gpio: adp5588: Fix sleep-in-atomic-context bug

[ Upstream commit 6537886cdc9a637711fd6da980dbb87c2c87c9aa ]

This fixes:
[BUG] gpio: gpio-adp5588: A possible sleep-in-atomic-context bug
                          in adp5588_gpio_write()
[BUG] gpio: gpio-adp5588: A possible sleep-in-atomic-context bug
                          in adp5588_gpio_direction_input()

Reported-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpio/gpio-adp5588.c b/drivers/gpio/gpio-adp5588.c
index e717f8d..202d367 100644 (file)
--- a/drivers/gpio/gpio-adp5588.c
+++ b/drivers/gpio/gpio-adp5588.c
@@ -41,6 +41,8 @@ struct adp5588_gpio {
        uint8_t int_en[3];
        uint8_t irq_mask[3];
        uint8_t irq_stat[3];
+       uint8_t int_input_en[3];
+       uint8_t int_lvl_cached[3];
 };
 
 static int adp5588_gpio_read(struct i2c_client *client, u8 reg)
@@ -173,12 +175,28 @@ static void adp5588_irq_bus_sync_unlock(struct irq_data *d)
        struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d);
        int i;
 
-       for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++)
+       for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
+               if (dev->int_input_en[i]) {
+                       mutex_lock(&dev->lock);
+                       dev->dir[i] &= ~dev->int_input_en[i];
+                       dev->int_input_en[i] = 0;
+                       adp5588_gpio_write(dev->client, GPIO_DIR1 + i,
+                                          dev->dir[i]);
+                       mutex_unlock(&dev->lock);
+               }
+
+               if (dev->int_lvl_cached[i] != dev->int_lvl[i]) {
+                       dev->int_lvl_cached[i] = dev->int_lvl[i];
+                       adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + i,
+                                          dev->int_lvl[i]);
+               }
+
                if (dev->int_en[i] ^ dev->irq_mask[i]) {
                        dev->int_en[i] = dev->irq_mask[i];
                        adp5588_gpio_write(dev->client, GPIO_INT_EN1 + i,
                                           dev->int_en[i]);
                }
+       }
 
        mutex_unlock(&dev->irq_lock);
 }
@@ -221,9 +239,7 @@ static int adp5588_irq_set_type(struct irq_data *d, unsigned int type)
        else
                return -EINVAL;
 
-       adp5588_gpio_direction_input(&dev->gpio_chip, gpio);
-       adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + bank,
-                          dev->int_lvl[bank]);
+       dev->int_input_en[bank] |= bit;
 
        return 0;
 }