From mboxrd@z Thu Jan  1 00:00:00 1970
From: Heiko Schocher <hs@denx.de>
Date: Tue, 24 Feb 2009 08:53:33 +0100
Subject: [U-Boot] [PATCH 4/9 v3] 83xx, i2c: add mux support for fsl_i2c
In-Reply-To: <20090223163548.7bcc21b6.kim.phillips@freescale.com>
References: <499D87A9.3060004@denx.de>
	<20090223163548.7bcc21b6.kim.phillips@freescale.com>
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Hello Kim,

Kim Phillips wrote:
> On Thu, 19 Feb 2009 17:24:09 +0100
> Heiko Schocher <hs@denx.de> wrote:
[...]
>>  unsigned int i2c_get_bus_num(void)
>>  {
>> +#if defined(CONFIG_I2C_MUX)
>> +	return i2c_bus_num_mux;
>> +#else
>>  	return i2c_bus_num;
>> +#endif
>>  }
> 
> I don't get this mux variant - why aren't we reusing i2c_bus_num in the
> mux case?

Because i2c_bus_num is used as an index which hardware i2c controller
is used (0 or 1). In CONFIG_I2C_MUX case, you have more than 2 i2c
busses -> i2c_bus_num would be greater than 1, so you must have a
variable, where you store which hardware adapter you use, and one
which stores on which i2c bus you are.

bye
Heiko
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