[PATCH v5 1/5] phy: add a driver for the Rockchip SoC internal USB2.0 PHY

Kishon Vijay Abraham I kishon at ti.com
Wed Dec 10 22:27:47 PST 2014


Hi,

On Thursday 11 December 2014 11:42 AM, Joe Perches wrote:
> On Thu, 2014-12-11 at 11:32 +0530, Kishon Vijay Abraham I wrote:
>> On Wednesday 10 December 2014 04:16 PM, Yunzhi Li wrote:
>>> diff --git a/drivers/phy/phy-rockchip-usb.c b/drivers/phy/phy-rockchip-usb.c
> []
>>> +/*
>>> + * The higher 16-bit of this register is used for write protection
>>> + * only if BIT(13 + 16) set to 1 the BIT(13) can be written.
>>> + */
>>> +#define SIDDQ_MSK		BIT(13 + 16)
> 
> huh?
> 
> This #define looks _very_ odd.
> 
> Is this supposed to be a single bit 29 or
> some range?

>From what I understood, the most significant 16 bits are write locks to the
least significant 16 bits.

So If I have to write something on bit 0, I have to set bit 16.
If I have to write something on bit 1, I have to set bit 17.
If I have to write something on bit 2, I have to set bit 18.
and so on.

Thanks
Kishon



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