Hi Rajmohan, On Fri, Aug 21, 2020 at 09:05:06PM -0700, Rajmohan Mani wrote: > Input Output Manager (IOM) is part of the Tiger Lake SoC that > configures the Type-C Sub System (TCSS). IOM is a micro controller > that handles Type-C topology, configuration and PM functions of > various Type-C devices connected on the platform. > > This driver helps read relevant information such as Type-C port > status (whether a device is connected to a Type-C port or not) and > the activity type on the Type-C ports (such as USB, Display Port, > Thunderbolt), for consumption by other drivers. > > Currently intel_iom_port_status() API is exported by this driver, > that has information about the Type-C port status and port activity > type. > > Signed-off-by: Rajmohan Mani <rajmohan.mani@xxxxxxxxx> > --- Perhaps include a version log of changes since v1? > diff --git a/drivers/platform/x86/intel_iom.c b/drivers/platform/x86/intel_iom.c > new file mode 100644 > index 000000000000..cda7716410c6 > --- /dev/null > +++ b/drivers/platform/x86/intel_iom.c > +int intel_iom_port_status(u8 port, u32 *status) > +{ > + void __iomem *reg; > + > + if (!iom || !iom->dev || !iom->regbar) Do we need to check for !iom->dev and !iom->regbar? Is there a valid situation where iom != NULL but iom->dev and/or iom->regbar == NULL? Sounds like it shouldn't, but I may be missing something. > + return -ENODEV; > + > + if (!status || (port > IOM_MAX_PORTS - 1)) I think parentheses around "port > IOM_MAX_PORT - 1" aren't required. > + return -EINVAL; > + > + reg = iom->regbar + IOM_PORT_STATUS_OFFSET + IOM_REG_LEN * port; > + > + *status = ioread32(reg); Perhaps just inline reg within the parentheses? > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(intel_iom_port_status); > + > +static int intel_iom_probe(struct platform_device *pdev) > +{ > + void __iomem *addr; > + > + /* only one IOM device is supported */ Minor nit: s/only/Only > + if (iom) > + return -EBUSY; > + > + iom = devm_kzalloc(&pdev->dev, sizeof(*iom), GFP_KERNEL); > + if (!iom) > + return -ENOMEM; > + > + addr = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(addr)) > + return PTR_ERR(addr); > + > + iom->regbar = addr; > + iom->dev = &pdev->dev; > + > + return 0; > +} > + > +static const struct acpi_device_id intel_iom_acpi_ids[] = { > + { "INTC1072" }, > + {} > +}; > +MODULE_DEVICE_TABLE(acpi, intel_iom_acpi_ids); > + > +static struct platform_driver intel_iom_driver = { > + .probe = intel_iom_probe, nit: I generally see ".probe" listed below ".driver". > + .driver = { > + .name = "intel_iom", > + .acpi_match_table = intel_iom_acpi_ids, > + }, > +}; > + > +module_platform_driver_probe(intel_iom_driver, intel_iom_probe); > + > +MODULE_AUTHOR("Rajmohan Mani <rajmohan.mani@xxxxxxxxx>"); > +MODULE_DESCRIPTION("Intel IOM driver"); > +MODULE_LICENSE("GPL v2"); > diff --git a/include/linux/platform_data/x86/intel_iom.h b/include/linux/platform_data/x86/intel_iom.h > new file mode 100644 > index 000000000000..e4c9a305e7a9 > --- /dev/null > +++ b/include/linux/platform_data/x86/intel_iom.h > @@ -0,0 +1,49 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > + > +#ifndef _PLATFORM_DATA_X86_INTEL_IOM_H_ > +#define _PLATFORM_DATA_X86_INTEL_IOM_H_ > + > + > +#define IOM_MAX_PORTS 4 > +/* Register length in bytes */ > +#define IOM_REG_LEN 4 Do these two #define's need to be in the header, instead of directly in intel_iom.c ? > + > +#ifdef CONFIG_ACPI > + > +int intel_iom_port_status(u8 port, u32 *status); > + > +#else > + > +int intel_iom_port_status(struct intel_iom *iom, u8 port, u32 *status) Should the function signature be the same as the #ifdef case? Best regards, -Prashant