[PATCH V1] pinctrl: qcom: spmi-gpio: Add support for qcom,gpios-disallowed property

[fenglinw]

From: Fenglin Wu <fenglinw@xxxxxxxxxxxxxx>

Add support for qcom,gpios-disallowed property which is used to exclude
PMIC GPIOs not owned by the APSS processor from the pinctrl device.

Signed-off-by: Fenglin Wu <fenglinw@xxxxxxxxxxxxxx>
---
 .../devicetree/bindings/pinctrl/qcom,pmic-gpio.txt |  12 ++
 drivers/pinctrl/qcom/pinctrl-spmi-gpio.c           | 202 +++++++++++++++++----
 2 files changed, 176 insertions(+), 38 deletions(-)

diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.txt b/Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.txt
index 8d893a8..435efe8 100644
--- a/Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.txt
+++ b/Documentation/devicetree/bindings/pinctrl/qcom,pmic-gpio.txt
@@ -43,6 +43,17 @@ PMIC's from Qualcomm.
 		    the first cell will be used to define gpio number and the
 		    second denotes the flags for this gpio
 
+- qcom,gpios-disallowed:
+	Usage: optional
+	Value type: <prop-encoded-array>
+	Definition: Array of the GPIO hardware numbers corresponding to GPIOs
+		    which the APSS processor is not allowed to configure.
+		    The hardware numbers are indexed from 1.
+		    The interrupt resources for these GPIOs must not be defined
+		    in "interrupts" and "interrupt-names" properties.
+		    GPIOs defined in this array won't be registered as pins
+		    in the pinctrl device or gpios in the gpio chip.
+
 Please refer to ../gpio/gpio.txt and ../interrupt-controller/interrupts.txt for
 a general description of GPIO and interrupt bindings.
 
@@ -206,6 +217,7 @@ Example:
 
 		gpio-controller;
 		#gpio-cells = <2>;
+		qcom,gpios-disallowed = <1 20>;
 
 		pm8921_gpio_keys: gpio-keys {
 			volume-keys {
diff --git a/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c b/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
index 664b641..74821af 100644
--- a/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
+++ b/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
@@ -96,6 +96,7 @@
  * struct pmic_gpio_pad - keep current GPIO settings
  * @base: Address base in SPMI device.
  * @irq: IRQ number which this GPIO generate.
+ * @gpio_idx: The index in GPIO's hardware number space (1-based)
  * @is_enabled: Set to false when GPIO should be put in high Z state.
  * @out_value: Cached pin output value
  * @have_buffer: Set to true if GPIO output could be configured in push-pull,
@@ -112,6 +113,7 @@
 struct pmic_gpio_pad {
 	u16		base;
 	int		irq;
+	int		gpio_idx;
 	bool		is_enabled;
 	bool		out_value;
 	bool		have_buffer;
@@ -130,6 +132,7 @@ struct pmic_gpio_state {
 	struct regmap	*map;
 	struct pinctrl_dev *ctrl;
 	struct gpio_chip chip;
+	const char **gpio_groups;
 };
 
 static const struct pinconf_generic_params pmic_gpio_bindings[] = {
@@ -231,7 +234,9 @@ static int pmic_gpio_get_function_groups(struct pinctrl_dev *pctldev,
 					 const char *const **groups,
 					 unsigned *const num_qgroups)
 {
-	*groups = pmic_gpio_groups;
+	struct pmic_gpio_state *state = pinctrl_dev_get_drvdata(pctldev);
+
+	*groups = state->gpio_groups;
 	*num_qgroups = pctldev->desc->npins;
 	return 0;
 }
@@ -455,7 +460,7 @@ static void pmic_gpio_config_dbg_show(struct pinctrl_dev *pctldev,
 
 	pad = pctldev->desc->pins[pin].drv_data;
 
-	seq_printf(s, " gpio%-2d:", pin + PMIC_GPIO_PHYSICAL_OFFSET);
+	seq_printf(s, " gpio%-2d:", pad->gpio_idx);
 
 	val = pmic_gpio_read(state, pad, PMIC_GPIO_REG_EN_CTL);
 
@@ -546,13 +551,29 @@ static int pmic_gpio_of_xlate(struct gpio_chip *chip,
 			      const struct of_phandle_args *gpio_desc,
 			      u32 *flags)
 {
+	int i;
+	struct pmic_gpio_state *state = gpiochip_get_data(chip);
+	struct pinctrl_desc *desc = state->ctrl->desc;
+	struct pmic_gpio_pad *pad;
+
 	if (chip->of_gpio_n_cells < 2)
 		return -EINVAL;
 
 	if (flags)
 		*flags = gpio_desc->args[1];
 
-	return gpio_desc->args[0] - PMIC_GPIO_PHYSICAL_OFFSET;
+	for (i = 0; i < chip->ngpio; i++) {
+		pad = desc->pins[i].drv_data;
+		if (pad->gpio_idx == gpio_desc->args[0]) {
+			dev_dbg(state->dev, "gpio%-2d xlate to pin%-2d\n",
+						gpio_desc->args[0], i);
+			return i;
+		}
+	}
+
+	dev_err(state->dev, "Couldn't find pin for gpio %d\n",
+				gpio_desc->args[0]);
+	return -ENODEV;
 }
 
 static int pmic_gpio_to_irq(struct gpio_chip *chip, unsigned pin)
@@ -688,43 +709,124 @@ static int pmic_gpio_probe(struct platform_device *pdev)
 	struct pinctrl_desc *pctrldesc;
 	struct pmic_gpio_pad *pad, *pads;
 	struct pmic_gpio_state *state;
-	int ret, npins, i;
-	u32 reg;
+	int ret, npins, ngpios, i, j, pin_idx;
+	int disallowed_count = 0;
+	u32 reg[2], start, size;
+	u32 *disallowed = NULL;
 
-	ret = of_property_read_u32(dev->of_node, "reg", &reg);
+	ret = of_property_read_u32_array(dev->of_node, "reg", reg, 2);
 	if (ret < 0) {
-		dev_err(dev, "missing base address");
+		dev_err(dev, "reg property reading failed\n");
 		return ret;
 	}
+	start = reg[0];
+	size = reg[1];
+
+	ngpios = size / PMIC_GPIO_ADDRESS_RANGE;
+	if (ngpios == 0) {
+		dev_err(dev, "no gpios assigned\n");
+		return -ENODEV;
+	}
 
-	npins = platform_irq_count(pdev);
-	if (!npins)
+	if (ngpios > ARRAY_SIZE(pmic_gpio_groups)) {
+		dev_err(dev, "reg property defines %d gpios, but only %d are allowed\n",
+				ngpios, (int)ARRAY_SIZE(pmic_gpio_groups));
 		return -EINVAL;
-	if (npins < 0)
-		return npins;
+	}
+
+	if (of_find_property(dev->of_node, "qcom,gpios-disallowed",
+					&disallowed_count)) {
+		disallowed_count /= sizeof(u32);
+		if (disallowed_count == 0) {
+			dev_err(dev, "No data in gpios-disallowed\n");
+			return -EINVAL;
+		}
 
-	BUG_ON(npins > ARRAY_SIZE(pmic_gpio_groups));
+		disallowed = kcalloc(disallowed_count, sizeof(u32), GFP_KERNEL);
+		if (disallowed == NULL)
+			return -ENOMEM;
+
+		ret = of_property_read_u32_array(dev->of_node,
+				"qcom,gpios-disallowed",
+				disallowed, disallowed_count);
+		if (ret < 0) {
+			dev_err(dev, "qcom,gpios-disallowed property reading failed, ret=%d\n",
+								ret);
+			goto err_free;
+		}
+
+		for (i = 0; i < disallowed_count; i++) {
+			if (disallowed[i] >= ngpios + PMIC_GPIO_PHYSICAL_OFFSET
+				|| disallowed[i] < PMIC_GPIO_PHYSICAL_OFFSET) {
+				dev_err(dev, "invalid gpio = %d specified in qcom,gpios-disallowed, supported values: %d to %d\n",
+					disallowed[i],
+					PMIC_GPIO_PHYSICAL_OFFSET,
+					ngpios - 1 + PMIC_GPIO_PHYSICAL_OFFSET);
+				ret = -EINVAL;
+				goto err_free;
+			}
+			for (j = 0; j < i; j++) {
+				if (disallowed[i] == disallowed[j]) {
+					dev_err(dev, "duplicate gpio = %d listed in qcom,gpios-disallowed\n",
+							disallowed[i]);
+					ret = -EINVAL;
+					goto err_free;
+				}
+			}
+			dev_dbg(dev, "gpio %d NOT supported\n", disallowed[i]);
+		}
+	} else {
+		disallowed_count = 0;
+	}
+
+	npins = ngpios - disallowed_count;
+	if (npins <= 0) {
+		dev_err(dev, "No pins assigned\n");
+		ret = -ENODEV;
+		goto err_free;
+	}
+	if (platform_irq_count(pdev) != npins) {
+		dev_err(dev, "%d IRQs defined but %d expected\n",
+				platform_irq_count(pdev), npins);
+		ret = -EINVAL;
+		goto err_free;
+	}
 
 	state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
-	if (!state)
-		return -ENOMEM;
+	if (!state) {
+		ret = -ENOMEM;
+		goto err_free;
+	}
 
 	platform_set_drvdata(pdev, state);
 
 	state->dev = &pdev->dev;
 	state->map = dev_get_regmap(dev->parent, NULL);
 
+	state->gpio_groups = devm_kcalloc(dev, sizeof(*state->gpio_groups),
+						npins, GFP_KERNEL);
+	if (!state->gpio_groups) {
+		ret = -ENOMEM;
+		goto err_free;
+	}
+
 	pindesc = devm_kcalloc(dev, npins, sizeof(*pindesc), GFP_KERNEL);
-	if (!pindesc)
-		return -ENOMEM;
+	if (!pindesc) {
+		ret = -ENOMEM;
+		goto err_free;
+	}
 
 	pads = devm_kcalloc(dev, npins, sizeof(*pads), GFP_KERNEL);
-	if (!pads)
-		return -ENOMEM;
+	if (!pads) {
+		ret = -ENOMEM;
+		goto err_free;
+	}
 
 	pctrldesc = devm_kzalloc(dev, sizeof(*pctrldesc), GFP_KERNEL);
-	if (!pctrldesc)
-		return -ENOMEM;
+	if (!pctrldesc) {
+		ret = -ENOMEM;
+		goto err_free;
+	}
 
 	pctrldesc->pctlops = &pmic_gpio_pinctrl_ops;
 	pctrldesc->pmxops = &pmic_gpio_pinmux_ops;
@@ -738,22 +840,42 @@ static int pmic_gpio_probe(struct platform_device *pdev)
 #ifdef CONFIG_DEBUG_FS
 	pctrldesc->custom_conf_items = pmic_conf_items;
 #endif
+	for (pin_idx = 0, i = 0; i < ngpios; i++) {
+		for (j = 0; j < disallowed_count; j++) {
+			if (i + PMIC_GPIO_PHYSICAL_OFFSET == disallowed[j])
+				break;
+		}
+		if (j != disallowed_count)
+			continue;
 
-	for (i = 0; i < npins; i++, pindesc++) {
-		pad = &pads[i];
+		pad = &pads[pin_idx];
 		pindesc->drv_data = pad;
-		pindesc->number = i;
+		pindesc->number = pin_idx;
 		pindesc->name = pmic_gpio_groups[i];
 
-		pad->irq = platform_get_irq(pdev, i);
-		if (pad->irq < 0)
-			return pad->irq;
+		pad->gpio_idx = i + PMIC_GPIO_PHYSICAL_OFFSET;
+		pad->irq = platform_get_irq(pdev, pin_idx);
+		if (pad->irq < 0) {
+			dev_err(state->dev,
+				"failed to get irq for gpio %d (pin %d), ret=%d\n",
+					pad->gpio_idx, pin_idx, pad->irq);
+			ret = pad->irq;
+			goto err_free;
+		}
+		/* Every pin is a group */
+		state->gpio_groups[pin_idx] = pmic_gpio_groups[i];
 
-		pad->base = reg + i * PMIC_GPIO_ADDRESS_RANGE;
+		pad->base = start + i * PMIC_GPIO_ADDRESS_RANGE;
 
 		ret = pmic_gpio_populate(state, pad);
-		if (ret < 0)
-			return ret;
+		if (ret < 0) {
+			dev_err(state->dev,
+				"failed to populate gpio %d, ret=%d\n",
+							i, ret);
+			goto err_free;
+		}
+		pindesc++;
+		pin_idx++;
 	}
 
 	state->chip = pmic_gpio_gpio_template;
@@ -765,25 +887,29 @@ static int pmic_gpio_probe(struct platform_device *pdev)
 	state->chip.can_sleep = false;
 
 	state->ctrl = devm_pinctrl_register(dev, pctrldesc, state);
-	if (IS_ERR(state->ctrl))
-		return PTR_ERR(state->ctrl);
+	if (IS_ERR(state->ctrl)) {
+		ret = PTR_ERR(state->ctrl);
+		dev_err(state->dev, "failed to register pinctrl device, ret=%d\n",
+							ret);
+		goto err_free;
+	}
 
 	ret = gpiochip_add_data(&state->chip, state);
 	if (ret) {
-		dev_err(state->dev, "can't add gpio chip\n");
-		return ret;
+		dev_err(state->dev, "can't add gpio chip, ret=%d\n", ret);
+		goto err_free;
 	}
 
 	ret = gpiochip_add_pin_range(&state->chip, dev_name(dev), 0, 0, npins);
 	if (ret) {
-		dev_err(dev, "failed to add pin range\n");
-		goto err_range;
+		dev_err(dev, "failed to add pin range\n, ret=%d\n", ret);
+		gpiochip_remove(&state->chip);
+		goto err_free;
 	}
 
-	return 0;
+err_free:
+	kfree(disallowed);
 
-err_range:
-	gpiochip_remove(&state->chip);
 	return ret;
 }
 
-- 
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