From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S966927AbdAEKzd (ORCPT ); Thu, 5 Jan 2017 05:55:33 -0500 Received: from atl4mhfb04.myregisteredsite.com ([209.17.115.120]:53380 "EHLO atl4mhfb04.myregisteredsite.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1761695AbdAEKyQ (ORCPT ); Thu, 5 Jan 2017 05:54:16 -0500 X-Greylist: delayed 348 seconds by postgrey-1.27 at vger.kernel.org; Thu, 05 Jan 2017 05:53:24 EST X-TCPREMOTEIP: 37.74.225.130 X-Authenticated-UID: mike@milosoftware.com From: Mike Looijmans To: linux-i2c@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, wsa@the-dreams.de, soren.brinkmann@xilinx.com, michal.simek@xilinx.com, Mike Looijmans Subject: [PATCH] i2c: i2c-cadence: Don't register the adapter until it's ready Date: Thu, 5 Jan 2017 11:47:20 +0100 Message-Id: <1483613240-32501-1-git-send-email-mike.looijmans@topic.nl> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The driver calls i2c_add_adapter before writing to config registers, resulting in dmesg output like this, where devices fail to initialize: cdns-i2c ff030000.i2c: timeout waiting on completion pca953x 1-0041: failed reading register pca953x: probe of 1-0041 failed with error -110 at24 1-0050: 512 byte 24c04 EEPROM, writable, 1 bytes/write cdns-i2c ff030000.i2c: 100 kHz mmio ff030000 irq 197 The adapter is being used before it completed the "probe". To fix this, make "i2c_add_adapter" the last thing it calls in probe. It also makes sense to show the adapter initialization before the devices on the bus. Signed-off-by: Mike Looijmans --- drivers/i2c/busses/i2c-cadence.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c index 6869712..7793bb8 100644 --- a/drivers/i2c/busses/i2c-cadence.c +++ b/drivers/i2c/busses/i2c-cadence.c @@ -962,10 +962,6 @@ static int cdns_i2c_probe(struct platform_device *pdev) goto err_clk_dis; } - ret = i2c_add_adapter(&id->adap); - if (ret < 0) - goto err_clk_dis; - /* * Cadence I2C controller has a bug wherein it generates * invalid read transaction after HW timeout in master receiver mode. @@ -978,6 +974,10 @@ static int cdns_i2c_probe(struct platform_device *pdev) dev_info(&pdev->dev, "%u kHz mmio %08lx irq %d\n", id->i2c_clk / 1000, (unsigned long)r_mem->start, id->irq); + ret = i2c_add_adapter(&id->adap); + if (ret < 0) + goto err_clk_dis; + return 0; err_clk_dis: -- 1.9.1