From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: Re: [PATCH 3/6] soc/tegra: pmc: Add support for IO pads power state and voltage Date: Tue, 3 May 2016 13:55:17 +0100 Message-ID: <57289FB5.5040705@nvidia.com> References: <1462191434-28933-1-git-send-email-ldewangan@nvidia.com> <1462191434-28933-4-git-send-email-ldewangan@nvidia.com> <57289AC0.4090604@nvidia.com> <57289A2B.7040501@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <57289A2B.7040501-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Laxman Dewangan , swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org, linus.walleij-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, gnurou-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Cc: linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-gpio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-tegra@vger.kernel.org On 03/05/16 13:31, Laxman Dewangan wrote: > > On Tuesday 03 May 2016 06:04 PM, Jon Hunter wrote: >> On 02/05/16 13:17, Laxman Dewangan wrote: >>> + >>> + return tegra_io_rail_power_on(dpd_bit); >> From a readability standpoint the above seems weird because >> tegra_io_pads_power_enable() takes an ID as the argument, translates it >> to a bit value and passes it to tegra_io_rail_power_on() which also >> takes an ID for the argument. > > Yaah, I did not want to duplicate the implementation and hence it is there. > We will get rid of the older APIs once this is IN and new mechanism there. > > > >>> + >>> + bval = (io_volt_uv == 3300000) ? BIT(pwr_bit) : 0; >>> + >>> + mutex_lock(&pmc->powergates_lock); >>> + tegra_pmc_read_modify_write(PMC_PWR_DET, BIT(pwr_bit), >>> BIT(pwr_bit)); >>> + tegra_pmc_read_modify_write(PMC_PWR_DET_VAL, BIT(pwr_bit), bval); >>> + mutex_unlock(&pmc->powergates_lock); >> There are 4 instances of BIT(pwr_bit). May be we should do this once or >> have tegra_io_pads_to_power_val() return the bit? > > OK, will re-write this part. > > >> >>> +int tegra_io_pads_power_disable(int io_pad_id); >>> +int tegra_io_pads_power_is_enabled(int io_pad_id); >> What I don't like here, is now we have two public APIs to do the same >> job because tegra_io_pads_power_enable/disable() calls >> tegra_io_rail_power_off/on() internally. Furthermore, the two APIs use >> different ID definitions to accomplish the same job. This shouldn't be >> necessary. > > Currently SOR driver is using the tegra_io_rail_power_off/on() APIs. > Once the proper interface available then I will move sor driver to use > new method and then we can full get rid of older APIs and macros. > > Till that, we need to have this. I prefer it is done before this series. In other words, if we need a proper enum for the rail/pad IDs then add one and convert any existing drivers over to use any new APIs first. The other option is to live with the existing API names. Jon