From patchwork Mon Jul 6 07:18:01 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Kleine-Budde X-Patchwork-Id: 11645011 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1A96C912 for ; Mon, 6 Jul 2020 07:18:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 02D092070C for ; Mon, 6 Jul 2020 07:18:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728826AbgGFHSL (ORCPT ); Mon, 6 Jul 2020 03:18:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728192AbgGFHSL (ORCPT ); Mon, 6 Jul 2020 03:18:11 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 64251C061794 for ; Mon, 6 Jul 2020 00:18:11 -0700 (PDT) Received: from heimdall.vpn.pengutronix.de ([2001:67c:670:205:1d::14] helo=blackshift.org) by metis.ext.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1jsLOA-0004BC-BD; Mon, 06 Jul 2020 09:18:06 +0200 From: Marc Kleine-Budde To: Mark Brown Cc: Maxime Ripard , Chen-Yu Tsai , linux-spi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kernel@pengutronix.de, Marc Kleine-Budde Subject: [PATCH 9/9] spi: spi-sun6i: sun6i_spi_transfer_one(): enable RF_RDY interrupt only if needed Date: Mon, 6 Jul 2020 09:18:01 +0200 Message-Id: <20200706071801.558394-10-mkl@pengutronix.de> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200706071801.558394-1-mkl@pengutronix.de> References: <20200706071801.558394-1-mkl@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:205:1d::14 X-SA-Exim-Mail-From: mkl@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-spi@vger.kernel.org Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org In sun6i_spi_transfer_one() the RX FIFO Ready (SUN6I_INT_CTL_RF_RDY) is unconditionally enabled. A RX interrupt is only needed, if more data than fits into the FIFO is going to be received during this transfer. As the RX-FIFO is drained during transfer complete interrupt, enable the RX FIFO Ready interrupt only if the data doesn't fit into the FIFO. Signed-off-by: Marc Kleine-Budde --- drivers/spi/spi-sun6i.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c index 21b4436a72de..9379ce477bc3 100644 --- a/drivers/spi/spi-sun6i.c +++ b/drivers/spi/spi-sun6i.c @@ -195,7 +195,7 @@ static int sun6i_spi_transfer_one(struct spi_master *master, unsigned int mclk_rate, div, div_cdr1, div_cdr2, timeout; unsigned int start, end, tx_time; unsigned int trig_level; - unsigned int tx_len = 0; + unsigned int tx_len = 0, rx_len = 0; int ret = 0; u32 reg; @@ -250,10 +250,12 @@ static int sun6i_spi_transfer_one(struct spi_master *master, * If it's a TX only transfer, we don't want to fill the RX * FIFO with bogus data */ - if (sspi->rx_buf) + if (sspi->rx_buf) { reg &= ~SUN6I_TFR_CTL_DHB; - else + rx_len = tfr->len; + } else { reg |= SUN6I_TFR_CTL_DHB; + } /* We want to control the chip select manually */ reg |= SUN6I_TFR_CTL_CS_MANUAL; @@ -307,8 +309,10 @@ static int sun6i_spi_transfer_one(struct spi_master *master, sun6i_spi_fill_fifo(sspi); /* Enable the interrupts */ - reg = SUN6I_INT_CTL_TC | SUN6I_INT_CTL_RF_RDY; + reg = SUN6I_INT_CTL_TC; + if (rx_len > sspi->fifo_depth) + reg |= SUN6I_INT_CTL_RF_RDY; if (tx_len > sspi->fifo_depth) reg |= SUN6I_INT_CTL_TF_ERQ;