[PATCH v5 1/5] i2c: hpe: Add GXP SoC I2C Controller

nick.hawkins
2023-02-17T15:57:05Z

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 <nick.hawkins@hpe.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>

---

v5:
*Remove use of i2c_global_init_done
*Removed use of if else case for inline conditional
*Removed error messages for timeouts and NACKS
*Added bit definitions to replace magic values
*Fix build error
*Relocate Kconfig definition
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 | 620 +++++++++++++++++++++++++++++++++++
3 files changed, 628 insertions(+)
create mode 100644 drivers/i2c/busses/i2c-gxp.c

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index e50f9603d189..8b95aaab9e97 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -659,6 +659,13 @@ config I2C_GPIO_FAULT_INJECTOR
faults to an I2C bus, so another bus master can be stress-tested.
This is for debugging. If unsure, say 'no'.

+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.
+
config I2C_HIGHLANDER
tristate "Highlander FPGA SMBus interface"
depends on SH_HIGHLANDER || COMPILE_TEST
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..da4c8e5a8039
--- /dev/null
+++ b/drivers/i2c/busses/i2c-gxp.c
@@ -0,0 +1,620 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (C) 2022 Hewlett-Packard Enterprise Development Company, L.P. */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#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
+
+/* I2CSCMD Bits */
+#define SNOOP_EVT_CLR 0x80
+#define SLAVE_EVT_CLR 0x40
+#define SNOOP_EVT_MASK 0x20
+#define SLAVE_EVT_MASK 0x10
+#define SLAVE_ACK_ENAB 0x08
+#define SLAVE_EVT_STALL 0x01
+
+/* I2CMCMD Bits */
+#define MASTER_EVT_CLR 0x80
+#define MASTER_ACK_ENAB 0x08
+#define RW_CMD 0x04
+#define STOP_CMD 0x02
+#define START_CMD 0x01
+
+/* I2CTMOEDG value */
+#define GXP_DATA_EDGE_RST_CTRL 0x0a /* 30ns */
+
+/* I2CFLTFAIR Bits */
+#define FILTER_CNT 0x30
+#define FAIRNESS_CNT 0x02
+
+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;
+
+ /* Read or Write */
+ value |= drvdata->curr_msg->flags & I2C_M_RD ? RW_CMD | START_CMD : START_CMD;
+
+ 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:
+ break;
+ case GXP_I2C_RDATA_PHASE:
+ break;
+ case GXP_I2C_ADDR_PHASE:
+ break;
+ default:
+ break;
+ }
+ return -ETIMEDOUT;
+ }
+
+ if (drvdata->state == GXP_I2C_ADDR_NACK ||
+ drvdata->state == GXP_I2C_DATA_NACK)
+ 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(SLAVE_EVT_CLR | SNOOP_EVT_MASK | SLAVE_ACK_ENAB |
+ SLAVE_EVT_STALL, 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(SNOOP_EVT_CLR | SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_EVT_MASK, 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(MASTER_EVT_CLR | STOP_CMD, 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 |= MASTER_EVT_CLR | RW_CMD | START_CMD;
+ } else {
+ /* Write and clear master event */
+ value |= MASTER_EVT_CLR | START_CMD;
+ }
+
+ 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(MASTER_EVT_CLR | RW_CMD,
+ drvdata->base + GXP_I2CMCMD);
+ } else {
+ /* Read data and ack it */
+ writeb(MASTER_EVT_CLR | MASTER_ACK_ENAB |
+ RW_CMD, 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 |= MASTER_EVT_CLR;
+ 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(MASTER_EVT_CLR | RW_CMD,
+ drvdata->base + GXP_I2CMCMD);
+ } else {
+ /* Read data and ack it */
+ writeb(MASTER_EVT_CLR | MASTER_ACK_ENAB |
+ RW_CMD, 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 |= MASTER_EVT_CLR;
+ 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(SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_ACK_ENAB | SLAVE_EVT_STALL, 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 | (SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_EVT_STALL);
+ 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(SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_ACK_ENAB | SLAVE_EVT_STALL,
+ drvdata->base + GXP_I2CSCMD);
+ } else {
+ /* Nack next byte from master */
+ writeb(SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_EVT_STALL, 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 | (SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_EVT_STALL);
+ writew(value, drvdata->base + GXP_I2CSCMD);
+ } else {
+ /* No more bytes needed */
+ writew(SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_ACK_ENAB | SLAVE_EVT_STALL,
+ 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(SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_ACK_ENAB | SLAVE_EVT_STALL,
+ drvdata->base + GXP_I2CSCMD);
+ } else {
+ /* Nack next byte from master */
+ writeb(SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_EVT_STALL, 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(FILTER_CNT | FAIRNESS_CNT,
+ drvdata->base + GXP_I2CFLTFAIR);
+ writeb(GXP_DATA_EDGE_RST_CTRL, drvdata->base + GXP_I2CTMOEDG);
+ writeb(0x00, drvdata->base + GXP_I2CCYCTIM);
+ writeb(0x00, drvdata->base + GXP_I2CSNPAA);
+ writeb(0x00, drvdata->base + GXP_I2CADVFEAT);
+ writeb(SNOOP_EVT_CLR | SLAVE_EVT_CLR | SNOOP_EVT_MASK |
+ SLAVE_EVT_MASK, drvdata->base + GXP_I2CSCMD);
+ writeb(MASTER_EVT_CLR, 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 (!i2cg_map) {
+ 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);
+ }
+
+ 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 = ((size_t)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 <nick.hawkins@hpe.com>");
+MODULE_DESCRIPTION("HPE GXP I2C bus driver");
+MODULE_LICENSE("GPL");