6 files changed, 37 insertions, 16 deletions

diff --git a/drivers/i2c/busses/i2c-highlander.c b/drivers/i2c/busses/i2c-highlander.c
index 56dc69e7349f..9ad031ea3300 100644
--- a/drivers/i2c/busses/i2c-highlander.c
+++ b/drivers/i2c/busses/i2c-highlander.c
@@ -382,7 +382,7 @@ static int highlander_i2c_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, dev);
 
 	dev->irq = platform_get_irq(pdev, 0);
-	if (iic_force_poll)
+	if (dev->irq < 0 || iic_force_poll)
 		dev->irq = 0;
 
 	if (dev->irq) {
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 117f367636b8..9696d6ec46c0 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -1007,11 +1007,24 @@ static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap)
 	pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default);
 }
 
-static void i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
+/*
+ * We switch SCL and SDA to their GPIO function and do some bitbanging
+ * for bus recovery. These alternative pinmux settings can be
+ * described in the device tree by a separate pinctrl state "gpio". If
+ * this is missing this is not a big problem, the only implication is
+ * that we can't do bus recovery.
+ */
+static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 		struct platform_device *pdev)
 {
 	struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo;
 
+	i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev);
+	if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) {
+		dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n");
+		return PTR_ERR(i2c_imx->pinctrl);
+	}
+
 	i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl,
 			PINCTRL_STATE_DEFAULT);
 	i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl,
@@ -1021,12 +1034,15 @@ static void i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 	rinfo->scl_gpio = of_get_named_gpio_flags(pdev->dev.of_node,
 			"scl-gpios", 0, NULL);
 
-	if (!gpio_is_valid(rinfo->sda_gpio) ||
-	    !gpio_is_valid(rinfo->scl_gpio) ||
-	    IS_ERR(i2c_imx->pinctrl_pins_default) ||
-	    IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
+	if (rinfo->sda_gpio == -EPROBE_DEFER ||
+	    rinfo->scl_gpio == -EPROBE_DEFER) {
+		return -EPROBE_DEFER;
+	} else if (!gpio_is_valid(rinfo->sda_gpio) ||
+		   !gpio_is_valid(rinfo->scl_gpio) ||
+		   IS_ERR(i2c_imx->pinctrl_pins_default) ||
+		   IS_ERR(i2c_imx->pinctrl_pins_gpio)) {
 		dev_dbg(&pdev->dev, "recovery information incomplete\n");
-		return;
+		return 0;
 	}
 
 	dev_dbg(&pdev->dev, "using scl-gpio %d and sda-gpio %d for recovery\n",
@@ -1036,6 +1052,8 @@ static void i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx,
 	rinfo->unprepare_recovery = i2c_imx_unprepare_recovery;
 	rinfo->recover_bus = i2c_generic_gpio_recovery;
 	i2c_imx->adapter.bus_recovery_info = rinfo;
+
+	return 0;
 }
 
 static u32 i2c_imx_func(struct i2c_adapter *adapter)
@@ -1139,7 +1157,11 @@ static int i2c_imx_probe(struct platform_device *pdev)
 			i2c_imx, IMX_I2C_I2CR);
 	imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR);
 
-	i2c_imx_init_recovery_info(i2c_imx, pdev);
+	/* Init optional bus recovery function */
+	ret = i2c_imx_init_recovery_info(i2c_imx, pdev);
+	/* Give it another chance if pinctrl used is not ready yet */
+	if (ret == -EPROBE_DEFER)
+		goto clk_disable;
 
 	/* Add I2C adapter */
 	ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
diff --git a/drivers/i2c/busses/i2c-iop3xx.c b/drivers/i2c/busses/i2c-iop3xx.c
index 72d6161cf77c..6b9031ccd767 100644
--- a/drivers/i2c/busses/i2c-iop3xx.c
+++ b/drivers/i2c/busses/i2c-iop3xx.c
@@ -459,16 +459,14 @@ iop3xx_i2c_probe(struct platform_device *pdev)
 
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
-		ret = -ENXIO;
+		ret = irq;
 		goto unmap;
 	}
 	ret = request_irq(irq, iop3xx_i2c_irq_handler, 0,
 				pdev->name, adapter_data);
 
-	if (ret) {
-		ret = -EIO;
+	if (ret)
 		goto unmap;
-	}
 
 	memcpy(new_adapter->name, pdev->name, strlen(pdev->name));
 	new_adapter->owner = THIS_MODULE;
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 9b867169142f..42a998fa5f79 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -639,7 +639,7 @@ static int mtk_i2c_probe(struct platform_device *pdev)
 		return PTR_ERR(i2c->pdmabase);
 
 	irq = platform_get_irq(pdev, 0);
-	if (irq <= 0)
+	if (irq < 0)
 		return irq;
 
 	init_completion(&i2c->msg_complete);
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index bea74aa3f56c..44af640496bb 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -1213,7 +1213,7 @@ static int s3c24xx_i2c_probe(struct platform_device *pdev)
 
 	if (!(i2c->quirks & QUIRK_POLL)) {
 		i2c->irq = ret = platform_get_irq(pdev, 0);
-		if (ret <= 0) {
+		if (ret < 0) {
 			dev_err(&pdev->dev, "cannot find IRQ\n");
 			clk_unprepare(i2c->clk);
 			return ret;
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index 7584f292e2fd..d0340b134e72 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -148,7 +148,7 @@ static ssize_t i2cdev_read(struct file *file, char __user *buf, size_t count,
 	if (count > 8192)
 		count = 8192;
 
-	tmp = kmalloc(count, GFP_KERNEL);
+	tmp = kzalloc(count, GFP_KERNEL);
 	if (tmp == NULL)
 		return -ENOMEM;
 
@@ -157,7 +157,8 @@ static ssize_t i2cdev_read(struct file *file, char __user *buf, size_t count,
 
 	ret = i2c_master_recv(client, tmp, count);
 	if (ret >= 0)
-		ret = copy_to_user(buf, tmp, count) ? -EFAULT : ret;
+		if (copy_to_user(buf, tmp, ret))
+			ret = -EFAULT;
 	kfree(tmp);
 	return ret;
 }