Hi Rongrong Zou,
On Mon, Jan 11, 2016 at 07:12:10PM +0800, Rongrong Zou wrote:
> I found a mutex lock in dw_i2c_dev for each adapter,
> struct dw_i2c_dev {
> struct device *dev;
> void __iomem *base;
> struct completion cmd_complete;
> struct mutex lock;
> struct clk *clk;
>
> but there is another lock: adapter->bus_lock, this lock is also
> for each adapter, why we need both of them ?
As far as I can see from the code the master_xfer callback is never called
concurrently for the same adaptor. So indeed the internal lock looks
redundant. I can't remember why I put it there.
baruch
--
http://baruch.siach.name/blog/ ~. .~ Tk Open Systems
=}------------------------------------------------ooO--U--Ooo------------{=
- baruch@xxxxxxxxxx - tel: +972.2.679.5364, http://www.tkos.co.il -
--
To unsubscribe from this list: send the line "unsubscribe linux-i2c" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
