Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758793AbcJYL5E (ORCPT ); Tue, 25 Oct 2016 07:57:04 -0400 Received: from mga11.intel.com ([192.55.52.93]:37009 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753576AbcJYL5C (ORCPT ); Tue, 25 Oct 2016 07:57:02 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,545,1473145200"; d="scan'208";a="893715131" Date: Tue, 25 Oct 2016 14:50:25 +0300 From: Mika Westerberg To: tnhuynh@apm.com Cc: Jarkko Nikula , Andy Shevchenko , Wolfram Sang , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, Loc Ho , Thang Nguyen , Phong Vo , patches@apm.com Subject: Re: [PATCH v1] I2C Designware Core Supports SMBUS BLOCK Message-ID: <20161025115025.GI1476@lahna.fi.intel.com> References: <1477370113-15145-1-git-send-email-tnhuynh@apm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1477370113-15145-1-git-send-email-tnhuynh@apm.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4584 Lines: 138 On Tue, Oct 25, 2016 at 11:35:13AM +0700, tnhuynh@apm.com wrote: > From: Tin Huynh > > Free and Open IPMI use SMBUS BLOCK Read/Write to support SSIF protocol. > However, I2C Designwave Core Driver doesn't handle the case at the moment. > The below patch supports this feature. > > Signed-off-by: Tin Huynh > --- > drivers/i2c/busses/i2c-designware-core.c | 42 +++++++++++++++++++++++++-- > drivers/i2c/busses/i2c-designware-platdrv.c | 1 + > 2 files changed, 40 insertions(+), 3 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c > index 1fe93c4..3abf0e5 100644 > --- a/drivers/i2c/busses/i2c-designware-core.c > +++ b/drivers/i2c/busses/i2c-designware-core.c > @@ -588,8 +588,17 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) > * detected from the registers so we set it always > * when writing/reading the last byte. > */ > + > + /* > + * i2c-core.c always set the buffer length of > + * I2C_FUNC_SMBUS_BLOCK_DATA to 1. The length will > + * be adjusted when receiving the first byte. > + * Thus we can't stop the transaction here. > + */ > + No empty line here. > if (dev->msg_write_idx == dev->msgs_num - 1 && > - buf_len == 1) > + buf_len == 1 && > + !(msgs[dev->msg_write_idx].flags & I2C_M_RECV_LEN)) Why not store flags somewhere in local variable. Then you do not need the ugly line splitting above. So instead if (dev->msg_write_idx == dev->msgs_num -1 && buf_len == 1 && !(flags & I2C_M_RECV_LEN)) but even that starts to require small helper function, I think. > cmd |= BIT(9); > > if (need_restart) { > @@ -614,7 +623,14 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) > dev->tx_buf = buf; > dev->tx_buf_len = buf_len; > > - if (buf_len > 0) { > + /* > + * Because we don't know the buffer length in the > + * I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop > + * the transcation here. ^^^^^^^^^^^ transaction > + */ > + No empty line here. > + if (buf_len > 0 || > + msgs[dev->msg_write_idx].flags & I2C_M_RECV_LEN) { Here also same comments about "flags". > /* more bytes to be written */ > dev->status |= STATUS_WRITE_IN_PROGRESS; > break; > @@ -659,7 +675,27 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev) > rx_valid = dw_readl(dev, DW_IC_RXFLR); > > for (; len > 0 && rx_valid > 0; len--, rx_valid--) { > - *buf++ = dw_readl(dev, DW_IC_DATA_CMD); > + *buf = dw_readl(dev, DW_IC_DATA_CMD); > + /* ensure length byte is a valid value */ > + if (msgs[dev->msg_read_idx].flags & I2C_M_RECV_LEN > + && *buf <= I2C_SMBUS_BLOCK_MAX && *buf > 0) { And here. Also you have " " between I2C_SMBUS_BLOCK_MAX and &&. > + /* > + * Adjust the buffer length and mask the flag > + * after receiving the first byte > + */ > + msgs[dev->msg_read_idx].flags &= > + ~I2C_M_RECV_LEN; And here. Actually you should move the whole block into a helper function. > + len = *buf + 1; > + /* Increase one with PEC flag */ > + if (msgs[dev->msg_read_idx].flags & > + I2C_CLIENT_PEC) > + len++; > + > + dev->tx_buf_len = len > dev->rx_outstanding ? > + len - dev->rx_outstanding : 0; > + msgs[dev->msg_read_idx].len = len; > + } > + buf++; > dev->rx_outstanding--; > } > > diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c > index 0b42a12..886fb62 100644 > --- a/drivers/i2c/busses/i2c-designware-platdrv.c > +++ b/drivers/i2c/busses/i2c-designware-platdrv.c > @@ -220,6 +220,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev) > I2C_FUNC_SMBUS_BYTE | > I2C_FUNC_SMBUS_BYTE_DATA | > I2C_FUNC_SMBUS_WORD_DATA | > + I2C_FUNC_SMBUS_BLOCK_DATA | > I2C_FUNC_SMBUS_I2C_BLOCK; > > dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE | > -- > 1.7.1 > > > -- > CONFIDENTIALITY NOTICE: This e-mail message, including any attachments, is > for the sole use of the intended recipient(s) and contains information that > is confidential and proprietary to Applied Micro Circuits Corporation or > its subsidiaries. It is to be used solely for the purpose of furthering the > parties' business relationship. All unauthorized review, use, disclosure or > distribution is prohibited. If you are not the intended recipient, please > contact the sender by reply e-mail and destroy all copies of the original > message. Yeah, right.