[U-Boot] [PATCH v2 1/4] kirkwood: add kirkwood_mpp_read function

[Valentin Longchamp <valentin.longchamp@keymile.com>]

Hi Prafulla,

On 05/31/2012 10:30 AM, Prafulla Wadaskar wrote:
>> -----Original Message-----
>> From: Valentin Longchamp [mailto:valentin.longchamp at keymile.com]
>> Sent: 30 May 2012 21:12
>> To: Prafulla Wadaskar
>> Cc: Valentin Longchamp; holger.brunck at keymile.com; u-
>> boot at lists.denx.de; Prafulla Wadaskar
>> Subject: [PATCH v2 1/4] kirkwood: add kirkwood_mpp_read function
>>
>> This function can be used to save current mpp state of all mpp pins
>> given in the mpp_list argument by reading the mpp registers, in the
>> second mpp_saved argument.
>>
>> A later call to kirkwood_mpp_conf function with this saved list will
>> reset the mpp configuration as it was when kirkwood_mpp_read was
>> called.
>>
>> Signed-off-by: Valentin Longchamp <valentin.longchamp@keymile.com>
>> cc: Holger Brunck <holger.brunck@keymile.com>
>> cc: Prafulla Wadaskar <prafulla@marvell.com>
>> ---
>>  arch/arm/cpu/arm926ejs/kirkwood/mpp.c    |   41
>> ++++++++++++++++++++++++++++++
>>  arch/arm/include/asm/arch-kirkwood/mpp.h |    1 +
>>  2 files changed, 42 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
>> b/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
>> index 3da6c98..9fb9aea 100644
>> --- a/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
>> +++ b/arch/arm/cpu/arm926ejs/kirkwood/mpp.c
>> @@ -80,3 +80,44 @@ void kirkwood_mpp_conf(u32 *mpp_list)
>>  	debug("\n");
>>
>>  }
>> +
>> +void kirkwood_mpp_read(u32 *mpp_list, u32 *mpp_saved)
>> +{
>> +	u32 mpp_ctrl[MPP_NR_REGS];
>> +	unsigned int variant_mask;
>> +	int i;
>> +
>> +	variant_mask = kirkwood_variant();
>> +	if (!variant_mask)
>> +		return;
>> +
>> +	for (i = 0; i < MPP_NR_REGS; i++) {
>> +		mpp_ctrl[i] = readl(MPP_CTRL(i));
>> +		debug(" %08x", mpp_ctrl[i]);
>> +	}
>> +
>> +	while (*mpp_list) {
>> +		unsigned int num = MPP_NUM(*mpp_list);
>> +		unsigned int sel;
>> +		int shift;
>> +
>> +		if (num > MPP_MAX) {
>> +			debug("kirkwood_mpp_conf: invalid MPP "
>> +					"number (%u)\n", num);
>> +			continue;
>> +		}
>> +		if (!(*mpp_list & variant_mask)) {
>> +			debug("kirkwood_mpp_conf: requested MPP%u config "
>> +				"unavailable on this hardware\n", num);
>> +			continue;
>> +		}
>> +
>> +		shift = (num & 7) << 2;
>> +		sel = (mpp_ctrl[num / 8] >> shift) & 0xf;
>> +		*mpp_saved = num | (sel << 8) | variant_mask;
>> +
>> +		mpp_list++;
>> +		mpp_saved++;
>> +	}
>> +}
>> +
> 
> Hi Valentin
> There is code duplication, similar code it already there in function  kirkwood_mpp_conf(), to make it short you should use kirkwood_mpp_read function within kirkwood_mpp_conf
> 

Not sure I understand what you mean. You want me to implement the
kirkwood_mpp_read functionnality directly into kirkwood_mpp_conf ?

If this is so, it would mean that I would have to change kirkwood_mpp_conf "API"
to add the second argument (mpp_saved) and then I would have to fix all the
calls to this function. Is that what you mean ?

Val