From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ray Jui Subject: Re: [PATCH v1 1/1] i2c: iproc: Fix i2c master read more than 63 bytes Date: Tue, 30 Jul 2019 13:53:24 -0700 Message-ID: <8b8d83ce-70ba-eacd-7ea3-6f8425f1e0fc@broadcom.com> References: <1563956907-21255-1-git-send-email-rayagonda.kokatanur@broadcom.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1563956907-21255-1-git-send-email-rayagonda.kokatanur@broadcom.com> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Rayagonda Kokatanur , Wolfram Sang , Rob Herring , Mark Rutland Cc: linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, bcm-kernel-feedback-list@broadcom.com, Florian Fainelli List-Id: devicetree@vger.kernel.org Hi Rayagonda, On 7/24/2019 1:28 AM, Rayagonda Kokatanur wrote: > Use SMBUS_MASTER_DATA_READ.MASTER_RD_STATUS bit to check for RX > FIFO empty condition because SMBUS_MASTER_FIFO_CONTROL.MASTER_RX_PKT_COUNT > is not updated for read >= 64 bytes. This fixes the issue when trying to > read from the I2C slave more than 63 bytes. > > Fixes: c24b8d574b7c ("i2c: iproc: Extend I2C read up to 255 bytes") > > Signed-off-by: Rayagonda Kokatanur > --- > drivers/i2c/busses/i2c-bcm-iproc.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c > index 2c7f145..d7fd76b 100644 > --- a/drivers/i2c/busses/i2c-bcm-iproc.c > +++ b/drivers/i2c/busses/i2c-bcm-iproc.c > @@ -392,16 +392,18 @@ static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c, > static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c) > { > struct i2c_msg *msg = iproc_i2c->msg; > + uint32_t val; > > /* Read valid data from RX FIFO */ > while (iproc_i2c->rx_bytes < msg->len) { > - if (!((iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET) >> M_FIFO_RX_CNT_SHIFT) > - & M_FIFO_RX_CNT_MASK)) > + val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET); > + > + /* rx fifo empty */ > + if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK)) > break; > > msg->buf[iproc_i2c->rx_bytes] = > - (iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET) >> > - M_RX_DATA_SHIFT) & M_RX_DATA_MASK; > + (val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK; > iproc_i2c->rx_bytes++; > } > } > Thanks for the fix. This fix looks good to me! Reviewed-by: Ray Jui