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[2620:137:e000::1:20]) by mx.google.com with ESMTP id nl12-20020a17090b384c00b0022bb70dd01asi3334912pjb.87.2023.01.25.10.49.13; Wed, 25 Jan 2023 10:49:26 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@hpe.com header.s=pps0720 header.b=jIqTQLtb; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=hpe.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235867AbjAYSrW (ORCPT + 99 others); Wed, 25 Jan 2023 13:47:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40020 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235341AbjAYSrK (ORCPT ); Wed, 25 Jan 2023 13:47:10 -0500 Received: from mx0a-002e3701.pphosted.com (mx0a-002e3701.pphosted.com [148.163.147.86]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F33595A829; Wed, 25 Jan 2023 10:47:06 -0800 (PST) Received: from pps.filterd (m0134422.ppops.net [127.0.0.1]) by mx0b-002e3701.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 30PIV230015117; Wed, 25 Jan 2023 18:46:45 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=hpe.com; h=from : to : subject : date : message-id : in-reply-to : references; s=pps0720; bh=pQtra/WobKd101GoyU/4O1i0e//dQv+Zr0Gr+L9maCs=; b=jIqTQLtbIXhuXayEn0ebIdxo0q19SHX/Z7zH5Jm4WWvdOsT7CuqORNNY1hdO9+YKQ8Qi gPkm2XpnZRHUqllO7PW4RN+xKxpQXYS+dkZFdfoZyneF57ZHdqA4gFKOPAmiuBycKw/S ZaPcyOvTz0ZyAt1nbvMXm/AZOBNj+a/pljPteeJ1cvN3eLMnTUOXyvTASvkeQKTmNFeF HC4FrzLpZ2yDKpq9tSoo33KIASkdCOhG4TTrbdZZMT7pc6ofrryMYL13PFcGJle+waTD EKnYTLjkgl2R1LwJ2zIRq3zHdDjt5mY86gT+oiwxsqkvzZNDGbOO5S6KsE7e7jCa4TQB xg== Received: from p1lg14881.it.hpe.com (p1lg14881.it.hpe.com [16.230.97.202]) by mx0b-002e3701.pphosted.com (PPS) with ESMTPS id 3nb9s10597-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 25 Jan 2023 18:46:45 +0000 Received: from p1lg14885.dc01.its.hpecorp.net (unknown [10.119.18.236]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by p1lg14881.it.hpe.com (Postfix) with ESMTPS id 349B5802B86; Wed, 25 Jan 2023 18:46:44 +0000 (UTC) Received: from hpe.com (unknown [16.231.227.36]) by p1lg14885.dc01.its.hpecorp.net (Postfix) with ESMTP id 77019808D86; Wed, 25 Jan 2023 18:46:43 +0000 (UTC) From: nick.hawkins@hpe.com To: verdun@hpe.com, nick.hawkins@hpe.com, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, linux@armlinux.org.uk, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, joel@jms.id.au Subject: [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller Date: Wed, 25 Jan 2023 12:44:34 -0600 Message-Id: <20230125184438.28483-2-nick.hawkins@hpe.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20230125184438.28483-1-nick.hawkins@hpe.com> References: <20230125184438.28483-1-nick.hawkins@hpe.com> X-Proofpoint-GUID: xhUJ7xFcXsJl8Pvt6wHxVl5lgdYlCydY X-Proofpoint-ORIG-GUID: xhUJ7xFcXsJl8Pvt6wHxVl5lgdYlCydY X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.930,Hydra:6.0.562,FMLib:17.11.122.1 definitions=2023-01-25_11,2023-01-25_01,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 mlxscore=0 suspectscore=0 impostorscore=0 malwarescore=0 spamscore=0 mlxlogscore=999 adultscore=0 lowpriorityscore=0 phishscore=0 bulkscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2212070000 definitions=main-2301250165 X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1756021460976887936?= X-GMAIL-MSGID: =?utf-8?q?1756021460976887936?= From: Nick Hawkins The GXP SoC supports 10 I2C engines. Each I2C engine is completely independent and can function both as an I2C master and I2C slave. The I2C master can operate in a multi master environment. The engines support a scalable speed from 8kHZ to 1.5 Mhz. Signed-off-by: Nick Hawkins Reviewed-by: Joel Stanley --- v4: *Disable IRQ on device remove by register write *Switch engine variable to u32 v3: *Disable IRQ on device remove *Remove use of I2C_CLASS_DEPRECATED *Use i2c_parse_fw_timings instead of of_property_read_u32 *Remove redundant dev_err_probe as platform_get_irq already has one *Used __iomem instead of res->start to find physical address *Use BIT in gxp_i2c_irq_handler *Made value u8 instead of u16 v2: *Removed rogue tab in structure *Removed use of __iomem base local variables as it was unnecessary *Switched #if IS_ENABLED() -> if (IS_ENABLED()) inside functions *Removed use of pr_* functions *Removed informational prints in register and unregister functions *Removed print from interrupt handler *No informational prints in probe function *Switched dev_err for dev_err_probe in probe function *Use respective helper for mapping the resource to __iomem --- drivers/i2c/busses/Kconfig | 7 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-gxp.c | 603 +++++++++++++++++++++++++++++++++++ 3 files changed, 611 insertions(+) create mode 100644 drivers/i2c/busses/i2c-gxp.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index e50f9603d189..8b3951e0ca5c 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -1457,4 +1457,11 @@ config I2C_VIRTIO This driver can also be built as a module. If so, the module will be called i2c-virtio. +config I2C_GXP + tristate "GXP I2C Interface" + depends on ARCH_HPE_GXP || COMPILE_TEST + help + This enables support for GXP I2C interface. The I2C engines can be + either I2C master or I2C slaves. + endmenu diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index e73cdb1d2b5a..dcc96eab6d68 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -127,6 +127,7 @@ obj-$(CONFIG_I2C_THUNDERX) += i2c-thunderx.o obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o +obj-$(CONFIG_I2C_GXP) += i2c-gxp.o # External I2C/SMBus adapter drivers obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o diff --git a/drivers/i2c/busses/i2c-gxp.c b/drivers/i2c/busses/i2c-gxp.c new file mode 100644 index 000000000000..37272261ce8d --- /dev/null +++ b/drivers/i2c/busses/i2c-gxp.c @@ -0,0 +1,603 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (C) 2022 Hewlett-Packard Enterprise Development Company, L.P. */ + +#include +#include +#include +#include +#include +#include +#include + +#define GXP_MAX_I2C_ENGINE 10 +static const char * const gxp_i2c_name[] = { + "gxp-i2c0", "gxp-i2c1", "gxp-i2c2", "gxp-i2c3", + "gxp-i2c4", "gxp-i2c5", "gxp-i2c6", "gxp-i2c7", + "gxp-i2c8", "gxp-i2c9" }; + +/* GXP I2C Global interrupt status/enable register*/ +#define GXP_I2CINTSTAT 0x00 +#define GXP_I2CINTEN 0x04 + +/* GXP I2C registers */ +#define GXP_I2CSTAT 0x00 +#define MASK_STOP_EVENT 0x20 +#define MASK_ACK 0x08 +#define MASK_RW 0x04 +#define GXP_I2CEVTERR 0x01 +#define MASK_SLAVE_CMD_EVENT 0x01 +#define MASK_SLAVE_DATA_EVENT 0x02 +#define MASK_MASTER_EVENT 0x10 +#define GXP_I2CSNPDAT 0x02 +#define GXP_I2CMCMD 0x04 +#define GXP_I2CSCMD 0x06 +#define GXP_I2CSNPAA 0x09 +#define GXP_I2CADVFEAT 0x0A +#define GXP_I2COWNADR 0x0B +#define GXP_I2CFREQDIV 0x0C +#define GXP_I2CFLTFAIR 0x0D +#define GXP_I2CTMOEDG 0x0E +#define GXP_I2CCYCTIM 0x0F + +static bool i2c_global_init_done; + +enum { + GXP_I2C_IDLE = 0, + GXP_I2C_ADDR_PHASE, + GXP_I2C_RDATA_PHASE, + GXP_I2C_WDATA_PHASE, + GXP_I2C_ADDR_NACK, + GXP_I2C_DATA_NACK, + GXP_I2C_ERROR, + GXP_I2C_COMP +}; + +struct gxp_i2c_drvdata { + struct device *dev; + void __iomem *base; + struct i2c_timings t; + u32 engine; + int irq; + struct completion completion; + struct i2c_adapter adapter; + struct i2c_msg *curr_msg; + int msgs_remaining; + int msgs_num; + u8 *buf; + size_t buf_remaining; + unsigned char state; + struct i2c_client *slave; + unsigned char stopped; +}; + +static struct regmap *i2cg_map; + +static void gxp_i2c_start(struct gxp_i2c_drvdata *drvdata) +{ + u16 value; + + drvdata->buf = drvdata->curr_msg->buf; + drvdata->buf_remaining = drvdata->curr_msg->len; + + /* Note: Address in struct i2c_msg is 7 bits */ + value = drvdata->curr_msg->addr << 9; + + if (drvdata->curr_msg->flags & I2C_M_RD) { + /* Read */ + value |= 0x05; + } else { + /* Write */ + value |= 0x01; + } + + drvdata->state = GXP_I2C_ADDR_PHASE; + writew(value, drvdata->base + GXP_I2CMCMD); +} + +static int gxp_i2c_master_xfer(struct i2c_adapter *adapter, + struct i2c_msg *msgs, int num) +{ + int ret; + struct gxp_i2c_drvdata *drvdata = i2c_get_adapdata(adapter); + unsigned long time_left; + + drvdata->msgs_remaining = num; + drvdata->curr_msg = msgs; + drvdata->msgs_num = num; + reinit_completion(&drvdata->completion); + + gxp_i2c_start(drvdata); + + time_left = wait_for_completion_timeout(&drvdata->completion, + adapter->timeout); + ret = num - drvdata->msgs_remaining; + if (time_left == 0) { + switch (drvdata->state) { + case GXP_I2C_WDATA_PHASE: + dev_err(drvdata->dev, + "gxp_i2c_start:write Data phase timeout at msg[%d]\n", + ret); + break; + case GXP_I2C_RDATA_PHASE: + dev_err(drvdata->dev, + "gxp_i2c_start:read Data phase timeout at msg[%d]\n", + ret); + break; + case GXP_I2C_ADDR_PHASE: + dev_err(drvdata->dev, + "gxp_i2c_start:Addr phase timeout\n"); + break; + default: + dev_err(drvdata->dev, + "gxp_i2c_start:i2c transfer timeout state=%d\n", + drvdata->state); + break; + } + return -ETIMEDOUT; + } + + if (drvdata->state == GXP_I2C_ADDR_NACK) { + dev_err(drvdata->dev, + "gxp_i2c_start:No ACK for address phase\n"); + return -EIO; + } else if (drvdata->state == GXP_I2C_DATA_NACK) { + dev_err(drvdata->dev, "gxp_i2c_start:No ACK for data phase\n"); + return -EIO; + } + + return ret; +} + +static u32 gxp_i2c_func(struct i2c_adapter *adap) +{ + if (IS_ENABLED(CONFIG_I2C_SLAVE)) + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SLAVE; + + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static int gxp_i2c_reg_slave(struct i2c_client *slave) +{ + struct gxp_i2c_drvdata *drvdata = i2c_get_adapdata(slave->adapter); + + if (drvdata->slave) + return -EBUSY; + + if (slave->flags & I2C_CLIENT_TEN) + return -EAFNOSUPPORT; + + drvdata->slave = slave; + + writeb(slave->addr << 1, drvdata->base + GXP_I2COWNADR); + writeb(0x69, drvdata->base + GXP_I2CSCMD); + + return 0; +} + +static int gxp_i2c_unreg_slave(struct i2c_client *slave) +{ + struct gxp_i2c_drvdata *drvdata = i2c_get_adapdata(slave->adapter); + + WARN_ON(!drvdata->slave); + + writeb(0x00, drvdata->base + GXP_I2COWNADR); + writeb(0xF0, drvdata->base + GXP_I2CSCMD); + + drvdata->slave = NULL; + + return 0; +} +#endif + +static const struct i2c_algorithm gxp_i2c_algo = { + .master_xfer = gxp_i2c_master_xfer, + .functionality = gxp_i2c_func, +#if IS_ENABLED(CONFIG_I2C_SLAVE) + .reg_slave = gxp_i2c_reg_slave, + .unreg_slave = gxp_i2c_unreg_slave, +#endif +}; + +static void gxp_i2c_stop(struct gxp_i2c_drvdata *drvdata) +{ + /* Clear event and send stop */ + writeb(0x82, drvdata->base + GXP_I2CMCMD); + + complete(&drvdata->completion); +} + +static void gxp_i2c_restart(struct gxp_i2c_drvdata *drvdata) +{ + u16 value; + + drvdata->buf = drvdata->curr_msg->buf; + drvdata->buf_remaining = drvdata->curr_msg->len; + + value = drvdata->curr_msg->addr << 9; + + if (drvdata->curr_msg->flags & I2C_M_RD) { + /* Read and clear master event */ + value |= 0x85; + } else { + /* Write and clear master event */ + value |= 0x81; + } + + drvdata->state = GXP_I2C_ADDR_PHASE; + + writew(value, drvdata->base + GXP_I2CMCMD); +} + +static void gxp_i2c_chk_addr_ack(struct gxp_i2c_drvdata *drvdata) +{ + u16 value; + + value = readb(drvdata->base + GXP_I2CSTAT); + if (!(value & MASK_ACK)) { + /* Got no ack, stop */ + drvdata->state = GXP_I2C_ADDR_NACK; + gxp_i2c_stop(drvdata); + return; + } + + if (drvdata->curr_msg->flags & I2C_M_RD) { + /* Start to read data from slave */ + if (drvdata->buf_remaining == 0) { + /* No more data to read, stop */ + drvdata->msgs_remaining--; + drvdata->state = GXP_I2C_COMP; + gxp_i2c_stop(drvdata); + return; + } + drvdata->state = GXP_I2C_RDATA_PHASE; + + if (drvdata->buf_remaining == 1) { + /* The last data, do not ack */ + writeb(0x84, drvdata->base + GXP_I2CMCMD); + } else { + /* Read data and ack it */ + writeb(0x8C, drvdata->base + GXP_I2CMCMD); + } + } else { + /* Start to write first data to slave */ + if (drvdata->buf_remaining == 0) { + /* No more data to write, stop */ + drvdata->msgs_remaining--; + drvdata->state = GXP_I2C_COMP; + gxp_i2c_stop(drvdata); + return; + } + value = *drvdata->buf; + value = value << 8; + /* Clear master event */ + value |= 0x80; + drvdata->buf++; + drvdata->buf_remaining--; + drvdata->state = GXP_I2C_WDATA_PHASE; + writew(value, drvdata->base + GXP_I2CMCMD); + } +} + +static void gxp_i2c_ack_data(struct gxp_i2c_drvdata *drvdata) +{ + u8 value; + + /* Store the data returned */ + value = readb(drvdata->base + GXP_I2CSNPDAT); + *drvdata->buf = value; + drvdata->buf++; + drvdata->buf_remaining--; + + if (drvdata->buf_remaining == 0) { + /* No more data, this message is completed. */ + drvdata->msgs_remaining--; + + if (drvdata->msgs_remaining == 0) { + /* No more messages, stop */ + drvdata->state = GXP_I2C_COMP; + gxp_i2c_stop(drvdata); + return; + } + /* Move to next message and start transfer */ + drvdata->curr_msg++; + gxp_i2c_restart(drvdata); + return; + } + + /* Ack the slave to make it send next byte */ + drvdata->state = GXP_I2C_RDATA_PHASE; + if (drvdata->buf_remaining == 1) { + /* The last data, do not ack */ + writeb(0x84, drvdata->base + GXP_I2CMCMD); + } else { + /* Read data and ack it */ + writeb(0x8C, drvdata->base + GXP_I2CMCMD); + } +} + +static void gxp_i2c_chk_data_ack(struct gxp_i2c_drvdata *drvdata) +{ + u16 value; + + value = readb(drvdata->base + GXP_I2CSTAT); + if (!(value & MASK_ACK)) { + /* Received No ack, stop */ + drvdata->state = GXP_I2C_DATA_NACK; + gxp_i2c_stop(drvdata); + return; + } + + /* Got ack, check if there is more data to write */ + if (drvdata->buf_remaining == 0) { + /* No more data, this message is completed */ + drvdata->msgs_remaining--; + + if (drvdata->msgs_remaining == 0) { + /* No more messages, stop */ + drvdata->state = GXP_I2C_COMP; + gxp_i2c_stop(drvdata); + return; + } + /* Move to next message and start transfer */ + drvdata->curr_msg++; + gxp_i2c_restart(drvdata); + return; + } + + /* Write data to slave */ + value = *drvdata->buf; + value = value << 8; + + /* Clear master event */ + value |= 0x80; + drvdata->buf++; + drvdata->buf_remaining--; + drvdata->state = GXP_I2C_WDATA_PHASE; + writew(value, drvdata->base + GXP_I2CMCMD); +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static bool gxp_i2c_slave_irq_handler(struct gxp_i2c_drvdata *drvdata) +{ + u8 value; + u8 buf; + int ret; + + value = readb(drvdata->base + GXP_I2CEVTERR); + + /* Received start or stop event */ + if (value & MASK_SLAVE_CMD_EVENT) { + value = readb(drvdata->base + GXP_I2CSTAT); + /* Master sent stop */ + if (value & MASK_STOP_EVENT) { + if (drvdata->stopped == 0) + i2c_slave_event(drvdata->slave, I2C_SLAVE_STOP, &buf); + writeb(0x69, drvdata->base + GXP_I2CSCMD); + drvdata->stopped = 1; + } else { + /* Master sent start and wants to read */ + drvdata->stopped = 0; + if (value & MASK_RW) { + i2c_slave_event(drvdata->slave, + I2C_SLAVE_READ_REQUESTED, &buf); + value = buf << 8 | 0x61; + writew(value, drvdata->base + GXP_I2CSCMD); + } else { + /* Master wants to write to us */ + ret = i2c_slave_event(drvdata->slave, + I2C_SLAVE_WRITE_REQUESTED, &buf); + if (!ret) { + /* Ack next byte from master */ + writeb(0x69, drvdata->base + GXP_I2CSCMD); + } else { + /* Nack next byte from master */ + writeb(0x61, drvdata->base + GXP_I2CSCMD); + } + } + } + } else if (value & MASK_SLAVE_DATA_EVENT) { + value = readb(drvdata->base + GXP_I2CSTAT); + /* Master wants to read */ + if (value & MASK_RW) { + /* Master wants another byte */ + if (value & MASK_ACK) { + i2c_slave_event(drvdata->slave, + I2C_SLAVE_READ_PROCESSED, &buf); + value = buf << 8 | 0x61; + writew(value, drvdata->base + GXP_I2CSCMD); + } else { + /* No more bytes needed */ + writew(0x69, drvdata->base + GXP_I2CSCMD); + } + } else { + /* Master wants to write to us */ + value = readb(drvdata->base + GXP_I2CSNPDAT); + buf = (uint8_t)value; + ret = i2c_slave_event(drvdata->slave, + I2C_SLAVE_WRITE_RECEIVED, &buf); + if (!ret) { + /* Ack next byte from master */ + writeb(0x69, drvdata->base + GXP_I2CSCMD); + } else { + /* Nack next byte from master */ + writeb(0x61, drvdata->base + GXP_I2CSCMD); + } + } + } else { + return false; + } + + return true; +} +#endif + +static irqreturn_t gxp_i2c_irq_handler(int irq, void *_drvdata) +{ + struct gxp_i2c_drvdata *drvdata = (struct gxp_i2c_drvdata *)_drvdata; + u32 value; + + /* Check if the interrupt is for the current engine */ + regmap_read(i2cg_map, GXP_I2CINTSTAT, &value); + if (!(value & BIT(drvdata->engine))) + return IRQ_NONE; + + value = readb(drvdata->base + GXP_I2CEVTERR); + + /* Error */ + if (value & ~(MASK_MASTER_EVENT | MASK_SLAVE_CMD_EVENT | + MASK_SLAVE_DATA_EVENT)) { + /* Clear all events */ + writeb(0x00, drvdata->base + GXP_I2CEVTERR); + drvdata->state = GXP_I2C_ERROR; + gxp_i2c_stop(drvdata); + return IRQ_HANDLED; + } + + if (IS_ENABLED(CONFIG_I2C_SLAVE)) { + /* Slave mode */ + if (value & (MASK_SLAVE_CMD_EVENT | MASK_SLAVE_DATA_EVENT)) { + if (gxp_i2c_slave_irq_handler(drvdata)) + return IRQ_HANDLED; + return IRQ_NONE; + } + } + + /* Master mode */ + switch (drvdata->state) { + case GXP_I2C_ADDR_PHASE: + gxp_i2c_chk_addr_ack(drvdata); + break; + + case GXP_I2C_RDATA_PHASE: + gxp_i2c_ack_data(drvdata); + break; + + case GXP_I2C_WDATA_PHASE: + gxp_i2c_chk_data_ack(drvdata); + break; + } + + return IRQ_HANDLED; +} + +static void gxp_i2c_init(struct gxp_i2c_drvdata *drvdata) +{ + drvdata->state = GXP_I2C_IDLE; + writeb(2000000 / drvdata->t.bus_freq_hz, + drvdata->base + GXP_I2CFREQDIV); + writeb(0x32, drvdata->base + GXP_I2CFLTFAIR); + writeb(0x0a, drvdata->base + GXP_I2CTMOEDG); + writeb(0x00, drvdata->base + GXP_I2CCYCTIM); + writeb(0x00, drvdata->base + GXP_I2CSNPAA); + writeb(0x00, drvdata->base + GXP_I2CADVFEAT); + writeb(0xF0, drvdata->base + GXP_I2CSCMD); + writeb(0x80, drvdata->base + GXP_I2CMCMD); + writeb(0x00, drvdata->base + GXP_I2CEVTERR); + writeb(0x00, drvdata->base + GXP_I2COWNADR); +} + +static int gxp_i2c_probe(struct platform_device *pdev) +{ + struct gxp_i2c_drvdata *drvdata; + int rc; + struct i2c_adapter *adapter; + + if (!i2c_global_init_done) { + i2cg_map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, + "hpe,sysreg"); + if (IS_ERR(i2cg_map)) { + return dev_err_probe(&pdev->dev, IS_ERR(i2cg_map), + "failed to map i2cg_handle\n"); + } + + /* Disable interrupt */ + regmap_update_bits(i2cg_map, GXP_I2CINTEN, 0x00000FFF, 0); + i2c_global_init_done = true; + } + + drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), + GFP_KERNEL); + if (!drvdata) + return -ENOMEM; + + platform_set_drvdata(pdev, drvdata); + drvdata->dev = &pdev->dev; + init_completion(&drvdata->completion); + + drvdata->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(drvdata->base)) + return PTR_ERR(drvdata->base); + + /* Use physical memory address to determine which I2C engine this is. */ + drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8; + + if (drvdata->engine >= GXP_MAX_I2C_ENGINE) { + return dev_err_probe(&pdev->dev, -EINVAL, "i2c engine% is unsupported\n", + drvdata->engine); + } + + rc = platform_get_irq(pdev, 0); + if (rc < 0) + return rc; + + drvdata->irq = rc; + rc = devm_request_irq(&pdev->dev, drvdata->irq, gxp_i2c_irq_handler, + IRQF_SHARED, gxp_i2c_name[drvdata->engine], drvdata); + if (rc < 0) + return dev_err_probe(&pdev->dev, rc, "irq request failed\n"); + + i2c_parse_fw_timings(&pdev->dev, &drvdata->t, true); + + gxp_i2c_init(drvdata); + + /* Enable interrupt */ + regmap_update_bits(i2cg_map, GXP_I2CINTEN, BIT(drvdata->engine), + BIT(drvdata->engine)); + + adapter = &drvdata->adapter; + i2c_set_adapdata(adapter, drvdata); + + adapter->owner = THIS_MODULE; + strscpy(adapter->name, "HPE GXP I2C adapter", sizeof(adapter->name)); + adapter->algo = &gxp_i2c_algo; + adapter->dev.parent = &pdev->dev; + adapter->dev.of_node = pdev->dev.of_node; + + rc = i2c_add_adapter(adapter); + if (rc) + return dev_err_probe(&pdev->dev, rc, "i2c add adapter failed\n"); + + return 0; +} + +static int gxp_i2c_remove(struct platform_device *pdev) +{ + struct gxp_i2c_drvdata *drvdata = platform_get_drvdata(pdev); + + /* Disable interrupt */ + regmap_update_bits(i2cg_map, GXP_I2CINTEN, BIT(drvdata->engine), 0); + i2c_del_adapter(&drvdata->adapter); + + return 0; +} + +static const struct of_device_id gxp_i2c_of_match[] = { + { .compatible = "hpe,gxp-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, gxp_i2c_of_match); + +static struct platform_driver gxp_i2c_driver = { + .probe = gxp_i2c_probe, + .remove = gxp_i2c_remove, + .driver = { + .name = "gxp-i2c", + .of_match_table = gxp_i2c_of_match, + }, +}; +module_platform_driver(gxp_i2c_driver); + +MODULE_AUTHOR("Nick Hawkins "); +MODULE_DESCRIPTION("HPE GXP I2C bus driver"); +MODULE_LICENSE("GPL");