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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
|
