gpio/pinctrl Pullup/OpenDrain patch

2 files changed, 151 insertions, 1 deletions

diff --git a/recipes-kernel/linux/linux-at91-4.9/linux-4.9-at91_gpio_set_single_ended.patch b/recipes-kernel/linux/linux-at91-4.9/linux-4.9-at91_gpio_set_single_ended.patch
new file mode 100644
index 0000000..25da603
--- /dev/null
+++ b/recipes-kernel/linux/linux-at91-4.9/linux-4.9-at91_gpio_set_single_ended.patch
@@ -0,0 +1,148 @@
+diff -Naru linux-4.9.orig/drivers/gpio/gpiolib.c linux-4.9/drivers/gpio/gpiolib.c
+--- linux-4.9.orig/drivers/gpio/gpiolib.c	2018-12-11 10:11:06.000000000 -0600
++++ linux-4.9/drivers/gpio/gpiolib.c	2018-12-12 10:20:01.690638477 -0600
+@@ -478,6 +478,8 @@
+ 			set_bit(FLAG_OPEN_DRAIN, &desc->flags);
+ 		if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
+ 			set_bit(FLAG_OPEN_SOURCE, &desc->flags);
++		if (lflags & GPIOHANDLE_REQUEST_PULLUP)
++			set_bit(FLAG_PULLUP, &desc->flags);
+ 
+ 		/*
+ 		 * Lines have to be requested explicitly for input
+@@ -804,6 +806,8 @@
+ 		set_bit(FLAG_OPEN_DRAIN, &desc->flags);
+ 	if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
+ 		set_bit(FLAG_OPEN_SOURCE, &desc->flags);
++	if (lflags & GPIOHANDLE_REQUEST_PULLUP)
++		set_bit(FLAG_PULLUP, &desc->flags);
+ 
+ 	ret = gpiod_direction_input(desc);
+ 	if (ret)
+@@ -953,6 +957,8 @@
+ 			lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN;
+ 		if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
+ 			lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE;
++		if (test_bit(FLAG_PULLUP, &desc->flags))
++			lineinfo.flags |= GPIOLINE_FLAG_PULLUP;
+ 
+ 		if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
+ 			return -EFAULT;
+@@ -2090,6 +2096,7 @@
+ 		clear_bit(FLAG_REQUESTED, &desc->flags);
+ 		clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
+ 		clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
++                clear_bit(FLAG_PULLUP, &desc->flags);
+ 		clear_bit(FLAG_IS_HOGGED, &desc->flags);
+ 		ret = true;
+ 	}
+@@ -2256,6 +2263,17 @@
+ 			if (!ret)
+ 				goto set_output_value;
+ 		}
++		/* Emulate open source by not actively driving the line low */
++		if (!value)
++			return gpiod_direction_input(desc);
++	}
++	else if (test_bit(FLAG_PULLUP, &desc->flags)) {
++		if (gc->set_single_ended) {
++			ret = gc->set_single_ended(gc, gpio_chip_hwgpio(desc),
++						   LINE_MODE_PULLUP);
++			if (!ret)
++				goto set_output_value;
++		}
+ 		/* Emulate open source by not actively driving the line low */
+ 		if (!value)
+ 			return gpiod_direction_input(desc);
+diff -Naru linux-4.9.orig/drivers/gpio/gpiolib.h linux-4.9/drivers/gpio/gpiolib.h
+--- linux-4.9.orig/drivers/gpio/gpiolib.h	2018-12-11 12:10:06.937000782 -0600
++++ linux-4.9/drivers/gpio/gpiolib.h	2018-12-11 12:11:30.324998313 -0600
+@@ -189,6 +189,7 @@
+ #define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
+ #define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
+ #define FLAG_IS_HOGGED	11	/* GPIO is hogged */
++#define FLAG_PULLUP	12	/* GPIO is pulled up */
+ 
+ 	/* Connection label */
+ 	const char		*label;
+diff -Naru linux-4.9.orig/drivers/pinctrl/pinctrl-at91.c linux-4.9/drivers/pinctrl/pinctrl-at91.c
+--- linux-4.9.orig/drivers/pinctrl/pinctrl-at91.c	2018-12-11 10:11:15.000000000 -0600
++++ linux-4.9/drivers/pinctrl/pinctrl-at91.c	2018-12-12 10:25:46.154628279 -0600
+@@ -1671,6 +1671,33 @@
+ 	return -EINVAL;
+ }
+ 
++static int at91_gpio_set_single_ended(struct gpio_chip *chip, unsigned offset, enum single_ended_mode mode)
++{
++ 	struct at91_gpio_chip *at91_gpio = gpiochip_get_data(chip);
++	void __iomem *pio = at91_gpio->regbase;
++	unsigned mask = 1 << offset;
++ 
++	/* Other possibilities:
++	 *    PIO_IFSCDR, PIO_IFSCER (Input Filter Slow Clock disable/enable register)
++	 *    PIO_SCDR (Slow Clock Divider Debouncing register)
++	 */
++        switch(mode) {
++            case LINE_MODE_PULLUP:
++                    at91_mux_set_pullup(pio, mask, true);
++                    return 0;
++            case LINE_MODE_OPEN_DRAIN:
++                    /* Open Drain is Multi Drive */
++                    at91_mux_set_multidrive(pio, mask, true);
++                    return 0;
++            case LINE_MODE_PUSH_PULL:
++                    /* Not pull up or open drain */
++                    at91_mux_set_pullup(pio, mask, false);
++                    at91_mux_set_multidrive(pio, mask, false);
++                    return 0;
++            default: return -EINVAL;
++        }
++}
++
+ /* This structure is replicated for each GPIO block allocated at probe time */
+ static const struct gpio_chip at91_gpio_template = {
+ 	.request		= gpiochip_generic_request,
+@@ -1681,6 +1708,7 @@
+ 	.direction_output	= at91_gpio_direction_output,
+ 	.set			= at91_gpio_set,
+ 	.set_multiple		= at91_gpio_set_multiple,
++        .set_single_ended       = at91_gpio_set_single_ended,
+ 	.dbg_show		= at91_gpio_dbg_show,
+ 	.can_sleep		= false,
+ 	.ngpio			= MAX_NB_GPIO_PER_BANK,
+diff -Naru linux-4.9.orig/include/linux/gpio/driver.h linux-4.9/include/linux/gpio/driver.h
+--- linux-4.9.orig/include/linux/gpio/driver.h	2018-12-11 10:11:20.000000000 -0600
++++ linux-4.9/include/linux/gpio/driver.h	2018-12-11 17:47:56.188400715 -0600
+@@ -23,11 +23,13 @@
+  * @LINE_MODE_PUSH_PULL: normal mode for a GPIO line, drive actively high/low
+  * @LINE_MODE_OPEN_DRAIN: set line to be open drain
+  * @LINE_MODE_OPEN_SOURCE: set line to be open source
++ * @LINE_MODE_PULLUP: set line to be pullup
+  */
+ enum single_ended_mode {
+ 	LINE_MODE_PUSH_PULL,
+ 	LINE_MODE_OPEN_DRAIN,
+ 	LINE_MODE_OPEN_SOURCE,
++        LINE_MODE_PULLUP,
+ };
+ 
+ /**
+diff -Naru linux-4.9.orig/include/uapi/linux/gpio.h linux-4.9/include/uapi/linux/gpio.h
+--- linux-4.9.orig/include/uapi/linux/gpio.h	2018-12-11 10:11:21.000000000 -0600
++++ linux-4.9/include/uapi/linux/gpio.h	2018-12-11 12:21:03.884981333 -0600
+@@ -32,6 +32,7 @@
+ #define GPIOLINE_FLAG_ACTIVE_LOW	(1UL << 2)
+ #define GPIOLINE_FLAG_OPEN_DRAIN	(1UL << 3)
+ #define GPIOLINE_FLAG_OPEN_SOURCE	(1UL << 4)
++#define GPIOLINE_FLAG_PULLUP    	(1UL << 5)
+ 
+ /**
+  * struct gpioline_info - Information about a certain GPIO line
+@@ -61,6 +62,7 @@
+ #define GPIOHANDLE_REQUEST_ACTIVE_LOW	(1UL << 2)
+ #define GPIOHANDLE_REQUEST_OPEN_DRAIN	(1UL << 3)
+ #define GPIOHANDLE_REQUEST_OPEN_SOURCE	(1UL << 4)
++#define GPIOHANDLE_REQUEST_PULLUP	(1UL << 5)
+ 
+ /**
+  * struct gpiohandle_request - Information about a GPIO handle request
diff --git a/recipes-kernel/linux/linux-at91_4.9.bb b/recipes-kernel/linux/linux-at91_4.9.bb
index fe728ba..243bdd0 100644
--- a/recipes-kernel/linux/linux-at91_4.9.bb
+++ b/recipes-kernel/linux/linux-at91_4.9.bb
@@ -25,13 +25,15 @@ SRC_URI += "file://defconfig"
 
 COMMON_PATCHES = "file://linux-4.9-pps-gpio.patch"
 
+#            file://at91pinctrl_reprobe.patch
+
 SRC_URI_append_mtcdt = "\
             ${COMMON_PATCHES} \
             file://defconfig \
             file://linux-4.9-mtcdt-device-tree.patch \
             file://linux-4.9-add-num_accessory_ports-config-option.patch \
             file://950-0090-OF-DT-Overlay-configfs-interface.patch \
-            file://at91pinctrl_reprobe.patch \
+            file://linux-4.9-at91_gpio_set_single_ended.patch \
             "
 
 DTB_APPEND_mtcdt = "mtcdt"