On Thu, Jun 30, 2011 at 5:22 PM, Vasily Khoruzhick <[email protected]> wrote: > On Thursday 30 June 2011 10:49:30 MyungJoo Ham wrote: >> This patch allows the Samsung ADC driver to enable VDD regulator at >> probe and resume and to disable at exit and suspend. >> In a platform where ADC's VDD regulator is not "always-on", this control >> is required although this patch does not provide fine-grained power >> control (turning on the regulator only when being accessed). >> >> However, if VDD regulator ("vdd" for the adc device) is not provided, >> the regulator control will not be activated because there are platforms >> that do not provide regulator for ADC device. >> >> arch_initcall has been modified to module_init in order to allow >> regulators to be available at probe. >> >> Signed-off-by: MyungJoo Ham <[email protected]> >> Signed-off-by: Kyungmin Park <[email protected]> [] >> + adc->vdd = regulator_get(dev, "vdd"); >> + if (IS_ERR(adc->vdd)) { >> + dev_err(dev, "operating without regulator \"vdd\" .\n"); >> + ret = PTR_ERR(adc->vdd); >> + goto err_alloc; >> + } >> + > > NACK. Make it optional, otherwise it breaks s3c24xx. >
Ok. Now, I've got the issue I've worried in the previous patch revision. Anyway, Mark once stated: --- quote starts --- On Sun, Jun 19, 2011 at 12:06 AM, Mark Brown <[email protected]> wrote: >> + if (IS_ERR_OR_NULL(adc->vdd)) { >> + dev_dbg(dev, "operating without regulator %s.\n", >> S3C_ADC_REGULATOR_NAME); >> + adc->vdd = NULL; /* Do not control regulator */ >> + } >> + > > No, don't do this. Just unconditionally assume the regulator is present > if power is essential for use of the device. The regulator API will > stub out correctly if it's not in use to allow things to proceed and if > vdd is genuinely not hooked up then the driver can't function. --- quote ends --- Then, how about unconditionally using ADC VDD for TYPE_ADCV3 (S5PC110/S5PV210/Exynos4210) and forget VDD for older ADC types? Thanks. - MyungJoo -- MyungJoo Ham, Ph.D. Mobile Software Platform Lab, Digital Media and Communications (DMC) Business Samsung Electronics cell: 82-10-6714-2858 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
