diff mbox series

[14/14] fsi: Add I2C Responder SCOM driver

Message ID 20230612195657.245125-15-eajames@linux.ibm.com
State Accepted
Commit c0b34bed0bbf7a058dab52d45e9aeb92bbe4c637
Headers show
Series fsi: Miscellaneous fixes and I2C Responder driver | expand

Commit Message

Eddie James June 12, 2023, 7:56 p.m. UTC
The I2CR has the capability to directly perform SCOM operations,
circumventing the need to drive the FSI2PIB engine. Add a new
driver to perform SCOM operations through the I2CR.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
---
 drivers/fsi/Kconfig     |   8 +++
 drivers/fsi/Makefile    |   1 +
 drivers/fsi/i2cr-scom.c | 154 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 163 insertions(+)
 create mode 100644 drivers/fsi/i2cr-scom.c

Comments

Rob Herring (Arm) Aug. 17, 2023, 3:56 p.m. UTC | #1
On Mon, Jun 12, 2023 at 02:56:57PM -0500, Eddie James wrote:
> The I2CR has the capability to directly perform SCOM operations,
> circumventing the need to drive the FSI2PIB engine. Add a new
> driver to perform SCOM operations through the I2CR.
> 
> Signed-off-by: Eddie James <eajames@linux.ibm.com>
> ---
>  drivers/fsi/Kconfig     |   8 +++
>  drivers/fsi/Makefile    |   1 +
>  drivers/fsi/i2cr-scom.c | 154 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 163 insertions(+)
>  create mode 100644 drivers/fsi/i2cr-scom.c
> 
> diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig
> index 999be82720c5..79a31593618a 100644
> --- a/drivers/fsi/Kconfig
> +++ b/drivers/fsi/Kconfig
> @@ -94,4 +94,12 @@ config FSI_OCC
>  	provide the raw sensor data as well as perform thermal and power
>  	management on the system.
>  
> +config I2CR_SCOM
> +	tristate "IBM I2C Responder SCOM driver"
> +	depends on FSI_MASTER_I2CR
> +	help
> +	  This option enables an I2C Responder based SCOM device driver. The
> +	  I2CR has the capability to directly perform SCOM operations instead
> +	  of using the FSI2PIB engine.
> +
>  endif
> diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile
> index 34dbaa1c452e..5550aa15e0b1 100644
> --- a/drivers/fsi/Makefile
> +++ b/drivers/fsi/Makefile
> @@ -9,3 +9,4 @@ obj-$(CONFIG_FSI_MASTER_AST_CF) += fsi-master-ast-cf.o
>  obj-$(CONFIG_FSI_SCOM) += fsi-scom.o
>  obj-$(CONFIG_FSI_SBEFIFO) += fsi-sbefifo.o
>  obj-$(CONFIG_FSI_OCC) += fsi-occ.o
> +obj-$(CONFIG_I2CR_SCOM) += i2cr-scom.o
> diff --git a/drivers/fsi/i2cr-scom.c b/drivers/fsi/i2cr-scom.c
> new file mode 100644
> index 000000000000..cb7e02213032
> --- /dev/null
> +++ b/drivers/fsi/i2cr-scom.c
> @@ -0,0 +1,154 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (C) IBM Corporation 2023 */
> +
> +#include <linux/cdev.h>
> +#include <linux/device.h>
> +#include <linux/fs.h>
> +#include <linux/fsi.h>
> +#include <linux/module.h>
> +#include <linux/mod_devicetable.h>
> +
> +#include "fsi-master-i2cr.h"
> +#include "fsi-slave.h"
> +
> +struct i2cr_scom {
> +	struct device dev;
> +	struct cdev cdev;
> +	struct fsi_master_i2cr *i2cr;
> +};
> +
> +static loff_t i2cr_scom_llseek(struct file *file, loff_t offset, int whence)
> +{
> +	switch (whence) {
> +	case SEEK_CUR:
> +		break;
> +	case SEEK_SET:
> +		file->f_pos = offset;
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	return offset;
> +}
> +
> +static ssize_t i2cr_scom_read(struct file *filep, char __user *buf, size_t len, loff_t *offset)
> +{
> +	struct i2cr_scom *scom = filep->private_data;
> +	u64 data;
> +	int ret;
> +
> +	if (len != sizeof(data))
> +		return -EINVAL;
> +
> +	ret = fsi_master_i2cr_read(scom->i2cr, (u32)*offset, &data);
> +	if (ret)
> +		return ret;
> +
> +	ret = copy_to_user(buf, &data, len);
> +	if (ret)
> +		return ret;
> +
> +	return len;
> +}
> +
> +static ssize_t i2cr_scom_write(struct file *filep, const char __user *buf, size_t len,
> +			       loff_t *offset)
> +{
> +	struct i2cr_scom *scom = filep->private_data;
> +	u64 data;
> +	int ret;
> +
> +	if (len != sizeof(data))
> +		return -EINVAL;
> +
> +	ret = copy_from_user(&data, buf, len);
> +	if (ret)
> +		return ret;
> +
> +	ret = fsi_master_i2cr_write(scom->i2cr, (u32)*offset, data);
> +	if (ret)
> +		return ret;
> +
> +	return len;
> +}
> +
> +static const struct file_operations i2cr_scom_fops = {
> +	.owner		= THIS_MODULE,
> +	.open		= simple_open,
> +	.llseek		= i2cr_scom_llseek,
> +	.read		= i2cr_scom_read,
> +	.write		= i2cr_scom_write,
> +};
> +
> +static int i2cr_scom_probe(struct device *dev)
> +{
> +	struct fsi_device *fsi_dev = to_fsi_dev(dev);
> +	struct i2cr_scom *scom;
> +	int didx;
> +	int ret;
> +
> +	if (!is_fsi_master_i2cr(fsi_dev->slave->master))
> +		return -ENODEV;
> +
> +	scom = devm_kzalloc(dev, sizeof(*scom), GFP_KERNEL);
> +	if (!scom)
> +		return -ENOMEM;
> +
> +	scom->i2cr = to_fsi_master_i2cr(fsi_dev->slave->master);
> +	dev_set_drvdata(dev, scom);
> +
> +	scom->dev.type = &fsi_cdev_type;
> +	scom->dev.parent = dev;
> +	device_initialize(&scom->dev);
> +
> +	ret = fsi_get_new_minor(fsi_dev, fsi_dev_scom, &scom->dev.devt, &didx);
> +	if (ret)
> +		return ret;
> +
> +	dev_set_name(&scom->dev, "scom%d", didx);
> +	cdev_init(&scom->cdev, &i2cr_scom_fops);
> +	ret = cdev_device_add(&scom->cdev, &scom->dev);
> +	if (ret)
> +		fsi_free_minor(scom->dev.devt);
> +
> +	return ret;
> +}
> +
> +static int i2cr_scom_remove(struct device *dev)
> +{
> +	struct i2cr_scom *scom = dev_get_drvdata(dev);
> +
> +	cdev_device_del(&scom->cdev, &scom->dev);
> +	fsi_free_minor(scom->dev.devt);
> +
> +	return 0;
> +}
> +
> +static const struct of_device_id i2cr_scom_of_ids[] = {
> +	{ .compatible = "ibm,i2cr-scom" },

This is not documented. Please add a binding.

Rob
diff mbox series

Patch

diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig
index 999be82720c5..79a31593618a 100644
--- a/drivers/fsi/Kconfig
+++ b/drivers/fsi/Kconfig
@@ -94,4 +94,12 @@  config FSI_OCC
 	provide the raw sensor data as well as perform thermal and power
 	management on the system.
 
+config I2CR_SCOM
+	tristate "IBM I2C Responder SCOM driver"
+	depends on FSI_MASTER_I2CR
+	help
+	  This option enables an I2C Responder based SCOM device driver. The
+	  I2CR has the capability to directly perform SCOM operations instead
+	  of using the FSI2PIB engine.
+
 endif
diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile
index 34dbaa1c452e..5550aa15e0b1 100644
--- a/drivers/fsi/Makefile
+++ b/drivers/fsi/Makefile
@@ -9,3 +9,4 @@  obj-$(CONFIG_FSI_MASTER_AST_CF) += fsi-master-ast-cf.o
 obj-$(CONFIG_FSI_SCOM) += fsi-scom.o
 obj-$(CONFIG_FSI_SBEFIFO) += fsi-sbefifo.o
 obj-$(CONFIG_FSI_OCC) += fsi-occ.o
+obj-$(CONFIG_I2CR_SCOM) += i2cr-scom.o
diff --git a/drivers/fsi/i2cr-scom.c b/drivers/fsi/i2cr-scom.c
new file mode 100644
index 000000000000..cb7e02213032
--- /dev/null
+++ b/drivers/fsi/i2cr-scom.c
@@ -0,0 +1,154 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) IBM Corporation 2023 */
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/fsi.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+
+#include "fsi-master-i2cr.h"
+#include "fsi-slave.h"
+
+struct i2cr_scom {
+	struct device dev;
+	struct cdev cdev;
+	struct fsi_master_i2cr *i2cr;
+};
+
+static loff_t i2cr_scom_llseek(struct file *file, loff_t offset, int whence)
+{
+	switch (whence) {
+	case SEEK_CUR:
+		break;
+	case SEEK_SET:
+		file->f_pos = offset;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return offset;
+}
+
+static ssize_t i2cr_scom_read(struct file *filep, char __user *buf, size_t len, loff_t *offset)
+{
+	struct i2cr_scom *scom = filep->private_data;
+	u64 data;
+	int ret;
+
+	if (len != sizeof(data))
+		return -EINVAL;
+
+	ret = fsi_master_i2cr_read(scom->i2cr, (u32)*offset, &data);
+	if (ret)
+		return ret;
+
+	ret = copy_to_user(buf, &data, len);
+	if (ret)
+		return ret;
+
+	return len;
+}
+
+static ssize_t i2cr_scom_write(struct file *filep, const char __user *buf, size_t len,
+			       loff_t *offset)
+{
+	struct i2cr_scom *scom = filep->private_data;
+	u64 data;
+	int ret;
+
+	if (len != sizeof(data))
+		return -EINVAL;
+
+	ret = copy_from_user(&data, buf, len);
+	if (ret)
+		return ret;
+
+	ret = fsi_master_i2cr_write(scom->i2cr, (u32)*offset, data);
+	if (ret)
+		return ret;
+
+	return len;
+}
+
+static const struct file_operations i2cr_scom_fops = {
+	.owner		= THIS_MODULE,
+	.open		= simple_open,
+	.llseek		= i2cr_scom_llseek,
+	.read		= i2cr_scom_read,
+	.write		= i2cr_scom_write,
+};
+
+static int i2cr_scom_probe(struct device *dev)
+{
+	struct fsi_device *fsi_dev = to_fsi_dev(dev);
+	struct i2cr_scom *scom;
+	int didx;
+	int ret;
+
+	if (!is_fsi_master_i2cr(fsi_dev->slave->master))
+		return -ENODEV;
+
+	scom = devm_kzalloc(dev, sizeof(*scom), GFP_KERNEL);
+	if (!scom)
+		return -ENOMEM;
+
+	scom->i2cr = to_fsi_master_i2cr(fsi_dev->slave->master);
+	dev_set_drvdata(dev, scom);
+
+	scom->dev.type = &fsi_cdev_type;
+	scom->dev.parent = dev;
+	device_initialize(&scom->dev);
+
+	ret = fsi_get_new_minor(fsi_dev, fsi_dev_scom, &scom->dev.devt, &didx);
+	if (ret)
+		return ret;
+
+	dev_set_name(&scom->dev, "scom%d", didx);
+	cdev_init(&scom->cdev, &i2cr_scom_fops);
+	ret = cdev_device_add(&scom->cdev, &scom->dev);
+	if (ret)
+		fsi_free_minor(scom->dev.devt);
+
+	return ret;
+}
+
+static int i2cr_scom_remove(struct device *dev)
+{
+	struct i2cr_scom *scom = dev_get_drvdata(dev);
+
+	cdev_device_del(&scom->cdev, &scom->dev);
+	fsi_free_minor(scom->dev.devt);
+
+	return 0;
+}
+
+static const struct of_device_id i2cr_scom_of_ids[] = {
+	{ .compatible = "ibm,i2cr-scom" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, i2cr_scom_of_ids);
+
+static const struct fsi_device_id i2cr_scom_ids[] = {
+	{ 0x5, FSI_VERSION_ANY },
+	{ }
+};
+
+static struct fsi_driver i2cr_scom_driver = {
+	.id_table = i2cr_scom_ids,
+	.drv = {
+		.name = "i2cr_scom",
+		.bus = &fsi_bus_type,
+		.of_match_table = i2cr_scom_of_ids,
+		.probe = i2cr_scom_probe,
+		.remove = i2cr_scom_remove,
+	}
+};
+
+module_fsi_driver(i2cr_scom_driver);
+
+MODULE_AUTHOR("Eddie James <eajames@linux.ibm.com>");
+MODULE_DESCRIPTION("IBM I2C Responder SCOM driver");
+MODULE_LICENSE("GPL");