pinctrl: Add pinmux & GPIO controller driver for a new SoC

Intel Lightning Mountain SoC has a pinmux controller & GPIO controller IP which
controls pin multiplexing & configuration including GPIO functions selection &
GPIO attributes configuration.

This IP is not based on & does not have anything in common with Chassis
specification. The pinctrl drivers under pinctrl/intel/* are all based upon
Chassis spec compliant pinctrl IPs. So this driver doesn't fit & can not use
pinctrl framework under pinctrl/intel/* and it requires a separate new driver.

Add a new GPIO & pin control framework based driver for this IP.

Signed-off-by: Rahul Tanwar <rahul.tanwar@linux.intel.com>
Link: https://lore.kernel.org/r/33e649758b70490f01724a887c490d5008c7656d.1573797249.git.rahul.tanwar@linux.intel.com
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/Kconfig

@@ -420,4 +420,22 @@ config PINCTRL_TB10X
 	depends on OF && ARC_PLAT_TB10X
 	select GPIOLIB
 
+config PINCTRL_EQUILIBRIUM
+	tristate "Generic pinctrl and GPIO driver for Intel Lightning Mountain SoC"
+	select PINMUX
+	select PINCONF
+	select GPIOLIB
+	select GPIO_GENERIC
+	select GPIOLIB_IRQCHIP
+	select GENERIC_PINCONF
+	select GENERIC_PINCTRL_GROUPS
+	select GENERIC_PINMUX_FUNCTIONS
+
+	help
+	  Equilibrium pinctrl driver is a pinctrl & GPIO driver for Intel Lightning
+	  Mountain network processor SoC that supports both the linux GPIO and pin
+	  control frameworks. It provides interfaces to setup pinmux, assign desired
+	  pin functions, configure GPIO attributes for LGM SoC pins. Pinmux and
+	  pinconf settings are retrieved from device tree.
+
 endif

drivers/pinctrl/Makefile

@@ -46,6 +46,7 @@ obj-$(CONFIG_PINCTRL_ZYNQ)	+= pinctrl-zynq.o
 obj-$(CONFIG_PINCTRL_INGENIC)	+= pinctrl-ingenic.o
 obj-$(CONFIG_PINCTRL_RK805)	+= pinctrl-rk805.o
 obj-$(CONFIG_PINCTRL_OCELOT)	+= pinctrl-ocelot.o
+obj-$(CONFIG_PINCTRL_EQUILIBRIUM)   += pinctrl-equilibrium.o
 
 obj-y				+= actions/
 obj-$(CONFIG_ARCH_ASPEED)	+= aspeed/

drivers/pinctrl/pinctrl-equilibrium.h

@@ -0,0 +1,144 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *  Copyright(c) 2019 Intel Corporation.
+ */
+
+#ifndef __PINCTRL_EQUILIBRIUM_H
+#define __PINCTRL_EQUILIBRIUM_H
+
+/* PINPAD register offset */
+#define REG_PMX_BASE	0x0	/* Port Multiplexer Control Register */
+#define REG_PUEN	0x80	/* PULL UP Enable Register */
+#define REG_PDEN	0x84	/* PULL DOWN Enable Register */
+#define REG_SRC		0x88	/* Slew Rate Control Register */
+#define REG_DCC0	0x8C	/* Drive Current Control Register 0 */
+#define REG_DCC1	0x90	/* Drive Current Control Register 1 */
+#define REG_OD		0x94	/* Open Drain Enable Register */
+#define REG_AVAIL	0x98	/* Pad Control Availability Register */
+#define DRV_CUR_PINS	16	/* Drive Current pin number per register */
+#define REG_DRCC(x)	(REG_DCC0 + (x) * 4) /* Driver current macro */
+
+/* GPIO register offset */
+#define GPIO_OUT	0x0	/* Data Output Register */
+#define GPIO_IN		0x4	/* Data Input Register */
+#define GPIO_DIR	0x8	/* Direction Register */
+#define GPIO_EXINTCR0	0x18	/* External Interrupt Control Register 0 */
+#define GPIO_EXINTCR1	0x1C	/* External Interrupt Control Register 1 */
+#define GPIO_IRNCR	0x20	/* IRN Capture Register */
+#define GPIO_IRNICR	0x24	/* IRN Interrupt Control Register */
+#define GPIO_IRNEN	0x28	/* IRN Interrupt Enable Register */
+#define GPIO_IRNCFG	0x2C	/* IRN Interrupt Configuration Register */
+#define GPIO_IRNRNSET	0x30	/* IRN Interrupt Enable Set Register */
+#define GPIO_IRNENCLR	0x34	/* IRN Interrupt Enable Clear Register */
+#define GPIO_OUTSET	0x40	/* Output Set Register */
+#define GPIO_OUTCLR	0x44	/* Output Clear Register */
+#define GPIO_DIRSET	0x48	/* Direction Set Register */
+#define GPIO_DIRCLR	0x4C	/* Direction Clear Register */
+
+/* parse given pin's driver current value */
+#define PARSE_DRV_CURRENT(val, pin) (((val) >> ((pin) * 2)) & 0x3)
+
+#define GPIO_EDGE_TRIG		0
+#define GPIO_LEVEL_TRIG		1
+#define GPIO_SINGLE_EDGE	0
+#define GPIO_BOTH_EDGE		1
+#define GPIO_POSITIVE_TRIG	0
+#define GPIO_NEGATIVE_TRIG	1
+
+#define EQBR_GPIO_MODE		0
+
+typedef enum {
+	OP_COUNT_NR_FUNCS,
+	OP_ADD_FUNCS,
+	OP_COUNT_NR_FUNC_GRPS,
+	OP_ADD_FUNC_GRPS,
+	OP_NONE,
+} funcs_util_ops;
+
+/**
+ * struct gpio_irq_type: gpio irq configuration
+ * @trig_type: level trigger or edge trigger
+ * @edge_type: sigle edge or both edge
+ * @logic_type: positive trigger or negative trigger
+ */
+struct gpio_irq_type {
+	unsigned int trig_type;
+	unsigned int edge_type;
+	unsigned int logic_type;
+};
+
+/**
+ * struct eqbr_pmx_func: represent a pin function.
+ * @name: name of the pin function, used to lookup the function.
+ * @groups: one or more names of pin groups that provide this function.
+ * @nr_groups: number of groups included in @groups.
+ */
+struct eqbr_pmx_func {
+	const char		*name;
+	const char		**groups;
+	unsigned int		nr_groups;
+};
+
+/**
+ * struct eqbr_pin_bank: represent a pin bank.
+ * @membase: base address of the pin bank register.
+ * @id: bank id, to idenify the unique bank.
+ * @pin_base: starting pin number of the pin bank.
+ * @nr_pins: number of the pins of the pin bank.
+ * @aval_pinmap: available pin bitmap of the pin bank.
+ */
+struct eqbr_pin_bank {
+	void __iomem		*membase;
+	unsigned int		id;
+	unsigned int		pin_base;
+	unsigned int		nr_pins;
+	u32			aval_pinmap;
+};
+
+/**
+ * struct eqbr_gpio_ctrl: represent a gpio controller.
+ * @node: device node of gpio controller.
+ * @bank: pointer to corresponding pin bank.
+ * @membase: base address of the gpio controller.
+ * @chip: gpio chip.
+ * @ic:   irq chip.
+ * @name: gpio chip name.
+ * @virq: irq number of the gpio chip to parent's irq domain.
+ * @lock: spin lock to protect gpio register write.
+ */
+struct eqbr_gpio_ctrl {
+	struct device_node	*node;
+	struct eqbr_pin_bank	*bank;
+	void __iomem		*membase;
+	struct gpio_chip	chip;
+	struct irq_chip		ic;
+	const char		*name;
+	unsigned int		virq;
+	raw_spinlock_t		lock; /* protect gpio register */
+};
+
+/**
+ * struct eqbr_pinctrl_drv_data:
+ * @dev: device instance representing the controller.
+ * @pctl_desc: pin controller descriptor.
+ * @pctl_dev: pin control class device
+ * @membase: base address of pin controller
+ * @pin_banks: list of pin banks of the driver.
+ * @nr_banks: number of pin banks.
+ * @gpio_ctrls: list of gpio controllers.
+ * @nr_gpio_ctrls: number of gpio controllers.
+ * @lock: protect pinctrl register write
+ */
+struct eqbr_pinctrl_drv_data {
+	struct device			*dev;
+	struct pinctrl_desc		pctl_desc;
+	struct pinctrl_dev		*pctl_dev;
+	void __iomem			*membase;
+	struct eqbr_pin_bank		*pin_banks;
+	unsigned int			nr_banks;
+	struct eqbr_gpio_ctrl		*gpio_ctrls;
+	unsigned int			nr_gpio_ctrls;
+	raw_spinlock_t			lock; /* protect pinpad register */
+};
+
+#endif /* __PINCTRL_EQUILIBRIUM_H */