Messages in this thread | | | Date | Sun, 27 Jan 2013 14:06:36 +0800 | From | Mark Brown <> | Subject | Re: [PATCH v2 2/4] regulator-core: manage enable GPIO list |
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On Tue, Jan 15, 2013 at 04:35:46AM +0000, Kim, Milo wrote:
> +/** > + * Balance enable_count of each GPIO and actual GPIO pin control. > + * GPIO is enabled in case of initial use. (enable_count is 0) > + * GPIO is disabled when it is not shared any more. (enable_count is 1) > + */ > +static void _do_ena_gpio_ctrl(struct regulator_enable_gpio *pin, > + struct regulator_dev *rdev, bool enable) > +{ > + if (enable) { > + /* Enable GPIO at initial use */ > + if (pin->enable_count == 0) > + gpio_set_value_cansleep(rdev->ena_gpio, > + !rdev->ena_gpio_invert); > + > + rdev->ena_gpio_state = 1;
ena_gpio_state is redundant with this patch, we can just replace references to it with pin->enable_count.
We'll also need a request count to keep track of how many regulators are using the GPIO for use in cleanup.
> + } else { > + rdev->ena_gpio_state = 0; > + if (pin->enable_count > 1) { > + pin->enable_count--; > + return; > + } > + > + /* Disable GPIO if not used */ > + if (pin->enable_count == 1) { > + gpio_set_value_cansleep(rdev->ena_gpio, > + rdev->ena_gpio_invert); > + pin->enable_count = 0; > + }
Ideally we should also check if we're trying to take the enable count below zero and complain about that.
> +static void regulator_ena_gpio_ctrl(struct regulator_dev *rdev, bool enable) > +{ > + struct regulator_enable_gpio *pin; > + > + list_for_each_entry(pin, ®ulator_ena_gpio_list, list) { > + if (pin->gpio == rdev->ena_gpio) { > + _do_ena_gpio_ctrl(pin, rdev, enable); > + return; > + } > + } > +}
This should return an error code as the users return errors, the GPIO API won't give us errors but we can generate them internally. It'd be better to just add a pointer to the GPIO struct to the regulator_dev (in place of the GPIO) so we don't need to scan through the list every time we look for the GPIO. [unhandled content-type:application/pgp-signature] | |