Commit 79d2c8be authored by Daniel Drake's avatar Daniel Drake Committed by Linus Walleij

pinctrl/amd: save pin registers over suspend/resume

The touchpad in the Asus laptop models X505BA/BP and X542BA/BP is
unresponsive after suspend/resume. The following error appears during
resume:

  i2c_hid i2c-ELAN1300:00: failed to reset device.

The problem here is that i2c_hid does not notice the interrupt being
generated at this point, because the GPIO is no longer configured
for interrupts.

Fix this by saving pinctrl-amd pin registers during suspend and
restoring them at resume time.

Based on code from pinctrl-intel.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarDaniel Drake <drake@endlessm.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent a9a1a483
......@@ -36,6 +36,7 @@
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include "core.h"
#include "pinctrl-utils.h"
#include "pinctrl-amd.h"
......@@ -725,6 +726,69 @@ static const struct pinconf_ops amd_pinconf_ops = {
.pin_config_group_set = amd_pinconf_group_set,
};
#ifdef CONFIG_PM_SLEEP
static bool amd_gpio_should_save(struct amd_gpio *gpio_dev, unsigned int pin)
{
const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);
if (!pd)
return false;
/*
* Only restore the pin if it is actually in use by the kernel (or
* by userspace).
*/
if (pd->mux_owner || pd->gpio_owner ||
gpiochip_line_is_irq(&gpio_dev->gc, pin))
return true;
return false;
}
int amd_gpio_suspend(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct amd_gpio *gpio_dev = platform_get_drvdata(pdev);
struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
int i;
for (i = 0; i < desc->npins; i++) {
int pin = desc->pins[i].number;
if (!amd_gpio_should_save(gpio_dev, pin))
continue;
gpio_dev->saved_regs[i] = readl(gpio_dev->base + pin*4);
}
return 0;
}
int amd_gpio_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct amd_gpio *gpio_dev = platform_get_drvdata(pdev);
struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
int i;
for (i = 0; i < desc->npins; i++) {
int pin = desc->pins[i].number;
if (!amd_gpio_should_save(gpio_dev, pin))
continue;
writel(gpio_dev->saved_regs[i], gpio_dev->base + pin*4);
}
return 0;
}
static const struct dev_pm_ops amd_gpio_pm_ops = {
SET_LATE_SYSTEM_SLEEP_PM_OPS(amd_gpio_suspend,
amd_gpio_resume)
};
#endif
static struct pinctrl_desc amd_pinctrl_desc = {
.pins = kerncz_pins,
.npins = ARRAY_SIZE(kerncz_pins),
......@@ -764,6 +828,14 @@ static int amd_gpio_probe(struct platform_device *pdev)
return irq_base;
}
#ifdef CONFIG_PM_SLEEP
gpio_dev->saved_regs = devm_kcalloc(&pdev->dev, amd_pinctrl_desc.npins,
sizeof(*gpio_dev->saved_regs),
GFP_KERNEL);
if (!gpio_dev->saved_regs)
return -ENOMEM;
#endif
gpio_dev->pdev = pdev;
gpio_dev->gc.direction_input = amd_gpio_direction_input;
gpio_dev->gc.direction_output = amd_gpio_direction_output;
......@@ -853,6 +925,9 @@ static struct platform_driver amd_gpio_driver = {
.driver = {
.name = "amd_gpio",
.acpi_match_table = ACPI_PTR(amd_gpio_acpi_match),
#ifdef CONFIG_PM_SLEEP
.pm = &amd_gpio_pm_ops,
#endif
},
.probe = amd_gpio_probe,
.remove = amd_gpio_remove,
......
......@@ -97,6 +97,7 @@ struct amd_gpio {
unsigned int hwbank_num;
struct resource *res;
struct platform_device *pdev;
u32 *saved_regs;
};
/* KERNCZ configuration*/
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment