From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0438DC433E0 for ; Tue, 2 Jun 2020 19:10:55 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C2157206E2 for ; Tue, 2 Jun 2020 19:10:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="CXGyWmlD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C2157206E2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=baikalelectronics.ru Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=ZsoJ8NpHiTwrmK4L3yrzeHgpVyIp3SP/+lHQhjwAEvU=; b=CXGyWmlD/1GQuY XYIeRerERKCJnMVDd0xBDDeJ0fXbVs0ybDHM4t23yqQK+SoXsi4IBa4wIxHEYxYdbx04dwa1CKHon 9UZzPR9Aat6m41xd/gFhskZF7vBKFhEMmoqeuVsVUMbGTzm3zj7V9hC+sLu6vGctys5fInQk5eYop j1q/cF4EKTTVSH+N/Ha0GQjmAAU0lxccQK1ctBngwRZyDKHOKpmAkHwmhIpLagos2a+CU/5E+Yxf7 bYdm1jLOg18OFYYvANoavSeLA5ntq1dbpWrLCIsJv3cDmf56gbbneaFZKkO0fDT8+R4yOuQtfYpay JUOLcEKKzpa2glZTZsLw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jgCJK-0002Et-5G; Tue, 02 Jun 2020 19:10:54 +0000 Received: from ns2.baikalelectronics.com ([94.125.187.42] helo=mail.baikalelectronics.ru) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jgCJG-0002DB-Ry for linux-arm-kernel@lists.infradead.org; Tue, 02 Jun 2020 19:10:53 +0000 Received: from localhost (unknown [127.0.0.1]) by mail.baikalelectronics.ru (Postfix) with ESMTP id E897C8030835; Tue, 2 Jun 2020 19:10:30 +0000 (UTC) X-Virus-Scanned: amavisd-new at baikalelectronics.ru Received: from mail.baikalelectronics.ru ([127.0.0.1]) by localhost (mail.baikalelectronics.ru [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id IvgS6PU79JwH; Tue, 2 Jun 2020 22:10:27 +0300 (MSK) Date: Tue, 2 Jun 2020 22:10:25 +0300 From: Serge Semin To: Lars Povlsen Subject: Re: [PATCH 01/10] spi: dw: Add support for polled operation via no IRQ specified in DT Message-ID: <20200602191025.ywo77nslrgswh6sw@mobilestation> References: <20200513140031.25633-1-lars.povlsen@microchip.com> <20200513140031.25633-2-lars.povlsen@microchip.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200513140031.25633-2-lars.povlsen@microchip.com> X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200602_121051_258081_CA77779C X-CRM114-Status: GOOD ( 18.47 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Cc: devicetree@vger.kernel.org, Alexandre Belloni , linux-kernel@vger.kernel.org, Serge Semin , linux-spi@vger.kernel.org, SoC Team , Mark Brown , Microchip Linux Driver Support , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, May 13, 2020 at 04:00:22PM +0200, Lars Povlsen wrote: > With this change a SPI controller can be added without having a IRQ > associated, and causing all transfers to be polled. For SPI controllers > without DMA, this can significantly improve performance by less > interrupt handling overhead. > > Reviewed-by: Alexandre Belloni > Signed-off-by: Lars Povlsen > --- > drivers/spi/spi-dw.c | 21 +++++++++++++-------- > 1 file changed, 13 insertions(+), 8 deletions(-) > > diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c > index 31e3f866d11a7..e572eb34a3c1a 100644 > --- a/drivers/spi/spi-dw.c > +++ b/drivers/spi/spi-dw.c > @@ -19,6 +19,8 @@ > #include > #endif > > +#define VALID_IRQ(i) (i >= 0) Mark and Andy are right. It is a good candidate to be in a generic IRQ-related code as Anyd suggested: > > drivers/rtc/rtc-cmos.c:95:#define is_valid_irq(n) ((n) > 0) > > Candidate to be in include/linux/irq.h ? So if you feel like to author additional useful patch integrated into the kernel, this one is a good chance for it. > + > /* Slave spi_dev related */ > struct chip_data { > u8 tmode; /* TR/TO/RO/EEPROM */ > @@ -359,7 +361,7 @@ static int dw_spi_transfer_one(struct spi_controller *master, > spi_enable_chip(dws, 1); > return ret; > } > - } else if (!chip->poll_mode) { > + } else if (!chip->poll_mode && VALID_IRQ(dws->irq)) { > txlevel = min_t(u16, dws->fifo_len / 2, dws->len / dws->n_bytes); > dw_writel(dws, DW_SPI_TXFLTR, txlevel); > > @@ -379,7 +381,7 @@ static int dw_spi_transfer_one(struct spi_controller *master, > return ret; > } > > - if (chip->poll_mode) > + if (chip->poll_mode || !VALID_IRQ(dws->irq)) > return poll_transfer(dws); Please note. The chip->poll and the poll_transfer() methods've been discarded from the driver, since commit 1ceb09717e98 ("spi: dw: remove cs_control and poll_mode members from chip_data"). So you gonna have to get the poll_transfer-like method back. -Sergey > > return 1; > @@ -487,11 +489,13 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) > > spi_controller_set_devdata(master, dws); > > - ret = request_irq(dws->irq, dw_spi_irq, IRQF_SHARED, dev_name(dev), > - master); > - if (ret < 0) { > - dev_err(dev, "can not get IRQ\n"); > - goto err_free_master; > + if (VALID_IRQ(dws->irq)) { > + ret = request_irq(dws->irq, dw_spi_irq, IRQF_SHARED, > + dev_name(dev), master); > + if (ret < 0) { > + dev_err(dev, "can not get IRQ\n"); > + goto err_free_master; > + } > } > > master->use_gpio_descriptors = true; > @@ -539,7 +543,8 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws) > if (dws->dma_ops && dws->dma_ops->dma_exit) > dws->dma_ops->dma_exit(dws); > spi_enable_chip(dws, 0); > - free_irq(dws->irq, master); > + if (VALID_IRQ(dws->irq)) > + free_irq(dws->irq, master); > err_free_master: > spi_controller_put(master); > return ret; > -- > 2.26.2 > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel