pinctrl: add driver for meson-gxbb pin controller
Add a pin controller driver for Meson GXBB adapted from Linux kernel.
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/pinctrl/meson/pinctrl-meson.c b/drivers/pinctrl/meson/pinctrl-meson.c
new file mode 100644
index 0000000..d21a3dd
--- /dev/null
+++ b/drivers/pinctrl/meson/pinctrl-meson.c
@@ -0,0 +1,179 @@
+/*
+ * (C) Copyright 2016 - Beniamino Galvani <b.galvani@gmail.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm/device.h>
+#include <dm/pinctrl.h>
+#include <fdt_support.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/sizes.h>
+
+#include "pinctrl-meson.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const char *meson_pinctrl_dummy_name = "_dummy";
+
+static int meson_pinctrl_get_groups_count(struct udevice *dev)
+{
+ struct meson_pinctrl *priv = dev_get_priv(dev);
+
+ return priv->data->num_groups;
+}
+
+static const char *meson_pinctrl_get_group_name(struct udevice *dev,
+ unsigned selector)
+{
+ struct meson_pinctrl *priv = dev_get_priv(dev);
+
+ if (!priv->data->groups[selector].name)
+ return meson_pinctrl_dummy_name;
+
+ return priv->data->groups[selector].name;
+}
+
+static int meson_pinmux_get_functions_count(struct udevice *dev)
+{
+ struct meson_pinctrl *priv = dev_get_priv(dev);
+
+ return priv->data->num_funcs;
+}
+
+static const char *meson_pinmux_get_function_name(struct udevice *dev,
+ unsigned selector)
+{
+ struct meson_pinctrl *priv = dev_get_priv(dev);
+
+ return priv->data->funcs[selector].name;
+}
+
+static void meson_pinmux_disable_other_groups(struct meson_pinctrl *priv,
+ unsigned int pin, int sel_group)
+{
+ struct meson_pmx_group *group;
+ void __iomem *addr;
+ int i, j;
+
+ for (i = 0; i < priv->data->num_groups; i++) {
+ group = &priv->data->groups[i];
+ if (group->is_gpio || i == sel_group)
+ continue;
+
+ for (j = 0; j < group->num_pins; j++) {
+ if (group->pins[j] == pin) {
+ /* We have found a group using the pin */
+ debug("pinmux: disabling %s\n", group->name);
+ addr = priv->reg_mux + group->reg * 4;
+ writel(readl(addr) & ~BIT(group->bit), addr);
+ }
+ }
+ }
+}
+
+static int meson_pinmux_group_set(struct udevice *dev,
+ unsigned group_selector,
+ unsigned func_selector)
+{
+ struct meson_pinctrl *priv = dev_get_priv(dev);
+ const struct meson_pmx_group *group;
+ const struct meson_pmx_func *func;
+ void __iomem *addr;
+ int i;
+
+ group = &priv->data->groups[group_selector];
+ func = &priv->data->funcs[func_selector];
+
+ debug("pinmux: set group %s func %s\n", group->name, func->name);
+
+ /*
+ * Disable groups using the same pins.
+ * The selected group is not disabled to avoid glitches.
+ */
+ for (i = 0; i < group->num_pins; i++) {
+ meson_pinmux_disable_other_groups(priv,
+ group->pins[i],
+ group_selector);
+ }
+
+ /* Function 0 (GPIO) doesn't need any additional setting */
+ if (func_selector) {
+ addr = priv->reg_mux + group->reg * 4;
+ writel(readl(addr) | BIT(group->bit), addr);
+ }
+
+ return 0;
+}
+
+const struct pinctrl_ops meson_pinctrl_ops = {
+ .get_groups_count = meson_pinctrl_get_groups_count,
+ .get_group_name = meson_pinctrl_get_group_name,
+ .get_functions_count = meson_pinmux_get_functions_count,
+ .get_function_name = meson_pinmux_get_function_name,
+ .pinmux_group_set = meson_pinmux_group_set,
+ .set_state = pinctrl_generic_set_state,
+};
+
+static fdt_addr_t parse_address(int offset, const char *name, int na, int ns)
+{
+ int index, len = 0;
+ const fdt32_t *reg;
+
+ index = fdt_find_string(gd->fdt_blob, offset, "reg-names", name);
+ if (index < 0)
+ return FDT_ADDR_T_NONE;
+
+ reg = fdt_getprop(gd->fdt_blob, offset, "reg", &len);
+ if (!reg || (len <= (index * sizeof(fdt32_t) * (na + ns))))
+ return FDT_ADDR_T_NONE;
+
+ reg += index * (na + ns);
+
+ return fdt_translate_address((void *)gd->fdt_blob, offset, reg);
+}
+
+int meson_pinctrl_probe(struct udevice *dev)
+{
+ struct meson_pinctrl *priv = dev_get_priv(dev);
+ fdt_addr_t addr;
+ int node, gpio = -1, len;
+ int na, ns;
+
+ na = fdt_address_cells(gd->fdt_blob, dev->parent->of_offset);
+ if (na < 1) {
+ debug("bad #address-cells\n");
+ return -EINVAL;
+ }
+
+ ns = fdt_size_cells(gd->fdt_blob, dev->parent->of_offset);
+ if (ns < 1) {
+ debug("bad #size-cells\n");
+ return -EINVAL;
+ }
+
+ fdt_for_each_subnode(gd->fdt_blob, node, dev->of_offset) {
+ if (fdt_getprop(gd->fdt_blob, node, "gpio-controller", &len)) {
+ gpio = node;
+ break;
+ }
+ }
+
+ if (!gpio) {
+ debug("gpio node not found\n");
+ return -EINVAL;
+ }
+
+ addr = parse_address(gpio, "mux", na, ns);
+ if (addr == FDT_ADDR_T_NONE) {
+ debug("mux not found\n");
+ return -EINVAL;
+ }
+
+ priv->reg_mux = (void __iomem *)addr;
+ priv->data = (struct meson_pinctrl_data *)dev_get_driver_data(dev);
+
+ return 0;
+}