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Subject: Re: [PATCH 1/4] mfd: ti_am335x_tscadc: store physical address
To: Lee Jones <lee.jones@linaro.org>
References: <20160921161134.6951-1-mugunthanvnm@ti.com>
 <20160921161134.6951-2-mugunthanvnm@ti.com> <20160927194045.GK21388@dell>
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From: Mugunthan V N <mugunthanvnm@ti.com>
Message-ID: <f271b805-82c2-a45e-0de9-39edafd34d2e@ti.com>
Date: Fri, 30 Sep 2016 14:13:16 +0530
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On Wednesday 28 September 2016 01:10 AM, Lee Jones wrote:
> On Wed, 21 Sep 2016, Mugunthan V N wrote:
> 
>> store the physical address of the device in its priv to use it
>> for DMA addressing in the client drivers.
>>
>> Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
>> ---
>>  drivers/mfd/ti_am335x_tscadc.c       | 1 +
>>  include/linux/mfd/ti_am335x_tscadc.h | 1 +
>>  2 files changed, 2 insertions(+)
>>
>> diff --git a/drivers/mfd/ti_am335x_tscadc.c b/drivers/mfd/ti_am335x_tscadc.c
>> index c8f027b..0f3fab4 100644
>> --- a/drivers/mfd/ti_am335x_tscadc.c
>> +++ b/drivers/mfd/ti_am335x_tscadc.c
>> @@ -183,6 +183,7 @@ static	int ti_tscadc_probe(struct platform_device *pdev)
>>  		tscadc->irq = err;
>>  
>>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +	tscadc->tscadc_phys_base = res->start;
> 
> This is unusual.  Can't you use a virt_to_phys() variant instead?
> 

I tried using virt_to_phys(), but its not working for me.
Also saw many drivers uses like this to get physical address
("git grep -n " res->start;" drivers/*").

Regards
Mugunthan V N