From patchwork Thu Jul 16 08:08:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rayagonda Kokatanur X-Patchwork-Id: 1330041 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-i2c-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=quarantine dis=none) header.from=broadcom.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=broadcom.com header.i=@broadcom.com header.a=rsa-sha256 header.s=google header.b=gyYRQVs7; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4B6n2m1m1mz9sRW for ; Thu, 16 Jul 2020 18:09:04 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726885AbgGPIJC (ORCPT ); Thu, 16 Jul 2020 04:09:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45154 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726873AbgGPIJA (ORCPT ); Thu, 16 Jul 2020 04:09:00 -0400 Received: from mail-pg1-x543.google.com (mail-pg1-x543.google.com [IPv6:2607:f8b0:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2DFEAC08C5C0 for ; Thu, 16 Jul 2020 01:09:00 -0700 (PDT) Received: by mail-pg1-x543.google.com with SMTP id k27so4472856pgm.2 for ; Thu, 16 Jul 2020 01:09:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=aCGGactJae57qbbpYq++cFizr8LPhk+6s9WIHNZJ04M=; b=gyYRQVs7B8rmkhComuQRCcJpLDEtIx8vxhDmau+6R2aE5Q5MdT3CM/RdY/j0v9jZF+ KwtzTbBXKD0F3ABDzmqXSEvGouXyCrNujVr9fZ/sCrw6ata/aQq/hOHhf1npzTRchpRS +L4OsbBx5DEXz/FYoqJCpx0QOUST0xnjM69Lg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=aCGGactJae57qbbpYq++cFizr8LPhk+6s9WIHNZJ04M=; b=bXOQCThGfJKKrlXYHAFQbUg6scvqu2WP9YuFuP4IfuOOxVZIxTisBxbEj/1mvhMfx7 hPX3lDWIv8WCVoqyPiyMHguJ9tMR/pgLlH3SrkcpEt4d8gnJk05qVyHPmmhERAOBz38Z EJmEmXE47ucEEpqKtyPxmTkAIZ8KfPwIDishCxlFgP14apH6muv3LmqphuaoMD+i6hWu dqYwCZ5+V9ZKF0xUJJRg3Df4jTQJ1b42Ys7QlO9IJdQH1iAvRQtd52RTbOwWUe1ne+ZQ GEgpE0KDhJi6nQtUuP2oozhyI3uQACHIBng/n/LSMlDkAl5h3+2w+/FMPANR8lCnYehc hg3w== X-Gm-Message-State: AOAM532iL+6CtEr+jQpUctNMjeCQaEYZgl98s/iR/F8TxMnTvGLycctY 3CtoQwIooOlXwb1Ola4F5oNQBygIst8= X-Google-Smtp-Source: ABdhPJzY89owDrFh1Z8KnO6xelQRBmWpGhbIDfhY7bcls9gGw1PkpgX/IgpGYwIRWXuRLq7oDoIdPw== X-Received: by 2002:aa7:9f8f:: with SMTP id z15mr2592603pfr.73.1594886939485; Thu, 16 Jul 2020 01:08:59 -0700 (PDT) Received: from rayagonda.dhcp.broadcom.net ([192.19.234.250]) by smtp.gmail.com with ESMTPSA id a3sm4353085pgd.73.2020.07.16.01.08.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Jul 2020 01:08:58 -0700 (PDT) From: Rayagonda Kokatanur To: Wolfram Sang , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Ray Jui , Scott Branden , bcm-kernel-feedback-list@broadcom.com, Lori Hikichi , Robert Richter , Nishka Dasgupta , Andy Shevchenko , linux-arm-kernel@lists.infradead.org Cc: Rayagonda Kokatanur Subject: [PATCH V1 2/2] i2c: iproc: add slave pec support Date: Thu, 16 Jul 2020 13:38:36 +0530 Message-Id: <20200716080836.2279-3-rayagonda.kokatanur@broadcom.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200716080836.2279-1-rayagonda.kokatanur@broadcom.com> References: <20200716080836.2279-1-rayagonda.kokatanur@broadcom.com> Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Iproc supports PEC computation and checking in both Master and Slave mode. This patch adds support for PEC in slave mode. Signed-off-by: Rayagonda Kokatanur --- drivers/i2c/busses/i2c-bcm-iproc.c | 50 +++++++++++++++++++++++++++--- 1 file changed, 46 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c index 8a3c98866fb7..51c8b165bb5e 100644 --- a/drivers/i2c/busses/i2c-bcm-iproc.c +++ b/drivers/i2c/busses/i2c-bcm-iproc.c @@ -93,6 +93,7 @@ #define S_CMD_STATUS_MASK 0x07 #define S_CMD_STATUS_SUCCESS 0x0 #define S_CMD_STATUS_TIMEOUT 0x5 +#define S_CMD_PEC_SHIFT 8 #define IE_OFFSET 0x38 #define IE_M_RX_FIFO_FULL_SHIFT 31 @@ -138,7 +139,9 @@ #define S_RX_OFFSET 0x4c #define S_RX_STATUS_SHIFT 30 #define S_RX_STATUS_MASK 0x03 -#define S_RX_PEC_ERR_SHIFT 29 +#define S_RX_PEC_ERR_SHIFT 28 +#define S_RX_PEC_ERR_MASK 0x3 +#define S_RX_PEC_ERR 0x1 #define S_RX_DATA_SHIFT 0 #define S_RX_DATA_MASK 0xff @@ -205,6 +208,8 @@ struct bcm_iproc_i2c_dev { /* bytes that have been read */ unsigned int rx_bytes; unsigned int thld_bytes; + + bool en_s_pec; }; /* @@ -321,6 +326,24 @@ static void bcm_iproc_i2c_check_slave_status( } } +static int bcm_iproc_smbus_check_slave_pec(struct bcm_iproc_i2c_dev *iproc_i2c, + u32 val) +{ + u8 err_status; + int ret = 0; + + if (!iproc_i2c->en_s_pec) + return ret; + + err_status = (u8)((val >> S_RX_PEC_ERR_SHIFT) & S_RX_PEC_ERR_MASK); + if (err_status == S_RX_PEC_ERR) { + dev_err(iproc_i2c->device, "Slave PEC error\n"); + ret = -EBADMSG; + } + + return ret; +} + static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c, u32 status) { @@ -347,6 +370,8 @@ static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c, iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value); val = BIT(S_CMD_START_BUSY_SHIFT); + if (iproc_i2c->en_s_pec) + val |= BIT(S_CMD_PEC_SHIFT); iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val); /* @@ -361,9 +386,19 @@ static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c, value = (u8)((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK); i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_WRITE_RECEIVED, &value); - if (rx_status == I2C_SLAVE_RX_END) - i2c_slave_event(iproc_i2c->slave, - I2C_SLAVE_STOP, &value); + if (rx_status == I2C_SLAVE_RX_END) { + int ret; + + ret = bcm_iproc_smbus_check_slave_pec(iproc_i2c, + val); + if (!ret) + i2c_slave_event(iproc_i2c->slave, + I2C_SLAVE_STOP, &value); + else + i2c_slave_event(iproc_i2c->slave, + I2C_SLAVE_PEC_ERR, + &value); + } } } else if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) { /* Master read other than start */ @@ -372,6 +407,8 @@ static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c, iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value); val = BIT(S_CMD_START_BUSY_SHIFT); + if (iproc_i2c->en_s_pec) + val |= BIT(S_CMD_PEC_SHIFT); iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val); } @@ -1065,6 +1102,11 @@ static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave) if (slave->flags & I2C_CLIENT_TEN) return -EAFNOSUPPORT; + /* Enable partial slave HW PEC support if requested by the client */ + iproc_i2c->en_s_pec = !!(slave->flags & I2C_CLIENT_PEC); + if (iproc_i2c->en_s_pec) + dev_info(iproc_i2c->device, "Enable PEC\n"); + iproc_i2c->slave = slave; bcm_iproc_i2c_slave_init(iproc_i2c, false); return 0;