sh-pfc: Skip gpiochip registration when no GPIO resource is found

Boards/platforms that register dedicated GPIO devices will not supply a
memory resource for GPIOs. Try to locate the GPIO memory resource at
initialization time, and skip registration of the gpiochip if the
resource can't be found.

This is a temporary modification to ease the transition to separate GPIO
drivers. It should be reverted when all boards and platforms will have
been moved.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

1 files changed, 21 insertions, 18 deletions

diff --git a/drivers/pinctrl/sh-pfc/gpio.c b/drivers/pinctrl/sh-pfc/gpio.c
index 317cebb0ee4d..d37efa7dcf90 100644
--- a/drivers/pinctrl/sh-pfc/gpio.c
+++ b/drivers/pinctrl/sh-pfc/gpio.c
@@ -101,24 +101,9 @@ static void gpio_setup_data_reg(struct sh_pfc_chip *chip, unsigned gpio)
 static int gpio_setup_data_regs(struct sh_pfc_chip *chip)
 {
         struct sh_pfc *pfc = chip->pfc;
-        unsigned long addr = pfc->info->data_regs[0].reg;
         const struct pinmux_data_reg *dreg;
         unsigned int i;
 
-        /* Find the window that contain the GPIO registers. */
-        for (i = 0; i < pfc->num_windows; ++i) {
-                struct sh_pfc_window *window = &pfc->window[i];
-
-                if (addr >= window->phys && addr < window->phys + window->size)
-                        break;
-        }
-
-        if (i == pfc->num_windows)
-                return -EINVAL;
-
-        /* GPIO data registers must be in the first memory resource. */
-        chip->mem = &pfc->window[i];
-
         /* Count the number of data registers, allocate memory and initialize
          * them.
          */
@@ -319,7 +304,8 @@ static int gpio_function_setup(struct sh_pfc_chip *chip)
  */
 
 static struct sh_pfc_chip *
-sh_pfc_add_gpiochip(struct sh_pfc *pfc, int(*setup)(struct sh_pfc_chip *))
+sh_pfc_add_gpiochip(struct sh_pfc *pfc, int(*setup)(struct sh_pfc_chip *),
+                    struct sh_pfc_window *mem)
 {
         struct sh_pfc_chip *chip;
         int ret;
@@ -328,6 +314,7 @@ sh_pfc_add_gpiochip(struct sh_pfc *pfc, int(*setup)(struct sh_pfc_chip *))
         if (unlikely(!chip))
                 return ERR_PTR(-ENOMEM);
 
+        chip->mem = mem;
         chip->pfc = pfc;
 
         ret = setup(chip);
@@ -357,8 +344,24 @@ int sh_pfc_register_gpiochip(struct sh_pfc *pfc)
         if (pfc->info->data_regs == NULL)
                 return 0;
 
+        /* Find the memory window that contain the GPIO registers. Boards that
+         * register a separate GPIO device will not supply a memory resource
+         * that covers the data registers. In that case don't try to handle
+         * GPIOs.
+         */
+        for (i = 0; i < pfc->num_windows; ++i) {
+                struct sh_pfc_window *window = &pfc->window[i];
+
+                if (pfc->info->data_regs[0].reg >= window->phys &&
+                    pfc->info->data_regs[0].reg < window->phys + window->size)
+                        break;
+        }
+
+        if (i == pfc->num_windows)
+                return 0;
+
         /* Register the real GPIOs chip. */
-        chip = sh_pfc_add_gpiochip(pfc, gpio_pin_setup);
+        chip = sh_pfc_add_gpiochip(pfc, gpio_pin_setup, &pfc->window[i]);
         if (IS_ERR(chip))
                 return PTR_ERR(chip);
 
@@ -390,7 +393,7 @@ int sh_pfc_register_gpiochip(struct sh_pfc *pfc)
         if (pfc->info->nr_func_gpios == 0)
                 return 0;
 
-        chip = sh_pfc_add_gpiochip(pfc, gpio_function_setup);
+        chip = sh_pfc_add_gpiochip(pfc, gpio_function_setup, NULL);
         if (IS_ERR(chip))
                 return PTR_ERR(chip);