028af5941d
Intel Skylake the LPSS I2C pad circuit has internal delays that require programming non-zero SDA hold time for the I2C host controller. If this is not done communication to slave devices may fail with arbitration lost errors like the one seen below taken from Lenovo Yoga 900: i2c_hid i2c-SYNA2B29:00: Fetching the HID descriptor i2c_hid i2c-SYNA2B29:00: __i2c_hid_command: cmd=20 00 i2c_designware i2c_designware.1: i2c_dw_handle_tx_abort: lost arbitration To fix this we follow what the Windows driver is doing and pass the default SDA hold time of 230 ns to all Intel Skylake host controllers. This still allows the platform to override these values by passing special ACPI methods SSCN and FMCN. Reported-by: Kevin Fenzi <kevin@scrye.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
116 lines
2.9 KiB
C
116 lines
2.9 KiB
C
/*
|
|
* Intel LPSS ACPI support.
|
|
*
|
|
* Copyright (C) 2015, Intel Corporation
|
|
*
|
|
* Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
|
|
* Mika Westerberg <mika.westerberg@linux.intel.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
#include <linux/acpi.h>
|
|
#include <linux/ioport.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pm.h>
|
|
#include <linux/pm_runtime.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/property.h>
|
|
|
|
#include "intel-lpss.h"
|
|
|
|
static const struct intel_lpss_platform_info spt_info = {
|
|
.clk_rate = 120000000,
|
|
};
|
|
|
|
static struct property_entry spt_i2c_properties[] = {
|
|
PROPERTY_ENTRY_U32("i2c-sda-hold-time-ns", 230),
|
|
{ },
|
|
};
|
|
|
|
static struct property_set spt_i2c_pset = {
|
|
.properties = spt_i2c_properties,
|
|
};
|
|
|
|
static const struct intel_lpss_platform_info spt_i2c_info = {
|
|
.clk_rate = 120000000,
|
|
.pset = &spt_i2c_pset,
|
|
};
|
|
|
|
static const struct intel_lpss_platform_info bxt_info = {
|
|
.clk_rate = 100000000,
|
|
};
|
|
|
|
static const struct intel_lpss_platform_info bxt_i2c_info = {
|
|
.clk_rate = 133000000,
|
|
};
|
|
|
|
static const struct acpi_device_id intel_lpss_acpi_ids[] = {
|
|
/* SPT */
|
|
{ "INT3446", (kernel_ulong_t)&spt_i2c_info },
|
|
{ "INT3447", (kernel_ulong_t)&spt_i2c_info },
|
|
/* BXT */
|
|
{ "80860AAC", (kernel_ulong_t)&bxt_i2c_info },
|
|
{ "80860ABC", (kernel_ulong_t)&bxt_info },
|
|
{ "80860AC2", (kernel_ulong_t)&bxt_info },
|
|
/* APL */
|
|
{ "80865AAC", (kernel_ulong_t)&bxt_i2c_info },
|
|
{ "80865ABC", (kernel_ulong_t)&bxt_info },
|
|
{ "80865AC2", (kernel_ulong_t)&bxt_info },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, intel_lpss_acpi_ids);
|
|
|
|
static int intel_lpss_acpi_probe(struct platform_device *pdev)
|
|
{
|
|
struct intel_lpss_platform_info *info;
|
|
const struct acpi_device_id *id;
|
|
|
|
id = acpi_match_device(intel_lpss_acpi_ids, &pdev->dev);
|
|
if (!id)
|
|
return -ENODEV;
|
|
|
|
info = devm_kmemdup(&pdev->dev, (void *)id->driver_data, sizeof(*info),
|
|
GFP_KERNEL);
|
|
if (!info)
|
|
return -ENOMEM;
|
|
|
|
info->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
info->irq = platform_get_irq(pdev, 0);
|
|
|
|
pm_runtime_set_active(&pdev->dev);
|
|
pm_runtime_enable(&pdev->dev);
|
|
|
|
return intel_lpss_probe(&pdev->dev, info);
|
|
}
|
|
|
|
static int intel_lpss_acpi_remove(struct platform_device *pdev)
|
|
{
|
|
intel_lpss_remove(&pdev->dev);
|
|
pm_runtime_disable(&pdev->dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static INTEL_LPSS_PM_OPS(intel_lpss_acpi_pm_ops);
|
|
|
|
static struct platform_driver intel_lpss_acpi_driver = {
|
|
.probe = intel_lpss_acpi_probe,
|
|
.remove = intel_lpss_acpi_remove,
|
|
.driver = {
|
|
.name = "intel-lpss",
|
|
.acpi_match_table = intel_lpss_acpi_ids,
|
|
.pm = &intel_lpss_acpi_pm_ops,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(intel_lpss_acpi_driver);
|
|
|
|
MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
|
|
MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
|
|
MODULE_DESCRIPTION("Intel LPSS ACPI driver");
|
|
MODULE_LICENSE("GPL v2");
|