On Thu, Oct 20, 2011 at 05:39:32PM +0530, Rajendra Nayak wrote: > On Thursday 20 October 2011 11:44 AM, Shawn Guo wrote: > >On Thu, Oct 20, 2011 at 10:48:58AM +0530, Rajendra Nayak wrote: > >>>Let's look at mc13892-regulator driver. There are 23 regulators defined > >>>in array mc13892_regulators. Needless to say, there is a dev behind > >>>mc13892-regulator driver. And when getting probed, this driver will > >>>call regulator_register() to register those 23 regulators individually. > >>>That said, for non-dt world, we have 1 + 23 'dev' with that 1 as the > >>>parent of all other 23 'dev' (wrapped by regulator_dev). But with the > >>>current DT implementation, we will have at least 1 + 23 * 2 'dev'. > >>>These extra 23 'dev' is totally new with DT. > >>> > >> > >>but thats only because the mc13892-regulator driver is implemeted in > >>such a way that all the regulators on the platform are bundled in as > >>*one* device. > > > >I did not look into too many regulator drivers, but I expect this is > >way that most regulator drivers are implemented in. Having > >mc13892-regulator being probed 23 times to register these 23 regulators > >just makes less sense to me. > > > >>It would again depend on how you would pass these from > >>the DT, if you indeed stick to the same way of bundling all regulators > >>as one device from DT, the mc13892-regulator probe would just get called > >>once and there would be one device associated, no? > >> > >Yes, I indeed would stick to the same way of bundling the registration > >of all regulators with mc13892-regulator being probed once. The problem > >I have with the current regulator core DT implementation is that it > >assumes the device_node of rdev->dev (dev wrapped in regulator_dev) is > >being attached to rdev->dev.parent rather than itself. Back to > >mc13892-regulator example, that said, it requires the dev of > >mc13892-regulator have the device_node of individual regulator attached > >to. IOW, the current implementation forces mc13892-regulator to be > >probed 23 times to register those 23 regulators. This is wrong to me. > > I think I now understand to some extent the problem that you seem to be > reporting. It is mainly with drivers which bundle all regulators and > pass them as one device and would want to do so with DT too. > > however I am still not clear on how what you seem to suggest would > solve this problem. Note that not all drivers do it this way, and > there are drivers where each regulator is considered as one device > and I suspect they would remain that way with DT too. And hence we > need to support both. > > Do you have any RFC patch/code which could explain better what you are > suggesting we do here? > > Here is what I changed based on your patches. It only changes drivers/regulator/core.c. ---8<------- diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 9a5ebbe..8fe132d 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1211,7 +1211,7 @@ static struct regulator *_regulator_get(struct device *dev, const char *id, node = of_get_regulator(dev, id); if (node) list_for_each_entry(rdev, ®ulator_list, list) - if (node == rdev->dev.parent->of_node) + if (node == rdev->dev.of_node) goto found; } list_for_each_entry(map, ®ulator_map_list, list) { @@ -2642,9 +2642,6 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, regulator_desc->type != REGULATOR_CURRENT) return ERR_PTR(-EINVAL); - if (!init_data) - return ERR_PTR(-EINVAL); - /* Only one of each should be implemented */ WARN_ON(regulator_desc->ops->get_voltage && regulator_desc->ops->get_voltage_sel); @@ -2675,12 +2672,8 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, INIT_LIST_HEAD(&rdev->list); BLOCKING_INIT_NOTIFIER_HEAD(&rdev->notifier); - /* preform any regulator specific init */ - if (init_data->regulator_init) { - ret = init_data->regulator_init(rdev->reg_data); - if (ret < 0) - goto clean; - } + /* find device_node and attach it */ + rdev->dev.of_node = of_find_node_by_name(NULL, regulator_desc->name); /* register with sysfs */ rdev->dev.class = ®ulator_class; @@ -2693,6 +2686,20 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, goto clean; } + if (!init_data) { + /* try to get init_data from device tree */ + init_data = of_get_regulator_init_data(&rdev->dev); + if (!init_data) + return ERR_PTR(-EINVAL); + } + + /* preform any regulator specific init */ + if (init_data->regulator_init) { + ret = init_data->regulator_init(rdev->reg_data); + if (ret < 0) + goto clean; + } + dev_set_drvdata(&rdev->dev, rdev); /* set regulator constraints */ @@ -2719,7 +2726,7 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, node = of_get_regulator(dev, supply); if (node) list_for_each_entry(r, ®ulator_list, list) - if (node == r->dev.parent->of_node) + if (node == r->dev.of_node) goto found; } ------->8--- And my dts file looks like something below. ecspi@70010000 { /* ECSPI1 */ fsl,spi-num-chipselects = <2>; cs-gpios = <&gpio3 24 0>, /* GPIO4_24 */ <&gpio3 25 0>; /* GPIO4_25 */ status = "okay"; pmic: mc13892@0 { #address-cells = <1>; #size-cells = <0>; compatible = "fsl,mc13892"; spi-max-frequency = <6000000>; reg = <0>; mc13xxx-irq-gpios = <&gpio0 8 0>; /* GPIO1_8 */ regulators { sw1reg: mc13892_sw1 { regulator-min-uV = <600000>; regulator-max-uV = <1375000>; regulator-change-voltage; regulator-boot-on; regulator-always-on; }; sw2reg: mc13892_sw2 { regulator-min-uV = <900000>; regulator-max-uV = <1850000>; regulator-change-voltage; regulator-boot-on; regulator-always-on; }; ...... }; leds { ...... }; buttons { ...... }; }; flash: at45db321d@1 { ...... }; }; }; -- Regards, Shawn -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html