diff mbox series

[RFC,6/7] pinctrl-scmi: Add GPIO support

Message ID 901a636b06f5ef25f8c0021c514bfcc01344c5df.1746443762.git.dan.carpenter@linaro.org
State New
Headers show
Series pinctrl-scmi: Add GPIO support | expand

Commit Message

Dan Carpenter May 5, 2025, 11:39 a.m. UTC
This adds GPIO support to the SCMI pin controller driver.  It's an RFC
patch because I'm not really sure how these are used and so I don't
know how they should be configured via devicetree.  I've labeled the
places where I think devicetree configuration would go with a FIXME.

This driver was based on work from Takahiro AKASHI.

Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
---
 drivers/pinctrl/pinctrl-scmi.c | 206 ++++++++++++++++++++++++++++++++-
 1 file changed, 205 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/pinctrl/pinctrl-scmi.c b/drivers/pinctrl/pinctrl-scmi.c
index f369f0354e43..40b432aa4756 100644
--- a/drivers/pinctrl/pinctrl-scmi.c
+++ b/drivers/pinctrl/pinctrl-scmi.c
@@ -6,6 +6,7 @@ 
  * Copyright 2024 NXP
  */
 
+#include <linux/bitmap.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/errno.h>
@@ -16,6 +17,9 @@ 
 #include <linux/slab.h>
 #include <linux/types.h>
 
+#include <linux/gpio/driver.h>
+
+#include <linux/pinctrl/consumer.h>
 #include <linux/pinctrl/machine.h>
 #include <linux/pinctrl/pinconf.h>
 #include <linux/pinctrl/pinconf-generic.h>
@@ -42,6 +46,7 @@  struct scmi_pinctrl {
 	unsigned int nr_functions;
 	struct pinctrl_pin_desc *pins;
 	unsigned int nr_pins;
+	struct gpio_chip *gc;
 };
 
 static int pinctrl_scmi_get_groups_count(struct pinctrl_dev *pctldev)
@@ -505,6 +510,197 @@  static int pinctrl_scmi_get_pins(struct scmi_pinctrl *pmx,
 	return 0;
 }
 
+static int pinctrl_gpio_init_valid_mask(struct gpio_chip *gc,
+				    unsigned long *valid_mask,
+				    unsigned int ngpios)
+{
+	bitmap_fill(valid_mask, ngpios);
+	return 0;
+}
+
+static int pinctrl_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+	unsigned long config;
+	bool in, out;
+	int ret;
+
+	config = PIN_CONFIG_INPUT_ENABLE;
+	ret = pinctrl_gpio_get_config(gc, offset, &config);
+	if (ret)
+		return ret;
+	in = config;
+
+	config = PIN_CONFIG_OUTPUT_ENABLE;
+	ret = pinctrl_gpio_get_config(gc, offset, &config);
+	if (ret)
+		return ret;
+	out = config;
+
+	/* Consistency check - in theory both can be enabled! */
+	if (in && !out)
+		return GPIO_LINE_DIRECTION_IN;
+	if (!in && out)
+		return GPIO_LINE_DIRECTION_OUT;
+
+	return -EINVAL;
+}
+
+static int pinctrl_gpio_direction_output_wrapper(struct gpio_chip *gc,
+						 unsigned int offset, int val)
+{
+	return pinctrl_gpio_direction_output(gc, offset);
+}
+
+static int pinctrl_gpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+	unsigned long config;
+	int ret;
+
+	config = PIN_CONFIG_INPUT_VALUE;
+	ret = pinctrl_gpio_get_config(gc, offset, &config);
+	if (ret)
+		return ret;
+
+	return config;
+}
+
+static void pinctrl_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
+{
+	unsigned long config;
+
+	config = PIN_CONF_PACKED(PIN_CONFIG_OUTPUT, val);
+	pinctrl_gpio_set_config(gc, offset, config);
+}
+
+static int pinctrl_gc_to_func(struct gpio_chip *gc)
+{
+	struct scmi_pinctrl *pmx = gpiochip_get_data(gc);
+
+	return (gc - pmx->gc);
+}
+
+static int gpio_add_pin_ranges(struct gpio_chip *gc)
+{
+	struct scmi_pinctrl *pmx = gpiochip_get_data(gc);
+	const char * const *p_groups;
+	unsigned int n_groups;
+	int func = pinctrl_gc_to_func(gc);
+	int group;
+	int ret;
+
+	ret = pmx->pctl_desc.pmxops->get_function_groups(pmx->pctldev, func, &p_groups, &n_groups);
+	if (ret)
+		return ret;
+
+	// FIXME: fix the correct group from the device tree
+	for (group = 0; group < n_groups; group++) {
+		ret = gpiochip_add_pingroup_range(gc, pmx->pctldev, 0, p_groups[group]);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int get_nr_pins_in_function(struct scmi_pinctrl *pmx, int func)
+{
+	const char * const *pin_groups;
+	unsigned int n_groups;
+	const unsigned int *pins;
+	unsigned int n_pins;
+	int total = 0;
+	int i, ret;
+
+	// FIXME: get the correct number of gc.ngpio
+	// Find the right group from the device tree
+	ret = pmx->pctl_desc.pmxops->get_function_groups(pmx->pctldev, func, &pin_groups, &n_groups);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < n_groups; i++) {
+		ret = pinctrl_get_group_pins(pmx->pctldev, pin_groups[i], &pins, &n_pins);
+		if (ret)
+			return ret;
+		total += n_pins;
+	}
+
+	return total;
+}
+
+static int register_scmi_pinctrl_gpio_handler(struct device *dev, struct scmi_pinctrl *pmx)
+{
+	struct fwnode_handle *gpio = NULL;
+	int ret, i;
+
+	gpio = fwnode_get_named_child_node(dev->fwnode, "gpio");
+	if (!gpio)
+		return 0;
+
+	pmx->gc = devm_kcalloc(dev, pmx->nr_functions, sizeof(*pmx->gc), GFP_KERNEL);
+	if (!pmx->gc)
+		return -ENOMEM;
+
+	for (i = 0; i < pmx->nr_functions; i++) {
+		const char *fn_name;
+
+		ret = pinctrl_ops->is_gpio(pmx->ph, i, FUNCTION_TYPE);
+		if (ret < 0)
+			return ret;
+		if (ret == false)
+			continue;
+
+		ret = pinctrl_ops->name_get(pmx->ph, i, FUNCTION_TYPE, &fn_name);
+		if (ret)
+			return ret;
+
+		pmx->gc[i].label = devm_kasprintf(dev, GFP_KERNEL, "%s", fn_name);
+		if (!pmx->gc[i].label)
+			return -ENOMEM;
+
+		pmx->gc[i].owner = THIS_MODULE;
+		pmx->gc[i].get = pinctrl_gpio_get;
+		pmx->gc[i].set = pinctrl_gpio_set;
+		pmx->gc[i].get_direction = pinctrl_gpio_get_direction;
+		pmx->gc[i].direction_input = pinctrl_gpio_direction_input;
+		pmx->gc[i].direction_output = pinctrl_gpio_direction_output_wrapper;
+		pmx->gc[i].add_pin_ranges = gpio_add_pin_ranges;
+
+		// FIXME: verify that this is correct
+		pmx->gc[i].can_sleep = true;
+
+		ret = get_nr_pins_in_function(pmx, i);
+		if (ret < 0)
+			return ret;
+		pmx->gc[i].ngpio = ret;
+
+		pmx->gc[i].init_valid_mask = pinctrl_gpio_init_valid_mask;
+		pmx->gc[i].parent = dev;
+		pmx->gc[i].base = -1;
+	}
+
+	return 0;
+}
+
+static int scmi_gpiochip_add_data(struct device *dev, struct scmi_pinctrl *pmx)
+{
+	int ret;
+	int i;
+
+	for (i = 0; i < pmx->nr_functions; i++) {
+		ret = pinctrl_ops->is_gpio(pmx->ph, i, FUNCTION_TYPE);
+		if (ret < 0)
+			return ret;
+		if (ret == false)
+			continue;
+
+		ret = devm_gpiochip_add_data(dev, &pmx->gc[i], pmx);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 static const char * const scmi_pinctrl_blocklist[] = {
 	"fsl,imx95",
 	NULL
@@ -558,7 +754,15 @@  static int scmi_pinctrl_probe(struct scmi_device *sdev)
 	if (!pmx->functions)
 		return -ENOMEM;
 
-	return pinctrl_enable(pmx->pctldev);
+	ret = register_scmi_pinctrl_gpio_handler(dev, pmx);
+	if (ret)
+		return ret;
+
+	ret = pinctrl_enable(pmx->pctldev);
+	if (ret)
+		return ret;
+
+	return scmi_gpiochip_add_data(dev, pmx);
 }
 
 static const struct scmi_device_id scmi_id_table[] = {