From patchwork Thu Jul 9 03:25:47 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sricharan Ramabadhran X-Patchwork-Id: 6752671 X-Patchwork-Delegate: agross@codeaurora.org Return-Path: X-Original-To: patchwork-linux-arm-msm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 5ED2EC05AC for ; Thu, 9 Jul 2015 03:27:16 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6180D20660 for ; Thu, 9 Jul 2015 03:27:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3865D205E7 for ; Thu, 9 Jul 2015 03:27:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753205AbbGID0Z (ORCPT ); Wed, 8 Jul 2015 23:26:25 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:41824 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753396AbbGID0T (ORCPT ); Wed, 8 Jul 2015 23:26:19 -0400 Received: from smtp.codeaurora.org (localhost [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 063AF140D7A; Thu, 9 Jul 2015 03:26:19 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 486) id E668E140D83; Thu, 9 Jul 2015 03:26:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from blr-ubuntu-32.ap.qualcomm.com (unknown [202.46.23.61]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: sricharan@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id C5FB8140D7E; Thu, 9 Jul 2015 03:26:14 +0000 (UTC) From: Sricharan R To: iivanov@mm-sol.com, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, galak@codeaurora.org, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, agross@codeaurora.org, dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org Cc: sricharan@codeaurora.org Subject: [PATCH V4 4/7] i2c: qup: Transfer each i2c_msg in i2c_msgs without a stop bit Date: Thu, 9 Jul 2015 08:55:47 +0530 Message-Id: <1436412350-19519-5-git-send-email-sricharan@codeaurora.org> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1436412350-19519-1-git-send-email-sricharan@codeaurora.org> References: <1436412350-19519-1-git-send-email-sricharan@codeaurora.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The definition of i2c_msg says that "If this is the last message in a group, it is followed by a STOP. Otherwise it is followed by the next @i2c_msg transaction segment, beginning with a (repeated) START" So the expectation is that there is no 'STOP' bit inbetween individual i2c_msg segments with repeated 'START'. The QUP i2c hardware has no way to inform that there should not be a 'STOP' at the end of transaction. The only way to implement this is to coalesce all the i2c_msg in i2c_msgs in to one transaction and transfer them. Adding the support for the same. This is required for some clients like touchscreen which keeps incrementing counts across individual transfers and 'STOP' bit inbetween resets the counter, which is not required. This patch adds the support in non-dma mode. Signed-off-by: Sricharan R --- drivers/i2c/busses/i2c-qup.c | 40 ++++++++++++++++++++++++++++++---------- 1 file changed, 30 insertions(+), 10 deletions(-) diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c index a4e20d9..c0757d9 100644 --- a/drivers/i2c/busses/i2c-qup.c +++ b/drivers/i2c/busses/i2c-qup.c @@ -113,6 +113,7 @@ #define SET_BIT 0x1 #define RESET_BIT 0x0 #define ONE_BYTE 0x1 +#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31) struct qup_i2c_block { int count; @@ -121,6 +122,7 @@ struct qup_i2c_block { int rx_tag_len; int data_len; u8 tags[6]; + int config_run; }; struct qup_i2c_dev { @@ -152,6 +154,10 @@ struct qup_i2c_dev { int (*qup_i2c_write_one)(struct qup_i2c_dev *qup, struct i2c_msg *msg); + /* Current i2c_msg in i2c_msgs */ + int cmsg; + /* total num of i2c_msgs */ + int num; int (*qup_i2c_read_one)(struct qup_i2c_dev *qup, struct i2c_msg *msg); @@ -278,7 +284,8 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, status = readl(qup->base + QUP_I2C_STATUS); if (((opflags & op) >> shift) == val) { - if (op == QUP_OUT_NOT_EMPTY) { + if ((op == QUP_OUT_NOT_EMPTY) && + (qup->cmsg == (qup->num - 1))) { if (!(status & I2C_STATUS_BUS_ACTIVE)) return 0; } else { @@ -301,12 +308,14 @@ static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) if (total < qup->out_fifo_sz) { /* FIFO mode */ writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE); - writel(total, qup->base + QUP_MX_WRITE_CNT); + writel(total | qup->blk.config_run, + qup->base + QUP_MX_WRITE_CNT); } else { /* BLOCK mode (transfer data on chunks) */ writel(QUP_OUTPUT_BLK_MODE | QUP_REPACK_EN, qup->base + QUP_IO_MODE); - writel(total, qup->base + QUP_MX_OUTPUT_CNT); + writel(total | qup->blk.config_run, + qup->base + QUP_MX_OUTPUT_CNT); } } @@ -374,6 +383,9 @@ static void qup_i2c_get_blk_data(struct qup_i2c_dev *qup, /* There are 2 tag bytes that are read in to fifo for every block */ if (msg->flags & I2C_M_RD) qup->blk.rx_tag_len = qup->blk.count * 2; + + if (qup->cmsg) + qup->blk.config_run = QUP_I2C_MX_CONFIG_DURING_RUN; } static int qup_i2c_send_data(struct qup_i2c_dev *qup, int tlen, u8 *tbuf, @@ -440,7 +452,8 @@ static int qup_i2c_get_tags(u8 *tags, struct qup_i2c_dev *qup, } /* Send _STOP commands for the last block */ - if (qup->blk.pos == (qup->blk.count - 1)) { + if (qup->blk.pos == (qup->blk.count - 1) + && (qup->cmsg == (qup->num - 1))) { if (msg->flags & I2C_M_RD) tags[len++] = QUP_TAG_V2_DATARD_STOP; else @@ -571,7 +584,6 @@ static int qup_i2c_write(struct qup_i2c_dev *qup, struct i2c_msg *msg) goto err; ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE); - err: disable_irq(qup->irq); qup->msg = NULL; @@ -584,18 +596,19 @@ static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len) int tx_len = qup->blk.tx_tag_len; len += qup->blk.rx_tag_len; + tx_len |= qup->blk.config_run; if (len < qup->in_fifo_sz) { /* FIFO mode */ writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE); - writel(len, qup->base + QUP_MX_READ_CNT); writel(tx_len, qup->base + QUP_MX_WRITE_CNT); + writel(len | qup->blk.config_run, qup->base + QUP_MX_READ_CNT); } else { /* BLOCK mode (transfer data on chunks) */ writel(QUP_INPUT_BLK_MODE | QUP_REPACK_EN, qup->base + QUP_IO_MODE); - writel(len, qup->base + QUP_MX_INPUT_CNT); writel(tx_len, qup->base + QUP_MX_OUTPUT_CNT); + writel(len | qup->blk.config_run, qup->base + QUP_MX_INPUT_CNT); } } @@ -770,6 +783,8 @@ static int qup_i2c_xfer(struct i2c_adapter *adap, struct qup_i2c_dev *qup = i2c_get_adapdata(adap); int ret, idx; + qup->num = 1; + ret = pm_runtime_get_sync(qup->dev); if (ret < 0) goto out; @@ -823,6 +838,9 @@ static int qup_i2c_xfer_v2(struct i2c_adapter *adap, struct qup_i2c_dev *qup = i2c_get_adapdata(adap); int ret, idx; + qup->num = num; + qup->cmsg = 0; + ret = pm_runtime_get_sync(qup->dev); if (ret < 0) goto out; @@ -854,13 +872,15 @@ static int qup_i2c_xfer_v2(struct i2c_adapter *adap, else ret = qup_i2c_write(qup, &msgs[idx]); - if (!ret) - ret = qup_i2c_change_state(qup, QUP_RESET_STATE); - if (ret) break; + + qup->cmsg++; } + if (!ret) + ret = qup_i2c_change_state(qup, QUP_RESET_STATE); + if (ret == 0) ret = num; out: