From patchwork Thu Apr 21 21:32:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Ceresoli X-Patchwork-Id: 12822443 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50FE9C433F5 for ; Thu, 21 Apr 2022 21:33:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1442073AbiDUVgq (ORCPT ); Thu, 21 Apr 2022 17:36:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57344 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231443AbiDUVgp (ORCPT ); Thu, 21 Apr 2022 17:36:45 -0400 Received: from relay3-d.mail.gandi.net (relay3-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::223]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DAD544A901; Thu, 21 Apr 2022 14:33:53 -0700 (PDT) Received: from melee.fritz.box (unknown [77.244.183.192]) (Authenticated sender: luca.ceresoli@bootlin.com) by mail.gandi.net (Postfix) with ESMTPA id A93E760004; Thu, 21 Apr 2022 21:33:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1650576830; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=H1SCxsyir0yk12O74c3/slnu+DY/q/kHFuNIUrrfPek=; b=llanma7UwoiWXapTlRDnbMcAwLIiConDmuSs+6G2cs7QkoRu+9RoLDI1H5nFuuUG2fqm89 j2RVWDIIwQqPOoxWN+wpWlgJIfMKBgHZ+RnbcGDoBi26WGrgC5tw/1km48rbzFGxqXAvVX 5fCIIJ+EXKIPiulUfuomVxw8MJsVdCZbBqOfmNcC0AzN4Lwqw/Ppao7CGdkz6j+G9bbf8r JX678bAwQ9T5C18Gd4pV89DKf+3iTPV4nf1mhv8nveuZZhCHE7zTvKBPQGWaAxGX2gaN/T C26/bx0Q1TBb9oq9WL7+D9gMVnVHAMnR5d3CsI5TkPg8Vt5l093unA6EtiaO5A== From: Luca Ceresoli To: linux-spi@vger.kernel.org Cc: Luca Ceresoli , Mark Brown , Heiko Stuebner , Chris Ruehl , linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] spi: rockchip: fix missing error on unsupported SPI_CS_HIGH Date: Thu, 21 Apr 2022 23:32:51 +0200 Message-Id: <20220421213251.1077899-1-luca.ceresoli@bootlin.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org The hardware (except for the ROCKCHIP_SPI_VER2_TYPE2 version) does not support active-high native chip selects. However if such a CS is configured the core does not error as it normally should, because the 'ctlr->use_gpio_descriptors = true' line in rockchip_spi_probe() makes the core set SPI_CS_HIGH in ctlr->mode_bits. In such a case the spi-rockchip driver operates normally but produces an active-low chip select signal without notice. There is no provision in the current core code to handle this situation. Fix by adding a check in the ctlr->setup function (similarly to what spi-atmel.c does). This cannot be done reading the SPI_CS_HIGH but in ctlr->mode_bits because that bit gets always set by the core for master mode (see above). Fixes: eb1262e3cc8b ("spi: spi-rockchip: use num-cs property and ctlr->enable_gpiods") Signed-off-by: Luca Ceresoli --- drivers/spi/spi-rockchip.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index cdc16eecaf6b..a08215eb9e14 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -196,6 +196,8 @@ struct rockchip_spi { bool slave_abort; bool cs_inactive; /* spi slave tansmition stop when cs inactive */ + bool cs_high_supported; /* native CS supports active-high polarity */ + struct spi_transfer *xfer; /* Store xfer temporarily */ }; @@ -719,6 +721,11 @@ static int rockchip_spi_setup(struct spi_device *spi) struct rockchip_spi *rs = spi_controller_get_devdata(spi->controller); u32 cr0; + if (!spi->cs_gpiod && (spi->mode & SPI_CS_HIGH) && !rs->cs_high_supported) { + dev_warn(&spi->dev, "setup: non GPIO CS can't be active-high\n"); + return -EINVAL; + } + pm_runtime_get_sync(rs->dev); cr0 = readl_relaxed(rs->regs + ROCKCHIP_SPI_CTRLR0); @@ -899,6 +906,7 @@ static int rockchip_spi_probe(struct platform_device *pdev) switch (readl_relaxed(rs->regs + ROCKCHIP_SPI_VERSION)) { case ROCKCHIP_SPI_VER2_TYPE2: + rs->cs_high_supported = true; ctlr->mode_bits |= SPI_CS_HIGH; if (ctlr->can_dma && slave_mode) rs->cs_inactive = true;