>-----Original Message-----
>From: Balbi, Felipe 
>Sent: Thursday, September 23, 2010 12:06 PM
>To: Kalliguddi, Hema
>Cc: [email protected]; [email protected]; 
>Basak, Partha; Balbi, Felipe; Tony Lindgren; Kevin Hilman; 
>Cousson, Benoit; Paul Walmsley
>Subject: Re: [PATCH 8/9 v3] usb : musb: Using runtime pm apis for musb.
>
>Hi,
>
>On Wed, Sep 22, 2010 at 07:30:30PM -0500, Kalliguddi, Hema wrote:
>>Calling runtime pm APIs pm_runtime_put_sync() and 
>pm_runtime_get_sync()
>>for enabling/disabling the clocks,sysconfig settings.
>>
>>Also need to put the USB in force standby and force idle mode 
>when usb not used
>>and set it back to no idle and no stndby after wakeup.
>>For OMAP3 auto idle bit has to be disabled because of the 
>errata.So using
>>HWMOD_NO_OCP_AUTOIDLE flag for OMAP3430.
>>
>>Signed-off-by: Hema HK <[email protected]>
>>Signed-off-by: Basak, Partha <[email protected]>
>>Cc: Felipe Balbi <[email protected]>
>>Cc: Tony Lindgren <[email protected]>
>>Cc: Kevin Hilman <[email protected]>
>>Cc: Cousson, Benoit <[email protected]>
>>Cc: Paul Walmsley <[email protected]>
>
>these two should a separate series, otherwise it's difficult for
>different maintainers to decide what they need to pick up :-)
>
I don't mind 
>Anyways, let me continue;
>
>>@@ -2424,13 +2425,16 @@ static int musb_suspend(struct device *d
>>               * they will even be wakeup-enabled.
>>               */
>>      }
>>+     pm_runtime_put_sync(dev);
>>
>>+#ifndef CONFIG_PM_RUNTIME
>>      musb_save_context(musb);
>>
>>      if (musb->set_clock)
>>              musb->set_clock(musb->clock, 0);
>>      else
>>              clk_disable(musb->clock);
>>+#endif
>
>I would rather remove these, adding ifdefs is bad :-( Unless 
>other archs
>(blackfin, davinci) would have problems if we remove those.
>
If we remove this then how the clock will be enabled for the other platforms 
where runtime
pm is not used?

>>@@ -2457,9 +2465,26 @@ static int musb_resume_noirq(struct devi
>>      return 0;
>> }
>>
>>+static int musb_runtime_suspend(struct device *dev)
>>+{
>>+     struct musb     *musb = dev_to_musb(dev);
>
>missing lock ??
I am wondering whether we need the lock here? As these functions are supposed 
to be
Called by runtime pm framework only. 
>
>>+     musb_save_context(musb);
>
>shouldn't you disable the clock here ?
>
This hook is called when we call pm_runtime_put_sync api which takes care of 
disabling
clocks and configuring the sysconfig register.

>>+     return 0;
>>+}
>>+
>>+static int musb_runtime_resume(struct device *dev)
>>+{
>>+     struct musb     *musb = dev_to_musb(dev);
>
>re-enable clock here and missing lock ??
>

Not required. This hook gets aclled when pm_runtime_get_sync is called by the 
driver
Which will take care of enabling the clock.

I am just wondering whether we need the lock here? As these functions are 
supposed to be
Called by runtime pm framework only. 

>>@@ -253,15 +240,13 @@ int __init musb_platform_init(struct mus
>> void musb_platform_save_context(struct musb *musb,
>>              struct musb_context_registers *musb_context)
>> {
>>-     musb_context->otg_sysconfig = musb_readl(musb->mregs, 
>OTG_SYSCONFIG);
>>-     musb_context->otg_forcestandby = 
>musb_readl(musb->mregs, OTG_FORCESTDBY);
>>+     musb_writel(musb->mregs, OTG_FORCESTDBY, ENABLEFORCE);
>
>not really saving context anymore :-p but that's ok, we will 
>need change
>all that mess anyway.
>
Yehh :-)

>>@@ -277,37 +262,23 @@ static int musb_platform_suspend(struct
>>      l |= ENABLEFORCE;       /* enable MSTANDBY */
>>      musb_writel(musb->mregs, OTG_FORCESTDBY, l);
>>
>>-     l = musb_readl(musb->mregs, OTG_SYSCONFIG);
>>-     l |= ENABLEWAKEUP;      /* enable wakeup */
>>-     musb_writel(musb->mregs, OTG_SYSCONFIG, l);
>>-
>>      otg_set_suspend(musb->xceiv, 1);
>>
>>-     if (musb->set_clock)
>>-             musb->set_clock(musb->clock, 0);
>>-     else
>>-             clk_disable(musb->clock);
>>-
>
>should you pm_runtime_put_sync(dev) here ??
>
Calling pm_runtime_put_sync leading to crash as
driver_detach calls __device_release_driver which intern calls 
pm_runtime_put_sync function, with this the musb clocks are already disabled
And usecount is 0.
 
>>      return 0;
>> }
>>
>> static int musb_platform_resume(struct musb *musb)
>> {
>>      u32 l;
>>+     struct device *dev = musb->controller;
>>
>>      if (!musb->clock)
>>              return 0;
>
>you're not touching clock anymore, this can go too.
>
Yes. This can be removed.

>>      otg_set_suspend(musb->xceiv, 0);
>>
>>-     if (musb->set_clock)
>>-             musb->set_clock(musb->clock, 1);
>>-     else
>>-             clk_enable(musb->clock);
>>-
>>-     l = musb_readl(musb->mregs, OTG_SYSCONFIG);
>>-     l &= ~ENABLEWAKEUP;     /* disable wakeup */
>>-     musb_writel(musb->mregs, OTG_SYSCONFIG, l);
>>+     pm_runtime_enable(dev);
>>+     pm_runtime_get_sync(dev);
>
>seems like you're going to call pm_runtime_get_sync twice ? once here
>and another time on musb_resume_noirq(). why ?

pm_runtime_get_sync is called in the musb_platform_resume function 
during the initialization of the driver. Where we need to enable the clocks
and put the sysconfig registers to known configurations.

pm_runtime_get_sync is called in musb_resume_noirq() to re-enable the cloks
and configure the sysconfig because the clocks are disabled in musb_suspend()
by calling pm_runtime_put_sync() during global suspend/resume.


>
>-- 
>balbi
>--
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