* [PATCH v4 0/5] ARM: Add GXP I2C Support
@ 2023-01-25 18:44 ` nick.hawkins
0 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
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.
---
Changes since v3:
*Switch engine variable to u32
*Disable IRQ on device remove with register write instead
*Provided even greater description with the use of Phandle
Changes since v2:
*Disable IRQ on a 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 for u8 read
*Provided a better description of Phandle in yaml
Changes since v1:
*Removed yaml documentation of hpe,gxp-sysreg as it has been
applied to syscon.yaml
*Made i2cX a generic node name i2c in dts file
*Added status field to the dtsi and the dts for i2c bus
*Removed unnecessary size-cells and address-cells from yaml
*Removed phandle from hpe,sysreg-phandle
*Changed hpe,i2c-max-bus-freq to clock-frequency
*Removed rogue tab in structure definition
*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
*Removed informational prints from probe function
*Switched dev_err -> dev_err_probe in probe function
*Used the respective helper for mapping the resource to
__iomem
Nick Hawkins (5):
i2c: hpe: Add GXP SoC I2C Controller
dt-bindings: i2c: Add hpe,gxp-i2c
ARM: dts: hpe: Add I2C Topology
ARM: multi_v7_defconfig: add gxp i2c module
MAINTAINERS: Add HPE GXP I2C Support
.../devicetree/bindings/i2c/hpe,gxp-i2c.yaml | 59 ++
MAINTAINERS | 2 +
arch/arm/boot/dts/hpe-bmc-dl360gen10.dts | 109 ++++
arch/arm/boot/dts/hpe-gxp.dtsi | 125 ++++
arch/arm/configs/multi_v7_defconfig | 1 +
drivers/i2c/busses/Kconfig | 7 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-gxp.c | 603 ++++++++++++++++++
8 files changed, 907 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
create mode 100644 drivers/i2c/busses/i2c-gxp.c
--
2.17.1
^ permalink raw reply [flat|nested] 30+ messages in thread
* [PATCH v4 0/5] ARM: Add GXP I2C Support
@ 2023-01-25 18:44 ` nick.hawkins
0 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
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.
---
Changes since v3:
*Switch engine variable to u32
*Disable IRQ on device remove with register write instead
*Provided even greater description with the use of Phandle
Changes since v2:
*Disable IRQ on a 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 for u8 read
*Provided a better description of Phandle in yaml
Changes since v1:
*Removed yaml documentation of hpe,gxp-sysreg as it has been
applied to syscon.yaml
*Made i2cX a generic node name i2c in dts file
*Added status field to the dtsi and the dts for i2c bus
*Removed unnecessary size-cells and address-cells from yaml
*Removed phandle from hpe,sysreg-phandle
*Changed hpe,i2c-max-bus-freq to clock-frequency
*Removed rogue tab in structure definition
*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
*Removed informational prints from probe function
*Switched dev_err -> dev_err_probe in probe function
*Used the respective helper for mapping the resource to
__iomem
Nick Hawkins (5):
i2c: hpe: Add GXP SoC I2C Controller
dt-bindings: i2c: Add hpe,gxp-i2c
ARM: dts: hpe: Add I2C Topology
ARM: multi_v7_defconfig: add gxp i2c module
MAINTAINERS: Add HPE GXP I2C Support
.../devicetree/bindings/i2c/hpe,gxp-i2c.yaml | 59 ++
MAINTAINERS | 2 +
arch/arm/boot/dts/hpe-bmc-dl360gen10.dts | 109 ++++
arch/arm/boot/dts/hpe-gxp.dtsi | 125 ++++
arch/arm/configs/multi_v7_defconfig | 1 +
drivers/i2c/busses/Kconfig | 7 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-gxp.c | 603 ++++++++++++++++++
8 files changed, 907 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
create mode 100644 drivers/i2c/busses/i2c-gxp.c
--
2.17.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 30+ messages in thread
* [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller
2023-01-25 18:44 ` nick.hawkins
@ 2023-01-25 18:44 ` nick.hawkins
-1 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
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>
---
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 <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
+
+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 <nick.hawkins@hpe.com>");
+MODULE_DESCRIPTION("HPE GXP I2C bus driver");
+MODULE_LICENSE("GPL");
--
2.17.1
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller
@ 2023-01-25 18:44 ` nick.hawkins
0 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
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>
---
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 <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
+
+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 <nick.hawkins@hpe.com>");
+MODULE_DESCRIPTION("HPE GXP I2C bus driver");
+MODULE_LICENSE("GPL");
--
2.17.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c
2023-01-25 18:44 ` nick.hawkins
@ 2023-01-25 18:44 ` nick.hawkins
-1 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
Document compatibility string to support I2C controller
in GXP.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
---
v4:
*Provide even greater description with the use
of Phandle
*Reorder properties so they match the required
order
v3:
*Provide better description with use of Phandle
v2:
*Removed uneccessary size-cells and address-cells
*Removed phandle from hpe,sysreg-phandle
*Changed hpe,i2c-max-bus-freq to clock-frequency
---
.../devicetree/bindings/i2c/hpe,gxp-i2c.yaml | 59 +++++++++++++++++++
1 file changed, 59 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
diff --git a/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml b/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
new file mode 100644
index 000000000000..6604dcd47251
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/hpe,gxp-i2c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: HPE GXP SoC I2C Controller
+
+maintainers:
+ - Nick Hawkins <nick.hawkins@hpe.com>
+
+allOf:
+ - $ref: /schemas/i2c/i2c-controller.yaml#
+
+properties:
+ compatible:
+ const: hpe,gxp-i2c
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ clock-frequency:
+ default: 100000
+
+ hpe,sysreg:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description:
+ Phandle to the global status and enable interrupt registers shared
+ between each I2C engine controller instance. It enables the I2C
+ engine controller to act as both a master or slave by being able to
+ arm and respond to interrupts from its engine. Each bit in the
+ registers represent the respective bit position.
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ i2c@2600 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2500 0x70>;
+ interrupts = <9>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <10000>;
+
+ eeprom@50 {
+ compatible = "atmel,24c128";
+ reg = <0x50>;
+ };
+ };
--
2.17.1
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c
@ 2023-01-25 18:44 ` nick.hawkins
0 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
Document compatibility string to support I2C controller
in GXP.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
---
v4:
*Provide even greater description with the use
of Phandle
*Reorder properties so they match the required
order
v3:
*Provide better description with use of Phandle
v2:
*Removed uneccessary size-cells and address-cells
*Removed phandle from hpe,sysreg-phandle
*Changed hpe,i2c-max-bus-freq to clock-frequency
---
.../devicetree/bindings/i2c/hpe,gxp-i2c.yaml | 59 +++++++++++++++++++
1 file changed, 59 insertions(+)
create mode 100644 Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
diff --git a/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml b/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
new file mode 100644
index 000000000000..6604dcd47251
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/hpe,gxp-i2c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: HPE GXP SoC I2C Controller
+
+maintainers:
+ - Nick Hawkins <nick.hawkins@hpe.com>
+
+allOf:
+ - $ref: /schemas/i2c/i2c-controller.yaml#
+
+properties:
+ compatible:
+ const: hpe,gxp-i2c
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ clock-frequency:
+ default: 100000
+
+ hpe,sysreg:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description:
+ Phandle to the global status and enable interrupt registers shared
+ between each I2C engine controller instance. It enables the I2C
+ engine controller to act as both a master or slave by being able to
+ arm and respond to interrupts from its engine. Each bit in the
+ registers represent the respective bit position.
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ i2c@2600 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2500 0x70>;
+ interrupts = <9>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <10000>;
+
+ eeprom@50 {
+ compatible = "atmel,24c128";
+ reg = <0x50>;
+ };
+ };
--
2.17.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 3/5] ARM: dts: hpe: Add I2C Topology
2023-01-25 18:44 ` nick.hawkins
@ 2023-01-25 18:44 ` nick.hawkins
-1 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
Add 9 I2C Engines, 2 MUXs, and a EEPROM to the device tree.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
---
v4:
*No change
v3:
*No change
v2:
*Made i2cX a generic node name i2c in the dts
*Added status field to dtsi and dts for i2c bus
---
arch/arm/boot/dts/hpe-bmc-dl360gen10.dts | 109 ++++++++++++++++++++
arch/arm/boot/dts/hpe-gxp.dtsi | 125 +++++++++++++++++++++++
2 files changed, 234 insertions(+)
diff --git a/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts b/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
index 3a7382ce40ef..1f2547fe9ae3 100644
--- a/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
+++ b/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
@@ -23,4 +23,113 @@
device_type = "memory";
reg = <0x40000000 0x20000000>;
};
+
+ i2cmux@4 {
+ compatible = "i2c-mux-reg";
+ i2c-parent = <&i2c4>;
+ reg = <0xd1000074 0x1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@1 {
+ reg = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@4 {
+ reg = <4>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+ };
+
+ i2cmux@6 {
+ compatible = "i2c-mux-reg";
+ i2c-parent = <&i2c6>;
+ reg = <0xd1000076 0x1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@1 {
+ reg = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@2 {
+ reg = <2>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@4 {
+ reg = <4>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@5 {
+ reg = <5>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+ };
+};
+
+&i2c0 {
+ status = "okay";
+};
+
+&i2c1 {
+ status = "okay";
+};
+
+&i2c2 {
+ status = "okay";
+ eeprom@50 {
+ compatible = "atmel,24c02";
+ pagesize = <8>;
+ reg = <0x50>;
+ };
+};
+
+&i2c3 {
+ status = "okay";
+};
+
+&i2c4 {
+ status = "okay";
+};
+
+&i2c5 {
+ status = "okay";
+};
+
+&i2c6 {
+ status = "okay";
+};
+
+&i2c7 {
+ status = "okay";
+};
+
+&i2c8 {
+ status = "okay";
+};
+
+&i2c9 {
+ status = "okay";
};
diff --git a/arch/arm/boot/dts/hpe-gxp.dtsi b/arch/arm/boot/dts/hpe-gxp.dtsi
index cf735b3c4f35..3bc071149bae 100644
--- a/arch/arm/boot/dts/hpe-gxp.dtsi
+++ b/arch/arm/boot/dts/hpe-gxp.dtsi
@@ -122,6 +122,131 @@
interrupts = <6>;
interrupt-parent = <&vic0>;
};
+
+ sysreg_system_controller: syscon@f8 {
+ compatible = "hpe,gxp-sysreg", "syscon";
+ reg = <0xf8 0x8>;
+ };
+
+ i2c0: i2c@2000 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2000 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c1: i2c@2100 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2100 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c2: i2c@2200 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2200 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c3: i2c@2300 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2300 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c4: i2c@2400 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2400 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c5: i2c@2500 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2500 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c6: i2c@2600 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2600 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c7: i2c@2700 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2700 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c8: i2c@2800 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2800 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c9: i2c@2900 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2900 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
};
};
};
--
2.17.1
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 3/5] ARM: dts: hpe: Add I2C Topology
@ 2023-01-25 18:44 ` nick.hawkins
0 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
Add 9 I2C Engines, 2 MUXs, and a EEPROM to the device tree.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
---
v4:
*No change
v3:
*No change
v2:
*Made i2cX a generic node name i2c in the dts
*Added status field to dtsi and dts for i2c bus
---
arch/arm/boot/dts/hpe-bmc-dl360gen10.dts | 109 ++++++++++++++++++++
arch/arm/boot/dts/hpe-gxp.dtsi | 125 +++++++++++++++++++++++
2 files changed, 234 insertions(+)
diff --git a/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts b/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
index 3a7382ce40ef..1f2547fe9ae3 100644
--- a/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
+++ b/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
@@ -23,4 +23,113 @@
device_type = "memory";
reg = <0x40000000 0x20000000>;
};
+
+ i2cmux@4 {
+ compatible = "i2c-mux-reg";
+ i2c-parent = <&i2c4>;
+ reg = <0xd1000074 0x1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@1 {
+ reg = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@4 {
+ reg = <4>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+ };
+
+ i2cmux@6 {
+ compatible = "i2c-mux-reg";
+ i2c-parent = <&i2c6>;
+ reg = <0xd1000076 0x1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c@1 {
+ reg = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@2 {
+ reg = <2>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@3 {
+ reg = <3>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@4 {
+ reg = <4>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+
+ i2c@5 {
+ reg = <5>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ };
+ };
+};
+
+&i2c0 {
+ status = "okay";
+};
+
+&i2c1 {
+ status = "okay";
+};
+
+&i2c2 {
+ status = "okay";
+ eeprom@50 {
+ compatible = "atmel,24c02";
+ pagesize = <8>;
+ reg = <0x50>;
+ };
+};
+
+&i2c3 {
+ status = "okay";
+};
+
+&i2c4 {
+ status = "okay";
+};
+
+&i2c5 {
+ status = "okay";
+};
+
+&i2c6 {
+ status = "okay";
+};
+
+&i2c7 {
+ status = "okay";
+};
+
+&i2c8 {
+ status = "okay";
+};
+
+&i2c9 {
+ status = "okay";
};
diff --git a/arch/arm/boot/dts/hpe-gxp.dtsi b/arch/arm/boot/dts/hpe-gxp.dtsi
index cf735b3c4f35..3bc071149bae 100644
--- a/arch/arm/boot/dts/hpe-gxp.dtsi
+++ b/arch/arm/boot/dts/hpe-gxp.dtsi
@@ -122,6 +122,131 @@
interrupts = <6>;
interrupt-parent = <&vic0>;
};
+
+ sysreg_system_controller: syscon@f8 {
+ compatible = "hpe,gxp-sysreg", "syscon";
+ reg = <0xf8 0x8>;
+ };
+
+ i2c0: i2c@2000 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2000 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c1: i2c@2100 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2100 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c2: i2c@2200 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2200 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c3: i2c@2300 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2300 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c4: i2c@2400 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2400 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c5: i2c@2500 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2500 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c6: i2c@2600 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2600 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c7: i2c@2700 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2700 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c8: i2c@2800 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2800 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
+
+ i2c9: i2c@2900 {
+ compatible = "hpe,gxp-i2c";
+ reg = <0x2900 0x70>;
+ interrupts = <9>;
+ interrupt-parent = <&vic0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ status = "disabled";
+ hpe,sysreg = <&sysreg_system_controller>;
+ clock-frequency = <100000>;
+ };
};
};
};
--
2.17.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 4/5] ARM: multi_v7_defconfig: add gxp i2c module
2023-01-25 18:44 ` nick.hawkins
@ 2023-01-25 18:44 ` nick.hawkins
-1 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
Add the CONFIG_I2C_GXP symbol to enable the GXP SoC I2C capabilities.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
---
v4:
*No change
v3:
*No change
v2:
*No change
---
arch/arm/configs/multi_v7_defconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
index b61b2e3d116b..8a19b1dc10d0 100644
--- a/arch/arm/configs/multi_v7_defconfig
+++ b/arch/arm/configs/multi_v7_defconfig
@@ -411,6 +411,7 @@ CONFIG_I2C_DAVINCI=y
CONFIG_I2C_DESIGNWARE_PLATFORM=y
CONFIG_I2C_DIGICOLOR=m
CONFIG_I2C_EMEV2=m
+CONFIG_I2C_GXP=m
CONFIG_I2C_IMX=y
CONFIG_I2C_MESON=y
CONFIG_I2C_MV64XXX=y
--
2.17.1
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 4/5] ARM: multi_v7_defconfig: add gxp i2c module
@ 2023-01-25 18:44 ` nick.hawkins
0 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
Add the CONFIG_I2C_GXP symbol to enable the GXP SoC I2C capabilities.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
---
v4:
*No change
v3:
*No change
v2:
*No change
---
arch/arm/configs/multi_v7_defconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
index b61b2e3d116b..8a19b1dc10d0 100644
--- a/arch/arm/configs/multi_v7_defconfig
+++ b/arch/arm/configs/multi_v7_defconfig
@@ -411,6 +411,7 @@ CONFIG_I2C_DAVINCI=y
CONFIG_I2C_DESIGNWARE_PLATFORM=y
CONFIG_I2C_DIGICOLOR=m
CONFIG_I2C_EMEV2=m
+CONFIG_I2C_GXP=m
CONFIG_I2C_IMX=y
CONFIG_I2C_MESON=y
CONFIG_I2C_MV64XXX=y
--
2.17.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support
2023-01-25 18:44 ` nick.hawkins
@ 2023-01-25 18:44 ` nick.hawkins
-1 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
Add the I2C controller source and bindings.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
---
v4:
*No change
v3:
*No change
v2:
*No change
---
MAINTAINERS | 2 ++
1 file changed, 2 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 1daadaa4d48b..d671a8b6968e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2217,12 +2217,14 @@ M: Jean-Marie Verdun <verdun@hpe.com>
M: Nick Hawkins <nick.hawkins@hpe.com>
S: Maintained
F: Documentation/devicetree/bindings/arm/hpe,gxp.yaml
+F: Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
F: Documentation/devicetree/bindings/spi/hpe,gxp-spifi.yaml
F: Documentation/devicetree/bindings/timer/hpe,gxp-timer.yaml
F: arch/arm/boot/dts/hpe-bmc*
F: arch/arm/boot/dts/hpe-gxp*
F: arch/arm/mach-hpe/
F: drivers/clocksource/timer-gxp.c
+F: drivers/i2c/busses/i2c-gxp.c
F: drivers/spi/spi-gxp.c
F: drivers/watchdog/gxp-wdt.c
--
2.17.1
^ permalink raw reply related [flat|nested] 30+ messages in thread
* [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support
@ 2023-01-25 18:44 ` nick.hawkins
0 siblings, 0 replies; 30+ messages in thread
From: nick.hawkins @ 2023-01-25 18:44 UTC (permalink / raw)
To: verdun, nick.hawkins, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
From: Nick Hawkins <nick.hawkins@hpe.com>
Add the I2C controller source and bindings.
Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
---
v4:
*No change
v3:
*No change
v2:
*No change
---
MAINTAINERS | 2 ++
1 file changed, 2 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 1daadaa4d48b..d671a8b6968e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2217,12 +2217,14 @@ M: Jean-Marie Verdun <verdun@hpe.com>
M: Nick Hawkins <nick.hawkins@hpe.com>
S: Maintained
F: Documentation/devicetree/bindings/arm/hpe,gxp.yaml
+F: Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
F: Documentation/devicetree/bindings/spi/hpe,gxp-spifi.yaml
F: Documentation/devicetree/bindings/timer/hpe,gxp-timer.yaml
F: arch/arm/boot/dts/hpe-bmc*
F: arch/arm/boot/dts/hpe-gxp*
F: arch/arm/mach-hpe/
F: drivers/clocksource/timer-gxp.c
+F: drivers/i2c/busses/i2c-gxp.c
F: drivers/spi/spi-gxp.c
F: drivers/watchdog/gxp-wdt.c
--
2.17.1
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply related [flat|nested] 30+ messages in thread
* Re: [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c
2023-01-25 18:44 ` nick.hawkins
@ 2023-01-25 21:18 ` Rob Herring
-1 siblings, 0 replies; 30+ messages in thread
From: Rob Herring @ 2023-01-25 21:18 UTC (permalink / raw)
To: nick.hawkins
Cc: verdun, krzysztof.kozlowski+dt, linux, linux-i2c, devicetree,
linux-kernel, linux-arm-kernel, joel
On Wed, Jan 25, 2023 at 12:44:35PM -0600, nick.hawkins@hpe.com wrote:
> From: Nick Hawkins <nick.hawkins@hpe.com>
>
> Document compatibility string to support I2C controller
> in GXP.
>
> Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
>
> ---
> v4:
> *Provide even greater description with the use
> of Phandle
> *Reorder properties so they match the required
> order
> v3:
> *Provide better description with use of Phandle
> v2:
> *Removed uneccessary size-cells and address-cells
> *Removed phandle from hpe,sysreg-phandle
> *Changed hpe,i2c-max-bus-freq to clock-frequency
> ---
> .../devicetree/bindings/i2c/hpe,gxp-i2c.yaml | 59 +++++++++++++++++++
> 1 file changed, 59 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
>
> diff --git a/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml b/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
> new file mode 100644
> index 000000000000..6604dcd47251
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
> @@ -0,0 +1,59 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/i2c/hpe,gxp-i2c.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: HPE GXP SoC I2C Controller
> +
> +maintainers:
> + - Nick Hawkins <nick.hawkins@hpe.com>
> +
> +allOf:
> + - $ref: /schemas/i2c/i2c-controller.yaml#
> +
> +properties:
> + compatible:
> + const: hpe,gxp-i2c
> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + clock-frequency:
> + default: 100000
> +
> + hpe,sysreg:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description:
> + Phandle to the global status and enable interrupt registers shared
> + between each I2C engine controller instance. It enables the I2C
> + engine controller to act as both a master or slave by being able to
> + arm and respond to interrupts from its engine. Each bit in the
> + registers represent the respective bit position.
Each bit represents the bit position?
AIUI, each I2C instance has a bit in it needs to control. How does the
driver know what instance (and therefore the correct bit)? Typically you
would have a 2nd cell here with that information.
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> + i2c@2600 {
> + compatible = "hpe,gxp-i2c";
> + reg = <0x2500 0x70>;
> + interrupts = <9>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + hpe,sysreg = <&sysreg_system_controller>;
> + clock-frequency = <10000>;
> +
> + eeprom@50 {
> + compatible = "atmel,24c128";
> + reg = <0x50>;
> + };
> + };
> --
> 2.17.1
>
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c
@ 2023-01-25 21:18 ` Rob Herring
0 siblings, 0 replies; 30+ messages in thread
From: Rob Herring @ 2023-01-25 21:18 UTC (permalink / raw)
To: nick.hawkins
Cc: verdun, krzysztof.kozlowski+dt, linux, linux-i2c, devicetree,
linux-kernel, linux-arm-kernel, joel
On Wed, Jan 25, 2023 at 12:44:35PM -0600, nick.hawkins@hpe.com wrote:
> From: Nick Hawkins <nick.hawkins@hpe.com>
>
> Document compatibility string to support I2C controller
> in GXP.
>
> Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
>
> ---
> v4:
> *Provide even greater description with the use
> of Phandle
> *Reorder properties so they match the required
> order
> v3:
> *Provide better description with use of Phandle
> v2:
> *Removed uneccessary size-cells and address-cells
> *Removed phandle from hpe,sysreg-phandle
> *Changed hpe,i2c-max-bus-freq to clock-frequency
> ---
> .../devicetree/bindings/i2c/hpe,gxp-i2c.yaml | 59 +++++++++++++++++++
> 1 file changed, 59 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
>
> diff --git a/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml b/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
> new file mode 100644
> index 000000000000..6604dcd47251
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/hpe,gxp-i2c.yaml
> @@ -0,0 +1,59 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/i2c/hpe,gxp-i2c.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: HPE GXP SoC I2C Controller
> +
> +maintainers:
> + - Nick Hawkins <nick.hawkins@hpe.com>
> +
> +allOf:
> + - $ref: /schemas/i2c/i2c-controller.yaml#
> +
> +properties:
> + compatible:
> + const: hpe,gxp-i2c
> +
> + reg:
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + clock-frequency:
> + default: 100000
> +
> + hpe,sysreg:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description:
> + Phandle to the global status and enable interrupt registers shared
> + between each I2C engine controller instance. It enables the I2C
> + engine controller to act as both a master or slave by being able to
> + arm and respond to interrupts from its engine. Each bit in the
> + registers represent the respective bit position.
Each bit represents the bit position?
AIUI, each I2C instance has a bit in it needs to control. How does the
driver know what instance (and therefore the correct bit)? Typically you
would have a 2nd cell here with that information.
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> + i2c@2600 {
> + compatible = "hpe,gxp-i2c";
> + reg = <0x2500 0x70>;
> + interrupts = <9>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + hpe,sysreg = <&sysreg_system_controller>;
> + clock-frequency = <10000>;
> +
> + eeprom@50 {
> + compatible = "atmel,24c128";
> + reg = <0x50>;
> + };
> + };
> --
> 2.17.1
>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c
2023-01-25 21:18 ` Rob Herring
@ 2023-01-25 21:31 ` Hawkins, Nick
-1 siblings, 0 replies; 30+ messages in thread
From: Hawkins, Nick @ 2023-01-25 21:31 UTC (permalink / raw)
To: Rob Herring
Cc: Verdun, Jean-Marie, krzysztof.kozlowski+dt, linux, linux-i2c,
devicetree, linux-kernel, linux-arm-kernel, joel
> > + hpe,sysreg:
> > + $ref: /schemas/types.yaml#/definitions/phandle
> > + description:
> > + Phandle to the global status and enable interrupt registers shared
> > + between each I2C engine controller instance. It enables the I2C
> > + engine controller to act as both a master or slave by being able to
> > + arm and respond to interrupts from its engine. Each bit in the
> > + registers represent the respective bit position.
> Each bit represents the bit position?
Yes what I mean here is that bit 0 represents engine 0, bit 1 represents
engine 1 and so on. I will reword this how you have below.
> AIUI, each I2C instance has a bit in it needs to control. How does the
> driver know what instance (and therefore the correct bit)? Typically you
> would have a 2nd cell here with that information.
We are currently using the memory area designated reg to determine
which engine we are on.
Here is a snippet from patch 1 of this patchset that introduces the driver:
/* Use physical memory address to determine which I2C engine this is. */
+ drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
This works because each engine is 0x100 apart.
I would however like to conform to a standard to designate the engine.
Is there an existing property I can leverage?
Thanks for your feedback,
-Nick Hawkins
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c
@ 2023-01-25 21:31 ` Hawkins, Nick
0 siblings, 0 replies; 30+ messages in thread
From: Hawkins, Nick @ 2023-01-25 21:31 UTC (permalink / raw)
To: Rob Herring
Cc: Verdun, Jean-Marie, krzysztof.kozlowski+dt, linux, linux-i2c,
devicetree, linux-kernel, linux-arm-kernel, joel
> > + hpe,sysreg:
> > + $ref: /schemas/types.yaml#/definitions/phandle
> > + description:
> > + Phandle to the global status and enable interrupt registers shared
> > + between each I2C engine controller instance. It enables the I2C
> > + engine controller to act as both a master or slave by being able to
> > + arm and respond to interrupts from its engine. Each bit in the
> > + registers represent the respective bit position.
> Each bit represents the bit position?
Yes what I mean here is that bit 0 represents engine 0, bit 1 represents
engine 1 and so on. I will reword this how you have below.
> AIUI, each I2C instance has a bit in it needs to control. How does the
> driver know what instance (and therefore the correct bit)? Typically you
> would have a 2nd cell here with that information.
We are currently using the memory area designated reg to determine
which engine we are on.
Here is a snippet from patch 1 of this patchset that introduces the driver:
/* Use physical memory address to determine which I2C engine this is. */
+ drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
This works because each engine is 0x100 apart.
I would however like to conform to a standard to designate the engine.
Is there an existing property I can leverage?
Thanks for your feedback,
-Nick Hawkins
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c
2023-01-25 21:31 ` Hawkins, Nick
@ 2023-01-26 13:38 ` Rob Herring
-1 siblings, 0 replies; 30+ messages in thread
From: Rob Herring @ 2023-01-26 13:38 UTC (permalink / raw)
To: Hawkins, Nick
Cc: Verdun, Jean-Marie, krzysztof.kozlowski+dt, linux, linux-i2c,
devicetree, linux-kernel, linux-arm-kernel, joel
On Wed, Jan 25, 2023 at 3:32 PM Hawkins, Nick <nick.hawkins@hpe.com> wrote:
>
> > > + hpe,sysreg:
> > > + $ref: /schemas/types.yaml#/definitions/phandle
> > > + description:
> > > + Phandle to the global status and enable interrupt registers shared
> > > + between each I2C engine controller instance. It enables the I2C
> > > + engine controller to act as both a master or slave by being able to
> > > + arm and respond to interrupts from its engine. Each bit in the
> > > + registers represent the respective bit position.
>
>
> > Each bit represents the bit position?
>
> Yes what I mean here is that bit 0 represents engine 0, bit 1 represents
> engine 1 and so on. I will reword this how you have below.
>
> > AIUI, each I2C instance has a bit in it needs to control. How does the
> > driver know what instance (and therefore the correct bit)? Typically you
> > would have a 2nd cell here with that information.
>
> We are currently using the memory area designated reg to determine
> which engine we are on.
>
> Here is a snippet from patch 1 of this patchset that introduces the driver:
> /* Use physical memory address to determine which I2C engine this is. */
> + drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
>
> This works because each engine is 0x100 apart.
Ah, that works fine then.
Reviewed-by: Rob Herring <robh@kernel.org>
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c
@ 2023-01-26 13:38 ` Rob Herring
0 siblings, 0 replies; 30+ messages in thread
From: Rob Herring @ 2023-01-26 13:38 UTC (permalink / raw)
To: Hawkins, Nick
Cc: Verdun, Jean-Marie, krzysztof.kozlowski+dt, linux, linux-i2c,
devicetree, linux-kernel, linux-arm-kernel, joel
On Wed, Jan 25, 2023 at 3:32 PM Hawkins, Nick <nick.hawkins@hpe.com> wrote:
>
> > > + hpe,sysreg:
> > > + $ref: /schemas/types.yaml#/definitions/phandle
> > > + description:
> > > + Phandle to the global status and enable interrupt registers shared
> > > + between each I2C engine controller instance. It enables the I2C
> > > + engine controller to act as both a master or slave by being able to
> > > + arm and respond to interrupts from its engine. Each bit in the
> > > + registers represent the respective bit position.
>
>
> > Each bit represents the bit position?
>
> Yes what I mean here is that bit 0 represents engine 0, bit 1 represents
> engine 1 and so on. I will reword this how you have below.
>
> > AIUI, each I2C instance has a bit in it needs to control. How does the
> > driver know what instance (and therefore the correct bit)? Typically you
> > would have a 2nd cell here with that information.
>
> We are currently using the memory area designated reg to determine
> which engine we are on.
>
> Here is a snippet from patch 1 of this patchset that introduces the driver:
> /* Use physical memory address to determine which I2C engine this is. */
> + drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
>
> This works because each engine is 0x100 apart.
Ah, that works fine then.
Reviewed-by: Rob Herring <robh@kernel.org>
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support
2023-01-25 18:44 ` nick.hawkins
@ 2023-01-28 18:38 ` Wolfram Sang
-1 siblings, 0 replies; 30+ messages in thread
From: Wolfram Sang @ 2023-01-28 18:38 UTC (permalink / raw)
To: nick.hawkins
Cc: verdun, robh+dt, krzysztof.kozlowski+dt, linux, linux-i2c,
devicetree, linux-kernel, linux-arm-kernel, joel
[-- Attachment #1: Type: text/plain, Size: 448 bytes --]
On Wed, Jan 25, 2023 at 12:44:38PM -0600, nick.hawkins@hpe.com wrote:
> From: Nick Hawkins <nick.hawkins@hpe.com>
>
> Add the I2C controller source and bindings.
>
> Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
I assume this better goes via the arm-soc-tree as well to reduce merge
conflicts, so:
Acked-by: Wolfram Sang <wsa@kernel.org>
Let me know if I should pick this instead. Will review the driver in the
next days.
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^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support
@ 2023-01-28 18:38 ` Wolfram Sang
0 siblings, 0 replies; 30+ messages in thread
From: Wolfram Sang @ 2023-01-28 18:38 UTC (permalink / raw)
To: nick.hawkins
Cc: verdun, robh+dt, krzysztof.kozlowski+dt, linux, linux-i2c,
devicetree, linux-kernel, linux-arm-kernel, joel
[-- Attachment #1.1: Type: text/plain, Size: 448 bytes --]
On Wed, Jan 25, 2023 at 12:44:38PM -0600, nick.hawkins@hpe.com wrote:
> From: Nick Hawkins <nick.hawkins@hpe.com>
>
> Add the I2C controller source and bindings.
>
> Signed-off-by: Nick Hawkins <nick.hawkins@hpe.com>
I assume this better goes via the arm-soc-tree as well to reduce merge
conflicts, so:
Acked-by: Wolfram Sang <wsa@kernel.org>
Let me know if I should pick this instead. Will review the driver in the
next days.
[-- Attachment #1.2: signature.asc --]
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_______________________________________________
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linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support
2023-01-28 18:38 ` Wolfram Sang
@ 2023-02-07 21:53 ` Hawkins, Nick
-1 siblings, 0 replies; 30+ messages in thread
From: Hawkins, Nick @ 2023-02-07 21:53 UTC (permalink / raw)
To: Wolfram Sang
Cc: Verdun, Jean-Marie, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
> Let me know if I should pick this instead. Will review the driver in the
> next days.
Please include it. There may be warnings generated if MAINTAINERS
does not list the files at the time of your commit.
Thank you,
-Nick Hawkins
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support
@ 2023-02-07 21:53 ` Hawkins, Nick
0 siblings, 0 replies; 30+ messages in thread
From: Hawkins, Nick @ 2023-02-07 21:53 UTC (permalink / raw)
To: Wolfram Sang
Cc: Verdun, Jean-Marie, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
> Let me know if I should pick this instead. Will review the driver in the
> next days.
Please include it. There may be warnings generated if MAINTAINERS
does not list the files at the time of your commit.
Thank you,
-Nick Hawkins
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 30+ messages in thread
* RE: [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support
2023-02-07 21:53 ` Hawkins, Nick
@ 2023-02-15 19:26 ` Hawkins, Nick
-1 siblings, 0 replies; 30+ messages in thread
From: Hawkins, Nick @ 2023-02-15 19:26 UTC (permalink / raw)
To: Wolfram Sang
Cc: Verdun, Jean-Marie, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
> > Let me know if I should pick this instead. Will review the driver in the
> > next days.
> Please include it. There may be warnings generated if MAINTAINERS
does not list the files at the time of your commit.
> Thank you,
> -Nick Hawkins
Greetings Wolfram,
Just a gentle reminder on this review.
Thank you for your time,
-Nick Hawkins
^ permalink raw reply [flat|nested] 30+ messages in thread
* RE: [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support
@ 2023-02-15 19:26 ` Hawkins, Nick
0 siblings, 0 replies; 30+ messages in thread
From: Hawkins, Nick @ 2023-02-15 19:26 UTC (permalink / raw)
To: Wolfram Sang
Cc: Verdun, Jean-Marie, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
> > Let me know if I should pick this instead. Will review the driver in the
> > next days.
> Please include it. There may be warnings generated if MAINTAINERS
does not list the files at the time of your commit.
> Thank you,
> -Nick Hawkins
Greetings Wolfram,
Just a gentle reminder on this review.
Thank you for your time,
-Nick Hawkins
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller
2023-01-25 18:44 ` nick.hawkins
@ 2023-02-15 20:29 ` Wolfram Sang
-1 siblings, 0 replies; 30+ messages in thread
From: Wolfram Sang @ 2023-02-15 20:29 UTC (permalink / raw)
To: nick.hawkins
Cc: verdun, robh+dt, krzysztof.kozlowski+dt, linux, linux-i2c,
devicetree, linux-kernel, linux-arm-kernel, joel
[-- Attachment #1: Type: text/plain, Size: 7270 bytes --]
Hi Nick,
> 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.
> +
Shouldn't this be in the "I2C system bus drivers (mostly embedded /
system-on-chip)" section? (alphabetically sorted)
> +static bool i2c_global_init_done;
Can't we avoid this static by checking if i2cg_map is NULL/non-NULL?
> +
> +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;
> + }
I'd write it more concise as:
value |= drvdata->curr_msg->flags & I2C_M_RD ? 0x05 : 0x01;
But this is a matter of taste.
> +
> + 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);
Please don't write error message to the log on timeouts. They can
happen. Think of an EEPROM which is busy because it needs to erase a
page. Upper layers need to handle this correctly, the user doesn't need
to know about it.
> + 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;
Same here for NACK. Otherwise i2cdetect will flood your logfile.
> + }
> +
> + 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);
Does it make sense to have #defines for the magic values for I2CSCMD?
BTW, is the datasheet public?
...
> +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);
Also here, lots of magic values. Can we do something about it?
> +}
> +
> +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;
This breaks on my 64-bit test-build, so it will also fail with
COMPILE_TEST.
drivers/i2c/busses/i2c-gxp.c: In function ‘gxp_i2c_probe’:
drivers/i2c/busses/i2c-gxp.c:533:28: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
533 | drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
The rest looks good to me.
Except for removing the hardcoded values, the other fixes should be
fairly simple, I think. So, hardcoded values could be changed
incrementally maybe. If this is possible at all. I still plan to have
this driver in 6.3.
Happy hacking,
Wolfram
[-- Attachment #2: signature.asc --]
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^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller
@ 2023-02-15 20:29 ` Wolfram Sang
0 siblings, 0 replies; 30+ messages in thread
From: Wolfram Sang @ 2023-02-15 20:29 UTC (permalink / raw)
To: nick.hawkins
Cc: verdun, robh+dt, krzysztof.kozlowski+dt, linux, linux-i2c,
devicetree, linux-kernel, linux-arm-kernel, joel
[-- Attachment #1.1: Type: text/plain, Size: 7270 bytes --]
Hi Nick,
> 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.
> +
Shouldn't this be in the "I2C system bus drivers (mostly embedded /
system-on-chip)" section? (alphabetically sorted)
> +static bool i2c_global_init_done;
Can't we avoid this static by checking if i2cg_map is NULL/non-NULL?
> +
> +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;
> + }
I'd write it more concise as:
value |= drvdata->curr_msg->flags & I2C_M_RD ? 0x05 : 0x01;
But this is a matter of taste.
> +
> + 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);
Please don't write error message to the log on timeouts. They can
happen. Think of an EEPROM which is busy because it needs to erase a
page. Upper layers need to handle this correctly, the user doesn't need
to know about it.
> + 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;
Same here for NACK. Otherwise i2cdetect will flood your logfile.
> + }
> +
> + 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);
Does it make sense to have #defines for the magic values for I2CSCMD?
BTW, is the datasheet public?
...
> +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);
Also here, lots of magic values. Can we do something about it?
> +}
> +
> +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;
This breaks on my 64-bit test-build, so it will also fail with
COMPILE_TEST.
drivers/i2c/busses/i2c-gxp.c: In function ‘gxp_i2c_probe’:
drivers/i2c/busses/i2c-gxp.c:533:28: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
533 | drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
The rest looks good to me.
Except for removing the hardcoded values, the other fixes should be
fairly simple, I think. So, hardcoded values could be changed
incrementally maybe. If this is possible at all. I still plan to have
this driver in 6.3.
Happy hacking,
Wolfram
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^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller
2023-02-15 20:29 ` Wolfram Sang
@ 2023-02-16 20:02 ` Hawkins, Nick
-1 siblings, 0 replies; 30+ messages in thread
From: Hawkins, Nick @ 2023-02-16 20:02 UTC (permalink / raw)
To: Wolfram Sang
Cc: Verdun, Jean-Marie, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
> Does it make sense to have #defines for the magic values for I2CSCMD?
> BTW, is the datasheet public?
I will work on the defines and get rid of all the magic values.
Unfortunately, there is no public spec available currently.
Hopefully, we will have one someday though.
> > + /* Use physical memory address to determine which I2C engine this is. */
> > + drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
> This breaks on my 64-bit test-build, so it will also fail with
> COMPILE_TEST.
> drivers/i2c/busses/i2c-gxp.c: In function ‘gxp_i2c_probe’:
> drivers/i2c/busses/i2c-gxp.c:533:28: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
> 533 | drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
I am currently unable to reproduce this error. I even set W=2.
Would replacing (u32) with (unsigned long) resolve it?
Thanks,
-Nick Hawkins
^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller
@ 2023-02-16 20:02 ` Hawkins, Nick
0 siblings, 0 replies; 30+ messages in thread
From: Hawkins, Nick @ 2023-02-16 20:02 UTC (permalink / raw)
To: Wolfram Sang
Cc: Verdun, Jean-Marie, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
> Does it make sense to have #defines for the magic values for I2CSCMD?
> BTW, is the datasheet public?
I will work on the defines and get rid of all the magic values.
Unfortunately, there is no public spec available currently.
Hopefully, we will have one someday though.
> > + /* Use physical memory address to determine which I2C engine this is. */
> > + drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
> This breaks on my 64-bit test-build, so it will also fail with
> COMPILE_TEST.
> drivers/i2c/busses/i2c-gxp.c: In function ‘gxp_i2c_probe’:
> drivers/i2c/busses/i2c-gxp.c:533:28: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
> 533 | drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
I am currently unable to reproduce this error. I even set W=2.
Would replacing (u32) with (unsigned long) resolve it?
Thanks,
-Nick Hawkins
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linux-arm-kernel@lists.infradead.org
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^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller
2023-02-16 20:02 ` Hawkins, Nick
@ 2023-02-16 20:47 ` Wolfram Sang
-1 siblings, 0 replies; 30+ messages in thread
From: Wolfram Sang @ 2023-02-16 20:47 UTC (permalink / raw)
To: Hawkins, Nick
Cc: Verdun, Jean-Marie, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
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Hi Nick,
> I will work on the defines and get rid of all the magic values.
Cool, thank you!
> Unfortunately, there is no public spec available currently.
> Hopefully, we will have one someday though.
Then, the #defines are even more helpful!
> > drivers/i2c/busses/i2c-gxp.c: In function ‘gxp_i2c_probe’:
> > drivers/i2c/busses/i2c-gxp.c:533:28: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
> > 533 | drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
>
> I am currently unable to reproduce this error. I even set W=2.
Interesting. I have this version:
gcc (Debian 10.2.1-6) 10.2.1 20210110
> Would replacing (u32) with (unsigned long) resolve it?
Or size_t.
Happy hacking,
Wolfram
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^ permalink raw reply [flat|nested] 30+ messages in thread
* Re: [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller
@ 2023-02-16 20:47 ` Wolfram Sang
0 siblings, 0 replies; 30+ messages in thread
From: Wolfram Sang @ 2023-02-16 20:47 UTC (permalink / raw)
To: Hawkins, Nick
Cc: Verdun, Jean-Marie, robh+dt, krzysztof.kozlowski+dt, linux,
linux-i2c, devicetree, linux-kernel, linux-arm-kernel, joel
[-- Attachment #1.1: Type: text/plain, Size: 770 bytes --]
Hi Nick,
> I will work on the defines and get rid of all the magic values.
Cool, thank you!
> Unfortunately, there is no public spec available currently.
> Hopefully, we will have one someday though.
Then, the #defines are even more helpful!
> > drivers/i2c/busses/i2c-gxp.c: In function ‘gxp_i2c_probe’:
> > drivers/i2c/busses/i2c-gxp.c:533:28: error: cast from pointer to integer of different size [-Werror=pointer-to-int-cast]
> > 533 | drvdata->engine = ((u32)drvdata->base & 0xf00) >> 8;
>
> I am currently unable to reproduce this error. I even set W=2.
Interesting. I have this version:
gcc (Debian 10.2.1-6) 10.2.1 20210110
> Would replacing (u32) with (unsigned long) resolve it?
Or size_t.
Happy hacking,
Wolfram
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^ permalink raw reply [flat|nested] 30+ messages in thread
end of thread, other threads:[~2023-02-16 20:48 UTC | newest]
Thread overview: 30+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-01-25 18:44 [PATCH v4 0/5] ARM: Add GXP I2C Support nick.hawkins
2023-01-25 18:44 ` nick.hawkins
2023-01-25 18:44 ` [PATCH v4 1/5] i2c: hpe: Add GXP SoC I2C Controller nick.hawkins
2023-01-25 18:44 ` nick.hawkins
2023-02-15 20:29 ` Wolfram Sang
2023-02-15 20:29 ` Wolfram Sang
2023-02-16 20:02 ` Hawkins, Nick
2023-02-16 20:02 ` Hawkins, Nick
2023-02-16 20:47 ` Wolfram Sang
2023-02-16 20:47 ` Wolfram Sang
2023-01-25 18:44 ` [PATCH v4 2/5] dt-bindings: i2c: Add hpe,gxp-i2c nick.hawkins
2023-01-25 18:44 ` nick.hawkins
2023-01-25 21:18 ` Rob Herring
2023-01-25 21:18 ` Rob Herring
2023-01-25 21:31 ` Hawkins, Nick
2023-01-25 21:31 ` Hawkins, Nick
2023-01-26 13:38 ` Rob Herring
2023-01-26 13:38 ` Rob Herring
2023-01-25 18:44 ` [PATCH v4 3/5] ARM: dts: hpe: Add I2C Topology nick.hawkins
2023-01-25 18:44 ` nick.hawkins
2023-01-25 18:44 ` [PATCH v4 4/5] ARM: multi_v7_defconfig: add gxp i2c module nick.hawkins
2023-01-25 18:44 ` nick.hawkins
2023-01-25 18:44 ` [PATCH v4 5/5] MAINTAINERS: Add HPE GXP I2C Support nick.hawkins
2023-01-25 18:44 ` nick.hawkins
2023-01-28 18:38 ` Wolfram Sang
2023-01-28 18:38 ` Wolfram Sang
2023-02-07 21:53 ` Hawkins, Nick
2023-02-07 21:53 ` Hawkins, Nick
2023-02-15 19:26 ` Hawkins, Nick
2023-02-15 19:26 ` Hawkins, Nick
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