Message-id: <1354021236-28596-2-git-send-email-ch.naveen@samsung.com>
Date:	Tue, 27 Nov 2012 18:30:34 +0530
From:	Naveen Krishna Chatradhi <ch.naveen@...sung.com>
To:	linux-arm-kernel@...ts.infradead.org,
	linux-samsung-soc@...r.kernel.org,
	devicetree-discuss@...ts.ozlabs.org, linux-i2c@...r.kernel.org
Cc:	naveenkrishna.ch@...il.com, kgene.kim@...sung.com,
	grant.likely@...retlab.ca, w.sang@...gutronix.de,
	linux-kernel@...r.kernel.org, taeggyun.ko@...sung.com
Subject: [PATCH 1/3] i2c: exynos5: add High Speed I2C controller driver

Adds support for High Speed I2C driver found in Exynos5 and later
SoCs from Samsung. This driver currently supports Auto mode.

Driver only supports Device Tree method.

Signed-off-by: Taekgyun Ko <taeggyun.ko@...sung.com>
Signed-off-by: Naveen Krishna Chatradhi <ch.naveen@...sung.com>
---
 drivers/i2c/busses/Kconfig       |    6 +
 drivers/i2c/busses/Makefile      |    1 +
 drivers/i2c/busses/i2c-exynos5.c |  758 ++++++++++++++++++++++++++++++++++++++
 drivers/i2c/busses/i2c-exynos5.h |   80 ++++
 4 files changed, 845 insertions(+)
 create mode 100644 drivers/i2c/busses/i2c-exynos5.c
 create mode 100644 drivers/i2c/busses/i2c-exynos5.h

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 65dd599..88e8833 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -609,6 +609,12 @@ config I2C_S3C2410
 	  Say Y here to include support for I2C controller in the
 	  Samsung SoCs.
 
+config I2C_EXYNOS5
+	tristate "Exynos5 HS-I2C Driver"
+	help
+	  Say Y here to include support for High Speed I2C controller in the
+	  Exynos5 series SoCs from Samsung.
+
 config I2C_S6000
 	tristate "S6000 I2C support"
 	depends on XTENSA_VARIANT_S6000
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 2d33d62..426b4fd 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -60,6 +60,7 @@ obj-$(CONFIG_I2C_PUV3)		+= i2c-puv3.o
 obj-$(CONFIG_I2C_PXA)		+= i2c-pxa.o
 obj-$(CONFIG_I2C_PXA_PCI)	+= i2c-pxa-pci.o
 obj-$(CONFIG_I2C_S3C2410)	+= i2c-s3c2410.o
+obj-$(CONFIG_I2C_EXYNOS5)	+= i2c-exynos5.o
 obj-$(CONFIG_I2C_S6000)		+= i2c-s6000.o
 obj-$(CONFIG_I2C_SH7760)	+= i2c-sh7760.o
 obj-$(CONFIG_I2C_SH_MOBILE)	+= i2c-sh_mobile.o
diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c
new file mode 100644
index 0000000..5983aa9
--- /dev/null
+++ b/drivers/i2c/busses/i2c-exynos5.c
@@ -0,0 +1,758 @@
+/* linux/drivers/i2c/busses/i2c-exynos5.c
+ *
+ * Copyright (C) 2012 Samsung Electronics Co., Ltd.
+ *
+ * Exynos5 series High Speed I2C controller driver
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/of_i2c.h>
+#include <linux/of_gpio.h>
+
+#include <asm/irq.h>
+#include "i2c-exynos5.h"
+
+#define HSI2C_POLLING 0
+#define HSI2C_FAST_SPD 0
+#define HSI2C_HIGH_SPD 1
+
+/* Max time to wait for bus to become idle after a xfer */
+#define EXYNOS5_I2C_TIMEOUT (msecs_to_jiffies(1000))
+
+struct exynos5_i2c {
+	unsigned int		suspended:1;
+
+	struct i2c_msg		*msg;
+	struct completion	msg_complete;
+	unsigned int		msg_byte_ptr;
+
+	unsigned int		irq;
+
+	void __iomem		*regs;
+	struct clk		*clk;
+	struct device		*dev;
+	struct resource		*ioarea;
+	struct i2c_adapter	adap;
+	unsigned int		bus_number;
+	unsigned int		speed_mode;
+	unsigned int		fast_speed;
+	unsigned int		high_speed;
+	int			operation_mode;
+	int			gpios[2];
+};
+
+static struct platform_device_id exynos5_driver_ids[] = {
+	{
+		.name		= "exynos5-hs-i2c",
+		.driver_data	= 0,
+	}, { },
+};
+MODULE_DEVICE_TABLE(platform, exynos5_driver_ids);
+
+#ifdef CONFIG_OF
+static const struct of_device_id exynos5_i2c_match[] = {
+	{ .compatible = "samsung,exynos5-hs-i2c", .data = (void *)0 },
+	{},
+};
+MODULE_DEVICE_TABLE(of, exynos5_i2c_match);
+#endif
+
+static inline void dump_i2c_register(struct exynos5_i2c *i2c)
+{
+	dev_dbg(i2c->dev, "Register dump(%d) :\n %x\n %x\n %x\n %x\n"
+		" %x\n %x\n %x\n %x\n %x\n"
+		" %x\n %x\n %x\n %x\n %x\n"
+		" %x\n %x\n %x\n %x\n %x\n"
+		" %x\n %x\n %x\n %x\n %x\n"
+		, i2c->suspended
+		, readl(i2c->regs + HSI2C_CTL)
+		, readl(i2c->regs + HSI2C_FIFO_CTL)
+		, readl(i2c->regs + HSI2C_TRAILIG_CTL)
+		, readl(i2c->regs + HSI2C_CLK_CTL)
+		, readl(i2c->regs + HSI2C_CLK_SLOT)
+		, readl(i2c->regs + HSI2C_INT_ENABLE)
+		, readl(i2c->regs + HSI2C_INT_STATUS)
+		, readl(i2c->regs + HSI2C_ERR_STATUS)
+		, readl(i2c->regs + HSI2C_FIFO_STATUS)
+		, readl(i2c->regs + HSI2C_TX_DATA)
+		, readl(i2c->regs + HSI2C_RX_DATA)
+		, readl(i2c->regs + HSI2C_CONF)
+		, readl(i2c->regs + HSI2C_AUTO_CONFING)
+		, readl(i2c->regs + HSI2C_TIMEOUT)
+		, readl(i2c->regs + HSI2C_MANUAL_CMD)
+		, readl(i2c->regs + HSI2C_TRANS_STATUS)
+		, readl(i2c->regs + HSI2C_TIMING_HS1)
+		, readl(i2c->regs + HSI2C_TIMING_HS2)
+		, readl(i2c->regs + HSI2C_TIMING_HS3)
+		, readl(i2c->regs + HSI2C_TIMING_FS1)
+		, readl(i2c->regs + HSI2C_TIMING_FS2)
+		, readl(i2c->regs + HSI2C_TIMING_FS3)
+		, readl(i2c->regs + HSI2C_TIMING_SLA)
+		, readl(i2c->regs + HSI2C_ADDR));
+}
+
+static inline void exynos5_i2c_stop(struct exynos5_i2c *i2c)
+{
+	writel(0, i2c->regs + HSI2C_INT_ENABLE);
+
+	complete(&i2c->msg_complete);
+}
+
+static inline void exynos5_disable_irq(struct exynos5_i2c *i2c)
+{
+	unsigned long tmp = readl(i2c->regs + HSI2C_INT_STATUS);
+
+	writel(tmp, i2c->regs +  HSI2C_INT_STATUS);
+}
+
+static void exynos5_i2c_en_timeout(struct exynos5_i2c *i2c)
+{
+	unsigned long i2c_timeout = readl(i2c->regs + HSI2C_TIMEOUT);
+
+	/* Clear to enable Timeout */
+	i2c_timeout &= ~HSI2C_TIMEOUT_EN;
+	writel(i2c_timeout, i2c->regs + HSI2C_TIMEOUT);
+}
+
+static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id)
+{
+	struct exynos5_i2c *i2c = dev_id;
+	unsigned char byte;
+
+	if (i2c->msg->flags & I2C_M_RD) {
+		while ((readl(i2c->regs + HSI2C_FIFO_STATUS) &
+			0x1000000) == 0) {
+			byte = (unsigned char)readl(i2c->regs + HSI2C_RX_DATA);
+			i2c->msg->buf[i2c->msg_byte_ptr++] = byte;
+		}
+
+		if (i2c->msg_byte_ptr >= i2c->msg->len)
+			exynos5_i2c_stop(i2c);
+	} else {
+		byte = i2c->msg->buf[i2c->msg_byte_ptr++];
+		writel(byte, i2c->regs + HSI2C_TX_DATA);
+
+		if (i2c->msg_byte_ptr >= i2c->msg->len)
+			exynos5_i2c_stop(i2c);
+	}
+
+	exynos5_disable_irq(i2c);
+
+	return IRQ_HANDLED;
+}
+
+static int exynos5_i2c_init(struct exynos5_i2c *i2c);
+
+static int exynos5_i2c_reset(struct exynos5_i2c *i2c)
+{
+	unsigned long usi_ctl;
+
+	usi_ctl = readl(i2c->regs + HSI2C_CTL);
+	usi_ctl |= (1u << 31);
+	writel(usi_ctl, i2c->regs + HSI2C_CTL);
+	usi_ctl = readl(i2c->regs + HSI2C_CTL);
+	usi_ctl &= ~(1u << 31);
+	writel(usi_ctl, i2c->regs + HSI2C_CTL);
+	exynos5_i2c_init(i2c);
+
+	return 0;
+}
+
+static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c,
+			      struct i2c_msg *msgs, int num, int stop)
+{
+	unsigned long timeout;
+	unsigned long trans_status;
+	unsigned long usi_fifo_stat;
+	unsigned long usi_ctl;
+	unsigned long i2c_auto_conf;
+	unsigned long i2c_addr;
+	unsigned long usi_int_en;
+	unsigned long usi_fifo_ctl;
+	unsigned char byte;
+	int ret = 0;
+	int operation_mode = i2c->operation_mode;
+
+	i2c->msg = msgs;
+	i2c->msg_byte_ptr = 0;
+
+	init_completion(&i2c->msg_complete);
+
+	usi_ctl		= readl(i2c->regs + HSI2C_CTL);
+	i2c_auto_conf	= readl(i2c->regs + HSI2C_AUTO_CONFING);
+
+	exynos5_i2c_en_timeout(i2c);
+
+	/* Set default trigger level for TXFIFO and RXFIFO */
+	usi_fifo_ctl = HSI2C_TXFIFO_TRIGGER_LEVEL |
+					HSI2C_RXFIFO_TRIGGER_LEVEL;
+	/* Enable RXFIFO and TXFIFO */
+	usi_fifo_ctl = HSI2C_RXFIFO_EN | HSI2C_TXFIFO_EN;
+
+	writel(usi_fifo_ctl, i2c->regs + HSI2C_FIFO_CTL);
+
+	usi_int_en = 0;
+	if (msgs->flags & I2C_M_RD) {
+		usi_ctl &= ~HSI2C_TXCHON;
+		usi_ctl |= HSI2C_RXCHON;
+
+		i2c_auto_conf |= HSI2C_READ_WRITE;
+
+		usi_int_en |= (HSI2C_INT_RX_ALMOSTFULL_EN |
+					HSI2C_INT_TRAILING_EN);
+	} else {
+		usi_ctl &= ~HSI2C_RXCHON;
+		usi_ctl |= HSI2C_TXCHON;
+
+		i2c_auto_conf &= ~HSI2C_READ_WRITE;
+
+		usi_int_en |= HSI2C_INT_TX_ALMOSTEMPTY_EN;
+	}
+
+	if (stop == 1)
+		i2c_auto_conf |= HSI2C_STOP_AFTER_TRANS;
+	else
+		i2c_auto_conf &= ~HSI2C_STOP_AFTER_TRANS;
+
+
+	i2c_addr = readl(i2c->regs + HSI2C_ADDR);
+
+	/* Clear Slave Address for I2C Master (Auto mode only) */
+	i2c_addr &= ~(0x3ff << 10);
+	/* Clear Slave Address for I2C Slave */
+	i2c_addr &= ~(0x3ff << 0);
+	/* Clear Master ID for I2C Master (Auto and HS mode only) */
+	if (i2c->speed_mode == HSI2C_HIGH_SPD)
+		i2c_addr &= ~(0xff << 24);
+
+	i2c_addr |= ((msgs->addr & 0x7f) << 10);
+	writel(i2c_addr, i2c->regs + HSI2C_ADDR);
+
+	writel(usi_ctl, i2c->regs + HSI2C_CTL);
+
+	/* Clear and set TRANS_LEN */
+	i2c_auto_conf &= ~(0xffff);
+	i2c_auto_conf |= i2c->msg->len;
+	writel(i2c_auto_conf, i2c->regs + HSI2C_AUTO_CONFING);
+
+	/* Start data transfer in Master mode */
+	i2c_auto_conf = readl(i2c->regs + HSI2C_AUTO_CONFING);
+	i2c_auto_conf |= HSI2C_MASTER_RUN;
+	writel(i2c_auto_conf, i2c->regs + HSI2C_AUTO_CONFING);
+
+	/* Enable appropriate interrupts */
+	if (operation_mode != HSI2C_POLLING)
+		writel(usi_int_en, i2c->regs + HSI2C_INT_ENABLE);
+
+	ret = -EAGAIN;
+	if (msgs->flags & I2C_M_RD) {
+		if (operation_mode == HSI2C_POLLING) {
+			timeout = jiffies + EXYNOS5_I2C_TIMEOUT;
+			while (time_before(jiffies, timeout)) {
+				if ((readl(i2c->regs + HSI2C_FIFO_STATUS) &
+					0x1000000) == 0) {
+					byte = (unsigned char)readl
+						(i2c->regs + HSI2C_RX_DATA);
+					i2c->msg->buf[i2c->msg_byte_ptr++]
+						= byte;
+				}
+
+				if (i2c->msg_byte_ptr >= i2c->msg->len) {
+					ret = 0;
+					break;
+				}
+			}
+
+			if (ret == -EAGAIN) {
+				exynos5_i2c_reset(i2c);
+				dev_warn(i2c->dev, "rx timeout\n");
+				return ret;
+			}
+		} else {
+			timeout = wait_for_completion_interruptible_timeout
+				(&i2c->msg_complete, EXYNOS5_I2C_TIMEOUT);
+
+			if (timeout == 0) {
+				exynos5_i2c_reset(i2c);
+				dev_warn(i2c->dev, "rx timeout\n");
+				return ret;
+			}
+
+			ret = 0;
+		}
+	} else {
+		if (operation_mode == HSI2C_POLLING) {
+			timeout = jiffies + EXYNOS5_I2C_TIMEOUT;
+			while (time_before(jiffies, timeout) &&
+				(i2c->msg_byte_ptr < i2c->msg->len)) {
+				if ((readl(i2c->regs + HSI2C_FIFO_STATUS)
+					& 0x7f) < 64) {
+					byte = i2c->msg->buf
+						[i2c->msg_byte_ptr++];
+					writel(byte,
+						i2c->regs + HSI2C_TX_DATA);
+				}
+			}
+		} else {
+			timeout = wait_for_completion_interruptible_timeout
+				(&i2c->msg_complete, EXYNOS5_I2C_TIMEOUT);
+
+			if (timeout == 0) {
+				exynos5_i2c_reset(i2c);
+				dev_warn(i2c->dev, "tx timeout\n");
+				return ret;
+			}
+
+			timeout = jiffies + timeout;
+		}
+		while (time_before(jiffies, timeout)) {
+			usi_fifo_stat = readl(i2c->regs + HSI2C_FIFO_STATUS);
+			trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS);
+			if ((usi_fifo_stat == HSI2C_FIFO_EMPTY) &&
+				((trans_status == 0) ||
+				((stop == 0) &&
+				(trans_status == 0x20000)))) {
+				ret = 0;
+				break;
+			}
+		}
+		if (ret == -EAGAIN) {
+			exynos5_i2c_reset(i2c);
+			dev_warn(i2c->dev, "tx timeout\n");
+			return ret;
+		}
+	}
+
+	return ret;
+}
+
+static int exynos5_i2c_xfer(struct i2c_adapter *adap,
+			struct i2c_msg *msgs, int num)
+{
+	struct exynos5_i2c *i2c = (struct exynos5_i2c *)adap->algo_data;
+	int retry, i;
+	int ret;
+	int stop = 0;
+	struct i2c_msg *msgs_ptr = msgs;
+
+	if (i2c->suspended) {
+		dev_err(i2c->dev, "HS-I2C is not initialzed.\n");
+		return -EIO;
+	}
+
+	clk_prepare_enable(i2c->clk);
+
+	for (retry = 0; retry < adap->retries; retry++) {
+		for (i = 0; i < num; i++) {
+			if (i == num - 1)
+				stop = 1;
+			ret = exynos5_i2c_xfer_msg(i2c, msgs_ptr, 1, stop);
+			msgs_ptr++;
+
+			if (ret == -EAGAIN) {
+				msgs_ptr = msgs;
+				stop = 0;
+				break;
+			}
+		}
+		if (i == num) {
+			clk_disable_unprepare(i2c->clk);
+			return num;
+		}
+
+		dev_dbg(i2c->dev, "retrying transfer (%d)\n", retry);
+
+		udelay(100);
+	}
+
+	clk_disable_unprepare(i2c->clk);
+
+	return -EREMOTEIO;
+}
+
+static u32 exynos5_i2c_func(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm exynos5_i2c_algorithm = {
+	.master_xfer		= exynos5_i2c_xfer,
+	.functionality		= exynos5_i2c_func,
+};
+
+static int exynos5_i2c_set_timing(struct exynos5_i2c *i2c)
+{
+	unsigned long i2c_timing_s1;
+	unsigned long i2c_timing_s2;
+	unsigned long i2c_timing_s3;
+	unsigned long i2c_timing_sla;
+	unsigned int op_clk;
+	unsigned int clkin = clk_get_rate(i2c->clk);
+	unsigned int n_clkdiv;
+	unsigned int t_start_su, t_start_hd;
+	unsigned int t_stop_su;
+	unsigned int t_data_su, t_data_hd;
+	unsigned int t_scl_l, t_scl_h;
+	unsigned int t_sr_release;
+	unsigned int t_ftl_cycle;
+	unsigned int i = 0, utemp0 = 0, utemp1 = 0, utemp2 = 0;
+
+	if (i2c->speed_mode == HSI2C_HIGH_SPD)
+		op_clk = i2c->high_speed;
+	else
+		op_clk = i2c->fast_speed;
+
+	/* FPCLK / FI2C =
+	 * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + 2 * FLT_CYCLE
+	 * uTemp0 = (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2)
+	 * uTemp1 = (TSCLK_L + TSCLK_H + 2)
+	 * uTemp2 = TSCLK_L + TSCLK_H
+	*/
+	t_ftl_cycle = (readl(i2c->regs + HSI2C_CONF) >> 16) & 0x7;
+	utemp0 = (clkin / op_clk) - 8 - 2 * t_ftl_cycle;
+
+	/* CLK_DIV max is 256 */
+	for (i = 0; i < 256; i++) {
+		utemp1 = utemp0 / (i + 1);
+		/* SCLK_L/H max is 256 / 2 */
+		if (utemp1 < 128) {
+			utemp2 = utemp1 - 2;
+			break;
+		}
+	}
+
+	n_clkdiv = i;
+	t_scl_l = utemp2 / 2;
+	t_scl_h = utemp2 / 2;
+	t_start_su = t_scl_l;
+	t_start_hd = t_scl_l;
+	t_stop_su = t_scl_l;
+	t_data_su = t_scl_l / 2;
+	t_data_hd = t_scl_l / 2;
+	t_sr_release = utemp2;
+
+	i2c_timing_s1 = t_start_su << 24 | t_start_hd << 16 | t_stop_su << 8;
+	i2c_timing_s2 = t_data_su << 24 | t_scl_l << 8 | t_scl_h << 0;
+	i2c_timing_s3 = n_clkdiv << 16 | t_sr_release << 0;
+	i2c_timing_sla = t_data_hd << 0;
+
+	dev_dbg(i2c->dev, "tSTART_SU: %X, tSTART_HD: %X, tSTOP_SU: %X\n",
+		t_start_su, t_start_hd, t_stop_su);
+	dev_dbg(i2c->dev, "tDATA_SU: %X, tSCL_L: %X, tSCL_H: %X\n",
+		t_data_su, t_scl_l, t_scl_h);
+	dev_dbg(i2c->dev, "nClkDiv: %X, tSR_RELEASE: %X\n",
+		n_clkdiv, t_sr_release);
+	dev_dbg(i2c->dev, "tDATA_HD: %X\n", t_data_hd);
+
+	if (i2c->speed_mode == HSI2C_HIGH_SPD) {
+		writel(i2c_timing_s1, i2c->regs + HSI2C_TIMING_HS1);
+		writel(i2c_timing_s2, i2c->regs + HSI2C_TIMING_HS2);
+		writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_HS3);
+	} else {
+		writel(i2c_timing_s1, i2c->regs + HSI2C_TIMING_FS1);
+		writel(i2c_timing_s2, i2c->regs + HSI2C_TIMING_FS2);
+		writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_FS3);
+	}
+	writel(i2c_timing_sla, i2c->regs + HSI2C_TIMING_SLA);
+
+	return 0;
+}
+
+#ifdef CONFIG_OF
+static int exynos5_i2c_parse_dt_gpio(struct exynos5_i2c *i2c)
+{
+	int idx, gpio, ret;
+
+	for (idx = 0; idx < 2; idx++) {
+		gpio = of_get_gpio(i2c->dev->of_node, idx);
+		if (!gpio_is_valid(gpio)) {
+			dev_err(i2c->dev, "invalid gpio[%d]: %d\n", idx, gpio);
+			goto free_gpio;
+		}
+		i2c->gpios[idx] = gpio;
+
+		ret = gpio_request(gpio, "hsi2c-bus");
+		if (ret) {
+			dev_err(i2c->dev, "gpio [%d] request failed\n", gpio);
+			goto free_gpio;
+		}
+	}
+	return 0;
+
+free_gpio:
+	while (--idx >= 0)
+		gpio_free(i2c->gpios[idx]);
+	return -EINVAL;
+}
+
+static void exynos5_i2c_dt_gpio_free(struct exynos5_i2c *i2c)
+{
+	unsigned int idx;
+
+	for (idx = 0; idx < 2; idx++)
+		gpio_free(i2c->gpios[idx]);
+}
+#else
+static int exynos5_i2c_parse_dt_gpio(struct exynos5_i2c *i2c)
+{
+	return 0;
+}
+
+static void exynos5_i2c_dt_gpio_free(struct exynos5_i2c *i2c)
+{
+}
+#endif
+
+static int exynos5_i2c_init(struct exynos5_i2c *i2c)
+{
+	unsigned long usi_ctl = HSI2C_FUNC_MODE_I2C | HSI2C_MASTER;
+	unsigned long usi_trailing_ctl = HSI2C_TRAILING_COUNT;
+	unsigned long i2c_conf = readl(i2c->regs + HSI2C_CONF);
+
+	if (exynos5_i2c_parse_dt_gpio(i2c))
+		return -EINVAL;
+
+	writel(usi_ctl, i2c->regs + HSI2C_CTL);
+
+	writel(usi_trailing_ctl, i2c->regs + HSI2C_TRAILIG_CTL);
+
+	exynos5_i2c_set_timing(i2c);
+
+	if (i2c->speed_mode == HSI2C_HIGH_SPD) {
+		i2c_conf |= HSI2C_HS_MODE;
+		writel(i2c_conf, i2c->regs + HSI2C_CONF);
+	}
+
+	return 0;
+}
+
+static int exynos5_i2c_probe(struct platform_device *pdev)
+{
+	struct exynos5_i2c *i2c;
+	struct resource *res;
+	int ret;
+
+	i2c = devm_kzalloc(&pdev->dev, sizeof(struct exynos5_i2c), GFP_KERNEL);
+	if (!i2c) {
+		dev_err(&pdev->dev, "no memory for state\n");
+		return -ENOMEM;
+	}
+
+	if (pdev->dev.of_node) {
+		/* i2c bus number is dynamically assigned */
+		i2c->bus_number = -1;
+
+		if (of_property_read_u32(pdev->dev.of_node,
+				"samsung,hsi2c-speed-mode", &i2c->speed_mode))
+			i2c->speed_mode = 1;
+		if (!of_property_read_u32(pdev->dev.of_node,
+				"samsung,hsi2c-hs-clk", &i2c->high_speed))
+			i2c->high_speed = 2500000;
+		if (!of_property_read_u32(pdev->dev.of_node,
+				"samsung,hsi2c-fs-clk", &i2c->fast_speed))
+			i2c->fast_speed = 400000;
+	} else {
+		dev_err(&pdev->dev, "no device node\n");
+		return -ENOENT;
+	}
+
+	strlcpy(i2c->adap.name, "exynos5250-i2c", sizeof(i2c->adap.name));
+	i2c->adap.owner   = THIS_MODULE;
+	i2c->adap.algo    = &exynos5_i2c_algorithm;
+	i2c->adap.retries = 2;
+	i2c->adap.class   = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+
+	i2c->dev = &pdev->dev;
+	i2c->clk = clk_get(&pdev->dev, "hsi2c");
+	if (IS_ERR(i2c->clk)) {
+		dev_err(&pdev->dev, "cannot get clock\n");
+		ret = -ENOENT;
+		goto err_noclk;
+	}
+
+	clk_prepare_enable(i2c->clk);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res == NULL) {
+		dev_err(&pdev->dev, "cannot find HS-I2C IO resource\n");
+		ret = -ENOENT;
+		goto err_clk;
+	}
+
+	i2c->ioarea = request_mem_region(res->start, resource_size(res),
+					 pdev->name);
+
+	if (i2c->ioarea == NULL) {
+		dev_err(&pdev->dev, "cannot request HS-I2C IO\n");
+		ret = -ENXIO;
+		goto err_clk;
+	}
+
+	i2c->regs = ioremap(res->start, resource_size(res));
+
+	if (i2c->regs == NULL) {
+		dev_err(&pdev->dev, "cannot map HS-I2C IO\n");
+		ret = -ENXIO;
+		goto err_ioarea;
+	}
+
+	dev_dbg(&pdev->dev, "registers %p (%p, %p)\n",
+		i2c->regs, i2c->ioarea, res);
+
+	i2c->adap.algo_data = i2c;
+	i2c->adap.dev.parent = &pdev->dev;
+
+	ret = exynos5_i2c_init(i2c);
+	if (ret != 0)
+		goto err_iomap;
+
+	i2c->irq = ret = platform_get_irq(pdev, 0);
+	if (ret <= 0) {
+		dev_err(&pdev->dev, "cannot find HS-I2C IRQ\n");
+		goto err_iomap;
+	}
+
+	ret = request_irq(i2c->irq, exynos5_i2c_irq, IRQF_DISABLED,
+			  dev_name(&pdev->dev), i2c);
+
+	if (ret != 0) {
+		dev_err(&pdev->dev, "cannot request HS-I2C IRQ %d\n", i2c->irq);
+		goto err_iomap;
+	}
+
+	i2c->adap.nr = i2c->bus_number;
+	i2c->adap.dev.of_node = pdev->dev.of_node;
+
+	ret = i2c_add_numbered_adapter(&i2c->adap);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to add bus to i2c core\n");
+		goto err_irq;
+	}
+
+	of_i2c_register_devices(&i2c->adap);
+	platform_set_drvdata(pdev, i2c);
+
+	dev_info(&pdev->dev, "%s: Exynos5 HS-I2C adapter\n",
+		dev_name(&i2c->adap.dev));
+	clk_disable_unprepare(i2c->clk);
+	return 0;
+
+ err_irq:
+	free_irq(i2c->irq, i2c);
+
+ err_iomap:
+	iounmap(i2c->regs);
+
+ err_ioarea:
+	release_resource(i2c->ioarea);
+	kfree(i2c->ioarea);
+
+ err_clk:
+	clk_disable_unprepare(i2c->clk);
+	clk_put(i2c->clk);
+
+ err_noclk:
+	return ret;
+}
+
+static int exynos5_i2c_remove(struct platform_device *pdev)
+{
+	struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&i2c->adap);
+	free_irq(i2c->irq, i2c);
+
+	clk_disable_unprepare(i2c->clk);
+	clk_put(i2c->clk);
+
+	iounmap(i2c->regs);
+
+	release_resource(i2c->ioarea);
+	exynos5_i2c_dt_gpio_free(i2c);
+	kfree(i2c->ioarea);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int exynos5_i2c_suspend_noirq(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+
+	i2c_lock_adapter(&i2c->adap);
+	i2c->suspended = 1;
+	i2c_unlock_adapter(&i2c->adap);
+
+	return 0;
+}
+
+static int exynos5_i2c_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+
+	i2c_lock_adapter(&i2c->adap);
+	clk_prepare_enable(i2c->clk);
+	exynos5_i2c_init(i2c);
+	clk_disable_unprepare(i2c->clk);
+	i2c->suspended = 0;
+	i2c_unlock_adapter(&i2c->adap);
+
+	return 0;
+}
+
+static const struct dev_pm_ops exynos5_i2c_dev_pm_ops = {
+	.suspend_noirq	= exynos5_i2c_suspend_noirq,
+	.resume_noirq	= exynos5_i2c_resume,
+};
+
+#define EXYNOS5_DEV_PM_OPS (&exynos5_i2c_dev_pm_ops)
+#else
+#define EXYNOS5_DEV_PM_OPS NULL
+#endif
+
+static struct platform_driver exynos5_i2c_driver = {
+	.probe		= exynos5_i2c_probe,
+	.remove		= exynos5_i2c_remove,
+	.id_table	= exynos5_driver_ids,
+	.driver		= {
+		.owner	= THIS_MODULE,
+		.name	= "exynos5-i2c",
+		.pm	= EXYNOS5_DEV_PM_OPS,
+		.of_match_table = of_match_ptr(exynos5_i2c_match),
+	},
+};
+
+static int __init i2c_adap_exynos5_init(void)
+{
+	return platform_driver_register(&exynos5_i2c_driver);
+}
+subsys_initcall(i2c_adap_exynos5_init);
+
+static void __exit i2c_adap_exynos5_exit(void)
+{
+	platform_driver_unregister(&exynos5_i2c_driver);
+}
+module_exit(i2c_adap_exynos5_exit);
+
+MODULE_DESCRIPTION("Exynos5 HS-I2C Bus driver");
+MODULE_AUTHOR("Taekgyun Ko, <taeggyun.ko@...sung.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-exynos5.h b/drivers/i2c/busses/i2c-exynos5.h
new file mode 100644
index 0000000..063051e
--- /dev/null
+++ b/drivers/i2c/busses/i2c-exynos5.h
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2012 Samsung Electronics Co., Ltd.
+ *
+ * Exynos5 series HS-I2C Controller
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#ifndef __ASM_ARCH_REGS_HS_IIC_H
+#define __ASM_ARCH_REGS_HS_IIC_H __FILE__
+
+/*
+ *	Register Map
+ */
+#define HSI2C_CTL				0x00
+#define HSI2C_FIFO_CTL				0x04
+#define HSI2C_TRAILIG_CTL			0x08
+#define HSI2C_CLK_CTL				0x0C
+#define HSI2C_CLK_SLOT				0x10
+#define HSI2C_INT_ENABLE			0x20
+#define HSI2C_INT_STATUS			0x24
+#define HSI2C_ERR_STATUS			0x2C
+#define HSI2C_FIFO_STATUS			0x30
+#define HSI2C_TX_DATA				0x34
+#define HSI2C_RX_DATA				0x38
+#define HSI2C_CONF				0x40
+#define HSI2C_AUTO_CONFING			0x44
+#define HSI2C_TIMEOUT				0x48
+#define HSI2C_MANUAL_CMD			0x4C
+#define HSI2C_TRANS_STATUS			0x50
+#define HSI2C_TIMING_HS1			0x54
+#define HSI2C_TIMING_HS2			0x58
+#define HSI2C_TIMING_HS3			0x5C
+#define HSI2C_TIMING_FS1			0x60
+#define HSI2C_TIMING_FS2			0x64
+#define HSI2C_TIMING_FS3			0x68
+#define HSI2C_TIMING_SLA			0x6C
+#define HSI2C_ADDR				0x70
+
+/* I2C_CTL Register */
+#define HSI2C_FUNC_MODE_I2C			(1u << 0)
+#define HSI2C_MASTER				(1u << 3)
+#define HSI2C_RXCHON				(1u << 6)
+#define HSI2C_TXCHON				(1u << 7)
+
+/* I2C_FIFO_CTL Register */
+#define HSI2C_RXFIFO_EN				(1u << 0)
+#define HSI2C_TXFIFO_EN				(1u << 1)
+#define HSI2C_TXFIFO_TRIGGER_LEVEL		(0x20 << 16)
+#define HSI2C_RXFIFO_TRIGGER_LEVEL		(0x20 << 4)
+
+/* I2C_TRAILING_CTL Register */
+#define HSI2C_TRAILING_COUNT			(0xf)
+
+/* I2C_INT_EN Register */
+#define HSI2C_INT_TX_ALMOSTEMPTY_EN		(1u << 0) /* For TX FIFO */
+#define HSI2C_INT_RX_ALMOSTFULL_EN		(1u << 1) /* For RX FIFO */
+#define HSI2C_INT_TRAILING_EN			(1u << 6)
+
+/* I2C_CONF Register */
+#define HSI2C_AUTO_MODE				(1u << 31)
+#define HSI2C_10BIT_ADDR_MODE			(1u << 30)
+#define HSI2C_HS_MODE				(1u << 29)
+
+/* I2C_AUTO_CONF Register */
+#define HSI2C_READ_WRITE			(1u << 16)
+#define HSI2C_STOP_AFTER_TRANS			(1u << 17)
+#define HSI2C_MASTER_RUN			(1u << 31)
+
+/* I2C_TIMEOUT Register */
+#define HSI2C_TIMEOUT_EN			(1u << 31)
+
+#define HSI2C_FIFO_EMPTY			(0x1000100)
+
+#define HSI2C_FS_BPS				400000
+#define HSI2C_HS_BPS				2500000
+
+#endif /* __ASM_ARCH_REGS_HS_IIC_H */
-- 
1.7.9.5

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