Merge tag 'gpio-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.19 kernel cycle.

  I don't know if anything in particular stands out. Maybe the Aspeed
  coprocessor thing from Benji: Aspeed is doing baseboard management
  chips (BMC's) for servers etc.

  These Aspeed's are ARM processors that exist inside (I guess) Intel
  servers, and they are moving forward to using mainline Linux in those.
  This is one of the pieces of the puzzle to achive that. They are doing
  OpenBMC, it's pretty cool: https://lwn.net/Articles/683320/

  Summary:

  Core changes:

   - Add a new API for explicitly naming GPIO consumers, when needed.

   - Don't let userspace set values on input lines. While we do not
     think anyone would do this crazy thing we better plug the hole
     before someone uses it and think it's a nifty feature.

   - Avoid calling chip->request() for unused GPIOs.

  New drivers/subdrivers:

   - The Mediatek MT7621 is supported which is a big win for OpenWRT and
     similar router distributions using this chip, as it seems every
     major router manufacturer on the planet has made products using
     this chip: https://wikidevi.com/wiki/MediaTek_MT7621

   - The Tegra 194 is now supported.

   - The IT87 driver now supports IT8786E and IT8718F super-IO chips.

   - Add support for Rockchip RK3328 in the syscon GPIO driver.

  Driver changes:

   - Handle the get/set_multiple() properly on MMIO chips with inverted
     direction registers. We didn't have this problem until a new chip
     appear that has get/set registers AND inverted direction bits, OK
     now we handle it.

   - A patch series making more error codes percolate upward properly
     for different errors on gpiochip_lock_as_irq().

   - Get/set multiple for the OMAP driver, accelerating these multiple
     line operations if possible.

   - A coprocessor interface for the Aspeed driver. Sometimes a few GPIO
     lines need to be grabbed by a co-processor for doing automated
     tasks, sometimes they are available as GPIO lines. By adding an
     explicit API in this driver we make it possible for the two line
     consumers to coexist. (This work was made available on the
     ib-aspeed branch, which may be appearing in other pull requests.)

   - Implemented .get_direction() and open drain in the SCH311x driver.

   - Continuing cleanup of included headers in GPIO drivers"

* tag 'gpio-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (80 commits)
  gpio: it87: Add support for IT8613
  gpio: it87: add support for IT8718F Super I/O.
  gpiolib: Avoid calling chip->request() for unused gpios
  gpio: tegra: Include the right header
  gpio: mmio: Fix up inverted direction registers
  gpio: xilinx: Use the right include
  gpio: timberdale: Include the right header
  gpio: tb10x: Use the right include
  gpiolib: Fix of_node inconsistency
  gpio: vr41xx: Bail out on gpiochip_lock_as_irq() error
  gpio: uniphier: Bail out on gpiochip_lock_as_irq() error
  gpio: xgene-sb: Don't shadow error code of gpiochip_lock_as_irq()
  gpio: em: Don't shadow error code of gpiochip_lock_as_irq()
  gpio: dwapb: Don't shadow error code of gpiochip_lock_as_irq()
  gpio: bcm-kona: Don't shadow error code of gpiochip_lock_as_irq()
  gpiolib: Don't shadow error code of gpiochip_lock_as_irq()
  gpio: syscon: rockchip: add GRF GPIO support for rk3328
  gpio: omap: Add get/set_multiple() callbacks
  gpio: pxa: remove set but not used variable 'gpio_offset'
  gpio-it87: add support for IT8786E Super I/O
  ...

1 files changed, 63 insertions, 45 deletions

diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c
index 7b14d6280e44..935292a30c99 100644
--- a/drivers/gpio/gpio-mmio.c
+++ b/drivers/gpio/gpio-mmio.c
@@ -136,8 +136,20 @@ static unsigned long bgpio_line2mask(struct gpio_chip *gc, unsigned int line)
 static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio)
 {
         unsigned long pinmask = bgpio_line2mask(gc, gpio);
+        bool dir = !!(gc->bgpio_dir & pinmask);
 
-        if (gc->bgpio_dir & pinmask)
+        /*
+         * If the direction is OUT we read the value from the SET
+         * register, and if the direction is IN we read the value
+         * from the DAT register.
+         *
+         * If the direction bits are inverted, naturally this gets
+         * inverted too.
+         */
+        if (gc->bgpio_dir_inverted)
+                dir = !dir;
+
+        if (dir)
                 return !!(gc->read_reg(gc->reg_set) & pinmask);
         else
                 return !!(gc->read_reg(gc->reg_dat) & pinmask);
@@ -157,8 +169,13 @@ static int bgpio_get_set_multiple(struct gpio_chip *gc, unsigned long *mask,
         *bits &= ~*mask;
 
         /* Exploit the fact that we know which directions are set */
-        set_mask = *mask & gc->bgpio_dir;
-        get_mask = *mask & ~gc->bgpio_dir;
+        if (gc->bgpio_dir_inverted) {
+                set_mask = *mask & ~gc->bgpio_dir;
+                get_mask = *mask & gc->bgpio_dir;
+        } else {
+                set_mask = *mask & gc->bgpio_dir;
+                get_mask = *mask & ~gc->bgpio_dir;
+        }
 
         if (set_mask)
                 *bits |= gc->read_reg(gc->reg_set) & set_mask;
@@ -359,7 +376,10 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 
         spin_lock_irqsave(&gc->bgpio_lock, flags);
 
-        gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
+        if (gc->bgpio_dir_inverted)
+                gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
+        else
+                gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
         gc->write_reg(gc->reg_dir, gc->bgpio_dir);
 
         spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -370,7 +390,10 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 static int bgpio_get_dir(struct gpio_chip *gc, unsigned int gpio)
 {
         /* Return 0 if output, 1 of input */
-        return !(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));
+        if (gc->bgpio_dir_inverted)
+                return !!(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));
+        else
+                return !(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));
 }
 
 static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
@@ -381,37 +404,10 @@ static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 
         spin_lock_irqsave(&gc->bgpio_lock, flags);
 
-        gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
-        gc->write_reg(gc->reg_dir, gc->bgpio_dir);
-
-        spin_unlock_irqrestore(&gc->bgpio_lock, flags);
-
-        return 0;
-}
-
-static int bgpio_dir_in_inv(struct gpio_chip *gc, unsigned int gpio)
-{
-        unsigned long flags;
-
-        spin_lock_irqsave(&gc->bgpio_lock, flags);
-
-        gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
-        gc->write_reg(gc->reg_dir, gc->bgpio_dir);
-
-        spin_unlock_irqrestore(&gc->bgpio_lock, flags);
-
-        return 0;
-}
-
-static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val)
-{
-        unsigned long flags;
-
-        gc->set(gc, gpio, val);
-
-        spin_lock_irqsave(&gc->bgpio_lock, flags);
-
-        gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
+        if (gc->bgpio_dir_inverted)
+                gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
+        else
+                gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
         gc->write_reg(gc->reg_dir, gc->bgpio_dir);
 
         spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -419,12 +415,6 @@ static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val)
         return 0;
 }
 
-static int bgpio_get_dir_inv(struct gpio_chip *gc, unsigned int gpio)
-{
-        /* Return 0 if output, 1 if input */
-        return !!(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));
-}
-
 static int bgpio_setup_accessors(struct device *dev,
                                  struct gpio_chip *gc,
                                  bool byte_be)
@@ -560,9 +550,10 @@ static int bgpio_setup_direction(struct gpio_chip *gc,
                 gc->get_direction = bgpio_get_dir;
         } else if (dirin) {
                 gc->reg_dir = dirin;
-                gc->direction_output = bgpio_dir_out_inv;
-                gc->direction_input = bgpio_dir_in_inv;
-                gc->get_direction = bgpio_get_dir_inv;
+                gc->direction_output = bgpio_dir_out;
+                gc->direction_input = bgpio_dir_in;
+                gc->get_direction = bgpio_get_dir;
+                gc->bgpio_dir_inverted = true;
         } else {
                 if (flags & BGPIOF_NO_OUTPUT)
                         gc->direction_output = bgpio_dir_out_err;
@@ -582,6 +573,33 @@ static int bgpio_request(struct gpio_chip *chip, unsigned gpio_pin)
         return -EINVAL;
 }
 
+/**
+ * bgpio_init() - Initialize generic GPIO accessor functions
+ * @gc: the GPIO chip to set up
+ * @dev: the parent device of the new GPIO chip (compulsory)
+ * @sz: the size (width) of the MMIO registers in bytes, typically 1, 2 or 4
+ * @dat: MMIO address for the register to READ the value of the GPIO lines, it
+ *      is expected that a 1 in the corresponding bit in this register means the
+ *      line is asserted
+ * @set: MMIO address for the register to SET the value of the GPIO lines, it is
+ *      expected that we write the line with 1 in this register to drive the GPIO line
+ *      high.
+ * @clr: MMIO address for the register to CLEAR the value of the GPIO lines, it is
+ *      expected that we write the line with 1 in this register to drive the GPIO line
+ *      low. It is allowed to leave this address as NULL, in that case the SET register
+ *      will be assumed to also clear the GPIO lines, by actively writing the line
+ *      with 0.
+ * @dirout: MMIO address for the register to set the line as OUTPUT. It is assumed
+ *      that setting a line to 1 in this register will turn that line into an
+ *      output line. Conversely, setting the line to 0 will turn that line into
+ *      an input. Either this or @dirin can be defined, but never both.
+ * @dirin: MMIO address for the register to set this line as INPUT. It is assumed
+ *      that setting a line to 1 in this register will turn that line into an
+ *      input line. Conversely, setting the line to 0 will turn that line into
+ *      an output. Either this or @dirout can be defined, but never both.
+ * @flags: Different flags that will affect the behaviour of the device, such as
+ *      endianness etc.
+ */
 int bgpio_init(struct gpio_chip *gc, struct device *dev,
                unsigned long sz, void __iomem *dat, void __iomem *set,
                void __iomem *clr, void __iomem *dirout, void __iomem *dirin,