From patchwork Wed Jul 3 16:47:32 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?TcOlbnMgUnVsbGfDpXJk?= X-Patchwork-Id: 1126960 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-i2c-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=mansr.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45f6V727nhz9s3Z for ; Thu, 4 Jul 2019 02:47:43 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726825AbfGCQrm (ORCPT ); Wed, 3 Jul 2019 12:47:42 -0400 Received: from unicorn.mansr.com ([81.2.72.234]:58034 "EHLO unicorn.mansr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726430AbfGCQrm (ORCPT ); Wed, 3 Jul 2019 12:47:42 -0400 Received: by unicorn.mansr.com (Postfix, from userid 51770) id 7637C1538A; Wed, 3 Jul 2019 17:47:39 +0100 (BST) From: Mans Rullgard To: linux-i2c@vger.kernel.org Cc: linux-kernel@vger.kernel.org Subject: [RESEND][PATCH] i2c: imx: add support for I2C_M_STOP flag Date: Wed, 3 Jul 2019 17:47:32 +0100 Message-Id: <20190703164732.27973-1-mans@mansr.com> X-Mailer: git-send-email 2.22.0 MIME-Version: 1.0 Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Add support for the I2C_M_STOP flag to the i2c-imx driver. This allows devices requiring a stop between messages to work with this controller. Signed-off-by: Mans Rullgard --- drivers/i2c/busses/i2c-imx.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 7bd409eaf0ac..a7f801bb5dc9 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -908,10 +908,17 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter, /* read/write data */ for (i = 0; i < num; i++) { - if (i == num - 1) - is_lastmsg = true; + if (is_lastmsg) { + /* previous message had I2C_M_STOP flag set */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_MSTA; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + result = i2c_imx_bus_busy(i2c_imx, 1); + if (result) + goto fail0; + } - if (i) { + if (i && !is_lastmsg) { dev_dbg(&i2c_imx->adapter.dev, "<%s> repeated start\n", __func__); temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); @@ -921,6 +928,10 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter, if (result) goto fail0; } + + if (i == num - 1 || (msgs[i].flags & I2C_M_STOP)) + is_lastmsg = true; + dev_dbg(&i2c_imx->adapter.dev, "<%s> transfer message: %d\n", __func__, i); /* write/read data */ @@ -948,6 +959,13 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter, result = i2c_imx_dma_write(i2c_imx, &msgs[i]); else result = i2c_imx_write(i2c_imx, &msgs[i]); + + if (msgs[i].flags & I2C_M_STOP) { + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp &= ~I2CR_MSTA; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + i2c_imx_bus_busy(i2c_imx, 0); + } } if (result) goto fail0; @@ -1034,7 +1052,7 @@ static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx, static u32 i2c_imx_func(struct i2c_adapter *adapter) { - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL + return I2C_FUNC_I2C | I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_READ_BLOCK_DATA; }