Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754105AbaDEAYW (ORCPT ); Fri, 4 Apr 2014 20:24:22 -0400 Received: from mail-qg0-f46.google.com ([209.85.192.46]:64698 "EHLO mail-qg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752898AbaDEAYO (ORCPT ); Fri, 4 Apr 2014 20:24:14 -0400 From: Soren Brinkmann To: Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Randy Dunlap , Russell King , Michal Simek , Greg Kroah-Hartman , Jiri Slaby , Grant Likely Cc: Peter Crosthwaite , One Thousand Gnomes , Soren Brinkmann , devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-serial@vger.kernel.org Subject: [RESEND PATCH v3 6/9] tty: xuartps: Don't write IRQ disable register to enable interrupts Date: Fri, 4 Apr 2014 17:23:42 -0700 Message-Id: <1396657425-31029-6-git-send-email-soren.brinkmann@xilinx.com> X-Mailer: git-send-email 1.9.1.1.gbb9f595 In-Reply-To: <1396657425-31029-1-git-send-email-soren.brinkmann@xilinx.com> References: <1396657425-31029-1-git-send-email-soren.brinkmann@xilinx.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A comment states, that, according to the data sheet, to enable interrupts the disable register should be written, but the enable register could be left untouched. And it suspsects a HW bug requiring to write both. Reviewing the data sheet, these statements seem wrong. Just as one would expect. Writing to the enable/disable register enables/disables interrupts. Hence the misleading comment and needless write to the disable register are removed from the enable sequence. Signed-off-by: Soren Brinkmann Tested-by: Michal Simek --- I added a few lines to comment the change and altered the summary line. In case this causes issues it should show up a little easier as a candidate to revert. Changes in v3: None Changes in v2: None --- drivers/tty/serial/xilinx_uartps.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index b182ab8cfd07..f9a2c2fc03c4 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -1085,11 +1085,7 @@ static void xuartps_console_write(struct console *co, const char *s, xuartps_writel(ctrl, XUARTPS_CR_OFFSET); - /* restore interrupt state, it seems like there may be a h/w bug - * in that the interrupt enable register should not need to be - * written based on the data sheet - */ - xuartps_writel(~imr, XUARTPS_IDR_OFFSET); + /* restore interrupt state */ xuartps_writel(imr, XUARTPS_IER_OFFSET); if (locked) -- 1.9.1.1.gbb9f595 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/