From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH v1 03/63] Input: atmel_mxt_ts - only read messages in mxt_acquire_irq() when necessary Date: Fri, 16 Aug 2019 10:16:22 -0700 Message-ID: <20190816171622.GF121898@dtor-ws> References: <20190816082952.17985-1-jiada_wang@mentor.com> <20190816082952.17985-4-jiada_wang@mentor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190816082952.17985-4-jiada_wang@mentor.com> Sender: linux-kernel-owner@vger.kernel.org To: Jiada Wang Cc: nick@shmanahar.org, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, george_davis@mentor.com List-Id: linux-input@vger.kernel.org On Fri, Aug 16, 2019 at 05:28:52PM +0900, Jiada Wang wrote: > From: Nick Dyer > > The workaround of reading all messages until an invalid is received is a > way of forcing the CHG line high, which means that when using > edge-triggered interrupts the interrupt can be acquired. > > With level-triggered interrupts the workaround is unnecessary. > > Also, most recent maXTouch chips have a feature called RETRIGEN which, when > enabled, reasserts the interrupt line every cycle if there are messages > waiting. This also makes the workaround unnecessary. > > Note: the RETRIGEN feature is only in some firmware versions/chips, it's > not valid simply to enable the bit. Instead of trying to work around of misconfiguration for IRQ/firmware, can we simply error out of probe if we see a level interrupt with !RETRIGEN firmware? Thanks. -- Dmitry