diff options
Diffstat (limited to 'drivers/staging/xroeframer/xroe_framer.c')
| -rw-r--r-- | drivers/staging/xroeframer/xroe_framer.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/drivers/staging/xroeframer/xroe_framer.c b/drivers/staging/xroeframer/xroe_framer.c new file mode 100644 index 000000000000..dba7c69b010f --- /dev/null +++ b/drivers/staging/xroeframer/xroe_framer.c @@ -0,0 +1,155 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Xilinx, Inc. + * + * Vasileios Bimpikas <vasileios.bimpikas@xilinx.com> + */ +#include <linux/cdev.h> +#include <linux/device.h> +#include <linux/errno.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of_address.h> +#include <linux/of_device.h> +#include <linux/of_platform.h> +#include <linux/slab.h> +#include <linux/uaccess.h> +#include "xroe_framer.h" + +#define DRIVER_NAME "framer" + +/* + * TODO: to be made static as well, so that multiple instances can be used. As + * of now, the "lp" structure is shared among the multiple source files + */ +struct framer_local *lp; +static struct platform_driver framer_driver; +/* + * TODO: placeholder for the IRQ once it's been implemented + * in the framer block + */ +static irqreturn_t framer_irq(int irq, void *lp) +{ + return IRQ_HANDLED; +} + +/** + * framer_probe - Probes the device tree to locate the framer block + * @pdev: The structure containing the device's details + * + * Probes the device tree to locate the framer block and maps it to + * the kernel virtual memory space + * + * Return: 0 on success or a negative errno on error. + */ +static int framer_probe(struct platform_device *pdev) +{ + struct resource *r_mem; /* IO mem resources */ + struct resource *r_irq; + struct device *dev = &pdev->dev; + int rc = 0; + + dev_dbg(dev, "Device Tree Probing\n"); + lp = devm_kzalloc(&pdev->dev, sizeof(*lp), GFP_KERNEL); + if (!lp) + return -ENOMEM; + + /* Get iospace for the device */ + r_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + lp->base_addr = devm_ioremap_resource(&pdev->dev, r_mem); + if (IS_ERR(lp->base_addr)) + return PTR_ERR(lp->base_addr); + + dev_set_drvdata(dev, lp); + xroe_sysfs_init(); + /* Get IRQ for the device */ + /* + * TODO: No IRQ *yet* in the DT from the framer block, as it's still + * under development. To be added once it's in the block, and also + * replace with platform_get_irq_byname() + */ + r_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0); + if (IS_ERR(r_irq)) { + dev_info(dev, "no IRQ found\n"); + /* + * TODO: Return non-zero (error) code on no IRQ found. + * To be implemented once the IRQ is in the block + */ + return 0; + } + rc = devm_request_irq(dev, lp->irq, &framer_irq, 0, DRIVER_NAME, lp); + if (rc) { + dev_err(dev, "testmodule: Could not allocate interrupt %d.\n", + lp->irq); + /* + * TODO: Return non-zero (error) code on no IRQ found. + * To be implemented once the IRQ is in the block + */ + return 0; + } + + return rc; +} + +/** + * framer_init - Registers the driver + * + * Return: 0 on success, -1 on allocation error + * + * Registers the framer driver and creates character device drivers + * for the whole block, as well as separate ones for stats and + * radio control. + */ +static int __init framer_init(void) +{ + int ret; + + pr_debug("XROE framer driver init\n"); + + ret = platform_driver_register(&framer_driver); + + return ret; +} + +/** + * framer_exit - Destroys the driver + * + * Unregisters the framer driver and destroys the character + * device driver for the whole block, as well as the separate ones + * for stats and radio control. Returns 0 upon successful execution + */ +static void __exit framer_exit(void) +{ + xroe_sysfs_exit(); + platform_driver_unregister(&framer_driver); + pr_info("XROE Framer exit\n"); +} + +module_init(framer_init); +module_exit(framer_exit); + +static const struct of_device_id framer_of_match[] = { + { .compatible = "xlnx,roe-framer-1.0", }, + { /* end of list */ }, +}; +MODULE_DEVICE_TABLE(of, framer_of_match); + +static struct platform_driver framer_driver = { + .driver = { + /* + * TODO: .name shouldn't be necessary, though removing + * it results in kernel panic. To investigate further + */ + .name = DRIVER_NAME, + .of_match_table = framer_of_match, + }, + .probe = framer_probe, +}; + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Xilinx Inc."); +MODULE_DESCRIPTION("framer - Xilinx Radio over Ethernet Framer driver"); |