// SPDX-License-Identifier: GPL-2.0-only /* * linux/arch/arm/mach-pxa/ssp.c * * based on linux/arch/arm/mach-sa1100/ssp.c by Russell King * * Copyright (C) 2003 Russell King. * Copyright (C) 2003 Wolfson Microelectronics PLC * * PXA2xx SSP driver. This provides the generic core for simple * IO-based SSP applications and allows easy port setup for DMA access. * * Author: Liam Girdwood <liam.girdwood@wolfsonmicro.com> */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/errno.h> #include <linux/interrupt.h> #include <linux/ioport.h> #include <linux/init.h> #include <linux/mutex.h> #include <linux/clk.h> #include <linux/err.h> #include <linux/platform_device.h> #include <linux/spi/pxa2xx_spi.h> #include <linux/io.h> #include <linux/of.h> #include <linux/of_device.h> #include <asm/irq.h> static DEFINE_MUTEX(ssp_lock); static LIST_HEAD(ssp_list); struct ssp_device *pxa_ssp_request(int port, const char *label) { struct ssp_device *ssp = NULL; mutex_lock(&ssp_lock); list_for_each_entry(ssp, &ssp_list, node) { if (ssp->port_id == port && ssp->use_count == 0) { ssp->use_count++; ssp->label = label; break; } } mutex_unlock(&ssp_lock); if (&ssp->node == &ssp_list) return NULL; return ssp; } EXPORT_SYMBOL(pxa_ssp_request); struct ssp_device *pxa_ssp_request_of(const struct device_node *of_node, const char *label) { struct ssp_device *ssp = NULL; mutex_lock(&ssp_lock); list_for_each_entry(ssp, &ssp_list, node) { if (ssp->of_node == of_node && ssp->use_count == 0) { ssp->use_count++; ssp->label = label; break; } } mutex_unlock(&ssp_lock); if (&ssp->node == &ssp_list) return NULL; return ssp; } EXPORT_SYMBOL(pxa_ssp_request_of); void pxa_ssp_free(struct ssp_device *ssp) { mutex_lock(&ssp_lock); if (ssp->use_count) { ssp->use_count--; ssp->label = NULL; } else dev_err(ssp->dev, "device already free\n"); mutex_unlock(&ssp_lock); } EXPORT_SYMBOL(pxa_ssp_free); #ifdef CONFIG_OF static const struct of_device_id pxa_ssp_of_ids[] = { { .compatible = "mrvl,pxa25x-ssp", .data = (void *) PXA25x_SSP }, { .compatible = "mvrl,pxa25x-nssp", .data = (void *) PXA25x_NSSP }, { .compatible = "mrvl,pxa27x-ssp", .data = (void *) PXA27x_SSP }, { .compatible = "mrvl,pxa3xx-ssp", .data = (void *) PXA3xx_SSP }, { .compatible = "mvrl,pxa168-ssp", .data = (void *) PXA168_SSP }, { .compatible = "mrvl,pxa910-ssp", .data = (void *) PXA910_SSP }, { .compatible = "mrvl,ce4100-ssp", .data = (void *) CE4100_SSP }, { }, }; MODULE_DEVICE_TABLE(of, pxa_ssp_of_ids); #endif static int pxa_ssp_probe(struct platform_device *pdev) { struct resource *res; struct ssp_device *ssp; struct device *dev = &pdev->dev; ssp = devm_kzalloc(dev, sizeof(struct ssp_device), GFP_KERNEL); if (ssp == NULL) return -ENOMEM; ssp->dev = dev; ssp->clk = devm_clk_get(dev, NULL); if (IS_ERR(ssp->clk)) return PTR_ERR(ssp->clk); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (res == NULL) { dev_err(dev, "no memory resource defined\n"); return -ENODEV; } res = devm_request_mem_region(dev, res->start, resource_size(res), pdev->name); if (res == NULL) { dev_err(dev, "failed to request memory resource\n"); return -EBUSY; } ssp->phys_base = res->start; ssp->mmio_base = devm_ioremap(dev, res->start, resource_size(res)); if (ssp->mmio_base == NULL) { dev_err(dev, "failed to ioremap() registers\n"); return -ENODEV; } ssp->irq = platform_get_irq(pdev, 0); if (ssp->irq < 0) return -ENODEV; if (dev->of_node) { const struct of_device_id *id = of_match_device(of_match_ptr(pxa_ssp_of_ids), dev); ssp->type = (int) id->data; } else { const struct platform_device_id *id = platform_get_device_id(pdev); ssp->type = (int) id->driver_data; /* PXA2xx/3xx SSP ports starts from 1 and the internal pdev->id * starts from 0, do a translation here */ ssp->port_id = pdev->id + 1; } ssp->use_count = 0; ssp->of_node = dev->of_node; mutex_lock(&ssp_lock); list_add(&ssp->node, &ssp_list); mutex_unlock(&ssp_lock); platform_set_drvdata(pdev, ssp); return 0; } static int pxa_ssp_remove(struct platform_device *pdev) { struct ssp_device *ssp = platform_get_drvdata(pdev); mutex_lock(&ssp_lock); list_del(&ssp->node); mutex_unlock(&ssp_lock); return 0; } static const struct platform_device_id ssp_id_table[] = { { "pxa25x-ssp", PXA25x_SSP }, { "pxa25x-nssp", PXA25x_NSSP }, { "pxa27x-ssp", PXA27x_SSP }, { "pxa3xx-ssp", PXA3xx_SSP }, { "pxa168-ssp", PXA168_SSP }, { "pxa910-ssp", PXA910_SSP }, { }, }; static struct platform_driver pxa_ssp_driver = { .probe = pxa_ssp_probe, .remove = pxa_ssp_remove, .driver = { .name = "pxa2xx-ssp", .of_match_table = of_match_ptr(pxa_ssp_of_ids), }, .id_table = ssp_id_table, }; static int __init pxa_ssp_init(void) { return platform_driver_register(&pxa_ssp_driver); } static void __exit pxa_ssp_exit(void) { platform_driver_unregister(&pxa_ssp_driver); } arch_initcall(pxa_ssp_init); module_exit(pxa_ssp_exit); MODULE_DESCRIPTION("PXA SSP driver"); MODULE_AUTHOR("Liam Girdwood"); MODULE_LICENSE("GPL");