pinctrl: meson: add GPIO support

This commit adds GPIO support to the Amlogic Meson pin controller
driver, based on code from Linux kernel.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>

1 files changed, 63 insertions, 0 deletions

diff --git a/drivers/pinctrl/meson/pinctrl-meson.h b/drivers/pinctrl/meson/pinctrl-meson.h
index 4127a60f48..90d2369842 100644
--- a/drivers/pinctrl/meson/pinctrl-meson.h
+++ b/drivers/pinctrl/meson/pinctrl-meson.h
@@ -28,15 +28,64 @@ struct meson_pinctrl_data {
 	const char *name;
 	struct meson_pmx_group *groups;
 	struct meson_pmx_func *funcs;
+	struct meson_bank *banks;
 	unsigned int pin_base;
 	unsigned int num_pins;
 	unsigned int num_groups;
 	unsigned int num_funcs;
+	unsigned int num_banks;
 };
 
 struct meson_pinctrl {
 	struct meson_pinctrl_data *data;
 	void __iomem *reg_mux;
+	void __iomem *reg_gpio;
+};
+
+/**
+ * struct meson_reg_desc - a register descriptor
+ *
+ * @reg:	register offset in the regmap
+ * @bit:	bit index in register
+ *
+ * The structure describes the information needed to control pull,
+ * pull-enable, direction, etc. for a single pin
+ */
+struct meson_reg_desc {
+	unsigned int reg;
+	unsigned int bit;
+};
+
+/**
+ * enum meson_reg_type - type of registers encoded in @meson_reg_desc
+ */
+enum meson_reg_type {
+	REG_PULLEN,
+	REG_PULL,
+	REG_DIR,
+	REG_OUT,
+	REG_IN,
+	NUM_REG,
+};
+
+/**
+ * struct meson bank
+ *
+ * @name:	bank name
+ * @first:	first pin of the bank
+ * @last:	last pin of the bank
+ * @regs:	array of register descriptors
+ *
+ * A bank represents a set of pins controlled by a contiguous set of
+ * bits in the domain registers. The structure specifies which bits in
+ * the regmap control the different functionalities. Each member of
+ * the @regs array refers to the first pin of the bank.
+ */
+struct meson_bank {
+	const char *name;
+	unsigned int first;
+	unsigned int last;
+	struct meson_reg_desc regs[NUM_REG];
 };
 
 #define PIN(x, b)	(b + x)
@@ -65,6 +114,20 @@ struct meson_pinctrl {
 		.num_groups = ARRAY_SIZE(fn ## _groups),		\
 	}
 
+#define BANK(n, f, l, per, peb, pr, pb, dr, db, or, ob, ir, ib)		\
+	{								\
+		.name	= n,						\
+		.first	= f,						\
+		.last	= l,						\
+		.regs	= {						\
+			[REG_PULLEN]	= { per, peb },			\
+			[REG_PULL]	= { pr, pb },			\
+			[REG_DIR]	= { dr, db },			\
+			[REG_OUT]	= { or, ob },			\
+			[REG_IN]	= { ir, ib },			\
+		},							\
+	 }
+
 #define MESON_PIN(x, b) PINCTRL_PIN(PIN(x, b), #x)
 
 extern const struct pinctrl_ops meson_pinctrl_ops;