gpiolib: split of_mm_gpio_chip out of linux/of_gpio.h

This is a rarely used feature that has nothing to do with the
client-side of_gpio.h.

Split it out with a separate header file and Kconfig option
so it can be removed on its own timeline aside from removing
the of_gpio consumer interfaces.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

7 files changed, 28 insertions, 9 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index df82fb7eb0eb..2b72a7a7084a 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -39,6 +39,14 @@ config GPIOLIB_IRQCHIP
 	select IRQ_DOMAIN
 	bool
 
+config OF_GPIO_MM_GPIOCHIP
+	bool
+	help
+	  This adds support for the legacy 'struct of_mm_gpio_chip' interface
+	  from PowerPC. Existing drivers using this interface need to select
+	  this symbol, but new drivers should use the generic gpio-regmap
+	  infrastructure instead.
+
 config DEBUG_GPIO
 	bool "Debug GPIO calls"
 	depends on DEBUG_KERNEL
@@ -131,6 +139,7 @@ config GPIO_ALTERA
 	tristate "Altera GPIO"
 	depends on OF_GPIO
 	select GPIOLIB_IRQCHIP
+	select OF_GPIO_MM_GPIOCHIP
 	help
 	  Say Y or M here to build support for the Altera PIO device.
 
@@ -403,6 +412,7 @@ config GPIO_MENZ127
 config GPIO_MM_LANTIQ
 	bool "Lantiq Memory mapped GPIOs"
 	depends on LANTIQ && SOC_XWAY
+	select OF_GPIO_MM_GPIOCHIP
 	help
 	  This enables support for memory mapped GPIOs on the External Bus Unit
 	  (EBU) found on Lantiq SoCs. The GPIOs are output only as they are
@@ -411,6 +421,7 @@ config GPIO_MM_LANTIQ
 config GPIO_MPC5200
 	def_bool y
 	depends on PPC_MPC52xx
+	select OF_GPIO_MM_GPIOCHIP
 
 config GPIO_MPC8XXX
 	bool "MPC512x/MPC8xxx/QorIQ GPIO support"
diff --git a/drivers/gpio/TODO b/drivers/gpio/TODO
index 68ada1066941..189c3abe7e79 100644
--- a/drivers/gpio/TODO
+++ b/drivers/gpio/TODO
@@ -59,11 +59,6 @@ the device tree back-end. It is legacy and should not be used in new code.
 
 Work items:
 
-- Get rid of struct of_mm_gpio_chip altogether: use the generic  MMIO
-  GPIO for all current users (see below). Delete struct of_mm_gpio_chip,
-  to_of_mm_gpio_chip(), of_mm_gpiochip_add_data(), of_mm_gpiochip_remove()
-  from the kernel.
-
 - Change all consumer drivers that #include <linux/of_gpio.h> to
   #include <linux/gpio/consumer.h> and stop doing custom parsing of the
   GPIO lines from the device tree. This can be tricky and often ivolves
@@ -81,6 +76,16 @@ Work items:
   uses <linux/gpio/consumer.h> or <linux/gpio/driver.h> instead.
 
 
+Get rid of <linux/gpio/legacy-of-mm-gpiochip.h>
+
+Work items:
+
+- Get rid of struct of_mm_gpio_chip altogether: use the generic  MMIO
+  GPIO for all current users (see below). Delete struct of_mm_gpio_chip,
+  to_of_mm_gpio_chip(), of_mm_gpiochip_add_data(), of_mm_gpiochip_remove(),
+  CONFIG_OF_GPIO_MM_GPIOCHIP from the kernel.
+
+
 Get rid of <linux/gpio.h>
 
 This legacy header is a one stop shop for anything GPIO is closely tied
diff --git a/drivers/gpio/gpio-altera.c b/drivers/gpio/gpio-altera.c
index b59fae993626..99e137f8097e 100644
--- a/drivers/gpio/gpio-altera.c
+++ b/drivers/gpio/gpio-altera.c
@@ -7,7 +7,7 @@
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/gpio/driver.h>
-#include <linux/of_gpio.h> /* For of_mm_gpio_chip */
+#include <linux/gpio/legacy-of-mm-gpiochip.h>
 #include <linux/platform_device.h>
 
 #define ALTERA_GPIO_MAX_NGPIO		32
diff --git a/drivers/gpio/gpio-mm-lantiq.c b/drivers/gpio/gpio-mm-lantiq.c
index 538e31fe8903..27ff84c5d162 100644
--- a/drivers/gpio/gpio-mm-lantiq.c
+++ b/drivers/gpio/gpio-mm-lantiq.c
@@ -10,8 +10,8 @@
 #include <linux/platform_device.h>
 #include <linux/mutex.h>
 #include <linux/gpio/driver.h>
+#include <linux/gpio/legacy-of-mm-gpiochip.h.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>
 #include <linux/io.h>
 #include <linux/slab.h>
 
diff --git a/drivers/gpio/gpio-mpc5200.c b/drivers/gpio/gpio-mpc5200.c
index 000494e0c533..3b0bfff8c778 100644
--- a/drivers/gpio/gpio-mpc5200.c
+++ b/drivers/gpio/gpio-mpc5200.c
@@ -8,7 +8,7 @@
 #include <linux/of.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
-#include <linux/of_gpio.h>
+#include <linux/gpio/legacy-of-mm-gpiochip.h>
 #include <linux/io.h>
 #include <linux/of_platform.h>
 #include <linux/module.h>
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index 266352b1a966..0f699af438b0 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -892,6 +892,8 @@ static int of_gpio_simple_xlate(struct gpio_chip *gc,
 	return gpiospec->args[0];
 }
 
+#if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP)
+#include <linux/gpio/legacy-of-mm-gpiochip.h>
 /**
  * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)
  * @np:		device node of the GPIO chip
@@ -964,6 +966,7 @@ void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)
 	kfree(gc->label);
 }
 EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
+#endif
 
 #ifdef CONFIG_PINCTRL
 static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
diff --git a/drivers/soc/fsl/qe/gpio.c b/drivers/soc/fsl/qe/gpio.c
index 1c41eb49d5a7..3ef24ba0245b 100644
--- a/drivers/soc/fsl/qe/gpio.c
+++ b/drivers/soc/fsl/qe/gpio.c
@@ -13,7 +13,7 @@
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>	/* for of_mm_gpio_chip */
+#include <linux/gpio/legacy-of-mm-gpiochip.h>
 #include <linux/gpio/consumer.h>
 #include <linux/gpio/driver.h>
 #include <linux/slab.h>