From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiner Kallweit Subject: [PATCH 07/12] i2c: meson: improve interrupt handler and detect spurious interrupts Date: Wed, 8 Mar 2017 07:47:16 +0100 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wr0-f195.google.com ([209.85.128.195]:36049 "EHLO mail-wr0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756730AbdCHGus (ORCPT ); Wed, 8 Mar 2017 01:50:48 -0500 Received: by mail-wr0-f195.google.com with SMTP id l37so2832526wrc.3 for ; Tue, 07 Mar 2017 22:50:45 -0800 (PST) In-Reply-To: Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: Wolfram Sang Cc: "linux-i2c@vger.kernel.org" , linux-amlogic@lists.infradead.org If state is STATE_IDLE no interrupt should occur. Detect this case and warn. In addition move resetting REG_CTRL_START bit to the start of the interrupt handler and remove a unneeded REG_CTRL_START bit reset in meson_i2c_xfer_msg. Signed-off-by: Heiner Kallweit --- drivers/i2c/busses/i2c-meson.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c index 81304840..b3b881f9 100644 --- a/drivers/i2c/busses/i2c-meson.c +++ b/drivers/i2c/busses/i2c-meson.c @@ -233,7 +233,15 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id) dev_dbg(i2c->dev, "irq: state %d, pos %d, count %d, ctrl %08x\n", i2c->state, i2c->pos, i2c->count, ctrl); - if (ctrl & REG_CTRL_ERROR && i2c->state != STATE_IDLE) { + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); + + if (i2c->state == STATE_IDLE) { + dev_notice(i2c->dev, "spurious interrupt detected\n"); + spin_unlock(&i2c->lock); + return IRQ_NONE; + } + + if (ctrl & REG_CTRL_ERROR) { /* * The bit is set when the IGNORE_NAK bit is cleared * and the device didn't respond. In this case, the @@ -276,15 +284,12 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id) i2c->state = STATE_IDLE; complete(&i2c->done); break; - case STATE_IDLE: - break; } out: if (i2c->state != STATE_IDLE) { /* Restart the processing */ meson_i2c_write_tokens(i2c); - meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, REG_CTRL_START); } @@ -344,9 +349,6 @@ static int meson_i2c_xfer_msg(struct meson_i2c *i2c, struct i2c_msg *msg, */ spin_lock_irqsave(&i2c->lock, flags); - /* Abort any active operation */ - meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); - if (!time_left) { i2c->state = STATE_IDLE; ret = -ETIMEDOUT; -- 2.12.0