Skip to content

Commit

Permalink
MFD: ucb1x00: convert to use genirq
Browse files Browse the repository at this point in the history 
Convert the ucb1x00 driver to use genirq's interrupt services, rather
than its own private implementation.  This allows a wider range of
drivers to use the GPIO interrupts (such as the gpio_keys driver)
without being aware of the UCB1x00's private IRQ system.

This prevents the UCB1x00 core driver from being built as a module,
so adjust the configuration to add that restriction.

Acked-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
  • Loading branch information
Russell King committed Feb 18, 2012
1 parent cf4abfc commit a336440
Show file tree
Hide file tree
Showing 4 changed files with 132 additions and 179 deletions.
5 changes: 3 additions & 2 deletions drivers/mfd/Kconfig
View file
Original file line number Diff line number Diff line change
Expand Up @@ -847,8 +847,9 @@ config MCP_SA11X0

# Chip drivers
config MCP_UCB1200
tristate "Support for UCB1200 / UCB1300"
depends on MCP
bool "Support for UCB1200 / UCB1300"
depends on MCP_SA11X0
select MCP

config MCP_UCB1200_TS
tristate "Touchscreen interface support"
Expand Down
247 changes: 95 additions & 152 deletions drivers/mfd/ucb1x00-core.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -23,6 +23,7 @@
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/mfd/ucb1x00.h>
Expand Down Expand Up @@ -178,6 +179,13 @@ static int ucb1x00_gpio_direction_output(struct gpio_chip *chip, unsigned offset
return 0;
}

static int ucb1x00_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct ucb1x00 *ucb = container_of(chip, struct ucb1x00, gpio);

return ucb->irq_base > 0 ? ucb->irq_base + offset : -ENXIO;
}

/*
* UCB1300 data sheet says we must:
* 1. enable ADC => 5us (including reference startup time)
Expand Down Expand Up @@ -274,168 +282,94 @@ void ucb1x00_adc_disable(struct ucb1x00 *ucb)
* SIBCLK to talk to the chip. We leave the clock running until
* we have finished processing all interrupts from the chip.
*/
static irqreturn_t ucb1x00_irq(int irqnr, void *devid)
static void ucb1x00_irq(unsigned int irq, struct irq_desc *desc)
{
struct ucb1x00 *ucb = devid;
struct ucb1x00_irq *irq;
struct ucb1x00 *ucb = irq_desc_get_handler_data(desc);
unsigned int isr, i;

ucb1x00_enable(ucb);
isr = ucb1x00_reg_read(ucb, UCB_IE_STATUS);
ucb1x00_reg_write(ucb, UCB_IE_CLEAR, isr);
ucb1x00_reg_write(ucb, UCB_IE_CLEAR, 0);

for (i = 0, irq = ucb->irq_handler; i < 16 && isr; i++, isr >>= 1, irq++)
if (isr & 1 && irq->fn)
irq->fn(i, irq->devid);
for (i = 0; i < 16 && isr; i++, isr >>= 1, irq++)
if (isr & 1)
generic_handle_irq(ucb->irq_base + i);
ucb1x00_disable(ucb);

return IRQ_HANDLED;
}

/**
* ucb1x00_hook_irq - hook a UCB1x00 interrupt
* @ucb: UCB1x00 structure describing chip
* @idx: interrupt index
* @fn: function to call when interrupt is triggered
* @devid: device id to pass to interrupt handler
*
* Hook the specified interrupt. You can only register one handler
* for each interrupt source. The interrupt source is not enabled
* by this function; use ucb1x00_enable_irq instead.
*
* Interrupt handlers will be called with other interrupts enabled.
*
* Returns zero on success, or one of the following errors:
* -EINVAL if the interrupt index is invalid
* -EBUSY if the interrupt has already been hooked
*/
int ucb1x00_hook_irq(struct ucb1x00 *ucb, unsigned int idx, void (*fn)(int, void *), void *devid)
static void ucb1x00_irq_update(struct ucb1x00 *ucb, unsigned mask)
{
struct ucb1x00_irq *irq;
int ret = -EINVAL;

if (idx < 16) {
irq = ucb->irq_handler + idx;
ret = -EBUSY;

spin_lock_irq(&ucb->lock);
if (irq->fn == NULL) {
irq->devid = devid;
irq->fn = fn;
ret = 0;
}
spin_unlock_irq(&ucb->lock);
}
return ret;
ucb1x00_enable(ucb);
if (ucb->irq_ris_enbl & mask)
ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
ucb->irq_mask);
if (ucb->irq_fal_enbl & mask)
ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
ucb->irq_mask);
ucb1x00_disable(ucb);
}

/**
* ucb1x00_enable_irq - enable an UCB1x00 interrupt source
* @ucb: UCB1x00 structure describing chip
* @idx: interrupt index
* @edges: interrupt edges to enable
*
* Enable the specified interrupt to trigger on %UCB_RISING,
* %UCB_FALLING or both edges. The interrupt should have been
* hooked by ucb1x00_hook_irq.
*/
void ucb1x00_enable_irq(struct ucb1x00 *ucb, unsigned int idx, int edges)
static void ucb1x00_irq_noop(struct irq_data *data)
{
unsigned long flags;

if (idx < 16) {
spin_lock_irqsave(&ucb->lock, flags);

ucb1x00_enable(ucb);
if (edges & UCB_RISING) {
ucb->irq_ris_enbl |= 1 << idx;
ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
}
if (edges & UCB_FALLING) {
ucb->irq_fal_enbl |= 1 << idx;
ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
}
ucb1x00_disable(ucb);
spin_unlock_irqrestore(&ucb->lock, flags);
}
}

/**
* ucb1x00_disable_irq - disable an UCB1x00 interrupt source
* @ucb: UCB1x00 structure describing chip
* @edges: interrupt edges to disable
*
* Disable the specified interrupt triggering on the specified
* (%UCB_RISING, %UCB_FALLING or both) edges.
*/
void ucb1x00_disable_irq(struct ucb1x00 *ucb, unsigned int idx, int edges)
static void ucb1x00_irq_mask(struct irq_data *data)
{
unsigned long flags;
struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
unsigned mask = 1 << (data->irq - ucb->irq_base);

if (idx < 16) {
spin_lock_irqsave(&ucb->lock, flags);

ucb1x00_enable(ucb);
if (edges & UCB_RISING) {
ucb->irq_ris_enbl &= ~(1 << idx);
ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
}
if (edges & UCB_FALLING) {
ucb->irq_fal_enbl &= ~(1 << idx);
ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
}
ucb1x00_disable(ucb);
spin_unlock_irqrestore(&ucb->lock, flags);
}
raw_spin_lock(&ucb->irq_lock);
ucb->irq_mask &= ~mask;
ucb1x00_irq_update(ucb, mask);
raw_spin_unlock(&ucb->irq_lock);
}

/**
* ucb1x00_free_irq - disable and free the specified UCB1x00 interrupt
* @ucb: UCB1x00 structure describing chip
* @idx: interrupt index
* @devid: device id.
*
* Disable the interrupt source and remove the handler. devid must
* match the devid passed when hooking the interrupt.
*
* Returns zero on success, or one of the following errors:
* -EINVAL if the interrupt index is invalid
* -ENOENT if devid does not match
*/
int ucb1x00_free_irq(struct ucb1x00 *ucb, unsigned int idx, void *devid)
static void ucb1x00_irq_unmask(struct irq_data *data)
{
struct ucb1x00_irq *irq;
int ret;
struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
unsigned mask = 1 << (data->irq - ucb->irq_base);

if (idx >= 16)
goto bad;

irq = ucb->irq_handler + idx;
ret = -ENOENT;
raw_spin_lock(&ucb->irq_lock);
ucb->irq_mask |= mask;
ucb1x00_irq_update(ucb, mask);
raw_spin_unlock(&ucb->irq_lock);
}

spin_lock_irq(&ucb->lock);
if (irq->devid == devid) {
ucb->irq_ris_enbl &= ~(1 << idx);
ucb->irq_fal_enbl &= ~(1 << idx);
static int ucb1x00_irq_set_type(struct irq_data *data, unsigned int type)
{
struct ucb1x00 *ucb = irq_data_get_irq_chip_data(data);
unsigned mask = 1 << (data->irq - ucb->irq_base);

ucb1x00_enable(ucb);
ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl);
ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl);
ucb1x00_disable(ucb);
raw_spin_lock(&ucb->irq_lock);
if (type & IRQ_TYPE_EDGE_RISING)
ucb->irq_ris_enbl |= mask;
else
ucb->irq_ris_enbl &= ~mask;

irq->fn = NULL;
irq->devid = NULL;
ret = 0;
if (type & IRQ_TYPE_EDGE_FALLING)
ucb->irq_fal_enbl |= mask;
else
ucb->irq_fal_enbl &= ~mask;
if (ucb->irq_mask & mask) {
ucb1x00_reg_write(ucb, UCB_IE_RIS, ucb->irq_ris_enbl &
ucb->irq_mask);
ucb1x00_reg_write(ucb, UCB_IE_FAL, ucb->irq_fal_enbl &
ucb->irq_mask);
}
spin_unlock_irq(&ucb->lock);
return ret;
raw_spin_unlock(&ucb->irq_lock);

bad:
printk(KERN_ERR "Freeing bad UCB1x00 irq %d\n", idx);
return -EINVAL;
return 0;
}

static struct irq_chip ucb1x00_irqchip = {
.name = "ucb1x00",
.irq_ack = ucb1x00_irq_noop,
.irq_mask = ucb1x00_irq_mask,
.irq_unmask = ucb1x00_irq_unmask,
.irq_set_type = ucb1x00_irq_set_type,
};

static int ucb1x00_add_dev(struct ucb1x00 *ucb, struct ucb1x00_driver *drv)
{
struct ucb1x00_dev *dev;
Expand Down Expand Up @@ -545,9 +479,8 @@ static int ucb1x00_probe(struct mcp *mcp)
struct ucb1x00_plat_data *pdata = mcp->attached_device.platform_data;
struct ucb1x00_driver *drv;
struct ucb1x00 *ucb;
unsigned int id;
unsigned id, i, irq_base;
int ret = -ENODEV;
int temp;

/* Tell the platform to deassert the UCB1x00 reset */
if (pdata && pdata->reset)
Expand All @@ -572,7 +505,7 @@ static int ucb1x00_probe(struct mcp *mcp)
ucb->dev.parent = &mcp->attached_device;
dev_set_name(&ucb->dev, "ucb1x00");

spin_lock_init(&ucb->lock);
raw_spin_lock_init(&ucb->irq_lock);
spin_lock_init(&ucb->io_lock);
mutex_init(&ucb->adc_mutex);

Expand All @@ -593,6 +526,26 @@ static int ucb1x00_probe(struct mcp *mcp)
}

ucb->gpio.base = -1;
irq_base = pdata ? pdata->irq_base : 0;
ucb->irq_base = irq_alloc_descs(-1, irq_base, 16, -1);
if (ucb->irq_base < 0) {
dev_err(&ucb->dev, "unable to allocate 16 irqs: %d\n",
ucb->irq_base);
goto err_irq_alloc;
}

for (i = 0; i < 16; i++) {
unsigned irq = ucb->irq_base + i;

irq_set_chip_and_handler(irq, &ucb1x00_irqchip, handle_edge_irq);
irq_set_chip_data(irq, ucb);
set_irq_flags(irq, IRQF_VALID | IRQ_NOREQUEST);
}

irq_set_irq_type(ucb->irq, IRQ_TYPE_EDGE_RISING);
irq_set_handler_data(ucb->irq, ucb);
irq_set_chained_handler(ucb->irq, ucb1x00_irq);

if (pdata && pdata->gpio_base) {
ucb->gpio.label = dev_name(&ucb->dev);
ucb->gpio.dev = &ucb->dev;
Expand All @@ -603,20 +556,13 @@ static int ucb1x00_probe(struct mcp *mcp)
ucb->gpio.get = ucb1x00_gpio_get;
ucb->gpio.direction_input = ucb1x00_gpio_direction_input;
ucb->gpio.direction_output = ucb1x00_gpio_direction_output;
ucb->gpio.to_irq = ucb1x00_to_irq;
ret = gpiochip_add(&ucb->gpio);
if (ret)
goto err_gpio_add;
} else
dev_info(&ucb->dev, "gpio_base not set so no gpiolib support");

ret = request_irq(ucb->irq, ucb1x00_irq, IRQF_TRIGGER_RISING,
"UCB1x00", ucb);
if (ret) {
dev_err(&ucb->dev, "ucb1x00: unable to grab irq%d: %d\n",
ucb->irq, ret);
goto err_irq;
}

mcp_set_drvdata(mcp, ucb);

INIT_LIST_HEAD(&ucb->devs);
Expand All @@ -629,10 +575,11 @@ static int ucb1x00_probe(struct mcp *mcp)

return ret;

err_irq:
if (ucb->gpio.base != -1)
temp = gpiochip_remove(&ucb->gpio);
err_gpio_add:
irq_set_chained_handler(ucb->irq, NULL);
err_irq_alloc:
if (ucb->irq_base > 0)
irq_free_descs(ucb->irq_base, 16);
err_no_irq:
device_del(&ucb->dev);
err_dev_add:
Expand Down Expand Up @@ -664,7 +611,8 @@ static void ucb1x00_remove(struct mcp *mcp)
dev_err(&ucb->dev, "Can't remove gpio chip: %d\n", ret);
}

free_irq(ucb->irq, ucb);
irq_set_chained_handler(ucb->irq, NULL);
irq_free_descs(ucb->irq_base, 16);
device_unregister(&ucb->dev);

if (pdata && pdata->reset)
Expand Down Expand Up @@ -772,11 +720,6 @@ EXPORT_SYMBOL(ucb1x00_adc_enable);
EXPORT_SYMBOL(ucb1x00_adc_read);
EXPORT_SYMBOL(ucb1x00_adc_disable);

EXPORT_SYMBOL(ucb1x00_hook_irq);
EXPORT_SYMBOL(ucb1x00_free_irq);
EXPORT_SYMBOL(ucb1x00_enable_irq);
EXPORT_SYMBOL(ucb1x00_disable_irq);

EXPORT_SYMBOL(ucb1x00_register_driver);
EXPORT_SYMBOL(ucb1x00_unregister_driver);

Expand Down
Loading

0 comments on commit a336440

Please sign in to comment.