From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 152ACECDFB3 for ; Tue, 17 Jul 2018 15:31:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C351320877 for ; Tue, 17 Jul 2018 15:31:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C351320877 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.vnet.ibm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730758AbeGQQEg (ORCPT ); Tue, 17 Jul 2018 12:04:36 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:38000 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730621AbeGQQEf (ORCPT ); Tue, 17 Jul 2018 12:04:35 -0400 Received: from pps.filterd (m0098417.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id w6HFTKU3056932 for ; Tue, 17 Jul 2018 11:31:24 -0400 Received: from e36.co.us.ibm.com (e36.co.us.ibm.com [32.97.110.154]) by mx0a-001b2d01.pphosted.com with ESMTP id 2k9h8hnur0-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Tue, 17 Jul 2018 11:31:24 -0400 Received: from localhost by e36.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Tue, 17 Jul 2018 09:31:20 -0600 Received: from b03ledav002.gho.boulder.ibm.com (b03ledav002.gho.boulder.ibm.com [9.17.130.233]) by b03cxnp08026.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id w6HFVJV710682744 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 17 Jul 2018 08:31:19 -0700 Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 28E4A13604F; Tue, 17 Jul 2018 09:31:19 -0600 (MDT) Received: from b03ledav002.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 5763A136051; Tue, 17 Jul 2018 09:31:18 -0600 (MDT) Received: from talon7.ibm.com (unknown [9.41.102.69]) by b03ledav002.gho.boulder.ibm.com (Postfix) with ESMTP; Tue, 17 Jul 2018 09:31:18 -0600 (MDT) From: Eddie James To: linux-i2c@vger.kernel.org Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, wsa@the-dreams.de, robh+dt@kernel.org, benh@kernel.crashing.org, joel@jms.id.au, mark.rutland@arm.com, gregkh@linuxfoundation.org, rdunlap@infradead.org, andy.shevchenko@gmail.com, peda@axentia.se, "eajames@linux.vnet.ibm.com" Subject: [PATCH v12 5/8] i2c: fsi: Add transfer implementation Date: Tue, 17 Jul 2018 10:31:03 -0500 X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1531841466-9833-1-git-send-email-eajames@linux.vnet.ibm.com> References: <1531841466-9833-1-git-send-email-eajames@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 x-cbid: 18071715-0020-0000-0000-00000E3F2FBC X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00009380; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000266; SDB=6.01062145; UDB=6.00545317; IPR=6.00840002; MB=3.00022173; MTD=3.00000008; XFM=3.00000015; UTC=2018-07-17 15:31:23 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18071715-0021-0000-0000-000062507F3D Message-Id: <1531841466-9833-6-git-send-email-eajames@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-07-17_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1806210000 definitions=main-1807170162 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "eajames@linux.vnet.ibm.com" Execute I2C transfers from the FSI-attached I2C master. Use polling instead of interrupts as we have no hardware IRQ over FSI. Signed-off-by: Eddie James Reviewed-by: Andy Shevchenko --- drivers/i2c/busses/i2c-fsi.c | 195 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 193 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-fsi.c b/drivers/i2c/busses/i2c-fsi.c index 0f0bc88..45a6ebd 100644 --- a/drivers/i2c/busses/i2c-fsi.c +++ b/drivers/i2c/busses/i2c-fsi.c @@ -155,6 +155,7 @@ struct fsi_i2c_port { struct i2c_adapter adapter; struct fsi_i2c_master *master; u16 port; + u16 xfrd; }; static int fsi_i2c_read_reg(struct fsi_device *fsi, unsigned int reg, @@ -230,6 +231,99 @@ static int fsi_i2c_set_port(struct fsi_i2c_port *port) return fsi_i2c_write_reg(fsi, I2C_FSI_RESET_ERR, &dummy); } +static int fsi_i2c_start(struct fsi_i2c_port *port, struct i2c_msg *msg, + bool stop) +{ + struct fsi_i2c_master *i2c = port->master; + u32 cmd = I2C_CMD_WITH_START | I2C_CMD_WITH_ADDR; + + port->xfrd = 0; + + if (msg->flags & I2C_M_RD) + cmd |= I2C_CMD_READ; + + if (stop || msg->flags & I2C_M_STOP) + cmd |= I2C_CMD_WITH_STOP; + + cmd |= FIELD_PREP(I2C_CMD_ADDR, msg->addr); + cmd |= FIELD_PREP(I2C_CMD_LEN, msg->len); + + return fsi_i2c_write_reg(i2c->fsi, I2C_FSI_CMD, &cmd); +} + +static int fsi_i2c_get_op_bytes(int op_bytes) +{ + /* fsi is limited to max 4 byte aligned ops */ + if (op_bytes > 4) + return 4; + else if (op_bytes == 3) + return 2; + return op_bytes; +} + +static int fsi_i2c_write_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg, + u8 fifo_count) +{ + int write; + int rc; + struct fsi_i2c_master *i2c = port->master; + int bytes_to_write = i2c->fifo_size - fifo_count; + int bytes_remaining = msg->len - port->xfrd; + + bytes_to_write = min(bytes_to_write, bytes_remaining); + + while (bytes_to_write) { + write = fsi_i2c_get_op_bytes(bytes_to_write); + + rc = fsi_device_write(i2c->fsi, I2C_FSI_FIFO, + &msg->buf[port->xfrd], write); + if (rc) + return rc; + + port->xfrd += write; + bytes_to_write -= write; + } + + return 0; +} + +static int fsi_i2c_read_fifo(struct fsi_i2c_port *port, struct i2c_msg *msg, + u8 fifo_count) +{ + int read; + int rc; + struct fsi_i2c_master *i2c = port->master; + int bytes_to_read; + int xfr_remaining = msg->len - port->xfrd; + u32 dummy; + + bytes_to_read = min_t(int, fifo_count, xfr_remaining); + + while (bytes_to_read) { + read = fsi_i2c_get_op_bytes(bytes_to_read); + + if (xfr_remaining) { + rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, + &msg->buf[port->xfrd], read); + if (rc) + return rc; + + port->xfrd += read; + xfr_remaining -= read; + } else { + /* no more buffer but data in fifo, need to clear it */ + rc = fsi_device_read(i2c->fsi, I2C_FSI_FIFO, &dummy, + read); + if (rc) + return rc; + } + + bytes_to_read -= read; + } + + return 0; +} + static int fsi_i2c_reset_engine(struct fsi_i2c_master *i2c, u16 port) { int rc; @@ -305,17 +399,114 @@ static int fsi_i2c_abort(struct fsi_i2c_port *port, u32 status) return -ETIMEDOUT; } +static int fsi_i2c_handle_status(struct fsi_i2c_port *port, + struct i2c_msg *msg, u32 status) +{ + int rc; + u8 fifo_count; + + if (status & I2C_STAT_ERR) { + rc = fsi_i2c_abort(port, status); + if (rc) + return rc; + + if (status & I2C_STAT_INV_CMD) + return -EINVAL; + + if (status & (I2C_STAT_PARITY | I2C_STAT_BE_OVERRUN | + I2C_STAT_BE_ACCESS)) + return -EPROTO; + + if (status & I2C_STAT_NACK) + return -ENXIO; + + if (status & I2C_STAT_LOST_ARB) + return -EAGAIN; + + if (status & I2C_STAT_STOP_ERR) + return -EBADMSG; + + return -EIO; + } + + if (status & I2C_STAT_DAT_REQ) { + fifo_count = FIELD_GET(I2C_STAT_FIFO_COUNT, status); + + if (msg->flags & I2C_M_RD) + return fsi_i2c_read_fifo(port, msg, fifo_count); + + return fsi_i2c_write_fifo(port, msg, fifo_count); + } + + if (status & I2C_STAT_CMD_COMP) { + if (port->xfrd < msg->len) + return -ENODATA; + + return msg->len; + } + + return 0; +} + +static int fsi_i2c_wait(struct fsi_i2c_port *port, struct i2c_msg *msg, + unsigned long timeout) +{ + u32 status = 0; + int rc; + unsigned long start = jiffies; + + do { + rc = fsi_i2c_read_reg(port->master->fsi, I2C_FSI_STAT, + &status); + if (rc) + return rc; + + if (status & I2C_STAT_ANY_RESP) { + rc = fsi_i2c_handle_status(port, msg, status); + if (rc < 0) + return rc; + + /* cmd complete and all data xfrd */ + if (rc == msg->len) + return 0; + + /* need to xfr more data, but maybe don't need wait */ + continue; + } + + usleep_range(I2C_CMD_SLEEP_MIN_US, I2C_CMD_SLEEP_MAX_US); + } while (time_after(start + timeout, jiffies)); + + return -ETIMEDOUT; +} + static int fsi_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { - int rc; + int i, rc; + unsigned long start_time; struct fsi_i2c_port *port = adap->algo_data; + struct i2c_msg *msg; rc = fsi_i2c_set_port(port); if (rc) return rc; - return -EOPNOTSUPP; + for (i = 0; i < num; i++) { + msg = msgs + i; + start_time = jiffies; + + rc = fsi_i2c_start(port, msg, i == num - 1); + if (rc) + return rc; + + rc = fsi_i2c_wait(port, msg, + adap->timeout - (jiffies - start_time)); + if (rc) + return rc; + } + + return num; } static u32 fsi_i2c_functionality(struct i2c_adapter *adap) -- 1.8.3.1