Re: [PATCH V4 4/4] gpio: tegra: Add support for gpio debounce

Laxman Dewangan
2016-04-25T08:52:36Z

On Monday 25 April 2016 11:06 AM, Alexandre Courbot wrote:
> Sorry, just realized I commented on v3...
>
> On Fri, Apr 22, 2016 at 7:09 PM, Laxman Dewangan <ldewangan@nvidia.com> wrote:
>> + spinlock_t dbc_lock[4]; /* Lock for updating debounce count register */
> I'm nit'ing here, but maybe one spinlock shared by all ports would be
> enough? (the same would apply to lvl_lock, so feel free to do this as
> a separate patch) I don't think we expect *that* many concurrent
> accesses, do we?

Really no, but to make the stuff uniform, it should be fine here. If the
registers are not conflicting then do not make under same lock.

>>
>>
>> spin_lock_irqsave(bank->dbc_lock[port], flags);
>> if (bank->dbc_cnt[port] < debounce_ms) {
>> tegra_gpio_writel(tgi, debounce_ms, GPIO_DBC_CNT(tgi, offset));
>> bank->dbc_cnt[port] = debounce_ms;
>> }
>> spin_unlock_irqrestore(&bank->dbc_lock[port], flags);
>>
>> Which is nicer to the eyes.
>>

OK, this also looks fine. As I am goign to respin this for V5 (for gc as
instance rather than pointer), I will take care of it.