lkml.org 
[lkml]   [2020]   [Aug]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH v2 1/3] platform/x86: Add Intel Input Output Manager (IOM) driver
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@intel.com>
> ---

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@intel.com>");
> +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

\
 
 \ /
  Last update: 2020-08-22 11:57    [W:0.084 / U:3.812 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site