Hello, I'm trying to objectively summarize the discussions in this thread in the hope this helps finding a way that most people can live with. First a description of the status quo: There are several function pairs *get() and *get_optional() that however are different in various aspects. Their relevant properties are listes in the following table. Ideally each line had only identical entries. | clk_get | gpiod_get | platform_get_irq | regulator_get | return value | | | | | on not-found | ERR_PTR(-ENOENT) | ERR_PTR(-ENOENT) | -ENXIO | dummy[1] | (plain get) | | | | | | | | | | return value | | | | | on not-found | dummy[1] | dummy[1] | -ENXIO | ERR_PTR(-ENOENT) | (get_optional) | | | | | | | | | | emits an error message | | | | | on error (including | no | no | yes[2] | no | not-found) | | | | | | | | | | get_optional emits an error | | | | | message on error (including | no | no | no | no | not-found) | | | | | | | | | | summary: | returning a dummy | returning a dummy | doesn't emit an | returning error code | *_get_optional() differs from | on not-found | on not-found | error message | on not-found | *_get by: | | | | | [1] the dummy value is a valid resource descriptor, the API functions are a noop for this dummy value. This dummy value is NULL for all three subsystems. [2] no error is printed for -EPROBE_DEFER. The inversion between clk+gpio vs. regulator is unforunate, swaping one or the other would be good for consistency, but this isn't the topic of this thread. Only so much: It's not agreed upon which variant is the better one and the difference is of historical origin. There are now different suggestions to improve the situation regarding platform_get_irq() compared to the other functions: a) by Sergey platform_get_irq_optional() is changed to return 0 on not-found. b) by Uwe rename platform_get_irq_optional() to platform_get_irq_silent() The argument pro a) is: platform_get_irq_optional() is aligned to clk_get() and gpiod_get() by returning 0 on not-found. The argument contra a) The return value 0 for platform_get_irq() is only syntactically nearer to the dummy value of clk_get() and gpiod_get(). A dummy value isn't available and probably not sensible to introduce for irq because most drivers have to check for the not-found situation anyhow to setup polling. The argument pro b) is: The relevant difference between platform_get_irq() and its optional variant is that the latter is silent. This is a different concept for the meaning of optional compared to the other *_get_optional(). The argument contra b) is: The chosen name is bad, because driver authors might wonder what a silent irq is. ---- end of summary A possible compromise: We can have both. We rename platform_get_irq_optional() to platform_get_irq_silent() (or platform_get_irq_silently() if this is preferred) and once all users are are changed (which can be done mechanically), we reintroduce a platform_get_irq_optional() with Sergey's suggested semantic (i.e. return 0 on not-found, no error message printking). Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ |
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