commit dbf928dd2634a682e6d549e6dd61e3f2a0e5db90
author Patrice Chotard <patrice.chotard@st.com> Mon Dec 03 10:52:51 2018 +0100
committer Tom Rini <trini@konsulko.com> Fri Dec 07 08:13:47 2018 -0500
tree ed7c1475dc616518f772d148f3e8bc762f4f7c61
parent 043550415b09c6ffd2d9c0af28cc977bfae9f166

gpio: stm32f7: Add gpio bank holes management

In some STM32 SoC packages, GPIO bank has not always 16 gpios.
Several cases can occur, gpio hole can be located at the beginning,
middle or end of the gpio bank or a combination of these 3
configurations.

For that, gpio bindings offer the gpio-ranges DT property which
described the gpio bank mapping.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>

drivers/gpio/stm32f7_gpio.c

diff --git a/drivers/gpio/stm32f7_gpio.c b/drivers/gpio/stm32f7_gpio.c
index a690c43..55553c9 100644
--- a/drivers/gpio/stm32f7_gpio.c
+++ b/drivers/gpio/stm32f7_gpio.c
@@ -20,12 +20,41 @@
 #define MODE_BITS_MASK			3
 #define BSRR_BIT(gpio_pin, value)	BIT(gpio_pin + (value ? 0 : 16))
 
+/*
+ * convert gpio offset to gpio index taking into account gpio holes
+ * into gpio bank
+ */
+int stm32_offset_to_index(struct udevice *dev, unsigned int offset)
+{
+	struct stm32_gpio_priv *priv = dev_get_priv(dev);
+	int idx = 0;
+	int i;
+
+	for (i = 0; i < STM32_GPIOS_PER_BANK; i++) {
+		if (priv->gpio_range & BIT(i)) {
+			if (idx == offset)
+				return idx;
+			idx++;
+		}
+	}
+	/* shouldn't happen */
+	return -EINVAL;
+}
+
 static int stm32_gpio_direction_input(struct udevice *dev, unsigned offset)
 {
 	struct stm32_gpio_priv *priv = dev_get_priv(dev);
 	struct stm32_gpio_regs *regs = priv->regs;
-	int bits_index = MODE_BITS(offset);
-	int mask = MODE_BITS_MASK << bits_index;
+	int bits_index;
+	int mask;
+	int idx;
+
+	idx = stm32_offset_to_index(dev, offset);
+	if (idx < 0)
+		return idx;
+
+	bits_index = MODE_BITS(idx);
+	mask = MODE_BITS_MASK << bits_index;
 
 	clrsetbits_le32(&regs->moder, mask, STM32_GPIO_MODE_IN << bits_index);
 
@@ -37,12 +66,20 @@
 {
 	struct stm32_gpio_priv *priv = dev_get_priv(dev);
 	struct stm32_gpio_regs *regs = priv->regs;
-	int bits_index = MODE_BITS(offset);
-	int mask = MODE_BITS_MASK << bits_index;
+	int bits_index;
+	int mask;
+	int idx;
+
+	idx = stm32_offset_to_index(dev, offset);
+	if (idx < 0)
+		return idx;
+
+	bits_index = MODE_BITS(idx);
+	mask = MODE_BITS_MASK << bits_index;
 
 	clrsetbits_le32(&regs->moder, mask, STM32_GPIO_MODE_OUT << bits_index);
 
-	writel(BSRR_BIT(offset, value), &regs->bsrr);
+	writel(BSRR_BIT(idx, value), &regs->bsrr);
 
 	return 0;
 }
@@ -51,16 +88,26 @@
 {
 	struct stm32_gpio_priv *priv = dev_get_priv(dev);
 	struct stm32_gpio_regs *regs = priv->regs;
+	int idx;
 
-	return readl(&regs->idr) & BIT(offset) ? 1 : 0;
+	idx = stm32_offset_to_index(dev, offset);
+	if (idx < 0)
+		return idx;
+
+	return readl(&regs->idr) & BIT(idx) ? 1 : 0;
 }
 
 static int stm32_gpio_set_value(struct udevice *dev, unsigned offset, int value)
 {
 	struct stm32_gpio_priv *priv = dev_get_priv(dev);
 	struct stm32_gpio_regs *regs = priv->regs;
+	int idx;
 
-	writel(BSRR_BIT(offset, value), &regs->bsrr);
+	idx = stm32_offset_to_index(dev, offset);
+	if (idx < 0)
+		return idx;
+
+	writel(BSRR_BIT(idx, value), &regs->bsrr);
 
 	return 0;
 }
@@ -69,10 +116,18 @@
 {
 	struct stm32_gpio_priv *priv = dev_get_priv(dev);
 	struct stm32_gpio_regs *regs = priv->regs;
-	int bits_index = MODE_BITS(offset);
-	int mask = MODE_BITS_MASK << bits_index;
+	int bits_index;
+	int mask;
+	int idx;
 	u32 mode;
 
+	idx = stm32_offset_to_index(dev, offset);
+	if (idx < 0)
+		return idx;
+
+	bits_index = MODE_BITS(idx);
+	mask = MODE_BITS_MASK << bits_index;
+
 	mode = (readl(&regs->moder) & mask) >> bits_index;
 	if (mode == STM32_GPIO_MODE_OUT)
 		return GPIOF_OUTPUT;
@@ -96,8 +151,11 @@
 {
 	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
 	struct stm32_gpio_priv *priv = dev_get_priv(dev);
+	struct ofnode_phandle_args args;
 	fdt_addr_t addr;
 	const char *name;
+	int ret;
+	int i;
 
 	addr = dev_read_addr(dev);
 	if (addr == FDT_ADDR_T_NONE)
@@ -108,14 +166,27 @@
 	if (!name)
 		return -EINVAL;
 	uc_priv->bank_name = name;
-	uc_priv->gpio_count = dev_read_u32_default(dev, "ngpios",
-						   STM32_GPIOS_PER_BANK);
-	debug("%s, addr = 0x%p, bank_name = %s\n", __func__, (u32 *)priv->regs,
-	      uc_priv->bank_name);
+
+	i = 0;
+	ret = dev_read_phandle_with_args(dev, "gpio-ranges",
+					 NULL, 3, i, &args);
+
+	while (ret != -ENOENT) {
+		priv->gpio_range |= GENMASK(args.args[2] + args.args[0] - 1,
+				    args.args[0]);
+
+		uc_priv->gpio_count += args.args[2];
+
+		ret = dev_read_phandle_with_args(dev, "gpio-ranges", NULL, 3,
+						 ++i, &args);
+	}
+
+	dev_dbg(dev, "addr = 0x%p bank_name = %s gpio_count = %d gpio_range = 0x%x\n",
+		(u32 *)priv->regs, uc_priv->bank_name, uc_priv->gpio_count,
+		priv->gpio_range);
 
 #ifdef CONFIG_CLK
 	struct clk clk;
-	int ret;
 	ret = clk_get_by_index(dev, 0, &clk);
 	if (ret < 0)
 		return ret;