[v7,4/7] fsi: Add I2C Responder SCOM driver
Commit Message
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>
---
Changes since v6:
- Update SCOM driver with newer interfaces and drop BE conversion
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
Hi Eddie,
I love your patch! Yet something to improve:
[auto build test ERROR on robh/for-next]
[also build test ERROR on linus/master v6.2 next-20230303]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Eddie-James/fsi-Move-fsi_slave-structure-definition-to-header/20230304-011530
base: https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
patch link: https://lore.kernel.org/r/20230303170416.1347530-5-eajames%40linux.ibm.com
patch subject: [PATCH v7 4/7] fsi: Add I2C Responder SCOM driver
config: powerpc-allmodconfig (https://download.01.org/0day-ci/archive/20230304/202303042033.kC3KNCW2-lkp@intel.com/config)
compiler: powerpc-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/36d0c348a48344d2ffef15d5abefe139fc511684
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Eddie-James/fsi-Move-fsi_slave-structure-definition-to-header/20230304-011530
git checkout 36d0c348a48344d2ffef15d5abefe139fc511684
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202303042033.kC3KNCW2-lkp@intel.com/
All errors (new ones prefixed by >>, old ones prefixed by <<):
>> ERROR: modpost: "fsi_master_i2cr_read" [drivers/fsi/i2cr-scom.ko] undefined!
>> ERROR: modpost: "fsi_master_i2cr_write" [drivers/fsi/i2cr-scom.ko] undefined!
@@ -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
@@ -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
new file mode 100644
@@ -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 (!(fsi_dev->slave->master->flags & FSI_MASTER_FLAG_I2CR))
+ 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");