Merge tag 'gpio-v4.20-1' 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 v4.20 series:

  Core changes:

   - A patch series from Hans Verkuil to make it possible to
     enable/disable IRQs on a GPIO line at runtime and drive GPIO lines
     as output without having to put/get them from scratch.

     The irqchip callbacks have been improved so that they can use only
     the fastpatch callbacks to enable/disable irqs like any normal
     irqchip, especially the gpiod_lock_as_irq() has been improved to be
     callable in fastpath context.

     A bunch of rework had to be done to achieve this but it is a big
     win since I never liked to restrict this to slowpath. The only call
     requireing slowpath was try_module_get() and this is kept at the
     .request_resources() slowpath callback. In the GPIO CEC driver this
     is a big win sine a single line is used for both outgoing and
     incoming traffic, and this needs to use IRQs for incoming traffic
     while actively driving the line for outgoing traffic.

   - Janusz Krzysztofik improved the GPIO array API to pass a "cookie"
     (struct gpio_array) and a bitmap for setting or getting multiple
     GPIO lines at once.

     This improvement orginated in a specific need to speed up an OMAP1
     driver and has led to a much better API and real performance gains
     when the state of the array can be used to bypass a lot of checks
     and code when we want things to go really fast.

     The previous code would minimize the number of calls down to the
     driver callbacks assuming the CPU speed was orders of magnitude
     faster than the I/O latency, but this assumption was wrong on
     several platforms: what we needed to do was to profile and improve
     the speed on the hot path of the array functions and this change is
     now completed.

   - Clean out the painful and hard to grasp BNF experiments from the
     device tree bindings. Future approaches are looking into using JSON
     schema for this purpose. (Rob Herring is floating a patch series.)

  New drivers:

   - The RCAR driver now supports r8a774a1 (RZ/G2M).

   - Synopsys GPIO via CREGs driver.

  Major improvements:

   - Modernization of the EP93xx driver to use irqdomain and other
     contemporary concepts.

   - The ingenic driver has been merged into the Ingenic pin control
     driver and removed from the GPIO subsystem.

   - Debounce support in the ftgpio010 driver"

* tag 'gpio-v4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (116 commits)
  gpio: Clarify kerneldoc on gpiochip_set_chained_irqchip()
  gpio: Remove unused 'irqchip' argument to gpiochip_set_cascaded_irqchip()
  gpio: Drop parent irq assignment during cascade setup
  mmc: pwrseq_simple: Fix incorrect handling of GPIO bitmap
  gpio: fix SNPS_CREG kconfig dependency warning
  gpiolib: Initialize gdev field before is used
  gpio: fix kernel-doc after devres.c file rename
  gpio: fix doc string for devm_gpiochip_add_data() to not talk about irq_chip
  gpio: syscon: Fix possible NULL ptr usage
  gpiolib: Show correct direction from the beginning
  pinctrl: msm: Use init_valid_mask exported function
  gpiolib: Add init_valid_mask exported function
  GPIO: add single-register GPIO via CREG driver
  dt-bindings: Document the Synopsys GPIO via CREG bindings
  gpio: mockup: use device properties instead of platform_data
  gpio: Slightly more helpful debugfs
  gpio: omap: Remove set but not used variable 'dev'
  gpio: omap: drop omap_gpio_list
  Accept partial 'gpio-line-names' property.
  gpio: omap: get rid of the conditional PM runtime calls
  ...

1 files changed, 191 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-creg-snps.c b/drivers/gpio/gpio-creg-snps.c
new file mode 100644
index 000000000000..8cbc94d0d424
--- /dev/null
+++ b/drivers/gpio/gpio-creg-snps.c
@@ -0,0 +1,191 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Synopsys CREG (Control REGisters) GPIO driver
+//
+// Copyright (C) 2018 Synopsys
+// Author: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
+
+#include <linux/gpio/driver.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+
+#define MAX_GPIO	32
+
+struct creg_layout {
+	u8 ngpio;
+	u8 shift[MAX_GPIO];
+	u8 on[MAX_GPIO];
+	u8 off[MAX_GPIO];
+	u8 bit_per_gpio[MAX_GPIO];
+};
+
+struct creg_gpio {
+	struct gpio_chip gc;
+	void __iomem *regs;
+	spinlock_t lock;
+	const struct creg_layout *layout;
+};
+
+static void creg_gpio_set(struct gpio_chip *gc, unsigned int offset, int val)
+{
+	struct creg_gpio *hcg = gpiochip_get_data(gc);
+	const struct creg_layout *layout = hcg->layout;
+	u32 reg, reg_shift, value;
+	unsigned long flags;
+	int i;
+
+	value = val ? hcg->layout->on[offset] : hcg->layout->off[offset];
+
+	reg_shift = layout->shift[offset];
+	for (i = 0; i < offset; i++)
+		reg_shift += layout->bit_per_gpio[i] + layout->shift[i];
+
+	spin_lock_irqsave(&hcg->lock, flags);
+	reg = readl(hcg->regs);
+	reg &= ~(GENMASK(layout->bit_per_gpio[i] - 1, 0) << reg_shift);
+	reg |=  (value << reg_shift);
+	writel(reg, hcg->regs);
+	spin_unlock_irqrestore(&hcg->lock, flags);
+}
+
+static int creg_gpio_dir_out(struct gpio_chip *gc, unsigned int offset, int val)
+{
+	creg_gpio_set(gc, offset, val);
+
+	return 0;
+}
+
+static int creg_gpio_validate_pg(struct device *dev, struct creg_gpio *hcg,
+				 int i)
+{
+	const struct creg_layout *layout = hcg->layout;
+
+	if (layout->bit_per_gpio[i] < 1 || layout->bit_per_gpio[i] > 8)
+		return -EINVAL;
+
+	/* Check that on valiue fits it's placeholder */
+	if (GENMASK(31, layout->bit_per_gpio[i]) & layout->on[i])
+		return -EINVAL;
+
+	/* Check that off valiue fits it's placeholder */
+	if (GENMASK(31, layout->bit_per_gpio[i]) & layout->off[i])
+		return -EINVAL;
+
+	if (layout->on[i] == layout->off[i])
+		return -EINVAL;
+
+	return 0;
+}
+
+static int creg_gpio_validate(struct device *dev, struct creg_gpio *hcg,
+			      u32 ngpios)
+{
+	u32 reg_len = 0;
+	int i;
+
+	if (hcg->layout->ngpio < 1 || hcg->layout->ngpio > MAX_GPIO)
+		return -EINVAL;
+
+	if (ngpios < 1 || ngpios > hcg->layout->ngpio) {
+		dev_err(dev, "ngpios must be in [1:%u]\n", hcg->layout->ngpio);
+		return -EINVAL;
+	}
+
+	for (i = 0; i < hcg->layout->ngpio; i++) {
+		if (creg_gpio_validate_pg(dev, hcg, i))
+			return -EINVAL;
+
+		reg_len += hcg->layout->shift[i] + hcg->layout->bit_per_gpio[i];
+	}
+
+	/* Check that we fit in 32 bit register */
+	if (reg_len > 32)
+		return -EINVAL;
+
+	return 0;
+}
+
+static const struct creg_layout hsdk_cs_ctl = {
+	.ngpio		= 10,
+	.shift		= { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
+	.off		= { 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 },
+	.on		= { 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 },
+	.bit_per_gpio	= { 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 }
+};
+
+static const struct creg_layout axs10x_flsh_cs_ctl = {
+	.ngpio		= 1,
+	.shift		= { 0 },
+	.off		= { 1 },
+	.on		= { 3 },
+	.bit_per_gpio	= { 2 }
+};
+
+static const struct of_device_id creg_gpio_ids[] = {
+	{
+		.compatible = "snps,creg-gpio-axs10x",
+		.data = &axs10x_flsh_cs_ctl
+	}, {
+		.compatible = "snps,creg-gpio-hsdk",
+		.data = &hsdk_cs_ctl
+	}, { /* sentinel */ }
+};
+
+static int creg_gpio_probe(struct platform_device *pdev)
+{
+	const struct of_device_id *match;
+	struct device *dev = &pdev->dev;
+	struct creg_gpio *hcg;
+	struct resource *mem;
+	u32 ngpios;
+	int ret;
+
+	hcg = devm_kzalloc(dev, sizeof(struct creg_gpio), GFP_KERNEL);
+	if (!hcg)
+		return -ENOMEM;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	hcg->regs = devm_ioremap_resource(dev, mem);
+	if (IS_ERR(hcg->regs))
+		return PTR_ERR(hcg->regs);
+
+	match = of_match_node(creg_gpio_ids, pdev->dev.of_node);
+	hcg->layout = match->data;
+	if (!hcg->layout)
+		return -EINVAL;
+
+	ret = of_property_read_u32(dev->of_node, "ngpios", &ngpios);
+	if (ret)
+		return ret;
+
+	ret = creg_gpio_validate(dev, hcg, ngpios);
+	if (ret)
+		return ret;
+
+	spin_lock_init(&hcg->lock);
+
+	hcg->gc.label = dev_name(dev);
+	hcg->gc.base = -1;
+	hcg->gc.ngpio = ngpios;
+	hcg->gc.set = creg_gpio_set;
+	hcg->gc.direction_output = creg_gpio_dir_out;
+	hcg->gc.of_node = dev->of_node;
+
+	ret = devm_gpiochip_add_data(dev, &hcg->gc, hcg);
+	if (ret)
+		return ret;
+
+	dev_info(dev, "GPIO controller with %d gpios probed\n", ngpios);
+
+	return 0;
+}
+
+static struct platform_driver creg_gpio_snps_driver = {
+	.driver = {
+		.name = "snps-creg-gpio",
+		.of_match_table = creg_gpio_ids,
+	},
+	.probe  = creg_gpio_probe,
+};
+builtin_platform_driver(creg_gpio_snps_driver);