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Diffstat (limited to 'target/linux/bcm27xx/patches-6.1/950-0907-drivers-char-add-generic-gpiomem-driver.patch')
-rw-r--r--target/linux/bcm27xx/patches-6.1/950-0907-drivers-char-add-generic-gpiomem-driver.patch328
1 files changed, 0 insertions, 328 deletions
diff --git a/target/linux/bcm27xx/patches-6.1/950-0907-drivers-char-add-generic-gpiomem-driver.patch b/target/linux/bcm27xx/patches-6.1/950-0907-drivers-char-add-generic-gpiomem-driver.patch
deleted file mode 100644
index 14e6b0a9e4..0000000000
--- a/target/linux/bcm27xx/patches-6.1/950-0907-drivers-char-add-generic-gpiomem-driver.patch
+++ /dev/null
@@ -1,328 +0,0 @@
-From fdf9cab5eaa849e90b12e17718bc47130a91433c Mon Sep 17 00:00:00 2001
-From: Jonathan Bell <jonathan@raspberrypi.com>
-Date: Tue, 25 Apr 2023 15:52:13 +0100
-Subject: [PATCH] drivers: char: add generic gpiomem driver
-
-Based on bcm2835-gpiomem.
-
-We allow export of the "GPIO registers" to userspace via a chardev as
-this allows for finer access control (e.g. users must be group gpio, root
-not required).
-
-This driver allows access to either rp1-gpiomem or gpiomem, depending on
-which nodes are populated in devicetree.
-
-RP1 has a different look-and-feel to BCM283x SoCs as it has split ranges
-for IO controls and the parallel registered OE/IN/OUT access. To handle
-this, the driver concatenates the ranges for an IO bank and the
-corresponding RIO instance into a contiguous buffer.
-
-Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com>
----
- drivers/char/Kconfig | 8 +
- drivers/char/Makefile | 1 +
- drivers/char/raspberrypi-gpiomem.c | 276 +++++++++++++++++++++++++++++
- 3 files changed, 285 insertions(+)
- create mode 100644 drivers/char/raspberrypi-gpiomem.c
-
---- a/drivers/char/Kconfig
-+++ b/drivers/char/Kconfig
-@@ -461,4 +461,12 @@ config RANDOM_TRUST_BOOTLOADER
- believe its RNG facilities may be faulty. This may also be configured
- at boot time with "random.trust_bootloader=on/off".
-
-+config RASPBERRYPI_GPIOMEM
-+ tristate "Rootless GPIO access via mmap() on Raspberry Pi boards"
-+ default n
-+ help
-+ Provides users with root-free access to the GPIO registers
-+ on the board. Calling mmap(/dev/gpiomem) will map the GPIO
-+ register page to the user's pointer.
-+
- endmenu
---- a/drivers/char/Makefile
-+++ b/drivers/char/Makefile
-@@ -46,3 +46,4 @@ obj-$(CONFIG_XILLYBUS_CLASS) += xillybus
- obj-$(CONFIG_POWERNV_OP_PANEL) += powernv-op-panel.o
- obj-$(CONFIG_ADI) += adi.o
- obj-$(CONFIG_BRCM_CHAR_DRIVERS) += broadcom/
-+obj-$(CONFIG_RASPBERRYPI_GPIOMEM) += raspberrypi-gpiomem.o
---- /dev/null
-+++ b/drivers/char/raspberrypi-gpiomem.c
-@@ -0,0 +1,276 @@
-+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
-+/**
-+ * raspberrypi-gpiomem.c
-+ *
-+ * Provides MMIO access to discontiguous section of Device memory as a linear
-+ * user mapping. Successor to bcm2835-gpiomem.c.
-+ *
-+ * Copyright (c) 2023, Raspberry Pi Ltd.
-+ */
-+
-+#include <linux/kernel.h>
-+#include <linux/module.h>
-+#include <linux/of.h>
-+#include <linux/of_device.h>
-+#include <linux/platform_device.h>
-+#include <linux/mm.h>
-+#include <linux/slab.h>
-+#include <linux/cdev.h>
-+#include <linux/pagemap.h>
-+#include <linux/io.h>
-+
-+#define DRIVER_NAME "rpi-gpiomem"
-+#define DEVICE_MINOR 0
-+
-+/*
-+ * Sensible max for a hypothetical "gpio" controller that splits pads,
-+ * IO controls, GPIO in/out/enable, and function selection into different
-+ * ranges. Most use only one or two.
-+ */
-+#define MAX_RANGES 4
-+
-+struct io_windows {
-+ unsigned long phys_base;
-+ unsigned long len;
-+};
-+
-+struct rpi_gpiomem_priv {
-+ dev_t devid;
-+ struct class *class;
-+ struct cdev rpi_gpiomem_cdev;
-+ struct device *dev;
-+ const char *name;
-+ unsigned int nr_wins;
-+ struct io_windows iowins[4];
-+};
-+
-+static int rpi_gpiomem_open(struct inode *inode, struct file *file)
-+{
-+ int dev = iminor(inode);
-+ int ret = 0;
-+ struct rpi_gpiomem_priv *priv;
-+
-+ if (dev != DEVICE_MINOR)
-+ ret = -ENXIO;
-+
-+ priv = container_of(inode->i_cdev, struct rpi_gpiomem_priv,
-+ rpi_gpiomem_cdev);
-+ if (!priv)
-+ return -EINVAL;
-+ file->private_data = priv;
-+ return ret;
-+}
-+
-+static int rpi_gpiomem_release(struct inode *inode, struct file *file)
-+{
-+ int dev = iminor(inode);
-+ int ret = 0;
-+
-+ if (dev != DEVICE_MINOR)
-+ ret = -ENXIO;
-+
-+ return ret;
-+}
-+
-+static const struct vm_operations_struct rpi_gpiomem_vm_ops = {
-+#ifdef CONFIG_HAVE_IOREMAP_PROT
-+ .access = generic_access_phys
-+#endif
-+};
-+
-+static int rpi_gpiomem_mmap(struct file *file, struct vm_area_struct *vma)
-+{
-+ int i;
-+ struct rpi_gpiomem_priv *priv;
-+ unsigned long base;
-+ unsigned long len = 0;
-+ unsigned long offset;
-+
-+ priv = file->private_data;
-+ /*
-+ * Userspace must provide a virtual address space at least
-+ * the size of the concatenated ranges.
-+ */
-+ for (i = 0; i < priv->nr_wins; i++)
-+ len += priv->iowins[i].len;
-+ if (len > vma->vm_end - vma->vm_start + 1)
-+ return -EINVAL;
-+
-+ vma->vm_ops = &rpi_gpiomem_vm_ops;
-+ offset = vma->vm_start;
-+ for (i = 0; i < priv->nr_wins; i++) {
-+ base = priv->iowins[i].phys_base >> PAGE_SHIFT;
-+ len = priv->iowins[i].len;
-+ vma->vm_page_prot = phys_mem_access_prot(file, base, len,
-+ vma->vm_page_prot);
-+ if (remap_pfn_range(vma, offset,
-+ base, len,
-+ vma->vm_page_prot))
-+ break;
-+ offset += len;
-+ }
-+
-+ if (i < priv->nr_wins)
-+ return -EAGAIN;
-+
-+ return 0;
-+}
-+
-+static const struct file_operations rpi_gpiomem_fops = {
-+ .owner = THIS_MODULE,
-+ .open = rpi_gpiomem_open,
-+ .release = rpi_gpiomem_release,
-+ .mmap = rpi_gpiomem_mmap,
-+};
-+
-+static const struct of_device_id rpi_gpiomem_of_match[];
-+
-+static int rpi_gpiomem_probe(struct platform_device *pdev)
-+{
-+ int err, i;
-+ const struct of_device_id *id;
-+ struct device *dev = &pdev->dev;
-+ struct device_node *node = dev->of_node;
-+ struct resource *ioresource;
-+ struct rpi_gpiomem_priv *priv;
-+
-+ /* Allocate buffers and instance data */
-+
-+ priv = kzalloc(sizeof(struct rpi_gpiomem_priv), GFP_KERNEL);
-+
-+ if (!priv) {
-+ err = -ENOMEM;
-+ goto failed_inst_alloc;
-+ }
-+ platform_set_drvdata(pdev, priv);
-+
-+ priv->dev = dev;
-+ id = of_match_device(rpi_gpiomem_of_match, dev);
-+ if (!id)
-+ return -EINVAL;
-+
-+ /*
-+ * Device node naming - for legacy (bcm2835) DT bindings, the driver
-+ * created the node based on a hardcoded name - for new bindings,
-+ * take the node name from DT.
-+ */
-+ if (id == &rpi_gpiomem_of_match[0]) {
-+ priv->name = "gpiomem";
-+ } else {
-+ err = of_property_read_string(node, "chardev-name", &priv->name);
-+ if (err)
-+ return -EINVAL;
-+ }
-+
-+ /*
-+ * Go find the register ranges associated with this instance
-+ */
-+ for (i = 0; i < MAX_RANGES; i++) {
-+ ioresource = platform_get_resource(pdev, IORESOURCE_MEM, i);
-+ if (!ioresource && i == 0) {
-+ dev_err(priv->dev, "failed to get IO resource - no ranges available\n");
-+ err = -ENOENT;
-+ goto failed_get_resource;
-+ }
-+ if (!ioresource)
-+ break;
-+
-+ priv->iowins[i].phys_base = ioresource->start;
-+ priv->iowins[i].len = (ioresource->end + 1) - ioresource->start;
-+ dev_info(&pdev->dev, "window base 0x%08lx size 0x%08lx\n",
-+ priv->iowins[i].phys_base, priv->iowins[i].len);
-+ priv->nr_wins++;
-+ }
-+
-+ /* Create character device entries */
-+
-+ err = alloc_chrdev_region(&priv->devid,
-+ DEVICE_MINOR, 1, priv->name);
-+ if (err != 0) {
-+ dev_err(priv->dev, "unable to allocate device number");
-+ goto failed_alloc_chrdev;
-+ }
-+ cdev_init(&priv->rpi_gpiomem_cdev, &rpi_gpiomem_fops);
-+ priv->rpi_gpiomem_cdev.owner = THIS_MODULE;
-+ err = cdev_add(&priv->rpi_gpiomem_cdev, priv->devid, 1);
-+ if (err != 0) {
-+ dev_err(priv->dev, "unable to register device");
-+ goto failed_cdev_add;
-+ }
-+
-+ /* Create sysfs entries */
-+
-+ priv->class = class_create(THIS_MODULE, priv->name);
-+ if (IS_ERR(priv->class)) {
-+ err = PTR_ERR(priv->class);
-+ goto failed_class_create;
-+ }
-+
-+ dev = device_create(priv->class, NULL, priv->devid, NULL, priv->name);
-+ if (IS_ERR(dev)) {
-+ err = PTR_ERR(dev);
-+ goto failed_device_create;
-+ }
-+
-+ dev_info(priv->dev, "initialised %u regions as /dev/%s\n",
-+ priv->nr_wins, priv->name);
-+
-+ return 0;
-+
-+failed_device_create:
-+ class_destroy(priv->class);
-+failed_class_create:
-+ cdev_del(&priv->rpi_gpiomem_cdev);
-+failed_cdev_add:
-+ unregister_chrdev_region(priv->devid, 1);
-+failed_alloc_chrdev:
-+failed_get_resource:
-+ kfree(priv);
-+failed_inst_alloc:
-+ dev_err(&pdev->dev, "could not load rpi_gpiomem");
-+ return err;
-+}
-+
-+static int rpi_gpiomem_remove(struct platform_device *pdev)
-+{
-+ struct device *dev = &pdev->dev;
-+ struct rpi_gpiomem_priv *priv = platform_get_drvdata(pdev);
-+
-+ device_destroy(priv->class, priv->devid);
-+ class_destroy(priv->class);
-+ cdev_del(&priv->rpi_gpiomem_cdev);
-+ unregister_chrdev_region(priv->devid, 1);
-+ kfree(priv);
-+
-+ dev_info(dev, "%s driver removed - OK", priv->name);
-+ return 0;
-+}
-+
-+static const struct of_device_id rpi_gpiomem_of_match[] = {
-+ {
-+ .compatible = "brcm,bcm2835-gpiomem",
-+ },
-+ {
-+ .compatible = "raspberrypi,gpiomem",
-+ },
-+ { /* sentinel */ },
-+};
-+
-+MODULE_DEVICE_TABLE(of, rpi_gpiomem_of_match);
-+
-+static struct platform_driver rpi_gpiomem_driver = {
-+ .probe = rpi_gpiomem_probe,
-+ .remove = rpi_gpiomem_remove,
-+ .driver = {
-+ .name = DRIVER_NAME,
-+ .owner = THIS_MODULE,
-+ .of_match_table = rpi_gpiomem_of_match,
-+ },
-+};
-+
-+module_platform_driver(rpi_gpiomem_driver);
-+
-+MODULE_ALIAS("platform:rpi-gpiomem");
-+MODULE_LICENSE("Dual BSD/GPL");
-+MODULE_DESCRIPTION("Driver for accessing GPIOs from userspace");
-+MODULE_AUTHOR("Jonathan Bell <jonathan@raspberrypi.com>");
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-12 12:02:12 +0000