2 files changed, 44 insertions, 9 deletions

diff --git a/drivers/w1/masters/mxc_w1.c b/drivers/w1/masters/mxc_w1.c
index 15c7251b055..1e5d94c5afc 100644
--- a/drivers/w1/masters/mxc_w1.c
+++ b/drivers/w1/masters/mxc_w1.c
@@ -46,7 +46,6 @@
 
 struct mxc_w1_device {
 	void __iomem *regs;
-	unsigned int clkdiv;
 	struct clk *clk;
 	struct w1_bus_master bus_master;
 };
@@ -106,8 +105,10 @@ static u8 mxc_w1_ds2_touch_bit(void *data, u8 bit)
 static int mxc_w1_probe(struct platform_device *pdev)
 {
 	struct mxc_w1_device *mdev;
+	unsigned long clkrate;
 	struct resource *res;
-	int err = 0;
+	unsigned int clkdiv;
+	int err;
 
 	mdev = devm_kzalloc(&pdev->dev, sizeof(struct mxc_w1_device),
 			    GFP_KERNEL);
@@ -118,27 +119,39 @@ static int mxc_w1_probe(struct platform_device *pdev)
 	if (IS_ERR(mdev->clk))
 		return PTR_ERR(mdev->clk);
 
-	mdev->clkdiv = (clk_get_rate(mdev->clk) / 1000000) - 1;
+	clkrate = clk_get_rate(mdev->clk);
+	if (clkrate < 10000000)
+		dev_warn(&pdev->dev,
+			 "Low clock frequency causes improper function\n");
+
+	clkdiv = DIV_ROUND_CLOSEST(clkrate, 1000000);
+	clkrate /= clkdiv;
+	if ((clkrate < 980000) || (clkrate > 1020000))
+		dev_warn(&pdev->dev,
+			 "Incorrect time base frequency %lu Hz\n", clkrate);
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	mdev->regs = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(mdev->regs))
 		return PTR_ERR(mdev->regs);
 
-	clk_prepare_enable(mdev->clk);
-	__raw_writeb(mdev->clkdiv, mdev->regs + MXC_W1_TIME_DIVIDER);
+	err = clk_prepare_enable(mdev->clk);
+	if (err)
+		return err;
+
+	__raw_writeb(clkdiv - 1, mdev->regs + MXC_W1_TIME_DIVIDER);
 
 	mdev->bus_master.data = mdev;
 	mdev->bus_master.reset_bus = mxc_w1_ds2_reset_bus;
 	mdev->bus_master.touch_bit = mxc_w1_ds2_touch_bit;
 
-	err = w1_add_master_device(&mdev->bus_master);
+	platform_set_drvdata(pdev, mdev);
 
+	err = w1_add_master_device(&mdev->bus_master);
 	if (err)
-		return err;
+		clk_disable_unprepare(mdev->clk);
 
-	platform_set_drvdata(pdev, mdev);
-	return 0;
+	return err;
 }
 
 /*
diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c
index e36b18b2817..9709b8b484b 100644
--- a/drivers/w1/masters/w1-gpio.c
+++ b/drivers/w1/masters/w1-gpio.c
@@ -18,10 +18,31 @@
 #include <linux/of_gpio.h>
 #include <linux/err.h>
 #include <linux/of.h>
+#include <linux/delay.h>
 
 #include "../w1.h"
 #include "../w1_int.h"
 
+static u8 w1_gpio_set_pullup(void *data, int delay)
+{
+	struct w1_gpio_platform_data *pdata = data;
+
+	if (delay) {
+		pdata->pullup_duration = delay;
+	} else {
+		if (pdata->pullup_duration) {
+			gpio_direction_output(pdata->pin, 1);
+
+			msleep(pdata->pullup_duration);
+
+			gpio_direction_input(pdata->pin);
+		}
+		pdata->pullup_duration = 0;
+	}
+
+	return 0;
+}
+
 static void w1_gpio_write_bit_dir(void *data, u8 bit)
 {
 	struct w1_gpio_platform_data *pdata = data;
@@ -132,6 +153,7 @@ static int w1_gpio_probe(struct platform_device *pdev)
 	} else {
 		gpio_direction_input(pdata->pin);
 		master->write_bit = w1_gpio_write_bit_dir;
+		master->set_pullup = w1_gpio_set_pullup;
 	}
 
 	err = w1_add_master_device(master);