1 files changed, 39 insertions, 63 deletions

diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index b4664037eded..97b9c29e9429 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -25,23 +25,6 @@ struct i2c_gpio_private_data {
 	struct i2c_gpio_platform_data pdata;
 };
 
-/* Toggle SDA by changing the direction of the pin */
-static void i2c_gpio_setsda_dir(void *data, int state)
-{
-	struct i2c_gpio_private_data *priv = data;
-
-	/*
-	 * This is a way of saying "do not drive
-	 * me actively high" which means emulating open drain.
-	 * The right way to do this is for gpiolib to
-	 * handle this, by the function below.
-	 */
-	if (state)
-		gpiod_direction_input(priv->sda);
-	else
-		gpiod_direction_output(priv->sda, 0);
-}
-
 /*
  * Toggle SDA by changing the output value of the pin. This is only
  * valid for pins configured as open drain (i.e. setting the value
@@ -54,17 +37,6 @@ static void i2c_gpio_setsda_val(void *data, int state)
 	gpiod_set_value(priv->sda, state);
 }
 
-/* Toggle SCL by changing the direction of the pin. */
-static void i2c_gpio_setscl_dir(void *data, int state)
-{
-	struct i2c_gpio_private_data *priv = data;
-
-	if (state)
-		gpiod_direction_input(priv->scl);
-	else
-		gpiod_direction_output(priv->scl, 0);
-}
-
 /*
  * Toggle SCL by changing the output value of the pin. This is used
  * for pins that are configured as open drain and for output-only
@@ -116,30 +88,13 @@ static int i2c_gpio_probe(struct platform_device *pdev)
 	struct i2c_gpio_platform_data *pdata;
 	struct i2c_algo_bit_data *bit_data;
 	struct i2c_adapter *adap;
+	enum gpiod_flags gflags;
 	int ret;
 
 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
-	/* First get the GPIO pins; if it fails, we'll defer the probe. */
-	priv->sda = devm_gpiod_get_index(&pdev->dev, NULL, 0, GPIOD_OUT_HIGH);
-	if (IS_ERR(priv->sda)) {
-		ret = PTR_ERR(priv->sda);
-		/* FIXME: hack in the old code, is this really necessary? */
-		if (ret == -EINVAL)
-			ret = -EPROBE_DEFER;
-		return ret;
-	}
-	priv->scl = devm_gpiod_get_index(&pdev->dev, NULL, 1, GPIOD_OUT_LOW);
-	if (IS_ERR(priv->scl)) {
-		ret = PTR_ERR(priv->scl);
-		/* FIXME: hack in the old code, is this really necessary? */
-		if (ret == -EINVAL)
-			ret = -EPROBE_DEFER;
-		return ret;
-	}
-
 	adap = &priv->adap;
 	bit_data = &priv->bit_data;
 	pdata = &priv->pdata;
@@ -157,27 +112,48 @@ static int i2c_gpio_probe(struct platform_device *pdev)
 	}
 
 	/*
-	 * FIXME: this is a hack emulating the open drain emulation
-	 * that gpiolib can already do for us. Make all clients properly
-	 * flag their lines as open drain and get rid of this property
-	 * and the special callback.
+	 * First get the GPIO pins; if it fails, we'll defer the probe.
+	 * If the SDA line is marked from platform data or device tree as
+	 * "open drain" it means something outside of our control is making
+	 * this line being handled as open drain, and we should just handle
+	 * it as any other output. Else we enforce open drain as this is
+	 * required for an I2C bus.
 	 */
-	if (pdata->sda_is_open_drain) {
-		gpiod_direction_output(priv->sda, 1);
-		bit_data->setsda = i2c_gpio_setsda_val;
-	} else {
-		gpiod_direction_input(priv->sda);
-		bit_data->setsda = i2c_gpio_setsda_dir;
+	if (pdata->sda_is_open_drain)
+		gflags = GPIOD_OUT_HIGH;
+	else
+		gflags = GPIOD_OUT_HIGH_OPEN_DRAIN;
+	priv->sda = devm_gpiod_get_index(&pdev->dev, NULL, 0, gflags);
+	if (IS_ERR(priv->sda)) {
+		ret = PTR_ERR(priv->sda);
+		/* FIXME: hack in the old code, is this really necessary? */
+		if (ret == -EINVAL)
+			ret = -EPROBE_DEFER;
+		return ret;
 	}
-
-	if (pdata->scl_is_open_drain || pdata->scl_is_output_only) {
-		gpiod_direction_output(priv->scl, 1);
-		bit_data->setscl = i2c_gpio_setscl_val;
-	} else {
-		gpiod_direction_input(priv->scl);
-		bit_data->setscl = i2c_gpio_setscl_dir;
+	/*
+	 * If the SCL line is marked from platform data or device tree as
+	 * "open drain" it means something outside of our control is making
+	 * this line being handled as open drain, and we should just handle
+	 * it as any other output. Else we enforce open drain as this is
+	 * required for an I2C bus.
+	 */
+	if (pdata->scl_is_open_drain)
+		gflags = GPIOD_OUT_LOW;
+	else
+		gflags = GPIOD_OUT_LOW_OPEN_DRAIN;
+	priv->scl = devm_gpiod_get_index(&pdev->dev, NULL, 1, gflags);
+	if (IS_ERR(priv->scl)) {
+		ret = PTR_ERR(priv->scl);
+		/* FIXME: hack in the old code, is this really necessary? */
+		if (ret == -EINVAL)
+			ret = -EPROBE_DEFER;
+		return ret;
 	}
 
+	bit_data->setsda = i2c_gpio_setsda_val;
+	bit_data->setscl = i2c_gpio_setscl_val;
+
 	if (!pdata->scl_is_output_only)
 		bit_data->getscl = i2c_gpio_getscl;
 	bit_data->getsda = i2c_gpio_getsda;