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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT 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 98A49C433E0 for ; Fri, 22 Jan 2021 20:08:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57DE123AFC for ; Fri, 22 Jan 2021 20:08:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730964AbhAVUIz (ORCPT ); Fri, 22 Jan 2021 15:08:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:35776 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728338AbhAVONF (ORCPT ); Fri, 22 Jan 2021 09:13:05 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id ADE1623A82; Fri, 22 Jan 2021 14:09:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1611324593; bh=9bRbA/jQkhFE5WIgUpWAVFL7tJg0TwZ4oyz8ZblzCgY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eF0Sacfpw+wfvlulMqn+krRQpHZ4rjwkHqRHrgzoW09Krxx4d7BOPVAkRym9gjPRJ 9nLzZUk09GJ0X7Ibnr1UALVl5Lh9GoLkDTFavkTGHoa95mChutcRM3kuofWHxkvqmw IGmpvlfWj94CLWdrWwIiiZ7hQ4cKwZueHICdrbA8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Hennerich , Alexandru Ardelean , Mark Brown Subject: [PATCH 4.4 31/31] spi: cadence: cache reference clock rate during probe Date: Fri, 22 Jan 2021 15:08:45 +0100 Message-Id: <20210122135733.110337130@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210122135731.873346566@linuxfoundation.org> References: <20210122135731.873346566@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michael Hennerich commit 4d163ad79b155c71bf30366dc38f8d2502f78844 upstream. The issue is that using SPI from a callback under the CCF lock will deadlock, since this code uses clk_get_rate(). Fixes: c474b38665463 ("spi: Add driver for Cadence SPI controller") Signed-off-by: Michael Hennerich Signed-off-by: Alexandru Ardelean Link: https://lore.kernel.org/r/20210114154217.51996-1-alexandru.ardelean@analog.com Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spi-cadence.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/spi/spi-cadence.c +++ b/drivers/spi/spi-cadence.c @@ -116,6 +116,7 @@ struct cdns_spi { void __iomem *regs; struct clk *ref_clk; struct clk *pclk; + unsigned int clk_rate; u32 speed_hz; const u8 *txbuf; u8 *rxbuf; @@ -257,7 +258,7 @@ static void cdns_spi_config_clock_freq(s u32 ctrl_reg, baud_rate_val; unsigned long frequency; - frequency = clk_get_rate(xspi->ref_clk); + frequency = xspi->clk_rate; ctrl_reg = cdns_spi_read(xspi, CDNS_SPI_CR_OFFSET); @@ -557,8 +558,9 @@ static int cdns_spi_probe(struct platfor master->set_cs = cdns_spi_chipselect; master->mode_bits = SPI_CPOL | SPI_CPHA; + xspi->clk_rate = clk_get_rate(xspi->ref_clk); /* Set to default valid value */ - master->max_speed_hz = clk_get_rate(xspi->ref_clk) / 4; + master->max_speed_hz = xspi->clk_rate / 4; xspi->speed_hz = master->max_speed_hz; master->bits_per_word_mask = SPI_BPW_MASK(8);