| Message ID | 1423522272-24472-2-git-send-email-gavidov@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Feb 09, 2015 at 03:51:11PM -0700, Gilad Avidov wrote: > According to spmi spec a slave powers up into startup state and then > transitions into active state. Thus, the wakeup command is not required > before calling the slave's probe. The wakeup command is only needed for > slaves that are in sleep state after receiving the sleep command. > > This is a bug since spmi master controllers, such as spmi-pmic-arb, > which have no support for wakeup command return an error on that > command and thus fail before reaching a slave driver probe. If masters are required by the spec to support all commands as Stephen mentions, then I'd argue this is not a bug in the core code at all, but in the spmi-pmic-arb driver. But, unfortunately, having lost access to the spec, I'll defer. Regardless, I think this is useful as an optimization, just with dubious justification. Therefore, Acked-by: Josh Cartwright <joshc@eso.teric.us> Josh -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 02/18/15 07:39, Josh Cartwright wrote: > On Mon, Feb 09, 2015 at 03:51:11PM -0700, Gilad Avidov wrote: >> According to spmi spec a slave powers up into startup state and then >> transitions into active state. Thus, the wakeup command is not required >> before calling the slave's probe. The wakeup command is only needed for >> slaves that are in sleep state after receiving the sleep command. >> >> This is a bug since spmi master controllers, such as spmi-pmic-arb, >> which have no support for wakeup command return an error on that >> command and thus fail before reaching a slave driver probe. > If masters are required by the spec to support all commands as Stephen > mentions, then I'd argue this is not a bug in the core code at all, but > in the spmi-pmic-arb driver. But, unfortunately, having lost access to > the spec, I'll defer. > > Regardless, I think this is useful as an optimization, just with dubious > justification. > > Therefore, > > Acked-by: Josh Cartwright <joshc@eso.teric.us> > > Agreed, it's mostly an optimization and aligns the code more with the spec. How about we drop the "This is a bug" part? With that done, Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
On Wed, 18 Feb 2015 11:17:13 -0800 Stephen Boyd <sboyd@codeaurora.org> wrote: > On 02/18/15 07:39, Josh Cartwright wrote: > > On Mon, Feb 09, 2015 at 03:51:11PM -0700, Gilad Avidov wrote: > >> According to spmi spec a slave powers up into startup state and > >> then transitions into active state. Thus, the wakeup command is > >> not required before calling the slave's probe. The wakeup command > >> is only needed for slaves that are in sleep state after receiving > >> the sleep command. > >> > >> This is a bug since spmi master controllers, such as spmi-pmic-arb, > >> which have no support for wakeup command return an error on that > >> command and thus fail before reaching a slave driver probe. > > If masters are required by the spec to support all commands as > > Stephen mentions, then I'd argue this is not a bug in the core code > > at all, but in the spmi-pmic-arb driver. But, unfortunately, > > having lost access to the spec, I'll defer. > > > > Regardless, I think this is useful as an optimization, just with > > dubious justification. > > > > Therefore, > > > > Acked-by: Josh Cartwright <joshc@eso.teric.us> > > > > > > Agreed, it's mostly an optimization and aligns the code more with the > spec. How about we drop the "This is a bug" part? > As Stephen suggested, I'll drop the bug part. Thank you for the reviews, Gilad > With that done, > > Reviewed-by: Stephen Boyd <sboyd@codeaurora.org> > -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/spmi/spmi.c b/drivers/spmi/spmi.c index 1d92f51..9493843 100644 --- a/drivers/spmi/spmi.c +++ b/drivers/spmi/spmi.c @@ -1,4 +1,5 @@ -/* Copyright (c) 2012-2013, The Linux Foundation. All rights reserved. +/* + * Copyright (c) 2012-2015, The Linux Foundation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and @@ -316,11 +317,6 @@ static int spmi_drv_probe(struct device *dev) struct spmi_device *sdev = to_spmi_device(dev); int err; - /* Ensure the slave is in ACTIVE state */ - err = spmi_command_wakeup(sdev); - if (err) - goto fail_wakeup; - pm_runtime_get_noresume(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); @@ -335,7 +331,6 @@ fail_probe: pm_runtime_disable(dev); pm_runtime_set_suspended(dev); pm_runtime_put_noidle(dev); -fail_wakeup: return err; }