From patchwork Tue Sep 27 11:57:02 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Noralf_Tr=C3=B8nnes?= X-Patchwork-Id: 9351775 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 47BFA6077B for ; Tue, 27 Sep 2016 12:02:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 38A35291B2 for ; Tue, 27 Sep 2016 12:02:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2BEA3291BD; Tue, 27 Sep 2016 12:02:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 6E1E6291B2 for ; Tue, 27 Sep 2016 12:01:59 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bor3g-0003wy-Aw; Tue, 27 Sep 2016 12:00:24 +0000 Received: from smtp.domeneshop.no ([2a01:5b40:0:3005::1]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bor1d-0002Cd-Vb; Tue, 27 Sep 2016 11:58:22 +0000 Received: from 211.81-166-168.customer.lyse.net ([81.166.168.211]:34833 helo=localhost.localdomain) by smtp.domeneshop.no with esmtpsa (TLS1.1:DHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1bor1C-0005in-TV; Tue, 27 Sep 2016 13:57:50 +0200 From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= To: wsa@the-dreams.de, swarren@wwwdotorg.org, eric@anholt.net Subject: [PATCH v2 4/8] i2c: bcm2835: Can't support I2C_M_IGNORE_NAK Date: Tue, 27 Sep 2016 13:57:02 +0200 Message-Id: <1474977426-3272-5-git-send-email-noralf@tronnes.org> X-Mailer: git-send-email 2.8.2 In-Reply-To: <1474977426-3272-1-git-send-email-noralf@tronnes.org> References: <1474977426-3272-1-git-send-email-noralf@tronnes.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160927_045818_429608_ADA23020 X-CRM114-Status: UNSURE ( 7.66 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-rpi-kernel@lists.infradead.org, =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The controller can't support this flag, so remove it. Documentation/i2c/i2c-protocol states that all of the message is sent: I2C_M_IGNORE_NAK: Normally message is interrupted immediately if there is [NA] from the client. Setting this flag treats any [NA] as [A], and all of message is sent. From the BCM2835 ARM Peripherals datasheet: The ERR field is set when the slave fails to acknowledge either its address or a data byte written to it. So when the controller doesn't receive an ack, it sets ERR and raises an interrupt. In other words, the whole message is not sent. Signed-off-by: Noralf Trønnes --- drivers/i2c/busses/i2c-bcm2835.c | 4 ---- 1 file changed, 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c index 370a322..4e08add 100644 --- a/drivers/i2c/busses/i2c-bcm2835.c +++ b/drivers/i2c/busses/i2c-bcm2835.c @@ -203,10 +203,6 @@ static int bcm2835_i2c_xfer_msg(struct bcm2835_i2c_dev *i2c_dev, if (likely(!i2c_dev->msg_err)) return 0; - if ((i2c_dev->msg_err & BCM2835_I2C_S_ERR) && - (msg->flags & I2C_M_IGNORE_NAK)) - return 0; - dev_err_ratelimited(i2c_dev->dev, "i2c transfer failed: %x\n", i2c_dev->msg_err);