Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757261AbbGGO21 (ORCPT ); Tue, 7 Jul 2015 10:28:27 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:34812 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751757AbbGGO2S (ORCPT ); Tue, 7 Jul 2015 10:28:18 -0400 From: Roger Quadros To: , , CC: , , , , Roger Quadros Subject: [PATCH 1/2] net: can: c_can: Fix default pinmux glitch at init Date: Tue, 7 Jul 2015 17:27:56 +0300 Message-ID: <1436279277-3386-2-git-send-email-rogerq@ti.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1436279277-3386-1-git-send-email-rogerq@ti.com> References: <1436279277-3386-1-git-send-email-rogerq@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1960 Lines: 53 From: "J.D. Schroeder" The previous change 3973c526ae9c (net: can: c_can: Disable pins when CAN interface is down) causes a slight glitch on the pinctrl settings when used. Since commit ab78029 (drivers/pinctrl: grab default handles from device core), the device core will automatically set the default pins. This causes the pins to be momentarily set to the default and then to the sleep state in register_c_can_dev(). By adding an optional "enable" state, boards can set the default pin state to be disabled and avoid the glitch when the switch from default to sleep first occurs. If the "enable" state is not available c_can_pinctrl_select_state() falls back to using the "default" pinctrl state. [Roger Q] - Forward port to v4.2 Signed-off-by: J.D. Schroeder Signed-off-by: Roger Quadros --- drivers/net/can/c_can/c_can.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c index 041525d..66e98e7 100644 --- a/drivers/net/can/c_can/c_can.c +++ b/drivers/net/can/c_can/c_can.c @@ -605,7 +605,18 @@ static int c_can_start(struct net_device *dev) priv->can.state = CAN_STATE_ERROR_ACTIVE; /* activate pins */ - pinctrl_pm_select_default_state(dev->dev.parent); +#ifdef CONFIG_PINCTRL + if (priv->device->pins) { + struct pinctrl_state *s; + + /* Attempt to use "active" if available else use "default" */ + s = pinctrl_lookup_state(priv->device->pins->p, "active"); + if (!IS_ERR(s)) + pinctrl_select_state(priv->device->pins->p, s); + else + pinctrl_pm_select_default_state(dev->dev.parent); + } +#endif return 0; } -- 2.1.4 -- 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/