[PATCH V4 1/9] pinctrl: imx: Support building SCU pinctrl driver as module

[Anson Huang <Anson.Huang@xxxxxxx>]

To support building i.MX SCU pinctrl driver as module, below things
need to be changed:

    - Export SCU related functions and use "IS_ENABLED" instead of
      "ifdef" to support SCU pinctrl driver user and itself to be
      built as module;
    - Use function callbacks for SCU related functions in pinctrl-imx.c
      in order to support the scenario of PINCTRL_IMX is built in
      while PINCTRL_IMX_SCU is built as module;
    - All drivers using SCU pinctrl driver need to initialize the
      SCU related function callback;
    - Change PINCTR_IMX_SCU to tristate.

With above changes, i.MX SCU pinctrl driver can be built as module.

Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
---
Changes since V3:
	- change config dependency back to original;
	- use function callbacks for SCU related functions in pinctrl-imx.c
	  to support the scenario of PINCTRL_IMX is built in while
	  PINCTRL_IMX_SCU is built as module;
	- initialize SCU related functions callback in i.MX8QM/QXP/DXL;
	- remove unused SCU related stub functions in pinctrl-imx.h.
---
 drivers/pinctrl/freescale/Kconfig           |  2 +-
 drivers/pinctrl/freescale/pinctrl-imx.c     | 18 ++++-----
 drivers/pinctrl/freescale/pinctrl-imx.h     | 57 ++++++++++++-----------------
 drivers/pinctrl/freescale/pinctrl-imx8dxl.c |  3 ++
 drivers/pinctrl/freescale/pinctrl-imx8qm.c  |  3 ++
 drivers/pinctrl/freescale/pinctrl-imx8qxp.c |  3 ++
 drivers/pinctrl/freescale/pinctrl-scu.c     |  6 +++
 7 files changed, 48 insertions(+), 44 deletions(-)

diff --git a/drivers/pinctrl/freescale/Kconfig b/drivers/pinctrl/freescale/Kconfig
index 4ca44dd..a3a30f1d 100644
--- a/drivers/pinctrl/freescale/Kconfig
+++ b/drivers/pinctrl/freescale/Kconfig
@@ -7,7 +7,7 @@ config PINCTRL_IMX
 	select REGMAP
 
 config PINCTRL_IMX_SCU
-	bool
+	tristate "IMX SCU pinctrl driver"
 	depends on IMX_SCU
 	select PINCTRL_IMX
 
diff --git a/drivers/pinctrl/freescale/pinctrl-imx.c b/drivers/pinctrl/freescale/pinctrl-imx.c
index cb7e0f0..c1faae1 100644
--- a/drivers/pinctrl/freescale/pinctrl-imx.c
+++ b/drivers/pinctrl/freescale/pinctrl-imx.c
@@ -372,8 +372,8 @@ static int imx_pinconf_get(struct pinctrl_dev *pctldev,
 	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
 	const struct imx_pinctrl_soc_info *info = ipctl->info;
 
-	if (info->flags & IMX_USE_SCU)
-		return imx_pinconf_get_scu(pctldev, pin_id, config);
+	if ((info->flags & IMX_USE_SCU) && info->imx_pinconf_get)
+		return info->imx_pinconf_get(pctldev, pin_id, config);
 	else
 		return imx_pinconf_get_mmio(pctldev, pin_id, config);
 }
@@ -422,8 +422,8 @@ static int imx_pinconf_set(struct pinctrl_dev *pctldev,
 	struct imx_pinctrl *ipctl = pinctrl_dev_get_drvdata(pctldev);
 	const struct imx_pinctrl_soc_info *info = ipctl->info;
 
-	if (info->flags & IMX_USE_SCU)
-		return imx_pinconf_set_scu(pctldev, pin_id,
+	if ((info->flags & IMX_USE_SCU) && info->imx_pinconf_set)
+		return info->imx_pinconf_set(pctldev, pin_id,
 					   configs, num_configs);
 	else
 		return imx_pinconf_set_mmio(pctldev, pin_id,
@@ -439,8 +439,8 @@ static void imx_pinconf_dbg_show(struct pinctrl_dev *pctldev,
 	unsigned long config;
 	int ret;
 
-	if (info->flags & IMX_USE_SCU) {
-		ret = imx_pinconf_get_scu(pctldev, pin_id, &config);
+	if ((info->flags & IMX_USE_SCU) && info->imx_pinconf_get) {
+		ret = info->imx_pinconf_get(pctldev, pin_id, &config);
 		if (ret) {
 			dev_err(ipctl->dev, "failed to get %s pinconf\n",
 				pin_get_name(pctldev, pin_id));
@@ -628,9 +628,9 @@ static int imx_pinctrl_parse_groups(struct device_node *np,
 
 	for (i = 0; i < grp->num_pins; i++) {
 		pin = &((struct imx_pin *)(grp->data))[i];
-		if (info->flags & IMX_USE_SCU)
-			imx_pinctrl_parse_pin_scu(ipctl, &grp->pins[i],
-						  pin, &list);
+		if ((info->flags & IMX_USE_SCU) && info->imx_pinctrl_parse_pin)
+			info->imx_pinctrl_parse_pin(ipctl, &grp->pins[i],
+						    pin, &list);
 		else
 			imx_pinctrl_parse_pin_mmio(ipctl, &grp->pins[i],
 						   pin, &list, np);
diff --git a/drivers/pinctrl/freescale/pinctrl-imx.h b/drivers/pinctrl/freescale/pinctrl-imx.h
index 333d32b..bdb86c2 100644
--- a/drivers/pinctrl/freescale/pinctrl-imx.h
+++ b/drivers/pinctrl/freescale/pinctrl-imx.h
@@ -75,6 +75,21 @@ struct imx_cfg_params_decode {
 	bool invert;
 };
 
+/**
+ * @dev: a pointer back to containing device
+ * @base: the offset to the controller in virtual memory
+ */
+struct imx_pinctrl {
+	struct device *dev;
+	struct pinctrl_dev *pctl;
+	void __iomem *base;
+	void __iomem *input_sel_base;
+	const struct imx_pinctrl_soc_info *info;
+	struct imx_pin_reg *pin_regs;
+	unsigned int group_index;
+	struct mutex mutex;
+};
+
 struct imx_pinctrl_soc_info {
 	const struct pinctrl_pin_desc *pins;
 	unsigned int npins;
@@ -98,21 +113,13 @@ struct imx_pinctrl_soc_info {
 				  struct pinctrl_gpio_range *range,
 				  unsigned offset,
 				  bool input);
-};
-
-/**
- * @dev: a pointer back to containing device
- * @base: the offset to the controller in virtual memory
- */
-struct imx_pinctrl {
-	struct device *dev;
-	struct pinctrl_dev *pctl;
-	void __iomem *base;
-	void __iomem *input_sel_base;
-	const struct imx_pinctrl_soc_info *info;
-	struct imx_pin_reg *pin_regs;
-	unsigned int group_index;
-	struct mutex mutex;
+	int (*imx_pinconf_get)(struct pinctrl_dev *pctldev, unsigned int pin_id,
+			       unsigned long *config);
+	int (*imx_pinconf_set)(struct pinctrl_dev *pctldev, unsigned int pin_id,
+			       unsigned long *configs, unsigned int num_configs);
+	void (*imx_pinctrl_parse_pin)(struct imx_pinctrl *ipctl,
+				      unsigned int *pin_id, struct imx_pin *pin,
+				      const __be32 **list_p);
 };
 
 #define IMX_CFG_PARAMS_DECODE(p, m, o) \
@@ -137,7 +144,7 @@ struct imx_pinctrl {
 int imx_pinctrl_probe(struct platform_device *pdev,
 			const struct imx_pinctrl_soc_info *info);
 
-#ifdef CONFIG_PINCTRL_IMX_SCU
+#if IS_ENABLED(CONFIG_PINCTRL_IMX_SCU)
 #define BM_PAD_CTL_GP_ENABLE		BIT(30)
 #define BM_PAD_CTL_IFMUX_ENABLE		BIT(31)
 #define BP_PAD_CTL_IFMUX		27
@@ -150,23 +157,5 @@ int imx_pinconf_set_scu(struct pinctrl_dev *pctldev, unsigned pin_id,
 void imx_pinctrl_parse_pin_scu(struct imx_pinctrl *ipctl,
 			       unsigned int *pin_id, struct imx_pin *pin,
 			       const __be32 **list_p);
-#else
-static inline int imx_pinconf_get_scu(struct pinctrl_dev *pctldev,
-				      unsigned pin_id, unsigned long *config)
-{
-	return -EINVAL;
-}
-static inline int imx_pinconf_set_scu(struct pinctrl_dev *pctldev,
-				      unsigned pin_id, unsigned long *configs,
-				      unsigned num_configs)
-{
-	return -EINVAL;
-}
-static inline void imx_pinctrl_parse_pin_scu(struct imx_pinctrl *ipctl,
-					    unsigned int *pin_id,
-					    struct imx_pin *pin,
-					    const __be32 **list_p)
-{
-}
 #endif
 #endif /* __DRIVERS_PINCTRL_IMX_H */
diff --git a/drivers/pinctrl/freescale/pinctrl-imx8dxl.c b/drivers/pinctrl/freescale/pinctrl-imx8dxl.c
index 7f32e57..be3b09e 100644
--- a/drivers/pinctrl/freescale/pinctrl-imx8dxl.c
+++ b/drivers/pinctrl/freescale/pinctrl-imx8dxl.c
@@ -159,6 +159,9 @@ static struct imx_pinctrl_soc_info imx8dxl_pinctrl_info = {
 	.pins = imx8dxl_pinctrl_pads,
 	.npins = ARRAY_SIZE(imx8dxl_pinctrl_pads),
 	.flags = IMX_USE_SCU,
+	.imx_pinconf_get = imx_pinconf_get_scu,
+	.imx_pinconf_set = imx_pinconf_set_scu,
+	.imx_pinctrl_parse_pin = imx_pinctrl_parse_pin_scu,
 };
 
 static const struct of_device_id imx8dxl_pinctrl_of_match[] = {
diff --git a/drivers/pinctrl/freescale/pinctrl-imx8qm.c b/drivers/pinctrl/freescale/pinctrl-imx8qm.c
index 0b6029b..9ba3249 100644
--- a/drivers/pinctrl/freescale/pinctrl-imx8qm.c
+++ b/drivers/pinctrl/freescale/pinctrl-imx8qm.c
@@ -292,6 +292,9 @@ static const struct imx_pinctrl_soc_info imx8qm_pinctrl_info = {
 	.pins = imx8qm_pinctrl_pads,
 	.npins = ARRAY_SIZE(imx8qm_pinctrl_pads),
 	.flags = IMX_USE_SCU,
+	.imx_pinconf_get = imx_pinconf_get_scu,
+	.imx_pinconf_set = imx_pinconf_set_scu,
+	.imx_pinctrl_parse_pin = imx_pinctrl_parse_pin_scu,
 };
 
 static const struct of_device_id imx8qm_pinctrl_of_match[] = {
diff --git a/drivers/pinctrl/freescale/pinctrl-imx8qxp.c b/drivers/pinctrl/freescale/pinctrl-imx8qxp.c
index 1131dc3..05906b9 100644
--- a/drivers/pinctrl/freescale/pinctrl-imx8qxp.c
+++ b/drivers/pinctrl/freescale/pinctrl-imx8qxp.c
@@ -198,6 +198,9 @@ static struct imx_pinctrl_soc_info imx8qxp_pinctrl_info = {
 	.pins = imx8qxp_pinctrl_pads,
 	.npins = ARRAY_SIZE(imx8qxp_pinctrl_pads),
 	.flags = IMX_USE_SCU,
+	.imx_pinconf_get = imx_pinconf_get_scu,
+	.imx_pinconf_set = imx_pinconf_set_scu,
+	.imx_pinctrl_parse_pin = imx_pinctrl_parse_pin_scu,
 };
 
 static const struct of_device_id imx8qxp_pinctrl_of_match[] = {
diff --git a/drivers/pinctrl/freescale/pinctrl-scu.c b/drivers/pinctrl/freescale/pinctrl-scu.c
index 23cf04b..35efd5c 100644
--- a/drivers/pinctrl/freescale/pinctrl-scu.c
+++ b/drivers/pinctrl/freescale/pinctrl-scu.c
@@ -7,6 +7,7 @@
 
 #include <linux/err.h>
 #include <linux/firmware/imx/sci.h>
+#include <linux/module.h>
 #include <linux/of_address.h>
 #include <linux/pinctrl/pinctrl.h>
 #include <linux/platform_device.h>
@@ -41,6 +42,7 @@ int imx_pinctrl_sc_ipc_init(struct platform_device *pdev)
 {
 	return imx_scu_get_handle(&pinctrl_ipc_handle);
 }
+EXPORT_SYMBOL_GPL(imx_pinctrl_sc_ipc_init);
 
 int imx_pinconf_get_scu(struct pinctrl_dev *pctldev, unsigned pin_id,
 			unsigned long *config)
@@ -66,6 +68,7 @@ int imx_pinconf_get_scu(struct pinctrl_dev *pctldev, unsigned pin_id,
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(imx_pinconf_get_scu);
 
 int imx_pinconf_set_scu(struct pinctrl_dev *pctldev, unsigned pin_id,
 			unsigned long *configs, unsigned num_configs)
@@ -101,6 +104,7 @@ int imx_pinconf_set_scu(struct pinctrl_dev *pctldev, unsigned pin_id,
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(imx_pinconf_set_scu);
 
 void imx_pinctrl_parse_pin_scu(struct imx_pinctrl *ipctl,
 			       unsigned int *pin_id, struct imx_pin *pin,
@@ -119,3 +123,5 @@ void imx_pinctrl_parse_pin_scu(struct imx_pinctrl *ipctl,
 	dev_dbg(ipctl->dev, "%s: 0x%x 0x%08lx", info->pins[pin->pin].name,
 		pin_scu->mux_mode, pin_scu->config);
 }
+EXPORT_SYMBOL_GPL(imx_pinctrl_parse_pin_scu);
+MODULE_LICENSE("GPL v2");
-- 
2.7.4