1 files changed, 22 insertions, 13 deletions

diff --git a/drivers/pinctrl/intel/pinctrl-baytrail.c b/drivers/pinctrl/intel/pinctrl-baytrail.c
index 5afe03e28b91..e44f2fd6753f 100644
--- a/drivers/pinctrl/intel/pinctrl-baytrail.c
+++ b/drivers/pinctrl/intel/pinctrl-baytrail.c
@@ -158,40 +158,49 @@ static void __iomem *byt_gpio_reg(struct gpio_chip *chip, unsigned offset,
         return vg->reg_base + reg_offset + reg;
 }
 
-static bool is_special_pin(struct byt_gpio *vg, unsigned offset)
+static u32 byt_get_gpio_mux(struct byt_gpio *vg, unsigned offset)
 {
         /* SCORE pin 92-93 */
         if (!strcmp(vg->range->name, BYT_SCORE_ACPI_UID) &&
                 offset >= 92 && offset <= 93)
-                return true;
+                return 1;
 
         /* SUS pin 11-21 */
         if (!strcmp(vg->range->name, BYT_SUS_ACPI_UID) &&
                 offset >= 11 && offset <= 21)
-                return true;
+                return 1;
 
-        return false;
+        return 0;
 }
 
 static int byt_gpio_request(struct gpio_chip *chip, unsigned offset)
 {
         struct byt_gpio *vg = to_byt_gpio(chip);
         void __iomem *reg = byt_gpio_reg(chip, offset, BYT_CONF0_REG);
-        u32 value;
-        bool special;
+        u32 value, gpio_mux;
 
         /*
          * In most cases, func pin mux 000 means GPIO function.
          * But, some pins may have func pin mux 001 represents
-         * GPIO function. Only allow user to export pin with
-         * func pin mux preset as GPIO function by BIOS/FW.
+         * GPIO function.
+         *
+         * Because there are devices out there where some pins were not
+         * configured correctly we allow changing the mux value from
+         * request (but print out warning about that).
          */
         value = readl(reg) & BYT_PIN_MUX;
-        special = is_special_pin(vg, offset);
-        if ((special && value != 1) || (!special && value)) {
-                dev_err(&vg->pdev->dev,
-                        "pin %u cannot be used as GPIO.\n", offset);
-                return -EINVAL;
+        gpio_mux = byt_get_gpio_mux(vg, offset);
+        if (WARN_ON(gpio_mux != value)) {
+                unsigned long flags;
+
+                spin_lock_irqsave(&vg->lock, flags);
+                value = readl(reg) & ~BYT_PIN_MUX;
+                value |= gpio_mux;
+                writel(value, reg);
+                spin_unlock_irqrestore(&vg->lock, flags);
+
+                dev_warn(&vg->pdev->dev,
+                         "pin %u forcibly re-configured as GPIO\n", offset);
         }
 
         pm_runtime_get(&vg->pdev->dev);