Merge tag 'gpio-v4.15-1' of ssh://gitolite.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 v4.15 kernel cycle:

  Core:

   - Fix the semantics of raw GPIO to actually be raw. No inversion
     semantics as before, but also no open draining, and allow the raw
     operations to affect lines used for interrupts as the caller
     supposedly knows what they are doing if they are getting the big
     hammer.

   - Rewrote the __inner_function() notation calls to names that make
     more sense. I just find this kind of code disturbing.

   - Drop the .irq_base() field from the gpiochip since now all IRQs are
     mapped dynamically. This is nice.

   - Support for .get_multiple() in the core driver API. This allows us
     to read several GPIO lines with a single register read. This has
     high value for some usecases: it can be used to create
     oscilloscopes and signal analyzers and other things that rely on
     reading several lines at exactly the same instant. Also a generally
     nice optimization. This uses the new assign_bit() macro from the
     bitops lib that was ACKed by Andrew Morton and is implemented for
     two drivers, one of them being the generic MMIO driver so everyone
     using that will be able to benefit from this.

   - Do not allow requests of Open Drain and Open Source setting of a
     GPIO line simultaneously. If the hardware actually supports
     enabling both at the same time the electrical result would be
     disastrous.

   - A new interrupt chip core helper. This will be helpful to deal with
     "banked" GPIOs, which means GPIO controllers with several logical
     blocks of GPIO inside them. This is several gpiochips per device in
     the device model, in contrast to the case when there is a 1-to-1
     relationship between a device and a gpiochip.

  New drivers:

   - Maxim MAX3191x industrial serializer, a very interesting piece of
     professional I/O hardware.

   - Uniphier GPIO driver. This is the GPIO block from the recent
     Socionext (ex Fujitsu and Panasonic) platform.

   - Tegra 186 driver. This is based on the new banked GPIO
     infrastructure.

  Other improvements:

   - Some documentation improvements.

   - Wakeup support for the DesignWare DWAPB GPIO controller.

   - Reset line support on the DesignWare DWAPB GPIO controller.

   - Several non-critical bug fixes and improvements for the Broadcom
     BRCMSTB driver.

   - Misc non-critical bug fixes like exotic errorpaths, removal of dead
     code etc.

   - Explicit comments on fall-through switch() statements"

* tag 'gpio-v4.15-1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (65 commits)
  gpio: tegra186: Remove tegra186_gpio_lock_class
  gpio: rcar: Add r8a77995 (R-Car D3) support
  pinctrl: bcm2835: Fix some merge fallout
  gpio: Fix undefined lock_dep_class
  gpio: Automatically add lockdep keys
  gpio: Introduce struct gpio_irq_chip.first
  gpio: Disambiguate struct gpio_irq_chip.nested
  gpio: Add Tegra186 support
  gpio: Export gpiochip_irq_{map,unmap}()
  gpio: Implement tighter IRQ chip integration
  gpio: Move lock_key into struct gpio_irq_chip
  gpio: Move irq_valid_mask into struct gpio_irq_chip
  gpio: Move irq_nested into struct gpio_irq_chip
  gpio: Move irq_chained_parent to struct gpio_irq_chip
  gpio: Move irq_default_type to struct gpio_irq_chip
  gpio: Move irq_handler to struct gpio_irq_chip
  gpio: Move irqdomain into struct gpio_irq_chip
  gpio: Move irqchip into struct gpio_irq_chip
  gpio: Introduce struct gpio_irq_chip
  pinctrl: armada-37xx: remove unused variable
  ...

1 files changed, 102 insertions, 28 deletions

diff --git a/drivers/gpio/gpio-mmio.c b/drivers/gpio/gpio-mmio.c
index f7da40e46c55..f9042bcc27a4 100644
--- a/drivers/gpio/gpio-mmio.c
+++ b/drivers/gpio/gpio-mmio.c
@@ -126,20 +126,16 @@ static unsigned long bgpio_read32be(void __iomem *reg)
         return ioread32be(reg);
 }
 
-static unsigned long bgpio_pin2mask(struct gpio_chip *gc, unsigned int pin)
+static unsigned long bgpio_line2mask(struct gpio_chip *gc, unsigned int line)
 {
-        return BIT(pin);
-}
-
-static unsigned long bgpio_pin2mask_be(struct gpio_chip *gc,
-                                       unsigned int pin)
-{
-        return BIT(gc->bgpio_bits - 1 - pin);
+        if (gc->be_bits)
+                return BIT(gc->bgpio_bits - 1 - line);
+        return BIT(line);
 }
 
 static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio)
 {
-        unsigned long pinmask = gc->pin2mask(gc, gpio);
+        unsigned long pinmask = bgpio_line2mask(gc, gpio);
 
         if (gc->bgpio_dir & pinmask)
                 return !!(gc->read_reg(gc->reg_set) & pinmask);
@@ -147,9 +143,76 @@ static int bgpio_get_set(struct gpio_chip *gc, unsigned int gpio)
                 return !!(gc->read_reg(gc->reg_dat) & pinmask);
 }
 
+/*
+ * This assumes that the bits in the GPIO register are in native endianness.
+ * We only assign the function pointer if we have that.
+ */
+static int bgpio_get_set_multiple(struct gpio_chip *gc, unsigned long *mask,
+                                  unsigned long *bits)
+{
+        unsigned long get_mask = 0;
+        unsigned long set_mask = 0;
+        int bit = 0;
+
+        while ((bit = find_next_bit(mask, gc->ngpio, bit)) != gc->ngpio) {
+                if (gc->bgpio_dir & BIT(bit))
+                        set_mask |= BIT(bit);
+                else
+                        get_mask |= BIT(bit);
+        }
+
+        if (set_mask)
+                *bits |= gc->read_reg(gc->reg_set) & set_mask;
+        if (get_mask)
+                *bits |= gc->read_reg(gc->reg_dat) & get_mask;
+
+        return 0;
+}
+
 static int bgpio_get(struct gpio_chip *gc, unsigned int gpio)
 {
-        return !!(gc->read_reg(gc->reg_dat) & gc->pin2mask(gc, gpio));
+        return !!(gc->read_reg(gc->reg_dat) & bgpio_line2mask(gc, gpio));
+}
+
+/*
+ * This only works if the bits in the GPIO register are in native endianness.
+ * It is dirt simple and fast in this case. (Also the most common case.)
+ */
+static int bgpio_get_multiple(struct gpio_chip *gc, unsigned long *mask,
+                              unsigned long *bits)
+{
+
+        *bits = gc->read_reg(gc->reg_dat) & *mask;
+        return 0;
+}
+
+/*
+ * With big endian mirrored bit order it becomes more tedious.
+ */
+static int bgpio_get_multiple_be(struct gpio_chip *gc, unsigned long *mask,
+                                 unsigned long *bits)
+{
+        unsigned long readmask = 0;
+        unsigned long val;
+        int bit;
+
+        /* Create a mirrored mask */
+        bit = 0;
+        while ((bit = find_next_bit(mask, gc->ngpio, bit)) != gc->ngpio)
+                readmask |= bgpio_line2mask(gc, bit);
+
+        /* Read the register */
+        val = gc->read_reg(gc->reg_dat) & readmask;
+
+        /*
+         * Mirror the result into the "bits" result, this will give line 0
+         * in bit 0 ... line 31 in bit 31 for a 32bit register.
+         */
+        bit = 0;
+        while ((bit = find_next_bit(&val, gc->ngpio, bit)) != gc->ngpio)
+                *bits |= bgpio_line2mask(gc, bit);
+
+        return 0;
 }
 
 static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val)
@@ -158,7 +221,7 @@ static void bgpio_set_none(struct gpio_chip *gc, unsigned int gpio, int val)
 
 static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
 {
-        unsigned long mask = gc->pin2mask(gc, gpio);
+        unsigned long mask = bgpio_line2mask(gc, gpio);
         unsigned long flags;
 
         spin_lock_irqsave(&gc->bgpio_lock, flags);
@@ -176,7 +239,7 @@ static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
 static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio,
                                  int val)
 {
-        unsigned long mask = gc->pin2mask(gc, gpio);
+        unsigned long mask = bgpio_line2mask(gc, gpio);
 
         if (val)
                 gc->write_reg(gc->reg_set, mask);
@@ -186,7 +249,7 @@ static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio,
 
 static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val)
 {
-        unsigned long mask = gc->pin2mask(gc, gpio);
+        unsigned long mask = bgpio_line2mask(gc, gpio);
         unsigned long flags;
 
         spin_lock_irqsave(&gc->bgpio_lock, flags);
@@ -216,9 +279,9 @@ static void bgpio_multiple_get_masks(struct gpio_chip *gc,
                         break;
                 if (__test_and_clear_bit(i, mask)) {
                         if (test_bit(i, bits))
-                                *set_mask |= gc->pin2mask(gc, i);
+                                *set_mask |= bgpio_line2mask(gc, i);
                         else
-                                *clear_mask |= gc->pin2mask(gc, i);
+                                *clear_mask |= bgpio_line2mask(gc, i);
                 }
         }
 }
@@ -294,7 +357,7 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 
         spin_lock_irqsave(&gc->bgpio_lock, flags);
 
-        gc->bgpio_dir &= ~gc->pin2mask(gc, gpio);
+        gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
         gc->write_reg(gc->reg_dir, gc->bgpio_dir);
 
         spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -305,7 +368,7 @@ 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) & gc->pin2mask(gc, gpio));
+        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)
@@ -316,7 +379,7 @@ static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 
         spin_lock_irqsave(&gc->bgpio_lock, flags);
 
-        gc->bgpio_dir |= gc->pin2mask(gc, gpio);
+        gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
         gc->write_reg(gc->reg_dir, gc->bgpio_dir);
 
         spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -330,7 +393,7 @@ static int bgpio_dir_in_inv(struct gpio_chip *gc, unsigned int gpio)
 
         spin_lock_irqsave(&gc->bgpio_lock, flags);
 
-        gc->bgpio_dir |= gc->pin2mask(gc, gpio);
+        gc->bgpio_dir |= bgpio_line2mask(gc, gpio);
         gc->write_reg(gc->reg_dir, gc->bgpio_dir);
 
         spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -346,7 +409,7 @@ static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val)
 
         spin_lock_irqsave(&gc->bgpio_lock, flags);
 
-        gc->bgpio_dir &= ~gc->pin2mask(gc, gpio);
+        gc->bgpio_dir &= ~bgpio_line2mask(gc, gpio);
         gc->write_reg(gc->reg_dir, gc->bgpio_dir);
 
         spin_unlock_irqrestore(&gc->bgpio_lock, flags);
@@ -357,12 +420,11 @@ static int bgpio_dir_out_inv(struct gpio_chip *gc, unsigned int gpio, int val)
 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) & gc->pin2mask(gc, gpio));
+        return !!(gc->read_reg(gc->reg_dir) & bgpio_line2mask(gc, gpio));
 }
 
 static int bgpio_setup_accessors(struct device *dev,
                                  struct gpio_chip *gc,
-                                 bool bit_be,
                                  bool byte_be)
 {
 
@@ -406,8 +468,6 @@ static int bgpio_setup_accessors(struct device *dev,
                 return -EINVAL;
         }
 
-        gc->pin2mask = bit_be ? bgpio_pin2mask_be : bgpio_pin2mask;
-
         return 0;
 }
 
@@ -462,10 +522,24 @@ static int bgpio_setup_io(struct gpio_chip *gc,
         }
 
         if (!(flags & BGPIOF_UNREADABLE_REG_SET) &&
-            (flags & BGPIOF_READ_OUTPUT_REG_SET))
+            (flags & BGPIOF_READ_OUTPUT_REG_SET)) {
                 gc->get = bgpio_get_set;
-        else
+                if (!gc->be_bits)
+                        gc->get_multiple = bgpio_get_set_multiple;
+                /*
+                 * We deliberately avoid assigning the ->get_multiple() call
+                 * for big endian mirrored registers which are ALSO reflecting
+                 * their value in the set register when used as output. It is
+                 * simply too much complexity, let the GPIO core fall back to
+                 * reading each line individually in that fringe case.
+                 */
+        } else {
                 gc->get = bgpio_get;
+                if (gc->be_bits)
+                        gc->get_multiple = bgpio_get_multiple_be;
+                else
+                        gc->get_multiple = bgpio_get_multiple;
+        }
 
         return 0;
 }
@@ -526,13 +600,13 @@ int bgpio_init(struct gpio_chip *gc, struct device *dev,
         gc->base = -1;
         gc->ngpio = gc->bgpio_bits;
         gc->request = bgpio_request;
+        gc->be_bits = !!(flags & BGPIOF_BIG_ENDIAN);
 
         ret = bgpio_setup_io(gc, dat, set, clr, flags);
         if (ret)
                 return ret;
 
-        ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN,
-                                    flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER);
+        ret = bgpio_setup_accessors(dev, gc, flags & BGPIOF_BIG_ENDIAN_BYTE_ORDER);
         if (ret)
                 return ret;