Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755251AbbG1Di0 (ORCPT ); Mon, 27 Jul 2015 23:38:26 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:60915 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1754838AbbG1DiY (ORCPT ); Mon, 27 Jul 2015 23:38:24 -0400 X-Listener-Flag: 11101 From: Eddie Huang To: Wolfram Sang CC: , Matthias Brugger , Liguo Zhang , Xudong Chen , Sascha Hauer , , , , , Eddie Huang Subject: [PATCH] i2c: mediatek: fix transfer error handling Date: Tue, 28 Jul 2015 11:38:05 +0800 Message-ID: <1438054685-25214-1-git-send-email-eddie.huang@mediatek.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2913 Lines: 86 From: Liguo Zhang Reset i2c dma engine in hw init function. When occur i2c ack error, mtk_i2c_irq may is twice, first is the ack error interrupt, then the complete interrupt, so i2c->irq_stat need keep the two interrupt value, and only call complete() for the complete interrupt. Signed-off-by: Liguo Zhang Signed-off-by: Eddie Huang --- drivers/i2c/busses/i2c-mt65xx.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index 9920eef..57d11b7 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -59,6 +59,7 @@ #define I2C_DMA_START_EN 0x0001 #define I2C_DMA_INT_FLAG_NONE 0x0000 #define I2C_DMA_CLR_FLAG 0x0000 +#define I2C_DMA_HARD_RST 0x0002 #define I2C_DEFAULT_SPEED 100000 /* hz */ #define MAX_FS_MODE_SPEED 400000 @@ -81,6 +82,7 @@ enum DMA_REGS_OFFSET { OFFSET_INT_FLAG = 0x0, OFFSET_INT_EN = 0x04, OFFSET_EN = 0x08, + OFFSET_RST = 0x0c, OFFSET_CON = 0x18, OFFSET_TX_MEM_ADDR = 0x1c, OFFSET_RX_MEM_ADDR = 0x20, @@ -262,6 +264,10 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c) I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN; writew(control_reg, i2c->base + OFFSET_CONTROL); writew(I2C_DELAY_LEN, i2c->base + OFFSET_DELAY_LEN); + + writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST); + udelay(50); + writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); } /* @@ -550,16 +556,20 @@ err_exit: static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id) { struct mtk_i2c *i2c = dev_id; - u16 restart_flag = 0; + u16 intr_stat = 0; - if (i2c->dev_comp->auto_restart) - restart_flag = I2C_RS_TRANSFER; + intr_stat = readw(i2c->base + OFFSET_INTR_STAT); + writew(intr_stat, i2c->base + OFFSET_INTR_STAT); - i2c->irq_stat = readw(i2c->base + OFFSET_INTR_STAT); - writew(restart_flag | I2C_HS_NACKERR | I2C_ACKERR - | I2C_TRANSAC_COMP, i2c->base + OFFSET_INTR_STAT); + /* + * when occurs i2c ack error, mtk_i2c_irq is called twice, + * first is the ack error interrupt, then the complete interrupt, + * i2c->irq_stat need keep the two interrupt value. + */ + i2c->irq_stat |= intr_stat; - complete(&i2c->msg_complete); + if (i2c->irq_stat & I2C_TRANSAC_COMP) + complete(&i2c->msg_complete); return IRQ_HANDLED; } @@ -729,3 +739,4 @@ module_platform_driver(mtk_i2c_driver); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("MediaTek I2C Bus Driver"); MODULE_AUTHOR("Xudong Chen "); +MODULE_AUTHOR("Liguo Zhang "); -- 1.7.9.5 -- 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/