From: Eddie James Date: Mon, 12 Jun 2023 19:56:57 +0000 (-0500) Subject: fsi: Add I2C Responder SCOM driver X-Git-Tag: v6.6.7~2016^2~43^2~3 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c0b34bed0bbf7a058dab52d45e9aeb92bbe4c637;p=platform%2Fkernel%2Flinux-starfive.git fsi: Add I2C Responder SCOM driver 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 Link: https://lore.kernel.org/r/20230612195657.245125-15-eajames@linux.ibm.com Signed-off-by: Joel Stanley --- diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig index 999be82..79a3159 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 34dbaa1..5550aa1 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 0000000..cb7e022 --- /dev/null +++ b/drivers/fsi/i2cr-scom.c @@ -0,0 +1,154 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) IBM Corporation 2023 */ + +#include +#include +#include +#include +#include +#include + +#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 "); +MODULE_DESCRIPTION("IBM I2C Responder SCOM driver"); +MODULE_LICENSE("GPL");