pinctrl: single: create new gpio function range

Since gpio driver could create gpio range in DTS, it could invoke
pinctrl_request_gpio(). In the pinctrl-single driver, it needs to
configure pins with gpio function mode.

A new gpio function range should be created in DTS file in below.

pinctrl-single,gpio-range = <phandle pin_offset nr_pins gpio_func>;

range: gpio-range {
	#pinctrl-single,gpio-range-cells = <3>;
};

The gpio-ranges property is used in gpio driver and the
pinctrl-single,gpio-range property is used in pinctrl-single driver.

1. gpio-ranges is used for gpio driver in below.
   gpio-ranges = <phandle gpio_offset_in_chip pin_offset nr_pins>
	gpio-ranges = < &pmx0 0 89 1 &pmx0 1 89 1 &pmx0 2 90 1
			&pmx0 3 90 1 &pmx0 4 91 1 &pmx0 5 92 1>;

2. gpio driver could get pin offset from gpio-ranges property.
   pinctrl-single driver could get gpio function mode from gpio_func
   that is stored in @gpiofuncs list in struct pcs_device.
   This new pinctrl-single,gpio-range is used as complement for
   gpio-ranges property in gpio driver.

Signed-off-by: Haojian Zhuang <haojian.zhuang@linaro.org>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 71 insertions, 2 deletions

diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index 0c0e2da9d880..f4bc602cdb08 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -77,6 +77,20 @@ struct pcs_function {
 };
 
 /**
+ * struct pcs_gpiofunc_range - pin ranges with same mux value of gpio function
+ * @offset:     offset base of pins
+ * @npins:      number pins with the same mux value of gpio function
+ * @gpiofunc:   mux value of gpio function
+ * @node:       list node
+ */
+struct pcs_gpiofunc_range {
+        unsigned offset;
+        unsigned npins;
+        unsigned gpiofunc;
+        struct list_head node;
+};
+
+/**
  * struct pcs_data - wrapper for data needed by pinctrl framework
  * @pa:         pindesc array
  * @cur:        index to current element
@@ -123,6 +137,7 @@ struct pcs_name {
  * @ftree:      function index radix tree
  * @pingroups:  list of pingroups
  * @functions:  list of functions
+ * @gpiofuncs:  list of gpio functions
  * @ngroups:    number of pingroups
  * @nfuncs:     number of functions
  * @desc:       pin controller descriptor
@@ -148,6 +163,7 @@ struct pcs_device {
         struct radix_tree_root ftree;
         struct list_head pingroups;
         struct list_head functions;
+        struct list_head gpiofuncs;
         unsigned ngroups;
         unsigned nfuncs;
         struct pinctrl_desc desc;
@@ -403,9 +419,26 @@ static void pcs_disable(struct pinctrl_dev *pctldev, unsigned fselector,
 }
 
 static int pcs_request_gpio(struct pinctrl_dev *pctldev,
-                        struct pinctrl_gpio_range *range, unsigned offset)
+                            struct pinctrl_gpio_range *range, unsigned pin)
 {
-        return -ENOTSUPP;
+        struct pcs_device *pcs = pinctrl_dev_get_drvdata(pctldev);
+        struct pcs_gpiofunc_range *frange = NULL;
+        struct list_head *pos, *tmp;
+        int mux_bytes = 0;
+        unsigned data;
+
+        list_for_each_safe(pos, tmp, &pcs->gpiofuncs) {
+                frange = list_entry(pos, struct pcs_gpiofunc_range, node);
+                if (pin >= frange->offset + frange->npins
+                        || pin < frange->offset)
+                        continue;
+                mux_bytes = pcs->width / BITS_PER_BYTE;
+                data = pcs->read(pcs->base + pin * mux_bytes) & ~pcs->fmask;
+                data |= frange->gpiofunc;
+                pcs->write(data, pcs->base + pin * mux_bytes);
+                break;
+        }
+        return 0;
 }
 
 static const struct pinmux_ops pcs_pinmux_ops = {
@@ -879,6 +912,37 @@ static void pcs_free_resources(struct pcs_device *pcs)
 
 static struct of_device_id pcs_of_match[];
 
+static int pcs_add_gpio_func(struct device_node *node, struct pcs_device *pcs)
+{
+        const char *propname = "pinctrl-single,gpio-range";
+        const char *cellname = "#pinctrl-single,gpio-range-cells";
+        struct of_phandle_args gpiospec;
+        struct pcs_gpiofunc_range *range;
+        int ret, i;
+
+        for (i = 0; ; i++) {
+                ret = of_parse_phandle_with_args(node, propname, cellname,
+                                                 i, &gpiospec);
+                /* Do not treat it as error. Only treat it as end condition. */
+                if (ret) {
+                        ret = 0;
+                        break;
+                }
+                range = devm_kzalloc(pcs->dev, sizeof(*range), GFP_KERNEL);
+                if (!range) {
+                        ret = -ENOMEM;
+                        break;
+                }
+                range->offset = gpiospec.args[0];
+                range->npins = gpiospec.args[1];
+                range->gpiofunc = gpiospec.args[2];
+                mutex_lock(&pcs->mutex);
+                list_add_tail(&range->node, &pcs->gpiofuncs);
+                mutex_unlock(&pcs->mutex);
+        }
+        return ret;
+}
+
 static int pcs_probe(struct platform_device *pdev)
 {
         struct device_node *np = pdev->dev.of_node;
@@ -900,6 +964,7 @@ static int pcs_probe(struct platform_device *pdev)
         mutex_init(&pcs->mutex);
         INIT_LIST_HEAD(&pcs->pingroups);
         INIT_LIST_HEAD(&pcs->functions);
+        INIT_LIST_HEAD(&pcs->gpiofuncs);
 
         PCS_GET_PROP_U32("pinctrl-single,register-width", &pcs->width,
                          "register width not specified\n");
@@ -975,6 +1040,10 @@ static int pcs_probe(struct platform_device *pdev)
                 goto free;
         }
 
+        ret = pcs_add_gpio_func(np, pcs);
+        if (ret < 0)
+                goto free;
+
         dev_info(pcs->dev, "%i pins at pa %p size %u\n",
                  pcs->desc.npins, pcs->base, pcs->size);