[PATCH 2/2] i2c: designware: add speed mode device tree setting

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From: Alan Tull <atull@xxxxxxxxxxxxxxxxxxxxx>

Add "speed-mode" Device Tree property to select between
standard and fast i2c mode.  Previously, driver was hardwired
as fast mode.  Default to fast mode if property is not
present.

Signed-off-by: Alan Tull <atull@xxxxxxxxxxxxxxxxxxxxx>
---
 drivers/i2c/busses/i2c-designware-platdrv.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index bc87733..3fdc775 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -122,7 +122,7 @@ static int dw_i2c_probe(struct platform_device *pdev)
 	struct dw_i2c_dev *dev;
 	struct i2c_adapter *adap;
 	struct resource *mem;
-	int irq, r;
+	int irq, r, speed_prop, ret, speed = DW_IC_CON_SPEED_FAST;
 
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
@@ -167,6 +167,11 @@ static int dw_i2c_probe(struct platform_device *pdev)
 		of_property_read_u32(pdev->dev.of_node,
 				     "i2c-scl-falling-time-ns",
 				     &dev->scl_falling_time);
+
+		ret = of_property_read_u32(pdev->dev.of_node,
+					   "speed-mode", &speed_prop);
+		if (!ret && (speed_prop == 0))
+			speed = DW_IC_CON_SPEED_STD;
 	}
 
 	dev->functionality =
@@ -177,7 +182,7 @@ static int dw_i2c_probe(struct platform_device *pdev)
 		I2C_FUNC_SMBUS_WORD_DATA |
 		I2C_FUNC_SMBUS_I2C_BLOCK;
 	dev->master_cfg =  DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
-		DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
+		DW_IC_CON_RESTART_EN | speed;
 
 	/* Try first if we can configure the device from ACPI */
 	r = dw_i2c_acpi_configure(pdev);
-- 
1.7.9.5

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