From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.hugovil.com (mail.hugovil.com [162.243.120.170]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DCD5819D880; Thu, 2 Oct 2025 15:53:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=162.243.120.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759420419; cv=none; b=AMy3C2WGRSwXW5KAyegC65kRaTzjRI70iHvcxr71zTLHSdIbykgfefuYflY9tOtcVJJXF8Xr0NFEbeiFCQq7qOCqm7HmdFTVgLxQFQ0mavaKazpsI4R9Hvh3Iap6q3if6iisPonQvnLcbnoQQt9fOiqOvKmg0zfWSwWExhd44sM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759420419; c=relaxed/simple; bh=vjLYvJOecYDB9EUrqeUhF/MZYNg6CB+C6RGu0rMKSnk=; h=Date:From:To:Cc:Message-Id:In-Reply-To:References:Mime-Version: Content-Type:Subject; b=GJFVur9UXVe24lIDQYS2Sr1XDQ2AGdBIb2I7J/dxsXuKPDSNmPo8nvTRdstzKvcqrlfAfCa7sknm87G5VfKQcKZEAo0XUh3TCXz4oxKAoJ0nvsSHJViaCRlEbuJWEyK4dTqDyk4hmUYp1JJH2/B7FGVq7jzv4qyWQVAutA8+L7w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=hugovil.com; spf=pass smtp.mailfrom=hugovil.com; dkim=pass (1024-bit key) header.d=hugovil.com header.i=@hugovil.com header.b=ybBQ8P+x; arc=none smtp.client-ip=162.243.120.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=hugovil.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=hugovil.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=hugovil.com header.i=@hugovil.com header.b="ybBQ8P+x" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=hugovil.com ; s=x; h=Subject:Content-Transfer-Encoding:Mime-Version:Message-Id:Cc:To:From :Date:subject:date:message-id:reply-to; bh=/lko4rz8t3SWehKKGl/EDP80xAecOhLMpeuZOcoe7Sk=; b=ybBQ8P+x1CADQ2k11zWWq4Rz69 t2nd17i/RrMoot4xHJ4Fbywgy2k1W5SsOO/P/7WXo6CA6kgb8Gcp8c97gqgUMchA1TaQ1tnv4RnYd LmGoVmXhPjGy2t/xhSSsu9OTSKh4DkLHx9T6v4fDd/uzfZsFVT3f+XW7Q8CQJDWLCfoY=; Received: from modemcable168.174-80-70.mc.videotron.ca ([70.80.174.168]:34770 helo=pettiford) by mail.hugovil.com with esmtpa (Exim 4.92) (envelope-from ) id 1v4Lcb-0001e7-GD; Thu, 02 Oct 2025 11:53:33 -0400 Date: Thu, 2 Oct 2025 11:53:33 -0400 From: Hugo Villeneuve To: Greg KH Cc: jirislaby@kernel.org, fvallee@eukrea.fr, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, Hugo Villeneuve , stable@vger.kernel.org Message-Id: <20251002115333.23f1c4a535a4a6f64cdca8a2@hugovil.com> In-Reply-To: <2025100219-neon-litter-24c0@gregkh> References: <20251002145738.3250272-1-hugo@hugovil.com> <20251002145738.3250272-2-hugo@hugovil.com> <2025100219-neon-litter-24c0@gregkh> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 70.80.174.168 X-SA-Exim-Mail-From: hugo@hugovil.com X-Spam-Level: X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * -2.2 NICE_REPLY_A Looks like a legit reply (A) Subject: Re: [PATCH v2 01/15] serial: sc16is7xx: remove useless enable of enhanced features X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on mail.hugovil.com) Hi Greg, On Thu, 2 Oct 2025 17:43:52 +0200 Greg KH wrote: > On Thu, Oct 02, 2025 at 10:57:24AM -0400, Hugo Villeneuve wrote: > > From: Hugo Villeneuve > > > > Commit 43c51bb573aa ("sc16is7xx: make sure device is in suspend once > > probed") permanently enabled access to the enhanced features in > > sc16is7xx_probe(), and it is never disabled after that. > > > > Therefore, remove useless re-enable of enhanced features in > > sc16is7xx_set_baud(). > > > > Fixes: 43c51bb573aa ("sc16is7xx: make sure device is in suspend once probed") > > Cc: stable@vger.kernel.org > > Signed-off-by: Hugo Villeneuve > > --- > > drivers/tty/serial/sc16is7xx.c | 7 ------- > > 1 file changed, 7 deletions(-) > > > > diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c > > index 1a2c4c14f6aac..c7435595dce13 100644 > > --- a/drivers/tty/serial/sc16is7xx.c > > +++ b/drivers/tty/serial/sc16is7xx.c > > @@ -588,13 +588,6 @@ static int sc16is7xx_set_baud(struct uart_port *port, int baud) > > div /= prescaler; > > } > > > > - /* Enable enhanced features */ > > - sc16is7xx_efr_lock(port); > > - sc16is7xx_port_update(port, SC16IS7XX_EFR_REG, > > - SC16IS7XX_EFR_ENABLE_BIT, > > - SC16IS7XX_EFR_ENABLE_BIT); > > - sc16is7xx_efr_unlock(port); > > - > > /* If bit MCR_CLKSEL is set, the divide by 4 prescaler is activated. */ > > sc16is7xx_port_update(port, SC16IS7XX_MCR_REG, > > SC16IS7XX_MCR_CLKSEL_BIT, > > -- > > 2.39.5 > > > > > > Why is this needed for stable kernels? It's useless, what is it > harming? It is useless, and doing no "harm", but since the device is on a SPI or I2C bus, this is inefficient as it takes precious cycles on these busses. > If so, please send it separately, not as a part of a larger series. That is why this patch is the first in the series, so that it could be easily backported. But I can send it separately, sure. Hugo.