From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 980173AFCF4; Sat, 17 Oct 2026 16:48:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792255690; cv=none; b=Q1QaipkbdRXV8fm1Dqqb3RhWhxWaVGGkmxKU8CvZrsnOtZIvyEfJbJm22y5ShZcVSw2zqgeDRZkmv787wwWYtdIqIcMVEPxX7ylAVCOofjCN7k7JIKJJN04jp1dE8821nD4WQHtfM7r4h9Uvove5FEdYjMq+I2lAVEyEqvBsteA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792255690; c=relaxed/simple; bh=se3hFAdJL40R9BVVoDf6VATartNgF4fmnR/K6pAF38o=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=m5buORg97cgLPhk5apfMlElyJaS1wT30rJwaWOxuWUfWrT0j/QtRALTIRSrqEhKXcsvY1lN6fyBtr/87oUAgzrkJIToWCW3DBFb7p09tbyaTY4VqIzxO1HxQ6ZPepZYz3PkTjlPmHCTSK4065jGZaZo1tT/bPJS7tM7HK/twNYI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zgBjKR7e; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zgBjKR7e" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E4EE71F000C4; Sat, 17 Oct 2026 16:48:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792255689; bh=+nYNjQMjAJwNM9YkAF2XFTK8a9tvTdAL02LCeGpIGdw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=zgBjKR7eu5r7UimYnRidiEMixLaCYMFBv8KiY2Bce9/Vwa1rahAWZ8qCt4DMXrsqn 6mIiaRc3vIXCgp8FxVvIlIEfs0T/43u9fZY9rapj8+XSWOAgmRwwl5/rhTAjIx23oN ey85VHHgeFNwnrAvjf/Ic7PAErG+t7Cl/Yy045ZM= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Stanley Chu , Alexandre Belloni , Sasha Levin Subject: [PATCH 6.12 859/869] i3c: master: svc: Fix npcm845 FIFO_EMPTY quirk Date: Sat, 17 Oct 2026 18:01:40 +0200 Message-ID: <20261017160058.882462456@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261017160036.979869304@linuxfoundation.org> References: <20261017160036.979869304@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stanley Chu [ Upstream commit bc4a09d8e79cadccdd505f47b01903a80bc666e7 ] In a private write transfer, the driver pre-fills the FIFO to work around the FIFO_EMPTY quirk. However, if an IBIWON event occurs, the hardware emits a NACK and the driver initiates a retry. During the retry, driver attempts to pre-fill the FIFO again if there is remaining data, but since the FIFO is already full, this leads to data loss. Check available space in FIFO to prevent overflow. Fixes: 4008a74e0f9b ("i3c: master: svc: Fix npcm845 FIFO empty issue") Signed-off-by: Stanley Chu Link: https://lore.kernel.org/r/20250730003719.1825593-1-yschu@nuvoton.com Signed-off-by: Alexandre Belloni Signed-off-by: Sasha Levin --- drivers/i3c/master/svc-i3c-master.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c index 25cdb77973c09..26e53717b8292 100644 --- a/drivers/i3c/master/svc-i3c-master.c +++ b/drivers/i3c/master/svc-i3c-master.c @@ -103,6 +103,7 @@ #define SVC_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL GENMASK(5, 4) #define SVC_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY 0 #define SVC_I3C_MDATACTRL_RXCOUNT(x) FIELD_GET(GENMASK(28, 24), (x)) +#define SVC_I3C_MDATACTRL_TXCOUNT(x) FIELD_GET(GENMASK(20, 16), (x)) #define SVC_I3C_MDATACTRL_TXFULL BIT(30) #define SVC_I3C_MDATACTRL_RXEMPTY BIT(31) @@ -1285,14 +1286,19 @@ static int svc_i3c_master_xfer(struct svc_i3c_master *master, * FIFO start filling as soon as possible after EmitStartAddr. */ if (svc_has_quirk(master, SVC_I3C_QUIRK_FIFO_EMPTY) && !rnw && xfer_len) { - u32 end = xfer_len > SVC_I3C_FIFO_SIZE ? 0 : SVC_I3C_MWDATAB_END; - u32 len = min_t(u32, xfer_len, SVC_I3C_FIFO_SIZE); - - writesb(master->regs + SVC_I3C_MWDATAB1, out, len - 1); - /* Mark END bit if this is the last byte */ - writel(out[len - 1] | end, master->regs + SVC_I3C_MWDATAB); - xfer_len -= len; - out += len; + u32 space, end, len; + + reg = readl(master->regs + SVC_I3C_MDATACTRL); + space = SVC_I3C_FIFO_SIZE - SVC_I3C_MDATACTRL_TXCOUNT(reg); + if (space) { + end = xfer_len > space ? 0 : SVC_I3C_MWDATAB_END; + len = min_t(u32, xfer_len, space); + writesb(master->regs + SVC_I3C_MWDATAB1, out, len - 1); + /* Mark END bit if this is the last byte */ + writel(out[len - 1] | end, master->regs + SVC_I3C_MWDATAB); + xfer_len -= len; + out += len; + } } ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg, -- 2.53.0