From 79d2c8bede2c93f9432d7da0bc2f76a195c90fc0 Mon Sep 17 00:00:00 2001 From: Daniel Drake Date: Mon, 11 Sep 2017 14:11:56 +0800 Subject: [PATCH] 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: Daniel Drake Signed-off-by: Linus Walleij --- drivers/pinctrl/pinctrl-amd.c | 75 +++++++++++++++++++++++++++++++++++ drivers/pinctrl/pinctrl-amd.h | 1 + 2 files changed, 76 insertions(+) diff --git a/drivers/pinctrl/pinctrl-amd.c b/drivers/pinctrl/pinctrl-amd.c index 38af1ec2df0c..3f6b34febbf1 100644 --- a/drivers/pinctrl/pinctrl-amd.c +++ b/drivers/pinctrl/pinctrl-amd.c @@ -36,6 +36,7 @@ #include #include +#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, diff --git a/drivers/pinctrl/pinctrl-amd.h b/drivers/pinctrl/pinctrl-amd.h index 5b1cb965c767..8fa453a59da5 100644 --- a/drivers/pinctrl/pinctrl-amd.h +++ b/drivers/pinctrl/pinctrl-amd.h @@ -97,6 +97,7 @@ struct amd_gpio { unsigned int hwbank_num; struct resource *res; struct platform_device *pdev; + u32 *saved_regs; }; /* KERNCZ configuration*/ -- 2.20.1