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linux/drivers/i2c/busses/i2c-tegra.c
Todd Poynor cb63c62d8e i2c: tegra: recover from spurious interrupt storm 
Re-init the I2C controller when an IRQ arrives with no
I2C_INT_STATUS bits set to indicate why the interrupt was sent.
Storms of such mystery interrupts are infrequently seen.

Dump some more status when these interrupts arrive.  Set an error
for the current request and wake up the requester (rather than
timing out the request or possibly silently ignoring the interrupts).

If the I2C block is inside the DVC, also ACK the DVC I2C transfer
done interrupt in the ISR error return path, as is done for the
normal return path.

Signed-off-by: Todd Poynor <toddpoynor@google.com>
[swarren: Fix minor checkpatch whitespace issue, commit tag]
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-05-11 06:45:50 +01:00

728 lines
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/*
* 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_STATUS 0x01C
#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 I2C_ERR_UNKNOWN_INTERRUPT 0x04
#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;
bool irq_disabled;
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);
if (!i2c_dev->is_dvc) {
u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG);
i2c_writel(i2c_dev, sl_cfg | I2C_SL_CNFG_NEWSL, I2C_SL_CNFG);
}
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);
if (i2c_dev->irq_disabled) {
i2c_dev->irq_disabled = 0;
enable_irq(i2c_dev->irq);
}
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, "irq status 0 %08x %08x %08x\n",
i2c_readl(i2c_dev, I2C_PACKET_TRANSFER_STATUS),
i2c_readl(i2c_dev, I2C_STATUS),
i2c_readl(i2c_dev, I2C_CNFG));
i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT;
if (!i2c_dev->irq_disabled) {
disable_irq_nosync(i2c_dev->irq);
i2c_dev->irq_disabled = 1;
}
complete(&i2c_dev->msg_complete);
goto err;
}
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 occurred, 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);
if (i2c_dev->is_dvc)
dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_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");
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