Commit 0ff56cd8 authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Grant Likely
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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: default avatarThomas 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: default avatarGrant Likely <grant.likely@secretlab.ca>
parent 0b782531

drivers/gpio/sx150x.c

+37 −17
Original line number Diff line number Diff line
@@ -25,6 +25,8 @@ 
#include <linux/workqueue.h>

#include <linux/i2c/sx150x.h>



#define NO_UPDATE_PENDING	-1



struct sx150x_device_data {

	u8 reg_pullup;

	u8 reg_pulldn;
@@ -47,8 +49,11 @@ struct sx150x_chip { 
	const struct sx150x_device_data *dev_cfg;

	int                              irq_summary;

	int                              irq_base;

	int				 irq_update;

	u32                              irq_sense;

	unsigned long                    irq_set_type_pending;

	u32				 irq_masked;

	u32				 dev_sense;

	u32				 dev_masked;

	struct irq_chip                  irq_chip;

	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);

	n = d->irq - chip->irq_base;



	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);

	chip->irq_masked |= (1 << n);

	chip->irq_update = n;

}



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);

	n = d->irq - chip->irq_base;



	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_masked &= ~(1 << n);

	chip->irq_update = n;

}



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 |= val << (n * 2);

	chip->irq_set_type_pending |= BIT(n);

	chip->irq_update = n;

	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);



	while (chip->irq_set_type_pending) {

		n = __ffs(chip->irq_set_type_pending);

		chip->irq_set_type_pending &= ~BIT(n);

		if (!(irq_to_desc(n + chip->irq_base)->status & IRQ_MASKED))

			sx150x_write_cfg(chip, n, 2,

					chip->dev_cfg->reg_sense,

	if (chip->irq_update == NO_UPDATE_PENDING)

		goto out;



	n = chip->irq_update;

	chip->irq_update = NO_UPDATE_PENDING;



	/* 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));

	}



out:

	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_summary                  = -1;

	chip->irq_base                     = -1;

	chip->irq_masked                   = ~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)

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