Currently after configuring a GPIO pin as an interrupt related pinmux registers are changed, but there is no protection from calling gpio_direction_*() in a badly written driver, which would cause the same pinmux register to be reconfigured for regular input/output and this disabling interrupt capability of the pin.
This patch addresses this issue by moving pinmux reconfiguration to .irq_startup() callback of irq_chip and calling gpio_lock_as_irq() helper to prevent reconfiguration of pin direction. Signed-off-by: Tomasz Figa <[email protected]> --- drivers/pinctrl/pinctrl-exynos.c | 69 +++++++++++++++++++++++++++++++++++---- drivers/pinctrl/pinctrl-samsung.h | 1 + 2 files changed, 64 insertions(+), 6 deletions(-) diff --git a/drivers/pinctrl/pinctrl-exynos.c b/drivers/pinctrl/pinctrl-exynos.c index 003bfd8..a209cb4 100644 --- a/drivers/pinctrl/pinctrl-exynos.c +++ b/drivers/pinctrl/pinctrl-exynos.c @@ -127,14 +127,10 @@ static int exynos_irq_set_type(struct irq_data *irqd, unsigned int type) struct irq_chip *chip = irq_data_get_irq_chip(irqd); struct exynos_irq_chip *our_chip = to_exynos_irq_chip(chip); struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(irqd); - struct samsung_pin_bank_type *bank_type = bank->type; struct samsung_pinctrl_drv_data *d = bank->drvdata; - unsigned int pin = irqd->hwirq; - unsigned int shift = EXYNOS_EINT_CON_LEN * pin; + unsigned int shift = EXYNOS_EINT_CON_LEN * irqd->hwirq; unsigned int con, trig_type; unsigned long reg_con = our_chip->eint_con + bank->eint_offset; - unsigned long flags; - unsigned int mask; switch (type) { case IRQ_TYPE_EDGE_RISING: @@ -167,8 +163,32 @@ static int exynos_irq_set_type(struct irq_data *irqd, unsigned int type) con |= trig_type << shift; writel(con, d->virt_base + reg_con); + return 0; +} + +static unsigned int exynos_irq_startup(struct irq_data *irqd) +{ + struct irq_chip *chip = irq_data_get_irq_chip(irqd); + struct exynos_irq_chip *our_chip = to_exynos_irq_chip(chip); + struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(irqd); + struct samsung_pin_bank_type *bank_type = bank->type; + struct samsung_pinctrl_drv_data *d = bank->drvdata; + unsigned int shift = EXYNOS_EINT_CON_LEN * irqd->hwirq; + unsigned long reg_con = our_chip->eint_con + bank->eint_offset; + unsigned long flags; + unsigned int mask; + unsigned int con; + int ret; + + ret = gpio_lock_as_irq(&bank->gpio_chip, irqd->hwirq); + if (ret) { + dev_err(bank->gpio_chip.dev, "unable to lock pin %s-%lu IRQ\n", + bank->name, irqd->hwirq); + return ret; + } + reg_con = bank->pctl_offset + bank_type->reg_offset[PINCFG_TYPE_FUNC]; - shift = pin * bank_type->fld_width[PINCFG_TYPE_FUNC]; + shift = irqd->hwirq * bank_type->fld_width[PINCFG_TYPE_FUNC]; mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1; spin_lock_irqsave(&bank->slock, flags); @@ -180,9 +200,42 @@ static int exynos_irq_set_type(struct irq_data *irqd, unsigned int type) spin_unlock_irqrestore(&bank->slock, flags); + exynos_irq_unmask(irqd); + return 0; } +static void exynos_irq_shutdown(struct irq_data *irqd) +{ + struct irq_chip *chip = irq_data_get_irq_chip(irqd); + struct exynos_irq_chip *our_chip = to_exynos_irq_chip(chip); + struct samsung_pin_bank *bank = irq_data_get_irq_chip_data(irqd); + struct samsung_pin_bank_type *bank_type = bank->type; + struct samsung_pinctrl_drv_data *d = bank->drvdata; + unsigned int shift = EXYNOS_EINT_CON_LEN * irqd->hwirq; + unsigned long reg_con = our_chip->eint_con + bank->eint_offset; + unsigned long flags; + unsigned int mask; + unsigned int con; + + reg_con = bank->pctl_offset + bank_type->reg_offset[PINCFG_TYPE_FUNC]; + shift = irqd->hwirq * bank_type->fld_width[PINCFG_TYPE_FUNC]; + mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1; + + exynos_irq_mask(irqd); + + spin_lock_irqsave(&bank->slock, flags); + + con = readl(d->virt_base + reg_con); + con &= ~(mask << shift); + con |= FUNC_INPUT << shift; + writel(con, d->virt_base + reg_con); + + spin_unlock_irqrestore(&bank->slock, flags); + + gpio_unlock_as_irq(&bank->gpio_chip, irqd->hwirq); +} + /* * irq_chip for gpio interrupts. */ @@ -193,6 +246,8 @@ static struct exynos_irq_chip exynos_gpio_irq_chip = { .irq_mask = exynos_irq_mask, .irq_ack = exynos_irq_ack, .irq_set_type = exynos_irq_set_type, + .irq_startup = exynos_irq_startup, + .irq_shutdown = exynos_irq_shutdown, }, .eint_con = EXYNOS_GPIO_ECON_OFFSET, .eint_mask = EXYNOS_GPIO_EMASK_OFFSET, @@ -336,6 +391,8 @@ static struct exynos_irq_chip exynos_wkup_irq_chip = { .irq_ack = exynos_irq_ack, .irq_set_type = exynos_irq_set_type, .irq_set_wake = exynos_wkup_irq_set_wake, + .irq_startup = exynos_irq_startup, + .irq_shutdown = exynos_irq_shutdown, }, .eint_con = EXYNOS_WKUP_ECON_OFFSET, .eint_mask = EXYNOS_WKUP_EMASK_OFFSET, diff --git a/drivers/pinctrl/pinctrl-samsung.h b/drivers/pinctrl/pinctrl-samsung.h index e2dce47..4d7566a 100644 --- a/drivers/pinctrl/pinctrl-samsung.h +++ b/drivers/pinctrl/pinctrl-samsung.h @@ -26,6 +26,7 @@ #include <linux/gpio.h> /* pinmux function number for pin as gpio output line */ +#define FUNC_INPUT 0x0 #define FUNC_OUTPUT 0x1 /** -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
