*/
#include <linux/module.h>
-#include <linux/kernel_stat.h>
#include <linux/init.h>
-#include <linux/time.h>
#include <linux/interrupt.h>
-#include <linux/device.h>
#include <linux/kthread.h>
#include <linux/irq.h>
#include <linux/gpio.h>
*/
-static inline void activate_irq(int irq)
-{
-#ifdef CONFIG_ARM
- /* ARM requires an extra step to clear IRQ_NOREQUEST, which it
- * sets on behalf of every irq_chip. Also sets IRQ_NOPROBE.
- */
- set_irq_flags(irq, IRQF_VALID);
-#else
- /* same effect on other architectures */
- set_irq_noprobe(irq);
-#endif
-}
-
static struct gpio_chip twl_gpiochip;
static int twl4030_gpio_irq_base;
-static int twl4030_gpio_irq_end;
/* genirq interfaces are not available to modules */
#ifdef MODULE
/* store usage of each GPIO. - each bit represents one GPIO */
static unsigned int gpio_usage_count;
-/* shadow the imr register */
-static unsigned int gpio_imr_shadow;
-
-/* bitmask of pending requests to unmask gpio interrupts */
-static unsigned int gpio_pending_unmask;
-
-/* bitmask of requests to set gpio irq trigger type */
-static unsigned int gpio_pending_trigger;
-
-/* pointer to gpio unmask thread struct */
-static struct task_struct *gpio_unmask_thread;
-
-/*
- * Helper functions to read and write the GPIO ISR and IMR registers as
- * 32-bit integers. Functions return 0 on success, non-zero otherwise.
- * The caller must hold gpio_lock.
- */
-
-static int gpio_read_isr(unsigned int *isr)
-{
- int ret;
-
- *isr = 0;
- ret = twl4030_i2c_read(TWL4030_MODULE_GPIO, (u8 *) isr,
- REG_GPIO_ISR1A, 3);
- le32_to_cpup(isr);
- *isr &= GPIO_32_MASK;
-
- return ret;
-}
-
-static int gpio_write_isr(unsigned int isr)
-{
- isr &= GPIO_32_MASK;
- /*
- * The buffer passed to the twl4030_i2c_write() routine must have an
- * extra byte at the beginning reserved for its internal use.
- */
- isr <<= 8;
- isr = cpu_to_le32(isr);
- return twl4030_i2c_write(TWL4030_MODULE_GPIO, (u8 *) &isr,
- REG_GPIO_ISR1A, 3);
-}
-
-static int gpio_write_imr(unsigned int imr)
-{
- imr &= GPIO_32_MASK;
- /*
- * The buffer passed to the twl4030_i2c_write() routine must have an
- * extra byte at the beginning reserved for its internal use.
- */
- imr <<= 8;
- imr = cpu_to_le32(imr);
- return twl4030_i2c_write(TWL4030_MODULE_GPIO, (u8 *) &imr,
- REG_GPIO_IMR1A, 3);
-}
-
-/*
- * These routines are analagous to the irqchip methods, but they are designed
- * to be called from thread context with cpu interrupts enabled and with no
- * locked spinlocks. We call these routines from our custom IRQ handler
- * instead of the usual irqchip methods.
- */
-static void twl4030_gpio_mask_and_ack(unsigned int irq)
-{
- int gpio = irq - twl4030_gpio_irq_base;
-
- mutex_lock(&gpio_lock);
- /* mask */
- gpio_imr_shadow |= (1 << gpio);
- gpio_write_imr(gpio_imr_shadow);
- /* ack */
- gpio_write_isr(1 << gpio);
- mutex_unlock(&gpio_lock);
-}
-
-static void twl4030_gpio_unmask(unsigned int irq)
-{
- int gpio = irq - twl4030_gpio_irq_base;
-
- mutex_lock(&gpio_lock);
- gpio_imr_shadow &= ~(1 << gpio);
- gpio_write_imr(gpio_imr_shadow);
- mutex_unlock(&gpio_lock);
-}
-
-/*
- * These are the irqchip methods for the TWL4030 GPIO interrupts.
- * Our IRQ handle method doesn't call these, but they will be called by
- * other routines such as setup_irq() and enable_irq(). They are called
- * with cpu interrupts disabled and with a lock on the irq_controller_lock
- * spinlock. This complicates matters, because accessing the TWL4030 GPIO
- * interrupt controller requires I2C bus transactions that can't be initiated
- * in this context. Our solution is to defer accessing the interrupt
- * controller to a kernel thread. We only need to support the unmask method.
- */
-
-static void twl4030_gpio_irq_mask_and_ack(unsigned int irq)
-{
-}
-
-static void twl4030_gpio_irq_mask(unsigned int irq)
-{
-}
-
-static void twl4030_gpio_irq_unmask(unsigned int irq)
-{
- int gpio = irq - twl4030_gpio_irq_base;
-
- gpio_pending_unmask |= (1 << gpio);
- if (gpio_unmask_thread && gpio_unmask_thread->state != TASK_RUNNING)
- wake_up_process(gpio_unmask_thread);
-}
-
-static int twl4030_gpio_irq_set_type(unsigned int irq, unsigned trigger)
-{
- struct irq_desc *desc = irq_desc + irq;
- int gpio = irq - twl4030_gpio_irq_base;
-
- trigger &= IRQ_TYPE_SENSE_MASK;
- if (trigger & ~IRQ_TYPE_EDGE_BOTH)
- return -EINVAL;
- if ((desc->status & IRQ_TYPE_SENSE_MASK) == trigger)
- return 0;
-
- desc->status &= ~IRQ_TYPE_SENSE_MASK;
- desc->status |= trigger;
-
- /* REVISIT This makes the "unmask" thread do double duty,
- * updating IRQ trigger modes too. Rename appropriately...
- */
- gpio_pending_trigger |= (1 << gpio);
- if (gpio_unmask_thread && gpio_unmask_thread->state != TASK_RUNNING)
- wake_up_process(gpio_unmask_thread);
-
- return 0;
-}
-
-static struct irq_chip twl4030_gpio_irq_chip = {
- .name = "twl4030",
- .ack = twl4030_gpio_irq_mask_and_ack,
- .mask = twl4030_gpio_irq_mask,
- .unmask = twl4030_gpio_irq_unmask,
- .set_type = twl4030_gpio_irq_set_type,
-};
-
+/*----------------------------------------------------------------------*/
/*
* To configure TWL4030 GPIO module registers
*/
int twl4030_request_gpio(int gpio)
{
- int ret = 0;
-
if (unlikely(gpio >= TWL4030_GPIO_MAX))
return -EPERM;
- ret = gpio_request(twl_gpiochip.base + gpio, NULL);
- if (ret < 0)
- return ret;
-
- mutex_lock(&gpio_lock);
- if (gpio_usage_count & BIT(gpio)) {
- ret = -EBUSY;
- } else {
- /* First time usage? - switch on GPIO module */
- if (!gpio_usage_count) {
- ret = gpio_twl4030_write(REG_GPIO_CTRL,
- MASK_GPIO_CTRL_GPIO_ON);
- ret = gpio_twl4030_write(REG_GPIO_SIH_CTRL, 0x00);
- }
- if (!ret)
- gpio_usage_count |= BIT(gpio);
- else
- gpio_free(twl_gpiochip.base + gpio);
- }
- mutex_unlock(&gpio_lock);
- return ret;
+ return gpio_request(twl_gpiochip.base + gpio, NULL);
}
EXPORT_SYMBOL(twl4030_request_gpio);
*/
int twl4030_free_gpio(int gpio)
{
- int ret = 0;
-
if (unlikely(gpio >= TWL4030_GPIO_MAX))
return -EPERM;
- mutex_lock(&gpio_lock);
-
- if ((gpio_usage_count & BIT(gpio)) == 0) {
- ret = -EPERM;
- } else {
- gpio_usage_count &= ~BIT(gpio);
- gpio_free(twl_gpiochip.base + gpio);
- }
-
- /* Last time usage? - switch off GPIO module */
- if (ret == 0 && !gpio_usage_count)
- ret = gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
-
- mutex_unlock(&gpio_lock);
- return ret;
+ gpio_free(twl_gpiochip.base + gpio);
+ return 0;
}
EXPORT_SYMBOL(twl4030_free_gpio);
}
EXPORT_SYMBOL(twl4030_get_gpio_datain);
-static int twl4030_set_gpio_edge_ctrl(int gpio, int edge)
-{
- u8 c_bnk = gpio >> 2;
- u8 c_off = (gpio & 0x3) * 2;
- u8 c_msk = 0;
- u8 reg = 0;
- u8 base = 0;
- int ret = 0;
-
- base = REG_GPIO_EDR1 + c_bnk;
-
- if (edge & IRQ_TYPE_EDGE_RISING)
- c_msk |= BIT(c_off + 1);
- if (edge & IRQ_TYPE_EDGE_FALLING)
- c_msk |= BIT(c_off);
-
- mutex_lock(&gpio_lock);
- ret = gpio_twl4030_read(base);
- if (ret >= 0) {
- /* clear the previous rising/falling values */
- reg = (u8) ret;
- reg &= ~(0x3 << c_off);
- reg |= c_msk;
- ret = gpio_twl4030_write(base, reg);
- }
- mutex_unlock(&gpio_lock);
- return ret;
-}
-
/*
* Configure debounce timing value for a GPIO pin on TWL4030
*/
}
#endif
-/* MODULE FUNCTIONS */
+/*----------------------------------------------------------------------*/
-/*
- * gpio_unmask_thread() runs as a kernel thread. It is awakened by the unmask
- * method for the GPIO interrupts. It unmasks all of the GPIO interrupts
- * specified in the gpio_pending_unmask bitmask. We have to do the unmasking
- * in a kernel thread rather than directly in the unmask method because of the
- * need to access the TWL4030 via the I2C bus. Note that we don't need to be
- * concerned about race conditions where the request to unmask a GPIO interrupt
- * has already been cancelled before this thread does the unmasking. If a GPIO
- * interrupt is improperly unmasked, then the IRQ handler for it will mask it
- * when an interrupt occurs.
- */
-static int twl4030_gpio_unmask_thread(void *data)
+static int twl_request(struct gpio_chip *chip, unsigned offset)
{
- current->flags |= PF_NOFREEZE;
-
- while (!kthread_should_stop()) {
- int irq;
- unsigned int gpio_unmask;
- unsigned int gpio_trigger;
-
- local_irq_disable();
- gpio_unmask = gpio_pending_unmask;
- gpio_pending_unmask = 0;
-
- gpio_trigger = gpio_pending_trigger;
- gpio_pending_trigger = 0;
- local_irq_enable();
-
- for (irq = twl4030_gpio_irq_base; 0 != gpio_unmask;
- gpio_unmask >>= 1, irq++) {
- if (gpio_unmask & 0x1)
- twl4030_gpio_unmask(irq);
- }
-
- for (irq = twl4030_gpio_irq_base;
- gpio_trigger;
- gpio_trigger >>= 1, irq++) {
- struct irq_desc *desc;
- unsigned type;
-
- if (!(gpio_trigger & 0x1))
- continue;
+ int status = 0;
- desc = irq_desc + irq;
- spin_lock_irq(&desc->lock);
- type = desc->status & IRQ_TYPE_SENSE_MASK;
- spin_unlock_irq(&desc->lock);
+ mutex_lock(&gpio_lock);
- twl4030_set_gpio_edge_ctrl(irq - twl4030_gpio_irq_base,
- type);
- }
+ /* on first use, turn GPIO module "on" */
+ if (!gpio_usage_count)
+ status = gpio_twl4030_write(REG_GPIO_CTRL,
+ MASK_GPIO_CTRL_GPIO_ON);
- local_irq_disable();
- if (!gpio_pending_unmask && !gpio_pending_trigger)
- set_current_state(TASK_INTERRUPTIBLE);
- local_irq_enable();
+ if (!status)
+ gpio_usage_count |= (0x1 << offset);
- schedule();
- }
- set_current_state(TASK_RUNNING);
- return 0;
+done:
+ mutex_unlock(&gpio_lock);
+ return status;
}
-/*
- * do_twl4030_gpio_irq() is the desc->handle method for each of the twl4030
- * gpio interrupts. It executes in kernel thread context.
- * On entry, cpu interrupts are enabled.
- */
-static void do_twl4030_gpio_irq(unsigned int irq, irq_desc_t *desc)
+static void twl_free(struct gpio_chip *chip, unsigned offset)
{
- struct irqaction *action;
- const unsigned int cpu = smp_processor_id();
-
- desc->status |= IRQ_LEVEL;
-
- /*
- * Acknowledge, clear _AND_ disable the interrupt.
- */
- twl4030_gpio_mask_and_ack(irq);
-
- if (!desc->depth) {
- kstat_cpu(cpu).irqs[irq]++;
-
- action = desc->action;
- if (action) {
- int ret;
- int status = 0;
- int retval = 0;
- do {
- /* Call the ISR with cpu interrupts enabled. */
- ret = action->handler(irq, action->dev_id);
- if (ret == IRQ_HANDLED)
- status |= action->flags;
- retval |= ret;
- action = action->next;
- } while (action);
-
- if (retval != IRQ_HANDLED)
- printk(KERN_ERR "ISR for TWL4030 GPIO"
- " irq %d can't handle interrupt\n",
- irq);
-
- if (!desc->depth)
- twl4030_gpio_unmask(irq);
- }
- }
-}
+ mutex_lock(&gpio_lock);
-/*
- * do_twl4030_gpio_module_irq() is the desc->handle method for the twl4030 gpio
- * module interrupt. It executes in kernel thread context.
- * This is a chained interrupt, so there is no desc->action method for it.
- * We query the gpio module interrupt controller in the twl4030 to determine
- * which gpio lines are generating interrupt requests, and then call the
- * desc->handle method for each gpio that needs service.
- * On entry, cpu interrupts are disabled.
- */
-static void do_twl4030_gpio_module_irq(unsigned int irq, irq_desc_t *desc)
-{
- const unsigned int cpu = smp_processor_id();
+ gpio_usage_count &= ~BIT(offset);
- desc->status |= IRQ_LEVEL;
- /*
- * The desc->handle method would normally call the desc->chip->ack
- * method here, but we won't bother since our ack method is NULL.
- */
- if (!desc->depth) {
- int gpio_irq;
- unsigned int gpio_isr;
-
- kstat_cpu(cpu).irqs[irq]++;
- local_irq_enable();
-
- mutex_lock(&gpio_lock);
- if (gpio_read_isr(&gpio_isr))
- gpio_isr = 0;
- mutex_unlock(&gpio_lock);
-
- for (gpio_irq = twl4030_gpio_irq_base; 0 != gpio_isr;
- gpio_isr >>= 1, gpio_irq++) {
- if (gpio_isr & 0x1) {
- irq_desc_t *d = irq_desc + gpio_irq;
- d->handle_irq(gpio_irq, d);
- }
- }
+ /* on last use, switch off GPIO module */
+ if (!gpio_usage_count)
+ gpio_twl4030_write(REG_GPIO_CTRL, 0x0);
- local_irq_disable();
- /*
- * Here is where we should call the unmask method, but again we
- * won't bother since it is NULL.
- */
- }
+ mutex_unlock(&gpio_lock);
}
-/*----------------------------------------------------------------------*/
-
static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
{
return twl4030_set_gpio_direction(offset, 1);
twl4030_set_gpio_dataout(offset, value);
}
+static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+ return twl4030_gpio_irq_base
+ ? (twl4030_gpio_irq_base + offset)
+ : -EINVAL;
+}
+
static struct gpio_chip twl_gpiochip = {
.label = "twl4030",
.owner = THIS_MODULE,
+ .request = twl_request,
+ .free = twl_free,
.direction_input = twl_direction_in,
.get = twl_get,
.direction_output = twl_direction_out,
.set = twl_set,
+ .to_irq = twl_to_irq,
.can_sleep = 1,
};
{
struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data;
int ret;
- int irq = 0;
-
- /* All GPIO interrupts are initially masked */
- gpio_pending_unmask = 0;
- gpio_imr_shadow = GPIO_32_MASK;
- ret = gpio_write_imr(gpio_imr_shadow);
-
- twl4030_gpio_irq_base = pdata->irq_base;
- twl4030_gpio_irq_end = pdata->irq_end;
- if ((twl4030_gpio_irq_end - twl4030_gpio_irq_base) > 0) {
+ /* maybe setup IRQs */
+ if (pdata->irq_base) {
if (is_module()) {
dev_err(&pdev->dev,
"can't dispatch IRQs from modules\n");
goto no_irqs;
}
- if (twl4030_gpio_irq_end > NR_IRQS) {
- dev_err(&pdev->dev,
- "last IRQ is too large: %d\n",
- twl4030_gpio_irq_end);
- return -EINVAL;
- }
- } else {
- dev_notice(&pdev->dev,
- "no IRQs being dispatched\n");
- goto no_irqs;
- }
-
- if (!ret) {
- /*
- * Create a kernel thread to handle deferred unmasking of gpio
- * interrupts.
- */
- gpio_unmask_thread = kthread_create(twl4030_gpio_unmask_thread,
- NULL, "twl4030 gpio");
- if (!gpio_unmask_thread) {
- dev_err(&pdev->dev,
- "could not create twl4030 gpio unmask"
- " thread!\n");
- ret = -ENOMEM;
- }
- }
-
- if (!ret) {
- /* install an irq handler for each of the gpio interrupts */
- for (irq = twl4030_gpio_irq_base; irq < twl4030_gpio_irq_end;
- irq++) {
- set_irq_chip_and_handler(irq, &twl4030_gpio_irq_chip,
- do_twl4030_gpio_irq);
- activate_irq(irq);
- }
-
- /* gpio module IRQ */
- irq = platform_get_irq(pdev, 0);
-
- /*
- * Install an irq handler to demultiplex the gpio module
- * interrupt.
- */
- set_irq_chained_handler(irq, do_twl4030_gpio_module_irq);
- wake_up_process(gpio_unmask_thread);
-
- dev_info(&pdev->dev, "IRQ %d chains IRQs %d..%d\n", irq,
- twl4030_gpio_irq_base, twl4030_gpio_irq_end - 1);
+ ret = twl4030_sih_setup(TWL4030_MODULE_GPIO);
+ if (ret < 0)
+ return ret;
+ WARN_ON(ret != pdata->irq_base);
+ twl4030_gpio_irq_base = ret;
}
no_irqs:
- if (!ret) {
- /*
- * NOTE: boards may waste power if they don't set pullups
- * and pulldowns correctly ... default for non-ULPI pins is
- * pulldown, and some other pins may have external pullups
- * or pulldowns. Careful!
- */
- ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns);
- if (ret)
- dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n",
- pdata->pullups, pdata->pulldowns,
- ret);
-
- twl_gpiochip.base = pdata->gpio_base;
- twl_gpiochip.ngpio = TWL4030_GPIO_MAX;
- twl_gpiochip.dev = &pdev->dev;
-
- ret = gpiochip_add(&twl_gpiochip);
- if (ret < 0) {
- dev_err(&pdev->dev,
- "could not register gpiochip, %d\n",
- ret);
- twl_gpiochip.ngpio = 0;
- gpio_twl4030_remove(pdev);
- } else if (pdata->setup) {
- int status;
-
- status = pdata->setup(&pdev->dev,
- pdata->gpio_base, TWL4030_GPIO_MAX);
- if (status)
- dev_dbg(&pdev->dev, "setup --> %d\n", status);
- }
+ /*
+ * NOTE: boards may waste power if they don't set pullups
+ * and pulldowns correctly ... default for non-ULPI pins is
+ * pulldown, and some other pins may have external pullups
+ * or pulldowns. Careful!
+ */
+ ret = gpio_twl4030_pulls(pdata->pullups, pdata->pulldowns);
+ if (ret)
+ dev_dbg(&pdev->dev, "pullups %.05x %.05x --> %d\n",
+ pdata->pullups, pdata->pulldowns,
+ ret);
+
+ twl_gpiochip.base = pdata->gpio_base;
+ twl_gpiochip.ngpio = TWL4030_GPIO_MAX;
+ twl_gpiochip.dev = &pdev->dev;
+
+ ret = gpiochip_add(&twl_gpiochip);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "could not register gpiochip, %d\n",
+ ret);
+ twl_gpiochip.ngpio = 0;
+ gpio_twl4030_remove(pdev);
+ } else if (pdata->setup) {
+ int status;
+
+ status = pdata->setup(&pdev->dev,
+ pdata->gpio_base, TWL4030_GPIO_MAX);
+ if (status)
+ dev_dbg(&pdev->dev, "setup --> %d\n", status);
}
return ret;
{
struct twl4030_gpio_platform_data *pdata = pdev->dev.platform_data;
int status;
- int irq;
if (pdata->teardown) {
status = pdata->teardown(&pdev->dev,
if (status < 0)
return status;
- if (is_module() || (twl4030_gpio_irq_end - twl4030_gpio_irq_base) <= 0)
+ if (is_module())
return 0;
- /* uninstall the gpio demultiplexing interrupt handler */
- irq = platform_get_irq(pdev, 0);
- set_irq_handler(irq, NULL);
-
- /* uninstall the irq handler for each of the gpio interrupts */
- for (irq = twl4030_gpio_irq_base; irq < twl4030_gpio_irq_end; irq++)
- set_irq_handler(irq, NULL);
-
- /* stop the gpio unmask kernel thread */
- if (gpio_unmask_thread) {
- kthread_stop(gpio_unmask_thread);
- gpio_unmask_thread = NULL;
- }
-
- return 0;
+ /* REVISIT no support yet for deregistering all the IRQs */
+ WARN_ON(1);
+ return -EIO;
}
/* Note: this hardware lives inside an I2C-based multi-function device. */
projects / linux-2.6-omap-h63xx.git / blobdiff