From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Shevchenko Subject: Re: [PATCH] serial: 8250: Fix THRE flag usage for CAP_MINI Date: Wed, 28 Jun 2017 10:48:32 +0300 Message-ID: <1498636112.22624.212.camel@linux.intel.com> References: <1498485581-72097-1-git-send-email-phil@raspberrypi.org> <627a530c-d78c-5338-5ddf-0b3f6a09c37e@i2se.com> <1498554936.22624.180.camel@linux.intel.com> <2669bcda-e1f5-ecb1-a986-99947658bac7@raspberrypi.org> <1498585950.22624.210.camel@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-rpi-kernel" Errors-To: linux-rpi-kernel-bounces+glkr-linux-rpi-kernel=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: Phil Elwell , Stefan Wahren , Greg Kroah-Hartman , Peter Hurley , Yegor Yefremov , Jan Kiszka , linux-serial-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rpi-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-serial@vger.kernel.org On Tue, 2017-06-27 at 22:00 +0100, Phil Elwell wrote: > On 27/06/2017 18:52, Andy Shevchenko wrote: > > On Tue, 2017-06-27 at 11:30 +0100, Phil Elwell wrote: > > > On 27/06/2017 10:15, Andy Shevchenko wrote: > > > > On Mon, 2017-06-26 at 16:15 +0100, Phil Elwell wrote: > > > > > Besides, the "HFIFO" capability looks a lot like quirk to me. > > > > > > > > To me either, which raises a question "Should it be fixed > > > > accordingly?" > > > > > > If I was going to make these quirks, are we simply talking about > > > renaming the > > > capability or is there another mechanism? I've found the 8250_pci > > > quirks, and > > > they look quite different. > > > > Okay, we have several types of flags in the code > > 1. Capabilities: UART_CAP: looks like it defines features of > > hardware > > solely for 8250 compatible devices. > > 2. Flags as quirks UPF_ (I have a patch > > to > > convert them to quirks, need by the way to update and resend): they > > are > > for any serial devices. > > 3. Flags as capabilities: UPF_, similar function as > > UART_CAP, > > but for any serial device. > > > > > > > > I'm also happy to make this code conditional on > > > CONFIG_SERIAL_8250_BCM2835AUX > > > if that is more acceptable. > > > > No, it is undesired. > > > > Can you describe which one from the above suits the best for your > > case? > > This bug I am trying to work around is found in the 8250 > implementation of > one family of CPUs, so I would say capabilities are the best fit > because > they are specific to 8250 drivers. Yeah, looks like UART_CAP suits the best for now. One more comment that UART_CAP_* gather capabilities and quirks at the same time. -- Andy Shevchenko Intel Finland Oy