From patchwork Mon Aug 23 13:05:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kewei Xu X-Patchwork-Id: 501659 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, 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 7D571C432BE for ; Mon, 23 Aug 2021 13:05:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EB83613AD for ; Mon, 23 Aug 2021 13:05:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237272AbhHWNGc (ORCPT ); Mon, 23 Aug 2021 09:06:32 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:53818 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S237164AbhHWNGb (ORCPT ); Mon, 23 Aug 2021 09:06:31 -0400 X-UUID: 113cba8d4ec64a4ba5f8e2a8d3c28c7a-20210823 X-UUID: 113cba8d4ec64a4ba5f8e2a8d3c28c7a-20210823 Received: from mtkcas10.mediatek.inc [(172.21.101.39)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 896504563; Mon, 23 Aug 2021 21:05:44 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Mon, 23 Aug 2021 21:05:42 +0800 Received: from localhost.localdomain (10.17.3.153) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Mon, 23 Aug 2021 21:05:41 +0800 From: Kewei Xu To: CC: , , , , , , , , , , , , , , Subject: [PATCH 2/7] i2c: mediatek: Reset the handshake signal between i2c and dma Date: Mon, 23 Aug 2021 21:05:32 +0800 Message-ID: <1629723937-10839-3-git-send-email-kewei.xu@mediatek.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1629723937-10839-1-git-send-email-kewei.xu@mediatek.com> References: <1629723937-10839-1-git-send-email-kewei.xu@mediatek.com> MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Due to changes in the hardware design of the handshaking signal between i2c and dma, it is necessary to reset the handshaking signal before each transfer to ensure that the multi-msgs can be transferred correctly. Signed-off-by: Kewei Xu --- drivers/i2c/busses/i2c-mt65xx.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index 2661ed0..abda525 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -47,6 +48,9 @@ #define I2C_RD_TRANAC_VALUE 0x0001 #define I2C_SCL_MIS_COMP_VALUE 0x0000 #define I2C_CHN_CLR_FLAG 0x0000 +#define I2C_CLR_DEBUGCTR 0x0000 +#define I2C_RELIABILITY 0x0010 +#define I2C_DMAACK_ENABLE 0x0008 #define I2C_DMA_CON_TX 0x0000 #define I2C_DMA_CON_RX 0x0001 @@ -842,6 +846,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, u16 restart_flag = 0; u16 dma_sync = 0; u32 reg_4g_mode; + u32 reg_dma_reset; u8 *dma_rd_buf = NULL; u8 *dma_wr_buf = NULL; dma_addr_t rpaddr = 0; @@ -855,6 +860,27 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, reinit_completion(&i2c->msg_complete); + if (i2c->dev_comp->apdma_sync && left_num > 1) { + mtk_i2c_writew(i2c, I2C_CLR_DEBUGCTR, OFFSET_DEBUGCTRL); + writel(I2C_DMA_HANDSHAKE_RST | I2C_DMA_WARM_RST, + i2c->pdmabase + OFFSET_RST); + + ret = readw_poll_timeout(i2c->pdmabase + OFFSET_RST, + reg_dma_reset, + !(reg_dma_reset & I2C_DMA_WARM_RST), + 0, 100); + if (ret) { + dev_err(i2c->dev, "DMA warm reset timeout\n"); + return -ETIMEDOUT; + } + + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); + mtk_i2c_writew(i2c, I2C_HANDSHAKE_RST, OFFSET_SOFTRESET); + mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_SOFTRESET); + mtk_i2c_writew(i2c, I2C_RELIABILITY | I2C_DMAACK_ENABLE, + OFFSET_DEBUGCTRL); + } + control_reg = mtk_i2c_readw(i2c, OFFSET_CONTROL) & ~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS); if ((i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) || (left_num >= 1))