gpio: nomadik: extract GPIO platform driver from drivers/pinctrl/nomadik/

Previously, drivers/pinctrl/nomadik/pinctrl-nomadik.c registered two
platform drivers: pinctrl & GPIO. Move the GPIO aspect to the
drivers/gpio/ folder, as would be expected.

Both drivers are intertwined for a reason; pinctrl requires access to
GPIO registers for pinmuxing, pull-disable, disabling interrupts while
setting the muxing and wakeup control. Information sharing is done
through a shared array containing GPIO chips and a few helper
functions. That shared array is not touched from gpio-nomadik when
CONFIG_PINCTRL_NOMADIK is not defined.

Make no change to the code that moved into gpio-nomadik; there should be
no behavior change following. A few functions are shared and header
comments are added. Checkpatch warnings are addressed. NUM_BANKS is
renamed to NMK_MAX_BANKS.

It is supported to compile gpio-nomadik without pinctrl-nomadik. The
opposite is not true.

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
Link: https://lore.kernel.org/r/20240228-mbly-gpio-v2-6-3ba757474006@bootlin.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 276 insertions, 0 deletions

diff --git a/include/linux/gpio/gpio-nomadik.h b/include/linux/gpio/gpio-nomadik.h
new file mode 100644
index 000000000000..0166ddb71f43
--- /dev/null
+++ b/include/linux/gpio/gpio-nomadik.h
@@ -0,0 +1,276 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_GPIO_NOMADIK_H
+#define __LINUX_GPIO_NOMADIK_H
+
+/* Package definitions */
+#define PINCTRL_NMK_STN8815	0
+#define PINCTRL_NMK_DB8500	1
+
+#define GPIO_BLOCK_SHIFT 5
+#define NMK_GPIO_PER_CHIP BIT(GPIO_BLOCK_SHIFT)
+#define NMK_MAX_BANKS DIV_ROUND_UP(512, NMK_GPIO_PER_CHIP)
+
+/* Register in the logic block */
+#define NMK_GPIO_DAT	0x00
+#define NMK_GPIO_DATS	0x04
+#define NMK_GPIO_DATC	0x08
+#define NMK_GPIO_PDIS	0x0c
+#define NMK_GPIO_DIR	0x10
+#define NMK_GPIO_DIRS	0x14
+#define NMK_GPIO_DIRC	0x18
+#define NMK_GPIO_SLPC	0x1c
+#define NMK_GPIO_AFSLA	0x20
+#define NMK_GPIO_AFSLB	0x24
+#define NMK_GPIO_LOWEMI	0x28
+
+#define NMK_GPIO_RIMSC	0x40
+#define NMK_GPIO_FIMSC	0x44
+#define NMK_GPIO_IS	0x48
+#define NMK_GPIO_IC	0x4c
+#define NMK_GPIO_RWIMSC	0x50
+#define NMK_GPIO_FWIMSC	0x54
+#define NMK_GPIO_WKS	0x58
+/* These appear in DB8540 and later ASICs */
+#define NMK_GPIO_EDGELEVEL 0x5C
+#define NMK_GPIO_LEVEL	0x60
+
+/* Pull up/down values */
+enum nmk_gpio_pull {
+	NMK_GPIO_PULL_NONE,
+	NMK_GPIO_PULL_UP,
+	NMK_GPIO_PULL_DOWN,
+};
+
+/* Sleep mode */
+enum nmk_gpio_slpm {
+	NMK_GPIO_SLPM_INPUT,
+	NMK_GPIO_SLPM_WAKEUP_ENABLE = NMK_GPIO_SLPM_INPUT,
+	NMK_GPIO_SLPM_NOCHANGE,
+	NMK_GPIO_SLPM_WAKEUP_DISABLE = NMK_GPIO_SLPM_NOCHANGE,
+};
+
+struct nmk_gpio_chip {
+	struct gpio_chip chip;
+	void __iomem *addr;
+	struct clk *clk;
+	unsigned int bank;
+	void (*set_ioforce)(bool enable);
+	spinlock_t lock;
+	bool sleepmode;
+	/* Keep track of configured edges */
+	u32 edge_rising;
+	u32 edge_falling;
+	u32 real_wake;
+	u32 rwimsc;
+	u32 fwimsc;
+	u32 rimsc;
+	u32 fimsc;
+	u32 pull_up;
+	u32 lowemi;
+};
+
+/* Alternate functions: function C is set in hw by setting both A and B */
+#define NMK_GPIO_ALT_GPIO	0
+#define NMK_GPIO_ALT_A	1
+#define NMK_GPIO_ALT_B	2
+#define NMK_GPIO_ALT_C	(NMK_GPIO_ALT_A | NMK_GPIO_ALT_B)
+
+#define NMK_GPIO_ALT_CX_SHIFT 2
+#define NMK_GPIO_ALT_C1	((1<<NMK_GPIO_ALT_CX_SHIFT) | NMK_GPIO_ALT_C)
+#define NMK_GPIO_ALT_C2	((2<<NMK_GPIO_ALT_CX_SHIFT) | NMK_GPIO_ALT_C)
+#define NMK_GPIO_ALT_C3	((3<<NMK_GPIO_ALT_CX_SHIFT) | NMK_GPIO_ALT_C)
+#define NMK_GPIO_ALT_C4	((4<<NMK_GPIO_ALT_CX_SHIFT) | NMK_GPIO_ALT_C)
+
+#define PRCM_GPIOCR_ALTCX(pin_num,\
+	altc1_used, altc1_ri, altc1_cb,\
+	altc2_used, altc2_ri, altc2_cb,\
+	altc3_used, altc3_ri, altc3_cb,\
+	altc4_used, altc4_ri, altc4_cb)\
+{\
+	.pin = pin_num,\
+	.altcx[PRCM_IDX_GPIOCR_ALTC1] = {\
+		.used = altc1_used,\
+		.reg_index = altc1_ri,\
+		.control_bit = altc1_cb\
+	},\
+	.altcx[PRCM_IDX_GPIOCR_ALTC2] = {\
+		.used = altc2_used,\
+		.reg_index = altc2_ri,\
+		.control_bit = altc2_cb\
+	},\
+	.altcx[PRCM_IDX_GPIOCR_ALTC3] = {\
+		.used = altc3_used,\
+		.reg_index = altc3_ri,\
+		.control_bit = altc3_cb\
+	},\
+	.altcx[PRCM_IDX_GPIOCR_ALTC4] = {\
+		.used = altc4_used,\
+		.reg_index = altc4_ri,\
+		.control_bit = altc4_cb\
+	},\
+}
+
+/**
+ * enum prcm_gpiocr_reg_index
+ * Used to reference an PRCM GPIOCR register address.
+ */
+enum prcm_gpiocr_reg_index {
+	PRCM_IDX_GPIOCR1,
+	PRCM_IDX_GPIOCR2,
+	PRCM_IDX_GPIOCR3
+};
+/**
+ * enum prcm_gpiocr_altcx_index
+ * Used to reference an Other alternate-C function.
+ */
+enum prcm_gpiocr_altcx_index {
+	PRCM_IDX_GPIOCR_ALTC1,
+	PRCM_IDX_GPIOCR_ALTC2,
+	PRCM_IDX_GPIOCR_ALTC3,
+	PRCM_IDX_GPIOCR_ALTC4,
+	PRCM_IDX_GPIOCR_ALTC_MAX,
+};
+
+/**
+ * struct prcm_gpio_altcx - Other alternate-C function
+ * @used: other alternate-C function availability
+ * @reg_index: PRCM GPIOCR register index used to control the function
+ * @control_bit: PRCM GPIOCR bit used to control the function
+ */
+struct prcm_gpiocr_altcx {
+	bool used:1;
+	u8 reg_index:2;
+	u8 control_bit:5;
+} __packed;
+
+/**
+ * struct prcm_gpio_altcx_pin_desc - Other alternate-C pin
+ * @pin: The pin number
+ * @altcx: array of other alternate-C[1-4] functions
+ */
+struct prcm_gpiocr_altcx_pin_desc {
+	unsigned short pin;
+	struct prcm_gpiocr_altcx altcx[PRCM_IDX_GPIOCR_ALTC_MAX];
+};
+
+/**
+ * struct nmk_function - Nomadik pinctrl mux function
+ * @name: The name of the function, exported to pinctrl core.
+ * @groups: An array of pin groups that may select this function.
+ * @ngroups: The number of entries in @groups.
+ */
+struct nmk_function {
+	const char *name;
+	const char * const *groups;
+	unsigned int ngroups;
+};
+
+/**
+ * struct nmk_pingroup - describes a Nomadik pin group
+ * @grp: Generic data of the pin group (name and pins)
+ * @altsetting: the altsetting to apply to all pins in this group to
+ *	configure them to be used by a function
+ */
+struct nmk_pingroup {
+	struct pingroup grp;
+	int altsetting;
+};
+
+#define NMK_PIN_GROUP(a, b)							\
+	{									\
+		.grp = PINCTRL_PINGROUP(#a, a##_pins, ARRAY_SIZE(a##_pins)),	\
+		.altsetting = b,						\
+	}
+
+/**
+ * struct nmk_pinctrl_soc_data - Nomadik pin controller per-SoC configuration
+ * @pins:	An array describing all pins the pin controller affects.
+ *		All pins which are also GPIOs must be listed first within the
+ *		array, and be numbered identically to the GPIO controller's
+ *		numbering.
+ * @npins:	The number of entries in @pins.
+ * @functions:	The functions supported on this SoC.
+ * @nfunction:	The number of entries in @functions.
+ * @groups:	An array describing all pin groups the pin SoC supports.
+ * @ngroups:	The number of entries in @groups.
+ * @altcx_pins:	The pins that support Other alternate-C function on this SoC
+ * @npins_altcx: The number of Other alternate-C pins
+ * @prcm_gpiocr_registers: The array of PRCM GPIOCR registers on this SoC
+ */
+struct nmk_pinctrl_soc_data {
+	const struct pinctrl_pin_desc *pins;
+	unsigned int npins;
+	const struct nmk_function *functions;
+	unsigned int nfunctions;
+	const struct nmk_pingroup *groups;
+	unsigned int ngroups;
+	const struct prcm_gpiocr_altcx_pin_desc *altcx_pins;
+	unsigned int npins_altcx;
+	const u16 *prcm_gpiocr_registers;
+};
+
+#ifdef CONFIG_PINCTRL_STN8815
+
+void nmk_pinctrl_stn8815_init(const struct nmk_pinctrl_soc_data **soc);
+
+#else
+
+static inline void
+nmk_pinctrl_stn8815_init(const struct nmk_pinctrl_soc_data **soc)
+{
+}
+
+#endif
+
+#ifdef CONFIG_PINCTRL_DB8500
+
+void nmk_pinctrl_db8500_init(const struct nmk_pinctrl_soc_data **soc);
+
+#else
+
+static inline void
+nmk_pinctrl_db8500_init(const struct nmk_pinctrl_soc_data **soc)
+{
+}
+
+#endif
+
+#ifdef CONFIG_PINCTRL_DB8540
+
+void nmk_pinctrl_db8540_init(const struct nmk_pinctrl_soc_data **soc);
+
+#else
+
+static inline void
+nmk_pinctrl_db8540_init(const struct nmk_pinctrl_soc_data **soc)
+{
+}
+
+#endif
+
+struct platform_device;
+
+/*
+ * Symbols declared in gpio-nomadik used by pinctrl-nomadik. If pinctrl-nomadik
+ * is enabled, then gpio-nomadik is enabled as well; the reverse if not always
+ * true.
+ */
+void nmk_gpio_dbg_show_one(struct seq_file *s, struct pinctrl_dev *pctldev,
+			   struct gpio_chip *chip, unsigned int offset,
+			   unsigned int gpio);
+void __nmk_gpio_make_output(struct nmk_gpio_chip *nmk_chip,
+			    unsigned int offset, int val);
+void __nmk_gpio_set_slpm(struct nmk_gpio_chip *nmk_chip, unsigned int offset,
+			 enum nmk_gpio_slpm mode);
+struct nmk_gpio_chip *nmk_gpio_populate_chip(struct device_node *np,
+					     struct platform_device *pdev);
+
+/* Symbols declared in pinctrl-nomadik used by gpio-nomadik. */
+#ifdef CONFIG_PINCTRL_NOMADIK
+extern struct nmk_gpio_chip *nmk_gpio_chips[NMK_MAX_BANKS];
+extern spinlock_t nmk_gpio_slpm_lock;
+int __maybe_unused nmk_prcm_gpiocr_get_mode(struct pinctrl_dev *pctldev,
+					    int gpio);
+#endif
+
+#endif /* __LINUX_GPIO_NOMADIK_H */