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path: root/drivers/i2c/busses/i2c-tegra.c
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Diffstat (limited to 'drivers/i2c/busses/i2c-tegra.c')
-rw-r--r--drivers/i2c/busses/i2c-tegra.c122
1 files changed, 59 insertions, 63 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 3da7ee3..66eb53f 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -97,8 +97,21 @@
#define I2C_HEADER_10BIT_ADDR (1<<18)
#define I2C_HEADER_IE_ENABLE (1<<17)
#define I2C_HEADER_REPEAT_START (1<<16)
+#define I2C_HEADER_CONTINUE_XFER (1<<15)
#define I2C_HEADER_MASTER_ADDR_SHIFT 12
#define I2C_HEADER_SLAVE_ADDR_SHIFT 1
+/*
+ * msg_end_type: The bus control which need to be send at end of transfer.
+ * @MSG_END_STOP: Send stop pulse at end of transfer.
+ * @MSG_END_REPEAT_START: Send repeat start at end of transfer.
+ * @MSG_END_CONTINUE: The following on message is coming and so do not send
+ * stop or repeat start.
+ */
+enum msg_end_type {
+ MSG_END_STOP,
+ MSG_END_REPEAT_START,
+ MSG_END_CONTINUE,
+};
/**
* struct tegra_i2c_dev - per device i2c context
@@ -106,7 +119,6 @@
* @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
@@ -124,7 +136,6 @@ struct tegra_i2c_dev {
struct i2c_adapter adapter;
struct clk *clk;
struct clk *i2c_clk;
- struct resource *iomem;
void __iomem *base;
int cont_id;
int irq;
@@ -165,6 +176,10 @@ 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));
+
+ /* Read back register to make sure that register writes completed */
+ if (reg != I2C_TX_FIFO)
+ readl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
}
static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned long reg)
@@ -449,7 +464,7 @@ err:
}
static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
- struct i2c_msg *msg, int stop)
+ struct i2c_msg *msg, enum msg_end_type end_state)
{
u32 packet_header;
u32 int_mask;
@@ -476,7 +491,9 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
packet_header = I2C_HEADER_IE_ENABLE;
- if (!stop)
+ if (end_state == MSG_END_CONTINUE)
+ packet_header |= I2C_HEADER_CONTINUE_XFER;
+ else if (end_state == MSG_END_REPEAT_START)
packet_header |= I2C_HEADER_REPEAT_START;
if (msg->flags & I2C_M_TEN) {
packet_header |= msg->addr;
@@ -548,8 +565,14 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
clk_prepare_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);
+ enum msg_end_type end_type = MSG_END_STOP;
+ if (i < (num - 1)) {
+ if (msgs[i + 1].flags & I2C_M_NOSTART)
+ end_type = MSG_END_CONTINUE;
+ else
+ end_type = MSG_END_REPEAT_START;
+ }
+ ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], end_type);
if (ret)
break;
}
@@ -559,7 +582,8 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
static u32 tegra_i2c_func(struct i2c_adapter *adap)
{
- return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR |
+ I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
}
static const struct i2c_algorithm tegra_i2c_algo = {
@@ -572,7 +596,6 @@ static int __devinit 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;
const unsigned int *prop;
@@ -585,50 +608,41 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
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));
+ base = devm_request_and_ioremap(&pdev->dev, res);
if (!base) {
- dev_err(&pdev->dev, "Cannot ioremap I2C region\n");
- return -ENOMEM;
+ dev_err(&pdev->dev, "Cannot request/ioremap I2C registers\n");
+ return -EADDRNOTAVAIL;
}
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!res) {
dev_err(&pdev->dev, "no irq resource\n");
- ret = -EINVAL;
- goto err_iounmap;
+ return -EINVAL;
}
irq = res->start;
- clk = clk_get(&pdev->dev, NULL);
+ clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(clk)) {
dev_err(&pdev->dev, "missing controller clock");
- ret = PTR_ERR(clk);
- goto err_release_region;
+ return PTR_ERR(clk);
}
- i2c_clk = clk_get(&pdev->dev, "i2c");
+ i2c_clk = devm_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;
+ return PTR_ERR(i2c_clk);
}
- i2c_dev = kzalloc(sizeof(struct tegra_i2c_dev), GFP_KERNEL);
+ i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
if (!i2c_dev) {
- ret = -ENOMEM;
- goto err_i2c_clk_put;
+ dev_err(&pdev->dev, "Could not allocate struct tegra_i2c_dev");
+ return -ENOMEM;
}
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;
@@ -657,13 +671,14 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
ret = tegra_i2c_init(i2c_dev);
if (ret) {
dev_err(&pdev->dev, "Failed to initialize i2c controller");
- goto err_free;
+ return ret;
}
- ret = request_irq(i2c_dev->irq, tegra_i2c_isr, 0, pdev->name, i2c_dev);
+ ret = devm_request_irq(&pdev->dev, 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;
+ return ret;
}
clk_prepare_enable(i2c_dev->i2c_clk);
@@ -681,45 +696,26 @@ static int __devinit tegra_i2c_probe(struct platform_device *pdev)
ret = i2c_add_numbered_adapter(&i2c_dev->adapter);
if (ret) {
dev_err(&pdev->dev, "Failed to add I2C adapter\n");
- goto err_free_irq;
+ clk_disable_unprepare(i2c_dev->i2c_clk);
+ return ret;
}
of_i2c_register_devices(&i2c_dev->adapter);
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 __devexit 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)
+static int tegra_i2c_suspend(struct device *dev)
{
- struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+ struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
i2c_lock_adapter(&i2c_dev->adapter);
i2c_dev->is_suspended = true;
@@ -728,9 +724,9 @@ static int tegra_i2c_suspend(struct platform_device *pdev, pm_message_t state)
return 0;
}
-static int tegra_i2c_resume(struct platform_device *pdev)
+static int tegra_i2c_resume(struct device *dev)
{
- struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+ struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
int ret;
i2c_lock_adapter(&i2c_dev->adapter);
@@ -748,6 +744,11 @@ static int tegra_i2c_resume(struct platform_device *pdev)
return 0;
}
+
+static SIMPLE_DEV_PM_OPS(tegra_i2c_pm, tegra_i2c_suspend, tegra_i2c_resume);
+#define TEGRA_I2C_PM (&tegra_i2c_pm)
+#else
+#define TEGRA_I2C_PM NULL
#endif
#if defined(CONFIG_OF)
@@ -758,21 +759,16 @@ static const struct of_device_id tegra_i2c_of_match[] __devinitconst = {
{},
};
MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
-#else
-#define tegra_i2c_of_match NULL
#endif
static struct platform_driver tegra_i2c_driver = {
.probe = tegra_i2c_probe,
.remove = __devexit_p(tegra_i2c_remove),
-#ifdef CONFIG_PM
- .suspend = tegra_i2c_suspend,
- .resume = tegra_i2c_resume,
-#endif
.driver = {
.name = "tegra-i2c",
.owner = THIS_MODULE,
- .of_match_table = tegra_i2c_of_match,
+ .of_match_table = of_match_ptr(tegra_i2c_of_match),
+ .pm = TEGRA_I2C_PM,
},
};
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