1 files changed, 104 insertions, 0 deletions
diff --git a/drivers/pinctrl/meson/pinctrl-meson8-pmx.c b/drivers/pinctrl/meson/pinctrl-meson8-pmx.c
new file mode 100644
index 000000000..f767b6923
--- /dev/null
+++ b/drivers/pinctrl/meson/pinctrl-meson8-pmx.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * First generation of pinmux driver for Amlogic Meson SoCs
+ *
+ * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
+ * Copyright (C) 2017 Jerome Brunet  <jbrunet@baylibre.com>
+ */
+
+/* For this first generation of pinctrl driver every pinmux group can be
+ * enabled by a specific bit in the first register range. When all groups for
+ * a given pin are disabled the pin acts as a GPIO.
+ */
+#include <linux/device.h>
+#include <linux/regmap.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+
+#include "pinctrl-meson.h"
+#include "pinctrl-meson8-pmx.h"
+
+/**
+ * meson8_pmx_disable_other_groups() - disable other groups using a given pin
+ *
+ * @pc:		meson pin controller device
+ * @pin:	number of the pin
+ * @sel_group:	index of the selected group, or -1 if none
+ *
+ * The function disables all pinmux groups using a pin except the
+ * selected one. If @sel_group is -1 all groups are disabled, leaving
+ * the pin in GPIO mode.
+ */
+static void meson8_pmx_disable_other_groups(struct meson_pinctrl *pc,
+					    unsigned int pin, int sel_group)
+{
+	struct meson_pmx_group *group;
+	struct meson8_pmx_data *pmx_data;
+	int i, j;
+
+	for (i = 0; i < pc->data->num_groups; i++) {
+		group = &pc->data->groups[i];
+		pmx_data = (struct meson8_pmx_data *)group->data;
+		if (pmx_data->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 */
+				regmap_update_bits(pc->reg_mux,
+						   pmx_data->reg * 4,
+						   BIT(pmx_data->bit), 0);
+			}
+		}
+	}
+}
+
+static int meson8_pmx_set_mux(struct pinctrl_dev *pcdev, unsigned func_num,
+			      unsigned group_num)
+{
+	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
+	struct meson_pmx_func *func = &pc->data->funcs[func_num];
+	struct meson_pmx_group *group = &pc->data->groups[group_num];
+	struct meson8_pmx_data *pmx_data =
+		(struct meson8_pmx_data *)group->data;
+	int i, ret = 0;
+
+	dev_dbg(pc->dev, "enable function %s, group %s\n", func->name,
+		group->name);
+
+	/*
+	 * Disable groups using the same pin.
+	 * The selected group is not disabled to avoid glitches.
+	 */
+	for (i = 0; i < group->num_pins; i++)
+		meson8_pmx_disable_other_groups(pc, group->pins[i], group_num);
+
+	/* Function 0 (GPIO) doesn't need any additional setting */
+	if (func_num)
+		ret = regmap_update_bits(pc->reg_mux, pmx_data->reg * 4,
+					 BIT(pmx_data->bit),
+					 BIT(pmx_data->bit));
+
+	return ret;
+}
+
+static int meson8_pmx_request_gpio(struct pinctrl_dev *pcdev,
+				   struct pinctrl_gpio_range *range,
+				   unsigned offset)
+{
+	struct meson_pinctrl *pc = pinctrl_dev_get_drvdata(pcdev);
+
+	meson8_pmx_disable_other_groups(pc, offset, -1);
+
+	return 0;
+}
+
+const struct pinmux_ops meson8_pmx_ops = {
+	.set_mux = meson8_pmx_set_mux,
+	.get_functions_count = meson_pmx_get_funcs_count,
+	.get_function_name = meson_pmx_get_func_name,
+	.get_function_groups = meson_pmx_get_groups,
+	.gpio_request_enable = meson8_pmx_request_gpio,
+};
+EXPORT_SYMBOL_GPL(meson8_pmx_ops);
+MODULE_LICENSE("GPL v2");