summaryrefslogtreecommitdiffstats
path: root/drivers/gpio
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/gpio-omap.c331
1 files changed, 227 insertions, 104 deletions
diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
index e81008678a38..c0d7ae766de4 100644
--- a/drivers/gpio/gpio-omap.c
+++ b/drivers/gpio/gpio-omap.c
@@ -19,6 +19,7 @@
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
+#include <linux/cpu_pm.h>
#include <linux/device.h>
#include <linux/pm_runtime.h>
#include <linux/pm.h>
@@ -28,9 +29,11 @@
#include <linux/bitops.h>
#include <linux/platform_data/gpio-omap.h>
-#define OFF_MODE 1
#define OMAP4_GPIO_DEBOUNCINGTIME_MASK 0xFF
+#define OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER BIT(2)
+#define OMAP_GPIO_QUIRK_DEFERRED_WKUP_EN BIT(1)
+
static LIST_HEAD(omap_gpio_list);
struct gpio_regs {
@@ -48,6 +51,13 @@ struct gpio_regs {
u32 debounce_en;
};
+struct gpio_bank;
+
+struct gpio_omap_funcs {
+ void (*idle_enable_level_quirk)(struct gpio_bank *bank);
+ void (*idle_disable_level_quirk)(struct gpio_bank *bank);
+};
+
struct gpio_bank {
struct list_head node;
void __iomem *base;
@@ -55,6 +65,7 @@ struct gpio_bank {
u32 non_wakeup_gpios;
u32 enabled_non_wakeup_gpios;
struct gpio_regs context;
+ struct gpio_omap_funcs funcs;
u32 saved_datain;
u32 level_mask;
u32 toggle_mask;
@@ -62,6 +73,8 @@ struct gpio_bank {
raw_spinlock_t wa_lock;
struct gpio_chip chip;
struct clk *dbck;
+ struct notifier_block nb;
+ unsigned int is_suspended:1;
u32 mod_usage;
u32 irq_usage;
u32 dbck_enable_mask;
@@ -73,8 +86,8 @@ struct gpio_bank {
int stride;
u32 width;
int context_loss_count;
- int power_mode;
bool workaround_enabled;
+ u32 quirks;
void (*set_dataout)(struct gpio_bank *bank, unsigned gpio, int enable);
void (*set_dataout_multiple)(struct gpio_bank *bank,
@@ -368,9 +381,18 @@ static inline void omap_set_gpio_trigger(struct gpio_bank *bank, int gpio,
readl_relaxed(bank->base + bank->regs->fallingdetect);
if (likely(!(bank->non_wakeup_gpios & gpio_bit))) {
- omap_gpio_rmw(base, bank->regs->wkup_en, gpio_bit, trigger != 0);
- bank->context.wake_en =
- readl_relaxed(bank->base + bank->regs->wkup_en);
+ /* Defer wkup_en register update until we idle? */
+ if (bank->quirks & OMAP_GPIO_QUIRK_DEFERRED_WKUP_EN) {
+ if (trigger)
+ bank->context.wake_en |= gpio_bit;
+ else
+ bank->context.wake_en &= ~gpio_bit;
+ } else {
+ omap_gpio_rmw(base, bank->regs->wkup_en, gpio_bit,
+ trigger != 0);
+ bank->context.wake_en =
+ readl_relaxed(bank->base + bank->regs->wkup_en);
+ }
}
/* This part needs to be executed always for OMAP{34xx, 44xx} */
@@ -741,7 +763,9 @@ static irqreturn_t omap_gpio_irq_handler(int irq, void *gpiobank)
if (WARN_ON(!isr_reg))
goto exit;
- pm_runtime_get_sync(bank->chip.parent);
+ if (WARN_ONCE(!pm_runtime_active(bank->chip.parent),
+ "gpio irq%i while runtime suspended?\n", irq))
+ return IRQ_NONE;
while (1) {
raw_spin_lock_irqsave(&bank->lock, lock_flags);
@@ -792,7 +816,6 @@ static irqreturn_t omap_gpio_irq_handler(int irq, void *gpiobank)
}
}
exit:
- pm_runtime_put(bank->chip.parent);
return IRQ_HANDLED;
}
@@ -899,6 +922,82 @@ static void omap_gpio_unmask_irq(struct irq_data *d)
raw_spin_unlock_irqrestore(&bank->lock, flags);
}
+/*
+ * Only edges can generate a wakeup event to the PRCM.
+ *
+ * Therefore, ensure any wake-up capable GPIOs have
+ * edge-detection enabled before going idle to ensure a wakeup
+ * to the PRCM is generated on a GPIO transition. (c.f. 34xx
+ * NDA TRM 25.5.3.1)
+ *
+ * The normal values will be restored upon ->runtime_resume()
+ * by writing back the values saved in bank->context.
+ */
+static void __maybe_unused
+omap2_gpio_enable_level_quirk(struct gpio_bank *bank)
+{
+ u32 wake_low, wake_hi;
+
+ /* Enable additional edge detection for level gpios for idle */
+ wake_low = bank->context.leveldetect0 & bank->context.wake_en;
+ if (wake_low)
+ writel_relaxed(wake_low | bank->context.fallingdetect,
+ bank->base + bank->regs->fallingdetect);
+
+ wake_hi = bank->context.leveldetect1 & bank->context.wake_en;
+ if (wake_hi)
+ writel_relaxed(wake_hi | bank->context.risingdetect,
+ bank->base + bank->regs->risingdetect);
+}
+
+static void __maybe_unused
+omap2_gpio_disable_level_quirk(struct gpio_bank *bank)
+{
+ /* Disable edge detection for level gpios after idle */
+ writel_relaxed(bank->context.fallingdetect,
+ bank->base + bank->regs->fallingdetect);
+ writel_relaxed(bank->context.risingdetect,
+ bank->base + bank->regs->risingdetect);
+}
+
+/*
+ * On omap4 and later SoC variants a level interrupt with wkup_en
+ * enabled blocks the GPIO functional clock from idling until the GPIO
+ * instance has been reset. To avoid that, we must set wkup_en only for
+ * idle for level interrupts, and clear level registers for the duration
+ * of idle. The level interrupts will be still there on wakeup by their
+ * nature.
+ */
+static void __maybe_unused
+omap4_gpio_enable_level_quirk(struct gpio_bank *bank)
+{
+ /* Update wake register for idle, edge bits might be already set */
+ writel_relaxed(bank->context.wake_en,
+ bank->base + bank->regs->wkup_en);
+
+ /* Clear level registers for idle */
+ writel_relaxed(0, bank->base + bank->regs->leveldetect0);
+ writel_relaxed(0, bank->base + bank->regs->leveldetect1);
+}
+
+static void __maybe_unused
+omap4_gpio_disable_level_quirk(struct gpio_bank *bank)
+{
+ /* Restore level registers after idle */
+ writel_relaxed(bank->context.leveldetect0,
+ bank->base + bank->regs->leveldetect0);
+ writel_relaxed(bank->context.leveldetect1,
+ bank->base + bank->regs->leveldetect1);
+
+ /* Clear saved wkup_en for level, it will be set for next idle again */
+ bank->context.wake_en &= ~(bank->context.leveldetect0 |
+ bank->context.leveldetect1);
+
+ /* Update wake with only edge configuration */
+ writel_relaxed(bank->context.wake_en,
+ bank->base + bank->regs->wkup_en);
+}
+
/*---------------------------------------------------------------------*/
static int omap_mpuio_suspend_noirq(struct device *dev)
@@ -1218,6 +1317,38 @@ static int omap_gpio_chip_init(struct gpio_bank *bank, struct irq_chip *irqc)
return ret;
}
+static void omap_gpio_idle(struct gpio_bank *bank, bool may_lose_context);
+static void omap_gpio_unidle(struct gpio_bank *bank);
+
+static int gpio_omap_cpu_notifier(struct notifier_block *nb,
+ unsigned long cmd, void *v)
+{
+ struct gpio_bank *bank;
+ struct device *dev;
+ unsigned long flags;
+
+ bank = container_of(nb, struct gpio_bank, nb);
+ dev = bank->chip.parent;
+
+ raw_spin_lock_irqsave(&bank->lock, flags);
+ switch (cmd) {
+ case CPU_CLUSTER_PM_ENTER:
+ if (bank->is_suspended)
+ break;
+ omap_gpio_idle(bank, true);
+ break;
+ case CPU_CLUSTER_PM_ENTER_FAILED:
+ case CPU_CLUSTER_PM_EXIT:
+ if (bank->is_suspended)
+ break;
+ omap_gpio_unidle(bank);
+ break;
+ }
+ raw_spin_unlock_irqrestore(&bank->lock, flags);
+
+ return NOTIFY_OK;
+}
+
static const struct of_device_id omap_gpio_match[];
static int omap_gpio_probe(struct platform_device *pdev)
@@ -1270,6 +1401,7 @@ static int omap_gpio_probe(struct platform_device *pdev)
bank->chip.parent = dev;
bank->chip.owner = THIS_MODULE;
bank->dbck_flag = pdata->dbck_flag;
+ bank->quirks = pdata->quirks;
bank->stride = pdata->bank_stride;
bank->width = pdata->bank_width;
bank->is_mpuio = pdata->is_mpuio;
@@ -1278,6 +1410,7 @@ static int omap_gpio_probe(struct platform_device *pdev)
#ifdef CONFIG_OF_GPIO
bank->chip.of_node = of_node_get(node);
#endif
+
if (node) {
if (!of_property_read_bool(node, "ti,gpio-always-on"))
bank->loses_context = true;
@@ -1298,6 +1431,18 @@ static int omap_gpio_probe(struct platform_device *pdev)
omap_set_gpio_dataout_mask_multiple;
}
+ if (bank->quirks & OMAP_GPIO_QUIRK_DEFERRED_WKUP_EN) {
+ bank->funcs.idle_enable_level_quirk =
+ omap4_gpio_enable_level_quirk;
+ bank->funcs.idle_disable_level_quirk =
+ omap4_gpio_disable_level_quirk;
+ } else if (bank->quirks & OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER) {
+ bank->funcs.idle_enable_level_quirk =
+ omap2_gpio_enable_level_quirk;
+ bank->funcs.idle_disable_level_quirk =
+ omap2_gpio_disable_level_quirk;
+ }
+
raw_spin_lock_init(&bank->lock);
raw_spin_lock_init(&bank->wa_lock);
@@ -1322,7 +1467,6 @@ static int omap_gpio_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, bank);
pm_runtime_enable(dev);
- pm_runtime_irq_safe(dev);
pm_runtime_get_sync(dev);
if (bank->is_mpuio)
@@ -1341,6 +1485,12 @@ static int omap_gpio_probe(struct platform_device *pdev)
omap_gpio_show_rev(bank);
+ if (bank->funcs.idle_enable_level_quirk &&
+ bank->funcs.idle_disable_level_quirk) {
+ bank->nb.notifier_call = gpio_omap_cpu_notifier;
+ cpu_pm_register_notifier(&bank->nb);
+ }
+
pm_runtime_put(dev);
list_add_tail(&bank->node, &omap_gpio_list);
@@ -1352,6 +1502,8 @@ static int omap_gpio_remove(struct platform_device *pdev)
{
struct gpio_bank *bank = platform_get_drvdata(pdev);
+ if (bank->nb.notifier_call)
+ cpu_pm_unregister_notifier(&bank->nb);
list_del(&bank->node);
gpiochip_remove(&bank->chip);
pm_runtime_disable(&pdev->dev);
@@ -1361,48 +1513,22 @@ static int omap_gpio_remove(struct platform_device *pdev)
return 0;
}
-#ifdef CONFIG_ARCH_OMAP2PLUS
-
-#if defined(CONFIG_PM)
static void omap_gpio_restore_context(struct gpio_bank *bank);
-static int omap_gpio_runtime_suspend(struct device *dev)
+static void omap_gpio_idle(struct gpio_bank *bank, bool may_lose_context)
{
- struct platform_device *pdev = to_platform_device(dev);
- struct gpio_bank *bank = platform_get_drvdata(pdev);
+ struct device *dev = bank->chip.parent;
u32 l1 = 0, l2 = 0;
- unsigned long flags;
- u32 wake_low, wake_hi;
-
- raw_spin_lock_irqsave(&bank->lock, flags);
- /*
- * Only edges can generate a wakeup event to the PRCM.
- *
- * Therefore, ensure any wake-up capable GPIOs have
- * edge-detection enabled before going idle to ensure a wakeup
- * to the PRCM is generated on a GPIO transition. (c.f. 34xx
- * NDA TRM 25.5.3.1)
- *
- * The normal values will be restored upon ->runtime_resume()
- * by writing back the values saved in bank->context.
- */
- wake_low = bank->context.leveldetect0 & bank->context.wake_en;
- if (wake_low)
- writel_relaxed(wake_low | bank->context.fallingdetect,
- bank->base + bank->regs->fallingdetect);
- wake_hi = bank->context.leveldetect1 & bank->context.wake_en;
- if (wake_hi)
- writel_relaxed(wake_hi | bank->context.risingdetect,
- bank->base + bank->regs->risingdetect);
+ if (bank->funcs.idle_enable_level_quirk)
+ bank->funcs.idle_enable_level_quirk(bank);
if (!bank->enabled_non_wakeup_gpios)
goto update_gpio_context_count;
- if (bank->power_mode != OFF_MODE) {
- bank->power_mode = 0;
+ if (!may_lose_context)
goto update_gpio_context_count;
- }
+
/*
* If going to OFF, remove triggering for all
* non-wakeup GPIOs. Otherwise spurious IRQs will be
@@ -1427,23 +1553,16 @@ update_gpio_context_count:
bank->get_context_loss_count(dev);
omap_gpio_dbck_disable(bank);
- raw_spin_unlock_irqrestore(&bank->lock, flags);
-
- return 0;
}
static void omap_gpio_init_context(struct gpio_bank *p);
-static int omap_gpio_runtime_resume(struct device *dev)
+static void omap_gpio_unidle(struct gpio_bank *bank)
{
- struct platform_device *pdev = to_platform_device(dev);
- struct gpio_bank *bank = platform_get_drvdata(pdev);
+ struct device *dev = bank->chip.parent;
u32 l = 0, gen, gen0, gen1;
- unsigned long flags;
int c;
- raw_spin_lock_irqsave(&bank->lock, flags);
-
/*
* On the first resume during the probe, the context has not
* been initialised and so initialise it now. Also initialise
@@ -1459,16 +1578,8 @@ static int omap_gpio_runtime_resume(struct device *dev)
omap_gpio_dbck_enable(bank);
- /*
- * In ->runtime_suspend(), level-triggered, wakeup-enabled
- * GPIOs were set to edge trigger also in order to be able to
- * generate a PRCM wakeup. Here we restore the
- * pre-runtime_suspend() values for edge triggering.
- */
- writel_relaxed(bank->context.fallingdetect,
- bank->base + bank->regs->fallingdetect);
- writel_relaxed(bank->context.risingdetect,
- bank->base + bank->regs->risingdetect);
+ if (bank->funcs.idle_disable_level_quirk)
+ bank->funcs.idle_disable_level_quirk(bank);
if (bank->loses_context) {
if (!bank->get_context_loss_count) {
@@ -1478,16 +1589,13 @@ static int omap_gpio_runtime_resume(struct device *dev)
if (c != bank->context_loss_count) {
omap_gpio_restore_context(bank);
} else {
- raw_spin_unlock_irqrestore(&bank->lock, flags);
- return 0;
+ return;
}
}
}
- if (!bank->workaround_enabled) {
- raw_spin_unlock_irqrestore(&bank->lock, flags);
- return 0;
- }
+ if (!bank->workaround_enabled)
+ return;
l = readl_relaxed(bank->base + bank->regs->datain);
@@ -1540,41 +1648,8 @@ static int omap_gpio_runtime_resume(struct device *dev)
}
bank->workaround_enabled = false;
- raw_spin_unlock_irqrestore(&bank->lock, flags);
-
- return 0;
-}
-#endif /* CONFIG_PM */
-
-#if IS_BUILTIN(CONFIG_GPIO_OMAP)
-void omap2_gpio_prepare_for_idle(int pwr_mode)
-{
- struct gpio_bank *bank;
-
- list_for_each_entry(bank, &omap_gpio_list, node) {
- if (!BANK_USED(bank) || !bank->loses_context)
- continue;
-
- bank->power_mode = pwr_mode;
-
- pm_runtime_put_sync_suspend(bank->chip.parent);
- }
-}
-
-void omap2_gpio_resume_after_idle(void)
-{
- struct gpio_bank *bank;
-
- list_for_each_entry(bank, &omap_gpio_list, node) {
- if (!BANK_USED(bank) || !bank->loses_context)
- continue;
-
- pm_runtime_get_sync(bank->chip.parent);
- }
}
-#endif
-#if defined(CONFIG_PM)
static void omap_gpio_init_context(struct gpio_bank *p)
{
struct omap_gpio_reg_offs *regs = p->regs;
@@ -1631,17 +1706,57 @@ static void omap_gpio_restore_context(struct gpio_bank *bank)
writel_relaxed(bank->context.irqenable2,
bank->base + bank->regs->irqenable2);
}
-#endif /* CONFIG_PM */
-#else
-#define omap_gpio_runtime_suspend NULL
-#define omap_gpio_runtime_resume NULL
-static inline void omap_gpio_init_context(struct gpio_bank *p) {}
-#endif
+static int __maybe_unused omap_gpio_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct gpio_bank *bank = platform_get_drvdata(pdev);
+ unsigned long flags;
+ int error = 0;
+
+ raw_spin_lock_irqsave(&bank->lock, flags);
+ /* Must be idled only by CPU_CLUSTER_PM_ENTER? */
+ if (bank->irq_usage) {
+ error = -EBUSY;
+ goto unlock;
+ }
+ omap_gpio_idle(bank, true);
+ bank->is_suspended = true;
+unlock:
+ raw_spin_unlock_irqrestore(&bank->lock, flags);
+
+ return error;
+}
+
+static int __maybe_unused omap_gpio_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct gpio_bank *bank = platform_get_drvdata(pdev);
+ unsigned long flags;
+ int error = 0;
+
+ raw_spin_lock_irqsave(&bank->lock, flags);
+ /* Must be unidled only by CPU_CLUSTER_PM_ENTER? */
+ if (bank->irq_usage) {
+ error = -EBUSY;
+ goto unlock;
+ }
+ omap_gpio_unidle(bank);
+ bank->is_suspended = false;
+unlock:
+ raw_spin_unlock_irqrestore(&bank->lock, flags);
+
+ return error;
+}
+
+#ifdef CONFIG_ARCH_OMAP2PLUS
static const struct dev_pm_ops gpio_pm_ops = {
SET_RUNTIME_PM_OPS(omap_gpio_runtime_suspend, omap_gpio_runtime_resume,
NULL)
};
+#else
+static const struct dev_pm_ops gpio_pm_ops;
+#endif /* CONFIG_ARCH_OMAP2PLUS */
#if defined(CONFIG_OF)
static struct omap_gpio_reg_offs omap2_gpio_regs = {
@@ -1690,6 +1805,11 @@ static struct omap_gpio_reg_offs omap4_gpio_regs = {
.fallingdetect = OMAP4_GPIO_FALLINGDETECT,
};
+/*
+ * Note that omap2 does not currently support idle modes with context loss so
+ * no need to add OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER quirk flag to save
+ * and restore context.
+ */
static const struct omap_gpio_platform_data omap2_pdata = {
.regs = &omap2_gpio_regs,
.bank_width = 32,
@@ -1700,12 +1820,15 @@ static const struct omap_gpio_platform_data omap3_pdata = {
.regs = &omap2_gpio_regs,
.bank_width = 32,
.dbck_flag = true,
+ .quirks = OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER,
};
static const struct omap_gpio_platform_data omap4_pdata = {
.regs = &omap4_gpio_regs,
.bank_width = 32,
.dbck_flag = true,
+ .quirks = OMAP_GPIO_QUIRK_IDLE_REMOVE_TRIGGER |
+ OMAP_GPIO_QUIRK_DEFERRED_WKUP_EN,
};
static const struct of_device_id omap_gpio_match[] = {
OpenPOWER on IntegriCloud