[PATCH v3] ARM: OMAP2+: hwmod: Add a new state to handle hwmods left enabled at init
Rajendra Nayak
rnayak at ti.com
Fri Dec 16 06:03:08 EST 2011
Hi Paul,
On Friday 16 December 2011 04:07 PM, Paul Walmsley wrote:
> On Mon, 21 Nov 2011, Rajendra Nayak wrote:
>
>> > An hwmod with a 'HWMOD_INIT_NO_IDLE' flag set, is left in
>> > enabled state by the hwmod framework post the initial setup.
>> > Once a real user of the device (a driver) tries to enable it
>> > at a later point, the hwmod framework throws a WARN() about
>> > the device being already in enabled state.
>> >
>> > Fix this by introducing a new state '_HWMOD_STATE_ENABLED_AT_INIT'
>> > to identify such devices/hwmods. When the device/hwmod
>> > is requested to be enabled (the first time) by its driver/user,
>> > nothing except the mux-enable and a state change to '_HWMOD_STATE_ENABLED'
>> > is needed. The mux data is board specific and is unavailable during
>> > initial enable() of the device, done by the framework as part of
>> > setup().
>> >
>> > A good example of a such a device is an UART used as debug console.
>> > The UART module needs to be kept enabled through the boot, until the
>> > UART driver takes control of it, for debug prints to appear on
>> > the console.
>> >
>> > Acked-by: Kevin Hilman<khilman at ti.com>
>> > Acked-by: Benoit Cousson<b-cousson at ti.com>
>> > Signed-off-by: Rajendra Nayak<rnayak at ti.com>
> I've tweaked this patch a little bit, mostly to avoid adding a new state,
> which increases the complexity of the rest of the code that handles the
> hwmod state machine. The modified patch below just uses an internal flag.
> Please let me know if you have any comments.
Looks good to me.
thanks,
Rajendra
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