pinctrl: stm32: Add get_pins_count() ops

Add get_pins_count ops to obtain the number of pins
owns by a pin-controller.
On STM32 SoCs bindings, each pin-controller owns
several gpio banks. Each GPIO bank can own up to 16 pins.

To obtain the total pins count, walk through each sub-nodes
(ie GPIO banks) and sum each GPIO banks pins number. For that
in probe() we build a list with each GPIO device reference found.
This list will also be used with future get_pin_muxing and get_pin_name
ops to speed up and optimize walk through all GPIO banks.

As this code is common to all STM32 SoCs, this code is put
under SPL_BUILD compilation flag to avoid to increase SPL code size
for STM32F7 which is limited to 32Ko.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/pinctrl/pinctrl_stm32.c b/drivers/pinctrl/pinctrl_stm32.c
index 31285cdd5784da2f915f52a5fd2fe4c41079d067..27ee2a4bffdbc1d5db63d3e5a2d6b0531c99d574 100644 (file)
--- a/drivers/pinctrl/pinctrl_stm32.c
+++ b/drivers/pinctrl/pinctrl_stm32.c
@@ -14,6 +14,79 @@ DECLARE_GLOBAL_DATA_PTR;
 #define OTYPE_MSK                      1
 #define AFR_MASK                       0xF
 
+#ifndef CONFIG_SPL_BUILD
+struct stm32_pinctrl_priv {
+       int pinctrl_ngpios;
+       struct list_head gpio_dev;
+};
+
+struct stm32_gpio_bank {
+       struct udevice *gpio_dev;
+       struct list_head list;
+};
+
+static int stm32_pinctrl_get_pins_count(struct udevice *dev)
+{
+       struct stm32_pinctrl_priv *priv = dev_get_priv(dev);
+       struct gpio_dev_priv *uc_priv;
+       struct stm32_gpio_bank *gpio_bank;
+
+       /*
+        * if get_pins_count has already been executed once on this
+        * pin-controller, no need to run it again
+        */
+       if (priv->pinctrl_ngpios)
+               return priv->pinctrl_ngpios;
+
+       /*
+        * walk through all banks to retrieve the pin-controller
+        * pins number
+        */
+       list_for_each_entry(gpio_bank, &priv->gpio_dev, list) {
+               uc_priv = dev_get_uclass_priv(gpio_bank->gpio_dev);
+
+               priv->pinctrl_ngpios += uc_priv->gpio_count;
+       }
+
+       return priv->pinctrl_ngpios;
+}
+
+int stm32_pinctrl_probe(struct udevice *dev)
+{
+       struct stm32_pinctrl_priv *priv = dev_get_priv(dev);
+       struct udevice *gpio_dev;
+       struct udevice *child;
+       struct stm32_gpio_bank *gpio_bank;
+       int ret;
+
+       INIT_LIST_HEAD(&priv->gpio_dev);
+
+       /*
+        * parse pin-controller sub-nodes (ie gpio bank nodes) and fill
+        * a list with all gpio device reference which belongs to the
+        * current pin-controller. This list is used to find pin_name and
+        * pin muxing
+        */
+       list_for_each_entry(child, &dev->child_head, sibling_node) {
+               ret = uclass_get_device_by_name(UCLASS_GPIO, child->name,
+                                               &gpio_dev);
+               if (ret < 0)
+                       continue;
+
+               gpio_bank = malloc(sizeof(*gpio_bank));
+               if (!gpio_bank) {
+                       dev_err(dev, "Not enough memory\n");
+                       return -ENOMEM;
+               }
+
+               gpio_bank->gpio_dev = gpio_dev;
+               list_add_tail(&gpio_bank->list, &priv->gpio_dev);
+       }
+
+       return 0;
+}
+#endif
+
 static int stm32_gpio_config(struct gpio_desc *desc,
                             const struct stm32_gpio_ctl *ctl)
 {
@@ -182,6 +255,9 @@ static struct pinctrl_ops stm32_pinctrl_ops = {
 #else /* PINCTRL_FULL */
        .set_state_simple       = stm32_pinctrl_set_state_simple,
 #endif /* PINCTRL_FULL */
+#ifndef CONFIG_SPL_BUILD
+       .get_pins_count         = stm32_pinctrl_get_pins_count,
+#endif
 };
 
 static const struct udevice_id stm32_pinctrl_ids[] = {
@@ -195,9 +271,13 @@ static const struct udevice_id stm32_pinctrl_ids[] = {
 };
 
 U_BOOT_DRIVER(pinctrl_stm32) = {
-       .name           = "pinctrl_stm32",
-       .id             = UCLASS_PINCTRL,
-       .of_match       = stm32_pinctrl_ids,
-       .ops            = &stm32_pinctrl_ops,
-       .bind           = dm_scan_fdt_dev,
+       .name                   = "pinctrl_stm32",
+       .id                     = UCLASS_PINCTRL,
+       .of_match               = stm32_pinctrl_ids,
+       .ops                    = &stm32_pinctrl_ops,
+       .bind                   = dm_scan_fdt_dev,
+#ifndef CONFIG_SPL_BUILD
+       .probe                  = stm32_pinctrl_probe,
+       .priv_auto_alloc_size   = sizeof(struct stm32_pinctrl_priv),
+#endif
 };