Messages in this thread | | | Date | Tue, 10 Feb 2015 11:02:42 +0000 | From | Russell King - ARM Linux <> | Subject | Re: [PATCH] clk: return proper ERR_PTR for clk_get when !HAVE_CLK |
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On Mon, Feb 09, 2015 at 03:29:54PM +0100, Wolfram Sang wrote: > ... which has to do with this. Historically, "clock-frequency" in DT > means the i2c bus speed. This driver used the binding wrong to specify > the IP core clock speed instead and also used a fixed I2C bus speed > then. Now, when wanting to support a) flexible I2C bus speeds and b) > clock information from standard DT clock bindings, we also need to > ensure that we support the now deprecated and wrong binding as a > fallback. And even after having learnt something about the clk API now, > I still think the best fix is to replace all instances of 'if > (!IS_ERR(dev->clk))' with (!IS_ERR_OR_NULL()). Because in our case, NULL > is not success. We should skip any clk API interaction then and use the > fallback mechanisms.
I disagree; I also utterly _hate_ IS_ERR_OR_NULL - this macro has been responsible for a /lot/ of error handling bugs, and I wish the macro would die.
The "test-for-zero-clock-rate" method I showed in my previous email will work for you - and will avoid using this hateful macro while still giving the behaviour you desire, and you won't be caring about the detail of the clk API implementation either.
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