_assert(priv->rst);
+	peci_del_adapter(priv->adapter);
+	of_node_put(priv->adapter->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");
-- 
2.20.1