1 files changed, 344 insertions, 48 deletions

diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
index af9d8b3a711d..37600faf4a4b 100644
--- a/drivers/gpio/gpio-aggregator.c
+++ b/drivers/gpio/gpio-aggregator.c
@@ -12,6 +12,7 @@
 #include <linux/configfs.h>
 #include <linux/ctype.h>
 #include <linux/delay.h>
+#include <linux/export.h>
 #include <linux/idr.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -28,6 +29,7 @@
 
 #include <linux/gpio/consumer.h>
 #include <linux/gpio/driver.h>
+#include <linux/gpio/forwarder.h>
 #include <linux/gpio/machine.h>
 
 #include "dev-sync-probe.h"
@@ -244,18 +246,34 @@ struct gpiochip_fwd {
 		spinlock_t slock;	/* protects tmp[] if !can_sleep */
 	};
 	struct gpiochip_fwd_timing *delay_timings;
+	void *data;
+	unsigned long *valid_mask;
 	unsigned long tmp[];		/* values and descs for multiple ops */
 };
 
-#define fwd_tmp_values(fwd)	&(fwd)->tmp[0]
-#define fwd_tmp_descs(fwd)	(void *)&(fwd)->tmp[BITS_TO_LONGS((fwd)->chip.ngpio)]
+#define fwd_tmp_values(fwd)	(&(fwd)->tmp[0])
+#define fwd_tmp_descs(fwd)	((void *)&(fwd)->tmp[BITS_TO_LONGS((fwd)->chip.ngpio)])
 
 #define fwd_tmp_size(ngpios)	(BITS_TO_LONGS((ngpios)) + (ngpios))
 
+static int gpio_fwd_request(struct gpio_chip *chip, unsigned int offset)
+{
+	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+	return test_bit(offset, fwd->valid_mask) ? 0 : -ENODEV;
+}
+
 static int gpio_fwd_get_direction(struct gpio_chip *chip, unsigned int offset)
 {
 	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
 
+	/*
+	 * get_direction() is called during gpiochip registration, return
+	 * -ENODEV if there is no GPIO desc for the line.
+	 */
+	if (!test_bit(offset, fwd->valid_mask))
+		return -ENODEV;
+
 	return gpiod_get_direction(fwd->descs[offset]);
 }
 
@@ -453,10 +471,11 @@ static int gpiochip_fwd_delay_of_xlate(struct gpio_chip *chip,
 	return line;
 }
 
-static int gpiochip_fwd_setup_delay_line(struct device *dev, struct gpio_chip *chip,
-					 struct gpiochip_fwd *fwd)
+static int gpiochip_fwd_setup_delay_line(struct gpiochip_fwd *fwd)
 {
-	fwd->delay_timings = devm_kcalloc(dev, chip->ngpio,
+	struct gpio_chip *chip = &fwd->chip;
+
+	fwd->delay_timings = devm_kcalloc(chip->parent, chip->ngpio,
 					  sizeof(*fwd->delay_timings),
 					  GFP_KERNEL);
 	if (!fwd->delay_timings)
@@ -468,67 +487,235 @@ static int gpiochip_fwd_setup_delay_line(struct device *dev, struct gpio_chip *c
 	return 0;
 }
 #else
-static int gpiochip_fwd_setup_delay_line(struct device *dev, struct gpio_chip *chip,
-					 struct gpiochip_fwd *fwd)
+static int gpiochip_fwd_setup_delay_line(struct gpiochip_fwd *fwd)
 {
 	return 0;
 }
 #endif	/* !CONFIG_OF_GPIO */
 
 /**
- * gpiochip_fwd_create() - Create a new GPIO forwarder
- * @dev: Parent device pointer
- * @ngpios: Number of GPIOs in the forwarder.
- * @descs: Array containing the GPIO descriptors to forward to.
- *         This array must contain @ngpios entries, and must not be deallocated
- *         before the forwarder has been destroyed again.
- * @features: Bitwise ORed features as defined with FWD_FEATURE_*.
+ * gpiochip_fwd_get_gpiochip - Get the GPIO chip for the GPIO forwarder
+ * @fwd: GPIO forwarder
  *
- * This function creates a new gpiochip, which forwards all GPIO operations to
- * the passed GPIO descriptors.
+ * Returns: The GPIO chip for the GPIO forwarder
+ */
+struct gpio_chip *gpiochip_fwd_get_gpiochip(struct gpiochip_fwd *fwd)
+{
+	return &fwd->chip;
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_get_gpiochip, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_get_data - Get driver-private data for the GPIO forwarder
+ * @fwd: GPIO forwarder
  *
- * Return: An opaque object pointer, or an ERR_PTR()-encoded negative error
- *         code on failure.
+ * Returns: The driver-private data for the GPIO forwarder
  */
-static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
-						unsigned int ngpios,
-						struct gpio_desc *descs[],
-						unsigned long features)
+void *gpiochip_fwd_get_data(struct gpiochip_fwd *fwd)
+{
+	return fwd->data;
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_get_data, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_request - Request a line of the GPIO forwarder
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line to request
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_request(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_request(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_request, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_get_direction - Return the current direction of a GPIO forwarder line
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ *
+ * Returns: 0 for output, 1 for input, or an error code in case of error.
+ */
+int gpiochip_fwd_gpio_get_direction(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_get_direction(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_get_direction, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_direction_output - Set a GPIO forwarder line direction to
+ * output
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ * @value: value to set
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_direction_output(struct gpiochip_fwd *fwd, unsigned int offset,
+				       int value)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_direction_output(gc, offset, value);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_direction_output, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_direction_input - Set a GPIO forwarder line direction to input
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_direction_input(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_direction_input(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_direction_input, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_get - Return a GPIO forwarder line's value
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ *
+ * Returns: The GPIO's logical value, i.e. taking the ACTIVE_LOW status into
+ * account, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_get(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_get(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_get, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_get_multiple - Get values for multiple GPIO forwarder lines
+ * @fwd: GPIO forwarder
+ * @mask: bit mask array; one bit per line; BITS_PER_LONG bits per word defines
+ *        which lines are to be read
+ * @bits: bit value array; one bit per line; BITS_PER_LONG bits per word will
+ *        contains the read values for the lines specified by mask
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_get_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
+				   unsigned long *bits)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_get_multiple_locked(gc, mask, bits);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_get_multiple, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_set - Assign value to a GPIO forwarder line.
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ * @value: value to set
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_set(struct gpiochip_fwd *fwd, unsigned int offset, int value)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_set(gc, offset, value);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_set, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_set_multiple - Assign values to multiple GPIO forwarder lines
+ * @fwd: GPIO forwarder
+ * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
+ *        defines which outputs are to be changed
+ * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
+ *        defines the values the outputs specified by mask are to be set to
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_set_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
+				   unsigned long *bits)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_set_multiple_locked(gc, mask, bits);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_set_multiple, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_set_config - Set @config for a GPIO forwarder line
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ * @config: Same packed config format as generic pinconf
+ *
+ * Returns: 0 on success, %-ENOTSUPP if the controller doesn't support setting
+ * the configuration.
+ */
+int gpiochip_fwd_gpio_set_config(struct gpiochip_fwd *fwd, unsigned int offset,
+				 unsigned long config)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_set_config(gc, offset, config);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_set_config, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_to_irq - Return the IRQ corresponding to a GPIO forwarder line
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ *
+ * Returns: The Linux IRQ corresponding to the passed line, or an error code in
+ * case of error.
+ */
+int gpiochip_fwd_gpio_to_irq(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_to_irq(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_to_irq, "GPIO_FORWARDER");
+
+/**
+ * devm_gpiochip_fwd_alloc - Allocate and initialize a new GPIO forwarder
+ * @dev: Parent device pointer
+ * @ngpios: Number of GPIOs in the forwarder
+ *
+ * Returns: An opaque object pointer, or an ERR_PTR()-encoded negative error
+ * code on failure.
+ */
+struct gpiochip_fwd *devm_gpiochip_fwd_alloc(struct device *dev,
+					     unsigned int ngpios)
 {
-	const char *label = dev_name(dev);
 	struct gpiochip_fwd *fwd;
 	struct gpio_chip *chip;
-	unsigned int i;
-	int error;
 
-	fwd = devm_kzalloc(dev, struct_size(fwd, tmp, fwd_tmp_size(ngpios)),
-			   GFP_KERNEL);
+	fwd = devm_kzalloc(dev, struct_size(fwd, tmp, fwd_tmp_size(ngpios)), GFP_KERNEL);
 	if (!fwd)
 		return ERR_PTR(-ENOMEM);
 
-	chip = &fwd->chip;
-
-	/*
-	 * If any of the GPIO lines are sleeping, then the entire forwarder
-	 * will be sleeping.
-	 * If any of the chips support .set_config(), then the forwarder will
-	 * support setting configs.
-	 */
-	for (i = 0; i < ngpios; i++) {
-		struct gpio_chip *parent = gpiod_to_chip(descs[i]);
+	fwd->descs = devm_kcalloc(dev, ngpios, sizeof(*fwd->descs), GFP_KERNEL);
+	if (!fwd->descs)
+		return ERR_PTR(-ENOMEM);
 
-		dev_dbg(dev, "%u => gpio %d irq %d\n", i,
-			desc_to_gpio(descs[i]), gpiod_to_irq(descs[i]));
+	fwd->valid_mask = devm_bitmap_zalloc(dev, ngpios, GFP_KERNEL);
+	if (!fwd->valid_mask)
+		return ERR_PTR(-ENOMEM);
 
-		if (gpiod_cansleep(descs[i]))
-			chip->can_sleep = true;
-		if (parent && parent->set_config)
-			chip->set_config = gpio_fwd_set_config;
-	}
+	chip = &fwd->chip;
 
-	chip->label = label;
+	chip->label = dev_name(dev);
 	chip->parent = dev;
 	chip->owner = THIS_MODULE;
+	chip->request = gpio_fwd_request;
 	chip->get_direction = gpio_fwd_get_direction;
 	chip->direction_input = gpio_fwd_direction_input;
 	chip->direction_output = gpio_fwd_direction_output;
@@ -539,20 +726,128 @@ static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
 	chip->to_irq = gpio_fwd_to_irq;
 	chip->base = -1;
 	chip->ngpio = ngpios;
-	fwd->descs = descs;
+
+	return fwd;
+}
+EXPORT_SYMBOL_NS_GPL(devm_gpiochip_fwd_alloc, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_desc_add - Add a GPIO desc in the forwarder
+ * @fwd: GPIO forwarder
+ * @desc: GPIO descriptor to register
+ * @offset: offset for the GPIO in the forwarder
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_desc_add(struct gpiochip_fwd *fwd, struct gpio_desc *desc,
+			  unsigned int offset)
+{
+	struct gpio_chip *chip = &fwd->chip;
+
+	if (offset >= chip->ngpio)
+		return -EINVAL;
+
+	if (test_and_set_bit(offset, fwd->valid_mask))
+		return -EEXIST;
+
+	/*
+	 * If any of the GPIO lines are sleeping, then the entire forwarder
+	 * will be sleeping.
+	 */
+	if (gpiod_cansleep(desc))
+		chip->can_sleep = true;
+
+	fwd->descs[offset] = desc;
+
+	dev_dbg(chip->parent, "%u => gpio %d irq %d\n", offset,
+		desc_to_gpio(desc), gpiod_to_irq(desc));
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_desc_add, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_desc_free - Remove a GPIO desc from the forwarder
+ * @fwd: GPIO forwarder
+ * @offset: offset of GPIO desc to remove
+ */
+void gpiochip_fwd_desc_free(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	if (test_and_clear_bit(offset, fwd->valid_mask))
+		gpiod_put(fwd->descs[offset]);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_desc_free, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_register - Register a GPIO forwarder
+ * @fwd: GPIO forwarder
+ * @data: driver-private data associated with this forwarder
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_register(struct gpiochip_fwd *fwd, void *data)
+{
+	struct gpio_chip *chip = &fwd->chip;
+
+	/*
+	 * Some gpio_desc were not registered. They will be registered at runtime
+	 * but we have to suppose they can sleep.
+	 */
+	if (!bitmap_full(fwd->valid_mask, chip->ngpio))
+		chip->can_sleep = true;
 
 	if (chip->can_sleep)
 		mutex_init(&fwd->mlock);
 	else
 		spin_lock_init(&fwd->slock);
 
+	fwd->data = data;
+
+	return devm_gpiochip_add_data(chip->parent, chip, fwd);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_register, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_create() - Create a new GPIO forwarder
+ * @dev: Parent device pointer
+ * @ngpios: Number of GPIOs in the forwarder.
+ * @descs: Array containing the GPIO descriptors to forward to.
+ *         This array must contain @ngpios entries, and can be deallocated
+ *         as the forwarder has its own array.
+ * @features: Bitwise ORed features as defined with FWD_FEATURE_*.
+ *
+ * This function creates a new gpiochip, which forwards all GPIO operations to
+ * the passed GPIO descriptors.
+ *
+ * Return: An opaque object pointer, or an ERR_PTR()-encoded negative error
+ *         code on failure.
+ */
+static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
+						unsigned int ngpios,
+						struct gpio_desc *descs[],
+						unsigned long features)
+{
+	struct gpiochip_fwd *fwd;
+	unsigned int i;
+	int error;
+
+	fwd = devm_gpiochip_fwd_alloc(dev, ngpios);
+	if (IS_ERR(fwd))
+		return fwd;
+
+	for (i = 0; i < ngpios; i++) {
+		error = gpiochip_fwd_desc_add(fwd, descs[i], i);
+		if (error)
+			return ERR_PTR(error);
+	}
+
 	if (features & FWD_FEATURE_DELAY) {
-		error = gpiochip_fwd_setup_delay_line(dev, chip, fwd);
+		error = gpiochip_fwd_setup_delay_line(fwd);
 		if (error)
 			return ERR_PTR(error);
 	}
 
-	error = devm_gpiochip_add_data(dev, chip, fwd);
+	error = gpiochip_fwd_register(fwd, NULL);
 	if (error)
 		return ERR_PTR(error);
 
@@ -1334,6 +1629,7 @@ static int gpio_aggregator_probe(struct platform_device *pdev)
 		return PTR_ERR(fwd);
 
 	platform_set_drvdata(pdev, fwd);
+	devm_kfree(dev, descs);
 	return 0;
 }