Merge branch 'i2c-embedded/for-next' of git://git.pengutronix.de/git/wsa/linux
[firefly-linux-kernel-4.4.55.git] / drivers / i2c / busses / i2c-tegra.c
index 3da7ee3eb505e0816d809093958f0259816c3450..66eb53fac2022363c3cf90fa96d0ad6358234acc 100644 (file)
 #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
  * @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,
        },
 };