diff mbox series

[v3,2/2] usb: Add driver to allow any GPIO to be used for 7211 USB signals

Message ID 20201012200007.8862-3-alcooperx@gmail.com
State Superseded
Headers show
Series usb: Add driver for USB signal re-mapper | expand

Commit Message

Alan Cooper Oct. 12, 2020, 8 p.m. UTC
The Broadcom 7211 has new functionality that allows some USB low
speed side band signals, that go from the XHCI host controller to
pins on the chip, to be remapped to use any GPIO pin instead of the
limited set selectable by hardware. This can be done without changing
the standard driver for the host controller. There is currently
support for three USB signals, PWRON, VBUS_PRESENT and PWRFLT. This
driver will allow the remapping of any of these three signals based
on settings in the Device Tree node for the driver. The driver was
written so that it could handle additional signals added in the
future by just adding the correct properties to the DT node.

Below is an example of a DT node that would remap all three
signals:

usb_pinmap: usb-pinmap@22000d0 {
	compatible = "brcm,usb-pinmap";
	reg = <0x22000d0 0x4>;
	in-gpios = <&gpio 18 0>, <&gpio 19 0>;
	brcm,in-functions = "VBUS", "PWRFLT";
	brcm,in-masks = <0x8000 0x40000 0x10000 0x80000>;
	out-gpios = <&gpio 20 0>;
	brcm,out-functions = "PWRON";
	brcm,out-masks = <0x20000 0x800000 0x400000 0x200000>;
	interrupts = <0x0 0xb2 0x4>;
};

Signed-off-by: Al Cooper <alcooperx@gmail.com>
---
 MAINTAINERS                           |   8 +
 drivers/usb/misc/Kconfig              |   9 +
 drivers/usb/misc/Makefile             |   1 +
 drivers/usb/misc/brcmstb-usb-pinmap.c | 351 ++++++++++++++++++++++++++
 4 files changed, 369 insertions(+)
 create mode 100644 drivers/usb/misc/brcmstb-usb-pinmap.c

Comments

kernel test robot Oct. 13, 2020, 12:18 a.m. UTC | #1
Hi Al,

I love your patch! Perhaps something to improve:

[auto build test WARNING on usb/usb-testing]
[also build test WARNING on linus/master linux/master v5.9 next-20201012]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Al-Cooper/usb-Add-driver-for-USB-signal-re-mapper/20201013-040257
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
config: arm64-randconfig-r032-20201012 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 9e72d3eaf38f217698f72cb8fdc969a6e72dad3a)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm64 cross compiling tool for clang build
        # apt-get install binutils-aarch64-linux-gnu
        # https://github.com/0day-ci/linux/commit/96c8d52dbcdf6606c03aa54bcb5aece99b9328de
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Al-Cooper/usb-Add-driver-for-USB-signal-re-mapper/20201013-040257
        git checkout 96c8d52dbcdf6606c03aa54bcb5aece99b9328de
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/usb/misc/brcmstb-usb-pinmap.c:219:6: warning: no previous prototype for function 'sync_all_pins' [-Wmissing-prototypes]

   void sync_all_pins(struct brcmstb_usb_pinmap_data *pdata)
        ^
   drivers/usb/misc/brcmstb-usb-pinmap.c:219:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   void sync_all_pins(struct brcmstb_usb_pinmap_data *pdata)
   ^
   static 
   1 warning generated.

vim +/sync_all_pins +219 drivers/usb/misc/brcmstb-usb-pinmap.c

   218	
 > 219	void sync_all_pins(struct brcmstb_usb_pinmap_data *pdata)

   220	{
   221		struct out_pin *pout;
   222		struct in_pin *pin;
   223		int val;
   224		int x;
   225	
   226		/*
   227		 * Enable the override, clear any changed condition and
   228		 * propagate the state to the GPIO for all out pins.
   229		 */
   230		pout = pdata->out_pins;
   231		for (x = 0; x < pdata->out_count; x++) {
   232			pinmap_set(pdata->regs, pout->enable_mask);
   233			pinmap_set(pdata->regs, pout->clr_changed_mask);
   234			pinmap_unset(pdata->regs, pout->clr_changed_mask);
   235			val = readl(pdata->regs) & pout->value_mask;
   236			gpiod_set_value(pout->gpiod, val ? 1 : 0);
   237			pout++;
   238		}
   239	
   240		/* sync and enable all in pins. */
   241		pin = pdata->in_pins;
   242		for (x = 0; x < pdata->in_count; x++) {
   243			sync_in_pin(pin);
   244			pinmap_set(pdata->regs, pin->enable_mask);
   245			pin++;
   246		}
   247	}
   248	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index cd2aea603e03..1198acd71534 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3567,6 +3567,14 @@  S:	Maintained
 F:	Documentation/devicetree/bindings/usb/brcm,bcm7445-ehci.yaml
 F:	drivers/usb/host/ehci-brcm.*
 
+BROADCOM BRCMSTB USB PIN MAP DRIVER
+M:	Al Cooper <alcooperx@gmail.com>
+L:	linux-usb@vger.kernel.org
+L:	bcm-kernel-feedback-list@broadcom.com
+S:	Maintained
+F:	Documentation/devicetree/bindings/usb/brcm,usb-pinmap.yaml
+F:	drivers/usb/misc/brcmstb-usb-pinmap.c
+
 BROADCOM BRCMSTB USB2 and USB3 PHY DRIVER
 M:	Al Cooper <alcooperx@gmail.com>
 L:	linux-kernel@vger.kernel.org
diff --git a/drivers/usb/misc/Kconfig b/drivers/usb/misc/Kconfig
index 6818ea689cd9..8f1144359012 100644
--- a/drivers/usb/misc/Kconfig
+++ b/drivers/usb/misc/Kconfig
@@ -275,3 +275,12 @@  config USB_CHAOSKEY
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called chaoskey.
+
+config BRCM_USB_PINMAP
+	tristate "Broadcom pinmap driver support"
+	depends on (ARCH_BRCMSTB && PHY_BRCM_USB) || COMPILE_TEST
+	default ARCH_BRCMSTB && PHY_BRCM_USB
+	help
+	  This option enables support for remapping some USB external
+	  signals, which are typically on dedicated pins on the chip,
+	  to any gpio.
diff --git a/drivers/usb/misc/Makefile b/drivers/usb/misc/Makefile
index da39bddb0604..5f4e598573ab 100644
--- a/drivers/usb/misc/Makefile
+++ b/drivers/usb/misc/Makefile
@@ -31,3 +31,4 @@  obj-$(CONFIG_USB_CHAOSKEY)		+= chaoskey.o
 
 obj-$(CONFIG_USB_SISUSBVGA)		+= sisusbvga/
 obj-$(CONFIG_USB_LINK_LAYER_TEST)	+= lvstest.o
+obj-$(CONFIG_BRCM_USB_PINMAP)		+= brcmstb-usb-pinmap.o
diff --git a/drivers/usb/misc/brcmstb-usb-pinmap.c b/drivers/usb/misc/brcmstb-usb-pinmap.c
new file mode 100644
index 000000000000..02144c39aaba
--- /dev/null
+++ b/drivers/usb/misc/brcmstb-usb-pinmap.c
@@ -0,0 +1,351 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020, Broadcom */
+
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/device.h>
+#include <linux/of.h>
+#include <linux/kernel.h>
+#include <linux/kdebug.h>
+#include <linux/gpio/consumer.h>
+
+struct out_pin {
+	u32 enable_mask;
+	u32 value_mask;
+	u32 changed_mask;
+	u32 clr_changed_mask;
+	struct gpio_desc *gpiod;
+	const char *name;
+};
+
+struct in_pin {
+	u32 enable_mask;
+	u32 value_mask;
+	struct gpio_desc *gpiod;
+	const char *name;
+	struct brcmstb_usb_pinmap_data *pdata;
+};
+
+struct brcmstb_usb_pinmap_data {
+	void __iomem *regs;
+	int in_count;
+	struct in_pin *in_pins;
+	int out_count;
+	struct out_pin *out_pins;
+};
+
+
+static void pinmap_set(void __iomem *reg, u32 mask)
+{
+	u32 val;
+
+	val = readl(reg);
+	val |= mask;
+	writel(val, reg);
+}
+
+static void pinmap_unset(void __iomem *reg, u32 mask)
+{
+	u32 val;
+
+	val = readl(reg);
+	val &= ~mask;
+	writel(val, reg);
+}
+
+static void sync_in_pin(struct in_pin *pin)
+{
+	u32 val;
+
+	val = gpiod_get_value(pin->gpiod);
+	if (val)
+		pinmap_set(pin->pdata->regs, pin->value_mask);
+	else
+		pinmap_unset(pin->pdata->regs, pin->value_mask);
+}
+
+/*
+ * Interrupt from override register, propagate from override bit
+ * to GPIO.
+ */
+static irqreturn_t brcmstb_usb_pinmap_ovr_isr(int irq, void *dev_id)
+{
+	struct brcmstb_usb_pinmap_data *pdata = dev_id;
+	struct out_pin *pout;
+	u32 val;
+	u32 bit;
+	int x;
+
+	pr_debug("%s: reg: 0x%x\n", __func__, readl(pdata->regs));
+	pout = pdata->out_pins;
+	for (x = 0; x < pdata->out_count; x++) {
+		val = readl(pdata->regs);
+		if (val & pout->changed_mask) {
+			pinmap_set(pdata->regs, pout->clr_changed_mask);
+			pinmap_unset(pdata->regs, pout->clr_changed_mask);
+			bit = val & pout->value_mask;
+			gpiod_set_value(pout->gpiod, bit ? 1 : 0);
+			pr_debug("%s: %s bit changed state to %d\n",
+				 __func__, pout->name, bit ? 1 : 0);
+		}
+	}
+	return IRQ_HANDLED;
+}
+
+/*
+ * Interrupt from GPIO, propagate from GPIO to override bit.
+ */
+static irqreturn_t brcmstb_usb_pinmap_gpio_isr(int irq, void *dev_id)
+{
+	struct in_pin *pin = dev_id;
+
+	pr_debug("%s: %s pin changed state\n", __func__, pin->name);
+	sync_in_pin(pin);
+	return IRQ_HANDLED;
+}
+
+
+static void get_pin_counts(struct device_node *dn, int *in_count,
+			   int *out_count)
+{
+	int in;
+	int out;
+
+	*in_count = 0;
+	*out_count = 0;
+	in = of_property_count_strings(dn, "brcm,in-functions");
+	if (in < 0)
+		return;
+	out = of_property_count_strings(dn, "brcm,out-functions");
+	if (out < 0)
+		return;
+	*in_count = in;
+	*out_count = out;
+}
+
+static int parse_pins(struct device *dev, struct device_node *dn,
+		      struct brcmstb_usb_pinmap_data *pdata)
+{
+	struct out_pin *pout;
+	struct in_pin *pin;
+	int index;
+	int res;
+	int x;
+
+	pin = pdata->in_pins;
+	for (x = 0, index = 0; x < pdata->in_count; x++) {
+		pin->gpiod = devm_gpiod_get_index(dev, "in", x, GPIOD_IN);
+		if (IS_ERR(pin->gpiod)) {
+			dev_err(dev, "Error getting gpio %s\n", pin->name);
+			return PTR_ERR(pin->gpiod);
+
+		}
+		res = of_property_read_string_index(dn, "brcm,in-functions", x,
+						    &pin->name);
+		if (res < 0) {
+			dev_err(dev, "Error getting brcm,in-functions for %s\n",
+				pin->name);
+			return res;
+		}
+		res = of_property_read_u32_index(dn, "brcm,in-masks", index++,
+						 &pin->enable_mask);
+		if (res < 0) {
+			dev_err(dev, "Error getting 1st brcm,in-masks for %s\n",
+				pin->name);
+			return res;
+		}
+		res = of_property_read_u32_index(dn, "brcm,in-masks", index++,
+						 &pin->value_mask);
+		if (res < 0) {
+			dev_err(dev, "Error getting 2nd brcm,in-masks for %s\n",
+				pin->name);
+			return res;
+		}
+		pin->pdata = pdata;
+		pin++;
+	}
+	pout = pdata->out_pins;
+	for (x = 0, index = 0; x < pdata->out_count; x++) {
+		pout->gpiod = devm_gpiod_get_index(dev, "out", x,
+						   GPIOD_OUT_HIGH);
+		if (IS_ERR(pout->gpiod)) {
+			dev_err(dev, "Error getting gpio %s\n", pin->name);
+			return PTR_ERR(pout->gpiod);
+		}
+		res = of_property_read_string_index(dn, "brcm,out-functions", x,
+						    &pout->name);
+		if (res < 0) {
+			dev_err(dev, "Error getting brcm,out-functions for %s\n",
+				pout->name);
+			return res;
+		}
+		res = of_property_read_u32_index(dn, "brcm,out-masks", index++,
+						 &pout->enable_mask);
+		if (res < 0) {
+			dev_err(dev, "Error getting 1st brcm,out-masks for %s\n",
+				pout->name);
+			return res;
+		}
+		res = of_property_read_u32_index(dn, "brcm,out-masks", index++,
+						 &pout->value_mask);
+		if (res < 0) {
+			dev_err(dev, "Error getting 2nd brcm,out-masks for %s\n",
+				pout->name);
+			return res;
+		}
+		res = of_property_read_u32_index(dn, "brcm,out-masks", index++,
+						 &pout->changed_mask);
+		if (res < 0) {
+			dev_err(dev, "Error getting 3rd brcm,out-masks for %s\n",
+				pout->name);
+			return res;
+		}
+		res = of_property_read_u32_index(dn, "brcm,out-masks", index++,
+						 &pout->clr_changed_mask);
+		if (res < 0) {
+			dev_err(dev, "Error getting 4th out-masks for %s\n",
+				pout->name);
+			return res;
+		}
+		pout++;
+	}
+	return 0;
+}
+
+void sync_all_pins(struct brcmstb_usb_pinmap_data *pdata)
+{
+	struct out_pin *pout;
+	struct in_pin *pin;
+	int val;
+	int x;
+
+	/*
+	 * Enable the override, clear any changed condition and
+	 * propagate the state to the GPIO for all out pins.
+	 */
+	pout = pdata->out_pins;
+	for (x = 0; x < pdata->out_count; x++) {
+		pinmap_set(pdata->regs, pout->enable_mask);
+		pinmap_set(pdata->regs, pout->clr_changed_mask);
+		pinmap_unset(pdata->regs, pout->clr_changed_mask);
+		val = readl(pdata->regs) & pout->value_mask;
+		gpiod_set_value(pout->gpiod, val ? 1 : 0);
+		pout++;
+	}
+
+	/* sync and enable all in pins. */
+	pin = pdata->in_pins;
+	for (x = 0; x < pdata->in_count; x++) {
+		sync_in_pin(pin);
+		pinmap_set(pdata->regs, pin->enable_mask);
+		pin++;
+	}
+}
+
+static int __init brcmstb_usb_pinmap_probe(struct platform_device *pdev)
+{
+	struct device_node *dn = pdev->dev.of_node;
+	struct brcmstb_usb_pinmap_data *pdata;
+	struct in_pin *pin;
+	struct resource *r;
+	int out_count;
+	int in_count;
+	int err;
+	int irq;
+	int x;
+
+	get_pin_counts(dn, &in_count, &out_count);
+	if ((in_count + out_count) == 0)
+		return -EINVAL;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	pdata = devm_kzalloc(&pdev->dev,
+			     sizeof(*pdata) +
+			     (sizeof(struct in_pin) * in_count) +
+			     (sizeof(struct out_pin) * out_count), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+
+	pdata->in_count = in_count;
+	pdata->out_count = out_count;
+	pdata->in_pins = (struct in_pin *)(pdata + 1);
+	pdata->out_pins = (struct out_pin *)(pdata->in_pins + in_count);
+
+	pdata->regs = devm_ioremap(&pdev->dev, r->start, resource_size(r));
+	if (IS_ERR(pdata->regs))
+		return PTR_ERR(pdata->regs);
+	platform_set_drvdata(pdev, pdata);
+
+	err = parse_pins(&pdev->dev, dn, pdata);
+	if (err)
+		return err;
+
+	sync_all_pins(pdata);
+
+	if (out_count) {
+
+		/* Enable interrupt for out pins */
+		irq = platform_get_irq(pdev, 0);
+		err = devm_request_irq(&pdev->dev, irq,
+				       brcmstb_usb_pinmap_ovr_isr,
+				       IRQF_TRIGGER_RISING,
+				       pdev->name, pdata);
+		if (err < 0) {
+			dev_err(&pdev->dev, "Error requesting IRQ\n");
+			return err;
+		}
+	}
+
+	for (x = 0, pin = pdata->in_pins; x < pdata->in_count; x++, pin++) {
+		irq = gpiod_to_irq(pin->gpiod);
+		if (irq < 0) {
+			dev_err(&pdev->dev, "Error getting IRQ for %s pin\n",
+				pin->name);
+			return irq;
+		}
+		err = devm_request_irq(&pdev->dev, irq,
+				       brcmstb_usb_pinmap_gpio_isr,
+				       IRQF_SHARED | IRQF_TRIGGER_RISING |
+				       IRQF_TRIGGER_FALLING,
+				       pdev->name, pin);
+		if (err < 0) {
+			dev_err(&pdev->dev, "Error requesting IRQ for %s pin\n",
+				pin->name);
+			return err;
+		}
+	}
+
+	dev_dbg(&pdev->dev, "Driver probe succeeded\n");
+	dev_dbg(&pdev->dev, "In pin count: %d, out pin count: %d\n",
+		pdata->in_count, pdata->out_count);
+	return 0;
+}
+
+
+static const struct of_device_id brcmstb_usb_pinmap_of_match[] = {
+	{ .compatible = "brcm,usb-pinmap" },
+	{ },
+};
+
+static struct platform_driver brcmstb_usb_pinmap_driver = {
+	.driver = {
+		.name	= "brcm-usb-pinmap",
+		.of_match_table = brcmstb_usb_pinmap_of_match,
+	},
+};
+
+static int __init brcmstb_usb_pinmap_init(void)
+{
+	return platform_driver_probe(&brcmstb_usb_pinmap_driver,
+				     brcmstb_usb_pinmap_probe);
+}
+
+module_init(brcmstb_usb_pinmap_init);
+MODULE_AUTHOR("Al Cooper <alcooperx@gmail.com>");
+MODULE_DESCRIPTION("Broadcom USB Pinmap Driver");
+MODULE_LICENSE("GPL");