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

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>

1 files changed, 20 insertions, 4 deletions

diff --git a/drivers/gpio/gpio-adp5588.c b/drivers/gpio/gpio-adp5588.c
index 3530ccd17e04..da9781a2ef4a 100644
--- 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;
 }