From mboxrd@z Thu Jan 1 00:00:00 1970 From: Shawn Lin Subject: Re: [PATCH] pinctrl: rockchip: don't disable clk when irq mask is already set Date: Thu, 29 Sep 2016 15:29:45 +0800 Message-ID: <4414bb4f-d159-504e-5ba2-36807b2421ed@rock-chips.com> References: <1474655197-26919-1-git-send-email-jacob-chen@iotwrt.com> <3592219.tUs91je5kA@phil> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <3592219.tUs91je5kA@phil> Sender: linux-gpio-owner@vger.kernel.org To: Heiko Stuebner Cc: shawn.lin@rock-chips.com, linux-gpio@vger.kernel.org, Jacob Chen , linus.walleij@linaro.org, linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org, Jacob Chen List-Id: linux-rockchip.vger.kernel.org 在 2016/9/27 6:35, Heiko Stuebner 写道: > Am Samstag, 24. September 2016, 18:24:11 CEST schrieb Shawn Lin: >> On 2016/9/24 2:26, Jacob Chen wrote: >>> From: Jacob Chen >>> >>> In some drivers, disable_irq() call don't be symmetric with enable_irq() >>> , disable_irq() will be called before call free_irq(). >> >> Which upstream drivers you refer to? >> >> Shouldn't it be the unbalanced call for these drivers? >> >>> But both disable_irq() and free_irq() will call >>> rockchip_irq_gc_mask_set_bit,> >>> and clk_disable() will be called more times than clk_enable(), which will >>> >>> cause bugs. >>> >>> I think we can correct that by checking of mask.If mask is already set, do >>> nothing. >> Looks like a little hacky to me. > > that may be true, but on first glance I tend to agree with Jacob. > Look for example at (a driver using disable_irq I picked at random) drivertc/ > rtcrs/-tps6586x.c . yep, I took a quick look at the files you pointed to, and it seems there should be the problems for what this patch to deal with. Probably I didn't see this error since the drivers we was using happened to handle it properly but maybe not for other drivers. I am okay if this could solve problems for Jacob. > > In its probe function it does devm_request_irq directly followed by > disable_irq on its alarm interrupt. The interrupt only gets enabled again if > the rtc alarm gets enabled. So you can easily run into the disable + free case > there as well. Similar probably in a lot of other drivers. > > > Heiko > >> >>> Change-Id: If19912c7658253e15531c04db6c70fdbffd5960a >> >> remove this. >> >>> Signed-off-by: Jacob Chen >>> --- >>> >>> drivers/pinctrl/pinctrl-rockchip.c | 4 ++++ >>> 1 file changed, 4 insertions(+) >>> >>> diff --git a/drivers/pinctrl/pinctrl-rockchip.c >>> b/drivers/pinctrl/pinctrl-rockchip.c index c6c04ac..9a8804a 100644 >>> --- a/drivers/pinctrl/pinctrl-rockchip.c >>> +++ b/drivers/pinctrl/pinctrl-rockchip.c >>> @@ -2334,8 +2334,12 @@ static void rockchip_irq_gc_mask_clr_bit(struct >>> irq_data *d)> >>> void rockchip_irq_gc_mask_set_bit(struct irq_data *d) >>> { >>> >>> struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d); >>> >>> + struct irq_chip_type *ct = irq_data_get_chip_type(d); >>> >>> struct rockchip_pin_bank *bank = gc->private; >>> >>> + if (*ct->mask_cache & d->mask) >>> + return; >>> + >>> >>> irq_gc_mask_set_bit(d); >>> clk_disable(bank->clk); >>> >>> } >>> >>> -- >>> 2.7.4 >>> >>> >>> _______________________________________________ >>> Linux-rockchip mailing list >>> Linux-rockchip@lists.infradead.org >>> http://lists.infradead.org/mailman/listinfo/linux-rockchip > > > > _______________________________________________ > Linux-rockchip mailing list > Linux-rockchip@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-rockchip > -- Best Regards Shawn Lin