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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-18 03:10:19 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-18 03:10:19 +0300
commit02e4c627d862427653fc088ce299746ea7d85600 (patch)
treee756f329f8f5e4546c9f62c3493903895227f5b6 /drivers/i2c
parent4b0e976c663e808822adf51274f948e8a4986f06 (diff)
parentead9a638c8f7a4f6471a130c854afafeccbb0824 (diff)
downloadlinux-02e4c627d862427653fc088ce299746ea7d85600.tar.xz
Merge branch 'for-linus/2639/i2c-1' of git://git.fluff.org/bjdooks/linux
* 'for-linus/2639/i2c-1' of git://git.fluff.org/bjdooks/linux: i2c-mpc: Add support for 64bit system i2c: add driver for Freescale i.MX28 i2c: tegra: Add i2c support
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/Kconfig19
-rw-r--r--drivers/i2c/busses/Makefile2
-rw-r--r--drivers/i2c/busses/i2c-mxs.c412
-rw-r--r--drivers/i2c/busses/i2c-tegra.c700
4 files changed, 1132 insertions, 1 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index cbfcf6fb4a61..230601e8853f 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -433,7 +433,7 @@ config I2C_IXP2000
config I2C_MPC
tristate "MPC107/824x/85xx/512x/52xx/83xx/86xx"
- depends on PPC32
+ depends on PPC
help
If you say yes to this option, support will be included for the
built-in I2C interface on the MPC107, Tsi107, MPC512x, MPC52xx,
@@ -452,6 +452,16 @@ config I2C_MV64XXX
This driver can also be built as a module. If so, the module
will be called i2c-mv64xxx.
+config I2C_MXS
+ tristate "Freescale i.MX28 I2C interface"
+ depends on SOC_IMX28
+ help
+ Say Y here if you want to use the I2C bus controller on
+ the Freescale i.MX28 processors.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-mxs.
+
config I2C_NOMADIK
tristate "ST-Ericsson Nomadik/Ux500 I2C Controller"
depends on PLAT_NOMADIK
@@ -618,6 +628,13 @@ config I2C_STU300
This driver can also be built as a module. If so, the module
will be called i2c-stu300.
+config I2C_TEGRA
+ tristate "NVIDIA Tegra internal I2C controller"
+ depends on ARCH_TEGRA
+ help
+ If you say yes to this option, support will be included for the
+ I2C controller embedded in NVIDIA Tegra SOCs
+
config I2C_VERSATILE
tristate "ARM Versatile/Realview I2C bus support"
depends on ARCH_VERSATILE || ARCH_REALVIEW || ARCH_VEXPRESS
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index a83966acc5ab..3878c959d4fa 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o
obj-$(CONFIG_I2C_IXP2000) += i2c-ixp2000.o
obj-$(CONFIG_I2C_MPC) += i2c-mpc.o
obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o
+obj-$(CONFIG_I2C_MXS) += i2c-mxs.o
obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o
obj-$(CONFIG_I2C_NUC900) += i2c-nuc900.o
obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o
@@ -59,6 +60,7 @@ obj-$(CONFIG_I2C_SH7760) += i2c-sh7760.o
obj-$(CONFIG_I2C_SH_MOBILE) += i2c-sh_mobile.o
obj-$(CONFIG_I2C_SIMTEC) += i2c-simtec.o
obj-$(CONFIG_I2C_STU300) += i2c-stu300.o
+obj-$(CONFIG_I2C_TEGRA) += i2c-tegra.o
obj-$(CONFIG_I2C_VERSATILE) += i2c-versatile.o
obj-$(CONFIG_I2C_OCTEON) += i2c-octeon.o
obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c
new file mode 100644
index 000000000000..8022e2390a5a
--- /dev/null
+++ b/drivers/i2c/busses/i2c-mxs.c
@@ -0,0 +1,412 @@
+/*
+ * Freescale MXS I2C bus driver
+ *
+ * Copyright (C) 2011 Wolfram Sang, Pengutronix e.K.
+ *
+ * based on a (non-working) driver which was:
+ *
+ * Copyright (C) 2009-2010 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * TODO: add dma-support if platform-support for it is available
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/completion.h>
+#include <linux/platform_device.h>
+#include <linux/jiffies.h>
+#include <linux/io.h>
+
+#include <mach/common.h>
+
+#define DRIVER_NAME "mxs-i2c"
+
+#define MXS_I2C_CTRL0 (0x00)
+#define MXS_I2C_CTRL0_SET (0x04)
+
+#define MXS_I2C_CTRL0_SFTRST 0x80000000
+#define MXS_I2C_CTRL0_SEND_NAK_ON_LAST 0x02000000
+#define MXS_I2C_CTRL0_RETAIN_CLOCK 0x00200000
+#define MXS_I2C_CTRL0_POST_SEND_STOP 0x00100000
+#define MXS_I2C_CTRL0_PRE_SEND_START 0x00080000
+#define MXS_I2C_CTRL0_MASTER_MODE 0x00020000
+#define MXS_I2C_CTRL0_DIRECTION 0x00010000
+#define MXS_I2C_CTRL0_XFER_COUNT(v) ((v) & 0x0000FFFF)
+
+#define MXS_I2C_CTRL1 (0x40)
+#define MXS_I2C_CTRL1_SET (0x44)
+#define MXS_I2C_CTRL1_CLR (0x48)
+
+#define MXS_I2C_CTRL1_BUS_FREE_IRQ 0x80
+#define MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ 0x40
+#define MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ 0x20
+#define MXS_I2C_CTRL1_OVERSIZE_XFER_TERM_IRQ 0x10
+#define MXS_I2C_CTRL1_EARLY_TERM_IRQ 0x08
+#define MXS_I2C_CTRL1_MASTER_LOSS_IRQ 0x04
+#define MXS_I2C_CTRL1_SLAVE_STOP_IRQ 0x02
+#define MXS_I2C_CTRL1_SLAVE_IRQ 0x01
+
+#define MXS_I2C_IRQ_MASK (MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ | \
+ MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ | \
+ MXS_I2C_CTRL1_EARLY_TERM_IRQ | \
+ MXS_I2C_CTRL1_MASTER_LOSS_IRQ | \
+ MXS_I2C_CTRL1_SLAVE_STOP_IRQ | \
+ MXS_I2C_CTRL1_SLAVE_IRQ)
+
+#define MXS_I2C_QUEUECTRL (0x60)
+#define MXS_I2C_QUEUECTRL_SET (0x64)
+#define MXS_I2C_QUEUECTRL_CLR (0x68)
+
+#define MXS_I2C_QUEUECTRL_QUEUE_RUN 0x20
+#define MXS_I2C_QUEUECTRL_PIO_QUEUE_MODE 0x04
+
+#define MXS_I2C_QUEUESTAT (0x70)
+#define MXS_I2C_QUEUESTAT_RD_QUEUE_EMPTY 0x00002000
+
+#define MXS_I2C_QUEUECMD (0x80)
+
+#define MXS_I2C_QUEUEDATA (0x90)
+
+#define MXS_I2C_DATA (0xa0)
+
+
+#define MXS_CMD_I2C_SELECT (MXS_I2C_CTRL0_RETAIN_CLOCK | \
+ MXS_I2C_CTRL0_PRE_SEND_START | \
+ MXS_I2C_CTRL0_MASTER_MODE | \
+ MXS_I2C_CTRL0_DIRECTION | \
+ MXS_I2C_CTRL0_XFER_COUNT(1))
+
+#define MXS_CMD_I2C_WRITE (MXS_I2C_CTRL0_PRE_SEND_START | \
+ MXS_I2C_CTRL0_MASTER_MODE | \
+ MXS_I2C_CTRL0_DIRECTION)
+
+#define MXS_CMD_I2C_READ (MXS_I2C_CTRL0_SEND_NAK_ON_LAST | \
+ MXS_I2C_CTRL0_MASTER_MODE)
+
+/**
+ * struct mxs_i2c_dev - per device, private MXS-I2C data
+ *
+ * @dev: driver model device node
+ * @regs: IO registers pointer
+ * @cmd_complete: completion object for transaction wait
+ * @cmd_err: error code for last transaction
+ * @adapter: i2c subsystem adapter node
+ */
+struct mxs_i2c_dev {
+ struct device *dev;
+ void __iomem *regs;
+ struct completion cmd_complete;
+ u32 cmd_err;
+ struct i2c_adapter adapter;
+};
+
+/*
+ * TODO: check if calls to here are really needed. If not, we could get rid of
+ * mxs_reset_block and the mach-dependency. Needs an I2C analyzer, probably.
+ */
+static void mxs_i2c_reset(struct mxs_i2c_dev *i2c)
+{
+ mxs_reset_block(i2c->regs);
+ writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET);
+}
+
+static void mxs_i2c_pioq_setup_read(struct mxs_i2c_dev *i2c, u8 addr, int len,
+ int flags)
+{
+ u32 data;
+
+ writel(MXS_CMD_I2C_SELECT, i2c->regs + MXS_I2C_QUEUECMD);
+
+ data = (addr << 1) | I2C_SMBUS_READ;
+ writel(data, i2c->regs + MXS_I2C_DATA);
+
+ data = MXS_CMD_I2C_READ | MXS_I2C_CTRL0_XFER_COUNT(len) | flags;
+ writel(data, i2c->regs + MXS_I2C_QUEUECMD);
+}
+
+static void mxs_i2c_pioq_setup_write(struct mxs_i2c_dev *i2c,
+ u8 addr, u8 *buf, int len, int flags)
+{
+ u32 data;
+ int i, shifts_left;
+
+ data = MXS_CMD_I2C_WRITE | MXS_I2C_CTRL0_XFER_COUNT(len + 1) | flags;
+ writel(data, i2c->regs + MXS_I2C_QUEUECMD);
+
+ /*
+ * We have to copy the slave address (u8) and buffer (arbitrary number
+ * of u8) into the data register (u32). To achieve that, the u8 are put
+ * into the MSBs of 'data' which is then shifted for the next u8. When
+ * apropriate, 'data' is written to MXS_I2C_DATA. So, the first u32
+ * looks like this:
+ *
+ * 3 2 1 0
+ * 10987654|32109876|54321098|76543210
+ * --------+--------+--------+--------
+ * buffer+2|buffer+1|buffer+0|slave_addr
+ */
+
+ data = ((addr << 1) | I2C_SMBUS_WRITE) << 24;
+
+ for (i = 0; i < len; i++) {
+ data >>= 8;
+ data |= buf[i] << 24;
+ if ((i & 3) == 2)
+ writel(data, i2c->regs + MXS_I2C_DATA);
+ }
+
+ /* Write out the remaining bytes if any */
+ shifts_left = 24 - (i & 3) * 8;
+ if (shifts_left)
+ writel(data >> shifts_left, i2c->regs + MXS_I2C_DATA);
+}
+
+/*
+ * TODO: should be replaceable with a waitqueue and RD_QUEUE_IRQ (setting the
+ * rd_threshold to 1). Couldn't get this to work, though.
+ */
+static int mxs_i2c_wait_for_data(struct mxs_i2c_dev *i2c)
+{
+ unsigned long timeout = jiffies + msecs_to_jiffies(1000);
+
+ while (readl(i2c->regs + MXS_I2C_QUEUESTAT)
+ & MXS_I2C_QUEUESTAT_RD_QUEUE_EMPTY) {
+ if (time_after(jiffies, timeout))
+ return -ETIMEDOUT;
+ cond_resched();
+ }
+
+ return 0;
+}
+
+static int mxs_i2c_finish_read(struct mxs_i2c_dev *i2c, u8 *buf, int len)
+{
+ u32 data;
+ int i;
+
+ for (i = 0; i < len; i++) {
+ if ((i & 3) == 0) {
+ if (mxs_i2c_wait_for_data(i2c))
+ return -ETIMEDOUT;
+ data = readl(i2c->regs + MXS_I2C_QUEUEDATA);
+ }
+ buf[i] = data & 0xff;
+ data >>= 8;
+ }
+
+ return 0;
+}
+
+/*
+ * Low level master read/write transaction.
+ */
+static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg,
+ int stop)
+{
+ struct mxs_i2c_dev *i2c = i2c_get_adapdata(adap);
+ int ret;
+ int flags;
+
+ init_completion(&i2c->cmd_complete);
+
+ dev_dbg(i2c->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
+ msg->addr, msg->len, msg->flags, stop);
+
+ if (msg->len == 0)
+ return -EINVAL;
+
+ flags = stop ? MXS_I2C_CTRL0_POST_SEND_STOP : 0;
+
+ if (msg->flags & I2C_M_RD)
+ mxs_i2c_pioq_setup_read(i2c, msg->addr, msg->len, flags);
+ else
+ mxs_i2c_pioq_setup_write(i2c, msg->addr, msg->buf, msg->len,
+ flags);
+
+ writel(MXS_I2C_QUEUECTRL_QUEUE_RUN,
+ i2c->regs + MXS_I2C_QUEUECTRL_SET);
+
+ ret = wait_for_completion_timeout(&i2c->cmd_complete,
+ msecs_to_jiffies(1000));
+ if (ret == 0)
+ goto timeout;
+
+ if ((!i2c->cmd_err) && (msg->flags & I2C_M_RD)) {
+ ret = mxs_i2c_finish_read(i2c, msg->buf, msg->len);
+ if (ret)
+ goto timeout;
+ }
+
+ if (i2c->cmd_err == -ENXIO)
+ mxs_i2c_reset(i2c);
+
+ dev_dbg(i2c->dev, "Done with err=%d\n", i2c->cmd_err);
+
+ return i2c->cmd_err;
+
+timeout:
+ dev_dbg(i2c->dev, "Timeout!\n");
+ mxs_i2c_reset(i2c);
+ return -ETIMEDOUT;
+}
+
+static int mxs_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
+ int num)
+{
+ int i;
+ int err;
+
+ for (i = 0; i < num; i++) {
+ err = mxs_i2c_xfer_msg(adap, &msgs[i], i == (num - 1));
+ if (err)
+ return err;
+ }
+
+ return num;
+}
+
+static u32 mxs_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+}
+
+static irqreturn_t mxs_i2c_isr(int this_irq, void *dev_id)
+{
+ struct mxs_i2c_dev *i2c = dev_id;
+ u32 stat = readl(i2c->regs + MXS_I2C_CTRL1) & MXS_I2C_IRQ_MASK;
+
+ if (!stat)
+ return IRQ_NONE;
+
+ if (stat & MXS_I2C_CTRL1_NO_SLAVE_ACK_IRQ)
+ i2c->cmd_err = -ENXIO;
+ else if (stat & (MXS_I2C_CTRL1_EARLY_TERM_IRQ |
+ MXS_I2C_CTRL1_MASTER_LOSS_IRQ |
+ MXS_I2C_CTRL1_SLAVE_STOP_IRQ | MXS_I2C_CTRL1_SLAVE_IRQ))
+ /* MXS_I2C_CTRL1_OVERSIZE_XFER_TERM_IRQ is only for slaves */
+ i2c->cmd_err = -EIO;
+ else
+ i2c->cmd_err = 0;
+
+ complete(&i2c->cmd_complete);
+
+ writel(stat, i2c->regs + MXS_I2C_CTRL1_CLR);
+ return IRQ_HANDLED;
+}
+
+static const struct i2c_algorithm mxs_i2c_algo = {
+ .master_xfer = mxs_i2c_xfer,
+ .functionality = mxs_i2c_func,
+};
+
+static int __devinit mxs_i2c_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct mxs_i2c_dev *i2c;
+ struct i2c_adapter *adap;
+ struct resource *res;
+ resource_size_t res_size;
+ int err, irq;
+
+ i2c = devm_kzalloc(dev, sizeof(struct mxs_i2c_dev), GFP_KERNEL);
+ if (!i2c)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENOENT;
+
+ res_size = resource_size(res);
+ if (!devm_request_mem_region(dev, res->start, res_size, res->name))
+ return -EBUSY;
+
+ i2c->regs = devm_ioremap_nocache(dev, res->start, res_size);
+ if (!i2c->regs)
+ return -EBUSY;
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ err = devm_request_irq(dev, irq, mxs_i2c_isr, 0, dev_name(dev), i2c);
+ if (err)
+ return err;
+
+ i2c->dev = dev;
+ platform_set_drvdata(pdev, i2c);
+
+ /* Do reset to enforce correct startup after pinmuxing */
+ mxs_i2c_reset(i2c);
+ writel(MXS_I2C_QUEUECTRL_PIO_QUEUE_MODE,
+ i2c->regs + MXS_I2C_QUEUECTRL_SET);
+
+ adap = &i2c->adapter;
+ strlcpy(adap->name, "MXS I2C adapter", sizeof(adap->name));
+ adap->owner = THIS_MODULE;
+ adap->algo = &mxs_i2c_algo;
+ adap->dev.parent = dev;
+ adap->nr = pdev->id;
+ i2c_set_adapdata(adap, i2c);
+ err = i2c_add_numbered_adapter(adap);
+ if (err) {
+ dev_err(dev, "Failed to add adapter (%d)\n", err);
+ writel(MXS_I2C_CTRL0_SFTRST,
+ i2c->regs + MXS_I2C_CTRL0_SET);
+ return err;
+ }
+
+ return 0;
+}
+
+static int __devexit mxs_i2c_remove(struct platform_device *pdev)
+{
+ struct mxs_i2c_dev *i2c = platform_get_drvdata(pdev);
+ int ret;
+
+ ret = i2c_del_adapter(&i2c->adapter);
+ if (ret)
+ return -EBUSY;
+
+ writel(MXS_I2C_QUEUECTRL_QUEUE_RUN,
+ i2c->regs + MXS_I2C_QUEUECTRL_CLR);
+ writel(MXS_I2C_CTRL0_SFTRST, i2c->regs + MXS_I2C_CTRL0_SET);
+
+ platform_set_drvdata(pdev, NULL);
+
+ return 0;
+}
+
+static struct platform_driver mxs_i2c_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ },
+ .remove = __devexit_p(mxs_i2c_remove),
+};
+
+static int __init mxs_i2c_init(void)
+{
+ return platform_driver_probe(&mxs_i2c_driver, mxs_i2c_probe);
+}
+subsys_initcall(mxs_i2c_init);
+
+static void __exit mxs_i2c_exit(void)
+{
+ platform_driver_unregister(&mxs_i2c_driver);
+}
+module_exit(mxs_i2c_exit);
+
+MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
+MODULE_DESCRIPTION("MXS I2C Bus Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRIVER_NAME);
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
new file mode 100644
index 000000000000..3921f664c9c3
--- /dev/null
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -0,0 +1,700 @@
+/*
+ * drivers/i2c/busses/i2c-tegra.c
+ *
+ * Copyright (C) 2010 Google, Inc.
+ * Author: Colin Cross <ccross@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/i2c-tegra.h>
+
+#include <asm/unaligned.h>
+
+#include <mach/clk.h>
+
+#define TEGRA_I2C_TIMEOUT (msecs_to_jiffies(1000))
+#define BYTES_PER_FIFO_WORD 4
+
+#define I2C_CNFG 0x000
+#define I2C_CNFG_PACKET_MODE_EN (1<<10)
+#define I2C_CNFG_NEW_MASTER_FSM (1<<11)
+#define I2C_SL_CNFG 0x020
+#define I2C_SL_CNFG_NEWSL (1<<2)
+#define I2C_SL_ADDR1 0x02c
+#define I2C_TX_FIFO 0x050
+#define I2C_RX_FIFO 0x054
+#define I2C_PACKET_TRANSFER_STATUS 0x058
+#define I2C_FIFO_CONTROL 0x05c
+#define I2C_FIFO_CONTROL_TX_FLUSH (1<<1)
+#define I2C_FIFO_CONTROL_RX_FLUSH (1<<0)
+#define I2C_FIFO_CONTROL_TX_TRIG_SHIFT 5
+#define I2C_FIFO_CONTROL_RX_TRIG_SHIFT 2
+#define I2C_FIFO_STATUS 0x060
+#define I2C_FIFO_STATUS_TX_MASK 0xF0
+#define I2C_FIFO_STATUS_TX_SHIFT 4
+#define I2C_FIFO_STATUS_RX_MASK 0x0F
+#define I2C_FIFO_STATUS_RX_SHIFT 0
+#define I2C_INT_MASK 0x064
+#define I2C_INT_STATUS 0x068
+#define I2C_INT_PACKET_XFER_COMPLETE (1<<7)
+#define I2C_INT_ALL_PACKETS_XFER_COMPLETE (1<<6)
+#define I2C_INT_TX_FIFO_OVERFLOW (1<<5)
+#define I2C_INT_RX_FIFO_UNDERFLOW (1<<4)
+#define I2C_INT_NO_ACK (1<<3)
+#define I2C_INT_ARBITRATION_LOST (1<<2)
+#define I2C_INT_TX_FIFO_DATA_REQ (1<<1)
+#define I2C_INT_RX_FIFO_DATA_REQ (1<<0)
+#define I2C_CLK_DIVISOR 0x06c
+
+#define DVC_CTRL_REG1 0x000
+#define DVC_CTRL_REG1_INTR_EN (1<<10)
+#define DVC_CTRL_REG2 0x004
+#define DVC_CTRL_REG3 0x008
+#define DVC_CTRL_REG3_SW_PROG (1<<26)
+#define DVC_CTRL_REG3_I2C_DONE_INTR_EN (1<<30)
+#define DVC_STATUS 0x00c
+#define DVC_STATUS_I2C_DONE_INTR (1<<30)
+
+#define I2C_ERR_NONE 0x00
+#define I2C_ERR_NO_ACK 0x01
+#define I2C_ERR_ARBITRATION_LOST 0x02
+
+#define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
+#define PACKET_HEADER0_PACKET_ID_SHIFT 16
+#define PACKET_HEADER0_CONT_ID_SHIFT 12
+#define PACKET_HEADER0_PROTOCOL_I2C (1<<4)
+
+#define I2C_HEADER_HIGHSPEED_MODE (1<<22)
+#define I2C_HEADER_CONT_ON_NAK (1<<21)
+#define I2C_HEADER_SEND_START_BYTE (1<<20)
+#define I2C_HEADER_READ (1<<19)
+#define I2C_HEADER_10BIT_ADDR (1<<18)
+#define I2C_HEADER_IE_ENABLE (1<<17)
+#define I2C_HEADER_REPEAT_START (1<<16)
+#define I2C_HEADER_MASTER_ADDR_SHIFT 12
+#define I2C_HEADER_SLAVE_ADDR_SHIFT 1
+
+/**
+ * struct tegra_i2c_dev - per device i2c context
+ * @dev: device reference for power management
+ * @adapter: core i2c layer adapter information
+ * @clk: clock reference for i2c controller
+ * @i2c_clk: clock reference for i2c bus
+ * @iomem: memory resource for registers
+ * @base: ioremapped registers cookie
+ * @cont_id: i2c controller id, used for for packet header
+ * @irq: irq number of transfer complete interrupt
+ * @is_dvc: identifies the DVC i2c controller, has a different register layout
+ * @msg_complete: transfer completion notifier
+ * @msg_err: error code for completed message
+ * @msg_buf: pointer to current message data
+ * @msg_buf_remaining: size of unsent data in the message buffer
+ * @msg_read: identifies read transfers
+ * @bus_clk_rate: current i2c bus clock rate
+ * @is_suspended: prevents i2c controller accesses after suspend is called
+ */
+struct tegra_i2c_dev {
+ struct device *dev;
+ struct i2c_adapter adapter;
+ struct clk *clk;
+ struct clk *i2c_clk;
+ struct resource *iomem;
+ void __iomem *base;
+ int cont_id;
+ int irq;
+ int is_dvc;
+ struct completion msg_complete;
+ int msg_err;
+ u8 *msg_buf;
+ size_t msg_buf_remaining;
+ int msg_read;
+ unsigned long bus_clk_rate;
+ bool is_suspended;
+};
+
+static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val, unsigned long reg)
+{
+ writel(val, i2c_dev->base + reg);
+}
+
+static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
+{
+ return readl(i2c_dev->base + reg);
+}
+
+/*
+ * i2c_writel and i2c_readl will offset the register if necessary to talk
+ * to the I2C block inside the DVC block
+ */
+static unsigned long tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev,
+ unsigned long reg)
+{
+ if (i2c_dev->is_dvc)
+ reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40;
+ return reg;
+}
+
+static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
+ unsigned long reg)
+{
+ writel(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
+}
+
+static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
+{
+ return readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
+}
+
+static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data,
+ unsigned long reg, int len)
+{
+ writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
+}
+
+static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data,
+ unsigned long reg, int len)
+{
+ readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
+}
+
+static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask)
+{
+ u32 int_mask = i2c_readl(i2c_dev, I2C_INT_MASK);
+ int_mask &= ~mask;
+ i2c_writel(i2c_dev, int_mask, I2C_INT_MASK);
+}
+
+static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask)
+{
+ u32 int_mask = i2c_readl(i2c_dev, I2C_INT_MASK);
+ int_mask |= mask;
+ i2c_writel(i2c_dev, int_mask, I2C_INT_MASK);
+}
+
+static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev)
+{
+ unsigned long timeout = jiffies + HZ;
+ u32 val = i2c_readl(i2c_dev, I2C_FIFO_CONTROL);
+ val |= I2C_FIFO_CONTROL_TX_FLUSH | I2C_FIFO_CONTROL_RX_FLUSH;
+ i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL);
+
+ while (i2c_readl(i2c_dev, I2C_FIFO_CONTROL) &
+ (I2C_FIFO_CONTROL_TX_FLUSH | I2C_FIFO_CONTROL_RX_FLUSH)) {
+ if (time_after(jiffies, timeout)) {
+ dev_warn(i2c_dev->dev, "timeout waiting for fifo flush\n");
+ return -ETIMEDOUT;
+ }
+ msleep(1);
+ }
+ return 0;
+}
+
+static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
+{
+ u32 val;
+ int rx_fifo_avail;
+ u8 *buf = i2c_dev->msg_buf;
+ size_t buf_remaining = i2c_dev->msg_buf_remaining;
+ int words_to_transfer;
+
+ val = i2c_readl(i2c_dev, I2C_FIFO_STATUS);
+ rx_fifo_avail = (val & I2C_FIFO_STATUS_RX_MASK) >>
+ I2C_FIFO_STATUS_RX_SHIFT;
+
+ /* Rounds down to not include partial word at the end of buf */
+ words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD;
+ if (words_to_transfer > rx_fifo_avail)
+ words_to_transfer = rx_fifo_avail;
+
+ i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer);
+
+ buf += words_to_transfer * BYTES_PER_FIFO_WORD;
+ buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
+ rx_fifo_avail -= words_to_transfer;
+
+ /*
+ * If there is a partial word at the end of buf, handle it manually to
+ * prevent overwriting past the end of buf
+ */
+ if (rx_fifo_avail > 0 && buf_remaining > 0) {
+ BUG_ON(buf_remaining > 3);
+ val = i2c_readl(i2c_dev, I2C_RX_FIFO);
+ memcpy(buf, &val, buf_remaining);
+ buf_remaining = 0;
+ rx_fifo_avail--;
+ }
+
+ BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
+ i2c_dev->msg_buf_remaining = buf_remaining;
+ i2c_dev->msg_buf = buf;
+ return 0;
+}
+
+static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
+{
+ u32 val;
+ int tx_fifo_avail;
+ u8 *buf = i2c_dev->msg_buf;
+ size_t buf_remaining = i2c_dev->msg_buf_remaining;
+ int words_to_transfer;
+
+ val = i2c_readl(i2c_dev, I2C_FIFO_STATUS);
+ tx_fifo_avail = (val & I2C_FIFO_STATUS_TX_MASK) >>
+ I2C_FIFO_STATUS_TX_SHIFT;
+
+ /* Rounds down to not include partial word at the end of buf */
+ words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD;
+ if (words_to_transfer > tx_fifo_avail)
+ words_to_transfer = tx_fifo_avail;
+
+ i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer);
+
+ buf += words_to_transfer * BYTES_PER_FIFO_WORD;
+ buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
+ tx_fifo_avail -= words_to_transfer;
+
+ /*
+ * If there is a partial word at the end of buf, handle it manually to
+ * prevent reading past the end of buf, which could cross a page
+ * boundary and fault.
+ */
+ if (tx_fifo_avail > 0 && buf_remaining > 0) {
+ BUG_ON(buf_remaining > 3);
+ memcpy(&val, buf, buf_remaining);
+ i2c_writel(i2c_dev, val, I2C_TX_FIFO);
+ buf_remaining = 0;
+ tx_fifo_avail--;
+ }
+
+ BUG_ON(tx_fifo_avail > 0 && buf_remaining > 0);
+ i2c_dev->msg_buf_remaining = buf_remaining;
+ i2c_dev->msg_buf = buf;
+ return 0;
+}
+
+/*
+ * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller)
+ * block. This block is identical to the rest of the I2C blocks, except that
+ * it only supports master mode, it has registers moved around, and it needs
+ * some extra init to get it into I2C mode. The register moves are handled
+ * by i2c_readl and i2c_writel
+ */
+static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev)
+{
+ u32 val = 0;
+ val = dvc_readl(i2c_dev, DVC_CTRL_REG3);
+ val |= DVC_CTRL_REG3_SW_PROG;
+ val |= DVC_CTRL_REG3_I2C_DONE_INTR_EN;
+ dvc_writel(i2c_dev, val, DVC_CTRL_REG3);
+
+ val = dvc_readl(i2c_dev, DVC_CTRL_REG1);
+ val |= DVC_CTRL_REG1_INTR_EN;
+ dvc_writel(i2c_dev, val, DVC_CTRL_REG1);
+}
+
+static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
+{
+ u32 val;
+ int err = 0;
+
+ clk_enable(i2c_dev->clk);
+
+ tegra_periph_reset_assert(i2c_dev->clk);
+ udelay(2);
+ tegra_periph_reset_deassert(i2c_dev->clk);
+
+ if (i2c_dev->is_dvc)
+ tegra_dvc_init(i2c_dev);
+
+ val = I2C_CNFG_NEW_MASTER_FSM | I2C_CNFG_PACKET_MODE_EN;
+ i2c_writel(i2c_dev, val, I2C_CNFG);
+ i2c_writel(i2c_dev, 0, I2C_INT_MASK);
+ clk_set_rate(i2c_dev->clk, i2c_dev->bus_clk_rate * 8);
+
+ val = 7 << I2C_FIFO_CONTROL_TX_TRIG_SHIFT |
+ 0 << I2C_FIFO_CONTROL_RX_TRIG_SHIFT;
+ i2c_writel(i2c_dev, val, I2C_FIFO_CONTROL);
+
+ if (tegra_i2c_flush_fifos(i2c_dev))
+ err = -ETIMEDOUT;
+
+ clk_disable(i2c_dev->clk);
+ return err;
+}
+
+static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
+{
+ u32 status;
+ const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
+ struct tegra_i2c_dev *i2c_dev = dev_id;
+
+ status = i2c_readl(i2c_dev, I2C_INT_STATUS);
+
+ if (status == 0) {
+ dev_warn(i2c_dev->dev, "interrupt with no status\n");
+ return IRQ_NONE;
+ }
+
+ if (unlikely(status & status_err)) {
+ if (status & I2C_INT_NO_ACK)
+ i2c_dev->msg_err |= I2C_ERR_NO_ACK;
+ if (status & I2C_INT_ARBITRATION_LOST)
+ i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST;
+ complete(&i2c_dev->msg_complete);
+ goto err;
+ }
+
+ if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
+ if (i2c_dev->msg_buf_remaining)
+ tegra_i2c_empty_rx_fifo(i2c_dev);
+ else
+ BUG();
+ }
+
+ if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
+ if (i2c_dev->msg_buf_remaining)
+ tegra_i2c_fill_tx_fifo(i2c_dev);
+ else
+ tegra_i2c_mask_irq(i2c_dev, I2C_INT_TX_FIFO_DATA_REQ);
+ }
+
+ if ((status & I2C_INT_PACKET_XFER_COMPLETE) &&
+ !i2c_dev->msg_buf_remaining)
+ complete(&i2c_dev->msg_complete);
+
+ i2c_writel(i2c_dev, status, I2C_INT_STATUS);
+ if (i2c_dev->is_dvc)
+ dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
+ return IRQ_HANDLED;
+err:
+ /* An error occured, mask all interrupts */
+ tegra_i2c_mask_irq(i2c_dev, I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST |
+ I2C_INT_PACKET_XFER_COMPLETE | I2C_INT_TX_FIFO_DATA_REQ |
+ I2C_INT_RX_FIFO_DATA_REQ);
+ i2c_writel(i2c_dev, status, I2C_INT_STATUS);
+ return IRQ_HANDLED;
+}
+
+static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
+ struct i2c_msg *msg, int stop)
+{
+ u32 packet_header;
+ u32 int_mask;
+ int ret;
+
+ tegra_i2c_flush_fifos(i2c_dev);
+ i2c_writel(i2c_dev, 0xFF, I2C_INT_STATUS);
+
+ if (msg->len == 0)
+ return -EINVAL;
+
+ i2c_dev->msg_buf = msg->buf;
+ i2c_dev->msg_buf_remaining = msg->len;
+ i2c_dev->msg_err = I2C_ERR_NONE;
+ i2c_dev->msg_read = (msg->flags & I2C_M_RD);
+ INIT_COMPLETION(i2c_dev->msg_complete);
+
+ packet_header = (0 << PACKET_HEADER0_HEADER_SIZE_SHIFT) |
+ PACKET_HEADER0_PROTOCOL_I2C |
+ (i2c_dev->cont_id << PACKET_HEADER0_CONT_ID_SHIFT) |
+ (1 << PACKET_HEADER0_PACKET_ID_SHIFT);
+ i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
+
+ packet_header = msg->len - 1;
+ i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
+
+ packet_header = msg->addr << I2C_HEADER_SLAVE_ADDR_SHIFT;
+ packet_header |= I2C_HEADER_IE_ENABLE;
+ if (msg->flags & I2C_M_TEN)
+ packet_header |= I2C_HEADER_10BIT_ADDR;
+ if (msg->flags & I2C_M_IGNORE_NAK)
+ packet_header |= I2C_HEADER_CONT_ON_NAK;
+ if (msg->flags & I2C_M_NOSTART)
+ packet_header |= I2C_HEADER_REPEAT_START;
+ if (msg->flags & I2C_M_RD)
+ packet_header |= I2C_HEADER_READ;
+ i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
+
+ if (!(msg->flags & I2C_M_RD))
+ tegra_i2c_fill_tx_fifo(i2c_dev);
+
+ int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
+ if (msg->flags & I2C_M_RD)
+ int_mask |= I2C_INT_RX_FIFO_DATA_REQ;
+ else if (i2c_dev->msg_buf_remaining)
+ int_mask |= I2C_INT_TX_FIFO_DATA_REQ;
+ tegra_i2c_unmask_irq(i2c_dev, int_mask);
+ dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n",
+ i2c_readl(i2c_dev, I2C_INT_MASK));
+
+ ret = wait_for_completion_timeout(&i2c_dev->msg_complete, TEGRA_I2C_TIMEOUT);
+ tegra_i2c_mask_irq(i2c_dev, int_mask);
+
+ if (WARN_ON(ret == 0)) {
+ dev_err(i2c_dev->dev, "i2c transfer timed out\n");
+
+ tegra_i2c_init(i2c_dev);
+ return -ETIMEDOUT;
+ }
+
+ dev_dbg(i2c_dev->dev, "transfer complete: %d %d %d\n",
+ ret, completion_done(&i2c_dev->msg_complete), i2c_dev->msg_err);
+
+ if (likely(i2c_dev->msg_err == I2C_ERR_NONE))
+ return 0;
+
+ tegra_i2c_init(i2c_dev);
+ if (i2c_dev->msg_err == I2C_ERR_NO_ACK) {
+ if (msg->flags & I2C_M_IGNORE_NAK)
+ return 0;
+ return -EREMOTEIO;
+ }
+
+ return -EIO;
+}
+
+static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
+ int num)
+{
+ struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
+ int i;
+ int ret = 0;
+
+ if (i2c_dev->is_suspended)
+ return -EBUSY;
+
+ clk_enable(i2c_dev->clk);
+ for (i = 0; i < num; i++) {
+ int stop = (i == (num - 1)) ? 1 : 0;
+ ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], stop);
+ if (ret)
+ break;
+ }
+ clk_disable(i2c_dev->clk);
+ return ret ?: i;
+}
+
+static u32 tegra_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm tegra_i2c_algo = {
+ .master_xfer = tegra_i2c_xfer,
+ .functionality = tegra_i2c_func,
+};
+
+static int tegra_i2c_probe(struct platform_device *pdev)
+{
+ struct tegra_i2c_dev *i2c_dev;
+ struct tegra_i2c_platform_data *pdata = pdev->dev.platform_data;
+ struct resource *res;
+ struct resource *iomem;
+ struct clk *clk;
+ struct clk *i2c_clk;
+ void *base;
+ int irq;
+ int ret = 0;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "no mem resource\n");
+ return -EINVAL;
+ }
+ iomem = request_mem_region(res->start, resource_size(res), pdev->name);
+ if (!iomem) {
+ dev_err(&pdev->dev, "I2C region already claimed\n");
+ return -EBUSY;
+ }
+
+ base = ioremap(iomem->start, resource_size(iomem));
+ if (!base) {
+ dev_err(&pdev->dev, "Cannot ioremap I2C region\n");
+ return -ENOMEM;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "no irq resource\n");
+ ret = -EINVAL;
+ goto err_iounmap;
+ }
+ irq = res->start;
+
+ clk = clk_get(&pdev->dev, NULL);
+ if (IS_ERR(clk)) {
+ dev_err(&pdev->dev, "missing controller clock");
+ ret = PTR_ERR(clk);
+ goto err_release_region;
+ }
+
+ i2c_clk = clk_get(&pdev->dev, "i2c");
+ if (IS_ERR(i2c_clk)) {
+ dev_err(&pdev->dev, "missing bus clock");
+ ret = PTR_ERR(i2c_clk);
+ goto err_clk_put;
+ }
+
+ i2c_dev = kzalloc(sizeof(struct tegra_i2c_dev), GFP_KERNEL);
+ if (!i2c_dev) {
+ ret = -ENOMEM;
+ goto err_i2c_clk_put;
+ }
+
+ i2c_dev->base = base;
+ i2c_dev->clk = clk;
+ i2c_dev->i2c_clk = i2c_clk;
+ i2c_dev->iomem = iomem;
+ i2c_dev->adapter.algo = &tegra_i2c_algo;
+ i2c_dev->irq = irq;
+ i2c_dev->cont_id = pdev->id;
+ i2c_dev->dev = &pdev->dev;
+ i2c_dev->bus_clk_rate = pdata ? pdata->bus_clk_rate : 100000;
+
+ if (pdev->id == 3)
+ i2c_dev->is_dvc = 1;
+ init_completion(&i2c_dev->msg_complete);
+
+ platform_set_drvdata(pdev, i2c_dev);
+
+ ret = tegra_i2c_init(i2c_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to initialize i2c controller");
+ goto err_free;
+ }
+
+ ret = request_irq(i2c_dev->irq, tegra_i2c_isr, 0, pdev->name, i2c_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq);
+ goto err_free;
+ }
+
+ clk_enable(i2c_dev->i2c_clk);
+
+ i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
+ i2c_dev->adapter.owner = THIS_MODULE;
+ i2c_dev->adapter.class = I2C_CLASS_HWMON;
+ strlcpy(i2c_dev->adapter.name, "Tegra I2C adapter",
+ sizeof(i2c_dev->adapter.name));
+ i2c_dev->adapter.algo = &tegra_i2c_algo;
+ i2c_dev->adapter.dev.parent = &pdev->dev;
+ i2c_dev->adapter.nr = pdev->id;
+
+ ret = i2c_add_numbered_adapter(&i2c_dev->adapter);
+ if (ret) {
+ dev_err(&pdev->dev, "Failed to add I2C adapter\n");
+ goto err_free_irq;
+ }
+
+ return 0;
+err_free_irq:
+ free_irq(i2c_dev->irq, i2c_dev);
+err_free:
+ kfree(i2c_dev);
+err_i2c_clk_put:
+ clk_put(i2c_clk);
+err_clk_put:
+ clk_put(clk);
+err_release_region:
+ release_mem_region(iomem->start, resource_size(iomem));
+err_iounmap:
+ iounmap(base);
+ return ret;
+}
+
+static int tegra_i2c_remove(struct platform_device *pdev)
+{
+ struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+ i2c_del_adapter(&i2c_dev->adapter);
+ free_irq(i2c_dev->irq, i2c_dev);
+ clk_put(i2c_dev->i2c_clk);
+ clk_put(i2c_dev->clk);
+ release_mem_region(i2c_dev->iomem->start,
+ resource_size(i2c_dev->iomem));
+ iounmap(i2c_dev->base);
+ kfree(i2c_dev);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int tegra_i2c_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+ i2c_lock_adapter(&i2c_dev->adapter);
+ i2c_dev->is_suspended = true;
+ i2c_unlock_adapter(&i2c_dev->adapter);
+
+ return 0;
+}
+
+static int tegra_i2c_resume(struct platform_device *pdev)
+{
+ struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+ int ret;
+
+ i2c_lock_adapter(&i2c_dev->adapter);
+
+ ret = tegra_i2c_init(i2c_dev);
+
+ if (ret) {
+ i2c_unlock_adapter(&i2c_dev->adapter);
+ return ret;
+ }
+
+ i2c_dev->is_suspended = false;
+
+ i2c_unlock_adapter(&i2c_dev->adapter);
+
+ return 0;
+}
+#endif
+
+static struct platform_driver tegra_i2c_driver = {
+ .probe = tegra_i2c_probe,
+ .remove = tegra_i2c_remove,
+#ifdef CONFIG_PM
+ .suspend = tegra_i2c_suspend,
+ .resume = tegra_i2c_resume,
+#endif
+ .driver = {
+ .name = "tegra-i2c",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init tegra_i2c_init_driver(void)
+{
+ return platform_driver_register(&tegra_i2c_driver);
+}
+
+static void __exit tegra_i2c_exit_driver(void)
+{
+ platform_driver_unregister(&tegra_i2c_driver);
+}
+
+subsys_initcall(tegra_i2c_init_driver);
+module_exit(tegra_i2c_exit_driver);
+
+MODULE_DESCRIPTION("nVidia Tegra2 I2C Bus Controller driver");
+MODULE_AUTHOR("Colin Cross");
+MODULE_LICENSE("GPL v2");