gpio/sx150x: Do not access I2C from mask/unmask functions

irq_chip->irq_mask/unmask are called with interrupts disabled and
irq_desc->lock held. So we cannot access i2c from this context. That's
what irq_bus_sync_unlock() is for.

Store the masked information in the chip data structure and update the
i2c bus from the irq_bus_sync_unlock() callback.

This does not need a while(pending) loop because the update to this is
always serialized via the bus lock, so we never have more than one pin
update pending.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Gregory Bean <gbean@codeaurora.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Lennert Buytenhek <buytenh@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Thomas Gleixner 2011-02-14 18:08:51 +01:00 committed by Grant Likely
parent 0b782531c0
commit 0ff56cd85a
1 changed files with 37 additions and 17 deletions

View File

@ -25,6 +25,8 @@
#include <linux/workqueue.h> #include <linux/workqueue.h>
#include <linux/i2c/sx150x.h> #include <linux/i2c/sx150x.h>
#define NO_UPDATE_PENDING -1
struct sx150x_device_data { struct sx150x_device_data {
u8 reg_pullup; u8 reg_pullup;
u8 reg_pulldn; u8 reg_pulldn;
@ -47,8 +49,11 @@ struct sx150x_chip {
const struct sx150x_device_data *dev_cfg; const struct sx150x_device_data *dev_cfg;
int irq_summary; int irq_summary;
int irq_base; int irq_base;
int irq_update;
u32 irq_sense; u32 irq_sense;
unsigned long irq_set_type_pending; u32 irq_masked;
u32 dev_sense;
u32 dev_masked;
struct irq_chip irq_chip; struct irq_chip irq_chip;
struct mutex lock; struct mutex lock;
}; };
@ -312,9 +317,8 @@ static void sx150x_irq_mask(struct irq_data *d)
chip = container_of(ic, struct sx150x_chip, irq_chip); chip = container_of(ic, struct sx150x_chip, irq_chip);
n = d->irq - chip->irq_base; n = d->irq - chip->irq_base;
chip->irq_masked |= (1 << n);
sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 1); chip->irq_update = n;
sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense, 0);
} }
static void sx150x_irq_unmask(struct irq_data *d) static void sx150x_irq_unmask(struct irq_data *d)
@ -326,9 +330,8 @@ static void sx150x_irq_unmask(struct irq_data *d)
chip = container_of(ic, struct sx150x_chip, irq_chip); chip = container_of(ic, struct sx150x_chip, irq_chip);
n = d->irq - chip->irq_base; n = d->irq - chip->irq_base;
sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 0); chip->irq_masked &= ~(1 << n);
sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense, chip->irq_update = n;
chip->irq_sense >> (n * 2));
} }
static int sx150x_irq_set_type(struct irq_data *d, unsigned int flow_type) static int sx150x_irq_set_type(struct irq_data *d, unsigned int flow_type)
@ -350,7 +353,7 @@ static int sx150x_irq_set_type(struct irq_data *d, unsigned int flow_type)
chip->irq_sense &= ~(3UL << (n * 2)); chip->irq_sense &= ~(3UL << (n * 2));
chip->irq_sense |= val << (n * 2); chip->irq_sense |= val << (n * 2);
chip->irq_set_type_pending |= BIT(n); chip->irq_update = n;
return 0; return 0;
} }
@ -404,15 +407,29 @@ static void sx150x_irq_bus_sync_unlock(struct irq_data *d)
chip = container_of(ic, struct sx150x_chip, irq_chip); chip = container_of(ic, struct sx150x_chip, irq_chip);
while (chip->irq_set_type_pending) { if (chip->irq_update == NO_UPDATE_PENDING)
n = __ffs(chip->irq_set_type_pending); goto out;
chip->irq_set_type_pending &= ~BIT(n);
if (!(irq_to_desc(n + chip->irq_base)->status & IRQ_MASKED)) n = chip->irq_update;
sx150x_write_cfg(chip, n, 2, chip->irq_update = NO_UPDATE_PENDING;
chip->dev_cfg->reg_sense,
/* Avoid updates if nothing changed */
if (chip->dev_sense == chip->irq_sense &&
chip->dev_sense == chip->irq_masked)
goto out;
chip->dev_sense = chip->irq_sense;
chip->dev_masked = chip->irq_masked;
if (chip->irq_masked & (1 << n)) {
sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 1);
sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense, 0);
} else {
sx150x_write_cfg(chip, n, 1, chip->dev_cfg->reg_irq_mask, 0);
sx150x_write_cfg(chip, n, 2, chip->dev_cfg->reg_sense,
chip->irq_sense >> (n * 2)); chip->irq_sense >> (n * 2));
} }
out:
mutex_unlock(&chip->lock); mutex_unlock(&chip->lock);
} }
@ -445,8 +462,11 @@ static void sx150x_init_chip(struct sx150x_chip *chip,
chip->irq_chip.irq_bus_sync_unlock = sx150x_irq_bus_sync_unlock; chip->irq_chip.irq_bus_sync_unlock = sx150x_irq_bus_sync_unlock;
chip->irq_summary = -1; chip->irq_summary = -1;
chip->irq_base = -1; chip->irq_base = -1;
chip->irq_masked = ~0;
chip->irq_sense = 0; chip->irq_sense = 0;
chip->irq_set_type_pending = 0; chip->dev_masked = ~0;
chip->dev_sense = 0;
chip->irq_update = NO_UPDATE_PENDING;
} }
static int sx150x_init_io(struct sx150x_chip *chip, u8 base, u16 cfg) static int sx150x_init_io(struct sx150x_chip *chip, u8 base, u16 cfg)