ARM: ep93xx: add regmap aux_dev

The following driver's should be instantiated by ep93xx syscon driver:

- reboot
- pinctrl
- clock

They all require access to DEVCFG register with a shared lock held, to
avoid conflict writing to swlocked parts of DEVCFG.

Provide common resources such as base, regmap and spinlock via auxiliary
bus framework.

Signed-off-by: Nikita Shubin <[e-mail]>
Tested-by: Alexander Sverdlin <[e-mail]>
Reviewed-by: Linus Walleij <[e-mail]>
Reviewed-by: Stephen Boyd <[e-mail]>
Acked-by: Vinod Koul <[e-mail]>
Signed-off-by: Arnd Bergmann <[e-mail]>

include/linux/soc/cirrus/ep93xx.h

···
 #define _SOC_EP93XX_H
 
 struct platform_device;
+struct regmap;
+struct spinlock_t;
+
+enum ep93xx_soc_model {
+	EP93XX_9301_SOC,
+	EP93XX_9307_SOC,
+	EP93XX_9312_SOC,
+};
+
+#include <linux/auxiliary_bus.h>
+#include <linux/compiler_types.h>
+#include <linux/container_of.h>
 
 #define EP93XX_CHIP_REV_D0	3
 #define EP93XX_CHIP_REV_D1	4
 #define EP93XX_CHIP_REV_E0	5
 #define EP93XX_CHIP_REV_E1	6
 #define EP93XX_CHIP_REV_E2	7
+
+struct ep93xx_regmap_adev {
+	struct auxiliary_device adev;
+	struct regmap *map;
+	void __iomem *base;
+	spinlock_t *lock;
+	void (*write)(struct regmap *map, spinlock_t *lock, unsigned int reg,
+		      unsigned int val);
+	void (*update_bits)(struct regmap *map, spinlock_t *lock,
+			    unsigned int reg, unsigned int mask, unsigned int val);
+};
+
+#define to_ep93xx_regmap_adev(_adev) \
+	container_of((_adev), struct ep93xx_regmap_adev, adev)
 
 #ifdef CONFIG_ARCH_EP93XX
 int ep93xx_pwm_acquire_gpio(struct platform_device *pdev);