From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sifan Naeem Subject: [PATCH v3 6/7] i2c: img-scb: Clear line and interrupt status before starting a transfer Date: Thu, 10 Sep 2015 15:50:06 +0100 Message-ID: <1441896607-16310-7-git-send-email-sifan.naeem@imgtec.com> References: <1441896607-16310-1-git-send-email-sifan.naeem@imgtec.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1441896607-16310-1-git-send-email-sifan.naeem-1AXoQHu6uovQT0dZR+AlfA@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Wolfram Sang , James Hogan , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Ezequiel Garcia Cc: Ionela Voinescu , Sifan Naeem List-Id: linux-i2c@vger.kernel.org Clear line status and all generated interrupts from the interrupt status register before starting a transfer, as we may have unserviced interrupts from previous transfers that might be handled in the context of the new transfer. Fixes: commit 27bce457d588 ("i2c: img-scb: Add Imagination Technologies I2C SCB driver") Signed-off-by: Sifan Naeem Acked-by: James Hogan Reviewed-by: James Hartley --- drivers/i2c/busses/i2c-img-scb.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/i2c/busses/i2c-img-scb.c b/drivers/i2c/busses/i2c-img-scb.c index 049d193d01ac..0fa47158dbe4 100644 --- a/drivers/i2c/busses/i2c-img-scb.c +++ b/drivers/i2c/busses/i2c-img-scb.c @@ -1060,6 +1060,15 @@ static int img_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, i2c->last_msg = (i == num - 1); reinit_completion(&i2c->msg_complete); + /* + * Clear line status and all interrupts before starting a + * transfer, as we may have unserviced interrupts from + * previous transfers that might be handled in the context + * of the new transfer. + */ + img_i2c_writel(i2c, SCB_INT_CLEAR_REG, ~0); + img_i2c_writel(i2c, SCB_CLEAR_REG, ~0); + if (atomic) img_i2c_atomic_start(i2c); else if (msg->flags & I2C_M_RD) -- 1.7.9.5