+++ /dev/null
-From 0f05af4c96c0272bb431ace33dd284a891e4fe41 Mon Sep 17 00:00:00 2001
-From: popcornmix <popcornmix@gmail.com>
-Date: Tue, 23 Feb 2016 19:56:04 +0000
-Subject: [PATCH] bcm2835-virtgpio: Virtual GPIO driver
-
-Add a virtual GPIO driver that uses the firmware mailbox interface to
-request that the VPU toggles LEDs.
----
- drivers/gpio/Kconfig | 6 +
- drivers/gpio/Makefile | 1 +
- drivers/gpio/gpio-bcm-virt.c | 214 +++++++++++++++++++++++++++++++++++
- 3 files changed, 221 insertions(+)
- create mode 100644 drivers/gpio/gpio-bcm-virt.c
-
---- a/drivers/gpio/Kconfig
-+++ b/drivers/gpio/Kconfig
-@@ -151,6 +151,12 @@ config GPIO_BCM_KONA
- help
- Turn on GPIO support for Broadcom "Kona" chips.
-
-+config GPIO_BCM_VIRT
-+ bool "Broadcom Virt GPIO"
-+ depends on OF_GPIO && RASPBERRYPI_FIRMWARE && (ARCH_BCM2835 || COMPILE_TEST)
-+ help
-+ Turn on virtual GPIO support for Broadcom BCM283X chips.
-+
- config GPIO_BRCMSTB
- tristate "BRCMSTB GPIO support"
- default y if (ARCH_BRCMSTB || BMIPS_GENERIC)
---- a/drivers/gpio/Makefile
-+++ b/drivers/gpio/Makefile
-@@ -35,6 +35,7 @@ obj-$(CONFIG_GPIO_ASPEED) += gpio-aspeed
- obj-$(CONFIG_GPIO_RASPBERRYPI_EXP) += gpio-raspberrypi-exp.o
- obj-$(CONFIG_GPIO_BCM_KONA) += gpio-bcm-kona.o
- obj-$(CONFIG_GPIO_BD9571MWV) += gpio-bd9571mwv.o
-+obj-$(CONFIG_GPIO_BCM_VIRT) += gpio-bcm-virt.o
- obj-$(CONFIG_GPIO_BRCMSTB) += gpio-brcmstb.o
- obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o
- obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o
---- /dev/null
-+++ b/drivers/gpio/gpio-bcm-virt.c
-@@ -0,0 +1,214 @@
-+/*
-+ * brcmvirt GPIO driver
-+ *
-+ * Copyright (C) 2012,2013 Dom Cobley <popcornmix@gmail.com>
-+ * Based on gpio-clps711x.c by Alexander Shiyan <shc_work@mail.ru>
-+ *
-+ * This program is free software; you can redistribute it and/or modify
-+ * it under the terms of the GNU General Public License as published by
-+ * the Free Software Foundation; either version 2 of the License, or
-+ * (at your option) any later version.
-+ */
-+
-+#include <linux/err.h>
-+#include <linux/gpio.h>
-+#include <linux/module.h>
-+#include <linux/platform_device.h>
-+#include <linux/dma-mapping.h>
-+#include <soc/bcm2835/raspberrypi-firmware.h>
-+
-+#define MODULE_NAME "brcmvirt-gpio"
-+#define NUM_GPIO 2
-+
-+struct brcmvirt_gpio {
-+ struct gpio_chip gc;
-+ u32 __iomem *ts_base;
-+ /* two packed 16-bit counts of enabled and disables
-+ Allows host to detect a brief enable that was missed */
-+ u32 enables_disables[NUM_GPIO];
-+ dma_addr_t bus_addr;
-+};
-+
-+static int brcmvirt_gpio_dir_in(struct gpio_chip *gc, unsigned off)
-+{
-+ struct brcmvirt_gpio *gpio;
-+ gpio = container_of(gc, struct brcmvirt_gpio, gc);
-+ return -EINVAL;
-+}
-+
-+static int brcmvirt_gpio_dir_out(struct gpio_chip *gc, unsigned off, int val)
-+{
-+ struct brcmvirt_gpio *gpio;
-+ gpio = container_of(gc, struct brcmvirt_gpio, gc);
-+ return 0;
-+}
-+
-+static int brcmvirt_gpio_get(struct gpio_chip *gc, unsigned off)
-+{
-+ struct brcmvirt_gpio *gpio;
-+ unsigned v;
-+ gpio = container_of(gc, struct brcmvirt_gpio, gc);
-+ v = readl(gpio->ts_base + off);
-+ return (v >> off) & 1;
-+}
-+
-+static void brcmvirt_gpio_set(struct gpio_chip *gc, unsigned off, int val)
-+{
-+ struct brcmvirt_gpio *gpio;
-+ u16 enables, disables;
-+ s16 diff;
-+ bool lit;
-+ gpio = container_of(gc, struct brcmvirt_gpio, gc);
-+ enables = gpio->enables_disables[off] >> 16;
-+ disables = gpio->enables_disables[off] >> 0;
-+ diff = (s16)(enables - disables);
-+ lit = diff > 0;
-+ if ((val && lit) || (!val && !lit))
-+ return;
-+ if (val)
-+ enables++;
-+ else
-+ disables++;
-+ diff = (s16)(enables - disables);
-+ BUG_ON(diff != 0 && diff != 1);
-+ gpio->enables_disables[off] = (enables << 16) | (disables << 0);
-+ writel(gpio->enables_disables[off], gpio->ts_base + off);
-+}
-+
-+static int brcmvirt_gpio_probe(struct platform_device *pdev)
-+{
-+ int err = 0;
-+ struct device *dev = &pdev->dev;
-+ struct device_node *np = dev->of_node;
-+ struct device_node *fw_node;
-+ struct rpi_firmware *fw;
-+ struct brcmvirt_gpio *ucb;
-+ u32 gpiovirtbuf;
-+
-+ fw_node = of_parse_phandle(np, "firmware", 0);
-+ if (!fw_node) {
-+ dev_err(dev, "Missing firmware node\n");
-+ return -ENOENT;
-+ }
-+
-+ fw = rpi_firmware_get(fw_node);
-+ if (!fw)
-+ return -EPROBE_DEFER;
-+
-+ ucb = devm_kzalloc(dev, sizeof *ucb, GFP_KERNEL);
-+ if (!ucb) {
-+ err = -EINVAL;
-+ goto out;
-+ }
-+
-+ ucb->ts_base = dma_zalloc_coherent(dev, PAGE_SIZE, &ucb->bus_addr, GFP_KERNEL);
-+ if (!ucb->ts_base) {
-+ pr_err("[%s]: failed to dma_alloc_coherent(%ld)\n",
-+ __func__, PAGE_SIZE);
-+ err = -ENOMEM;
-+ goto out;
-+ }
-+
-+ gpiovirtbuf = (u32)ucb->bus_addr;
-+ err = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_SET_GPIOVIRTBUF,
-+ &gpiovirtbuf, sizeof(gpiovirtbuf));
-+
-+ if (err || gpiovirtbuf != 0) {
-+ dev_warn(dev, "Failed to set gpiovirtbuf, trying to get err:%x\n", err);
-+ dma_free_coherent(dev, PAGE_SIZE, ucb->ts_base, ucb->bus_addr);
-+ ucb->ts_base = 0;
-+ ucb->bus_addr = 0;
-+ }
-+
-+ if (!ucb->ts_base) {
-+ err = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_GET_GPIOVIRTBUF,
-+ &gpiovirtbuf, sizeof(gpiovirtbuf));
-+
-+ if (err) {
-+ dev_err(dev, "Failed to get gpiovirtbuf\n");
-+ goto out;
-+ }
-+
-+ if (!gpiovirtbuf) {
-+ dev_err(dev, "No virtgpio buffer\n");
-+ err = -ENOENT;
-+ goto out;
-+ }
-+
-+ // mmap the physical memory
-+ gpiovirtbuf &= ~0xc0000000;
-+ ucb->ts_base = ioremap(gpiovirtbuf, 4096);
-+ if (ucb->ts_base == NULL) {
-+ dev_err(dev, "Failed to map physical address\n");
-+ err = -ENOENT;
-+ goto out;
-+ }
-+ ucb->bus_addr = 0;
-+ }
-+ ucb->gc.label = MODULE_NAME;
-+ ucb->gc.owner = THIS_MODULE;
-+ //ucb->gc.dev = dev;
-+ ucb->gc.of_node = np;
-+ ucb->gc.base = 100;
-+ ucb->gc.ngpio = NUM_GPIO;
-+
-+ ucb->gc.direction_input = brcmvirt_gpio_dir_in;
-+ ucb->gc.direction_output = brcmvirt_gpio_dir_out;
-+ ucb->gc.get = brcmvirt_gpio_get;
-+ ucb->gc.set = brcmvirt_gpio_set;
-+ ucb->gc.can_sleep = true;
-+
-+ err = gpiochip_add(&ucb->gc);
-+ if (err)
-+ goto out;
-+
-+ platform_set_drvdata(pdev, ucb);
-+
-+ return 0;
-+out:
-+ if (ucb->bus_addr) {
-+ dma_free_coherent(dev, PAGE_SIZE, ucb->ts_base, ucb->bus_addr);
-+ ucb->bus_addr = 0;
-+ ucb->ts_base = NULL;
-+ } else if (ucb->ts_base) {
-+ iounmap(ucb->ts_base);
-+ ucb->ts_base = NULL;
-+ }
-+ return err;
-+}
-+
-+static int brcmvirt_gpio_remove(struct platform_device *pdev)
-+{
-+ struct device *dev = &pdev->dev;
-+ int err = 0;
-+ struct brcmvirt_gpio *ucb = platform_get_drvdata(pdev);
-+
-+ gpiochip_remove(&ucb->gc);
-+ if (ucb->bus_addr)
-+ dma_free_coherent(dev, PAGE_SIZE, ucb->ts_base, ucb->bus_addr);
-+ else if (ucb->ts_base)
-+ iounmap(ucb->ts_base);
-+ return err;
-+}
-+
-+static const struct of_device_id __maybe_unused brcmvirt_gpio_ids[] = {
-+ { .compatible = "brcm,bcm2835-virtgpio" },
-+ { }
-+};
-+MODULE_DEVICE_TABLE(of, brcmvirt_gpio_ids);
-+
-+static struct platform_driver brcmvirt_gpio_driver = {
-+ .driver = {
-+ .name = MODULE_NAME,
-+ .owner = THIS_MODULE,
-+ .of_match_table = of_match_ptr(brcmvirt_gpio_ids),
-+ },
-+ .probe = brcmvirt_gpio_probe,
-+ .remove = brcmvirt_gpio_remove,
-+};
-+module_platform_driver(brcmvirt_gpio_driver);
-+
-+MODULE_LICENSE("GPL");
-+MODULE_AUTHOR("Dom Cobley <popcornmix@gmail.com>");
-+MODULE_DESCRIPTION("brcmvirt GPIO driver");
-+MODULE_ALIAS("platform:brcmvirt-gpio");
projects / openwrt / openwrt.git / blobdiff