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From 76de914223ec09274a7857e0d8cd7b739205dc3c Mon Sep 17 00:00:00 2001
From: Gregory CLEMENT <gregory.clement@free-electrons.com>
Date: Fri, 21 Jun 2013 15:32:06 +0200
Subject: [PATCH 035/203] i2c: mv64xxx: Set bus frequency to 100kHz if
 clock-frequency is not provided

This commit adds checking whether clock-frequency property acquisition
has succeeded. If not, the frequency is set to 100kHz by default.

The Device Tree binding documentation is updated accordingly.

Based on the intials patches from Zbigniew Bodek

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Zbigniew Bodek <zbb@semihalf.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
---
 Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt | 6 +++++-
 drivers/i2c/busses/i2c-mv64xxx.c                      | 6 +++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

--- a/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt
+++ b/Documentation/devicetree/bindings/i2c/i2c-mv64xxx.txt
@@ -6,7 +6,11 @@ Required properties :
  - reg             : Offset and length of the register set for the device
  - compatible      : Should be "marvell,mv64xxx-i2c"
  - interrupts      : The interrupt number
- - clock-frequency : Desired I2C bus clock frequency in Hz.
+
+Optional properties :
+
+ - clock-frequency : Desired I2C bus clock frequency in Hz. If not set the
+default frequency is 100kHz
 
 Examples:
 
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -580,7 +580,11 @@ mv64xxx_of_config(struct mv64xxx_i2c_dat
 		goto out;
 	}
 	tclk = clk_get_rate(drv_data->clk);
-	of_property_read_u32(np, "clock-frequency", &bus_freq);
+
+	rc = of_property_read_u32(np, "clock-frequency", &bus_freq);
+	if (rc)
+		bus_freq = 100000; /* 100kHz by default */
+
 	if (!mv64xxx_find_baud_factors(bus_freq, tclk,
 				       &drv_data->freq_n, &drv_data->freq_m)) {
 		rc = -EINVAL;