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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * linux/arch/arm/mach-pxa/ssp.c4 *5 * based on linux/arch/arm/mach-sa1100/ssp.c by Russell King6 *7 * Copyright (C) 2003 Russell King.8 * Copyright (C) 2003 Wolfson Microelectronics PLC9 *10 * PXA2xx SSP driver. This provides the generic core for simple11 * IO-based SSP applications and allows easy port setup for DMA access.12 *13 * Author: Liam Girdwood <liam.girdwood@wolfsonmicro.com>14 */15 16#include <linux/module.h>17#include <linux/kernel.h>18#include <linux/sched.h>19#include <linux/slab.h>20#include <linux/errno.h>21#include <linux/interrupt.h>22#include <linux/ioport.h>23#include <linux/init.h>24#include <linux/mutex.h>25#include <linux/clk.h>26#include <linux/err.h>27#include <linux/platform_device.h>28#include <linux/pxa2xx_ssp.h>29#include <linux/io.h>30#include <linux/of.h>31#include <linux/of_device.h>32 33#include <asm/irq.h>34 35static DEFINE_MUTEX(ssp_lock);36static LIST_HEAD(ssp_list);37 38struct ssp_device *pxa_ssp_request(int port, const char *label)39{40 struct ssp_device *ssp = NULL;41 42 mutex_lock(&ssp_lock);43 44 list_for_each_entry(ssp, &ssp_list, node) {45 if (ssp->port_id == port && ssp->use_count == 0) {46 ssp->use_count++;47 ssp->label = label;48 break;49 }50 }51 52 mutex_unlock(&ssp_lock);53 54 if (&ssp->node == &ssp_list)55 return NULL;56 57 return ssp;58}59EXPORT_SYMBOL(pxa_ssp_request);60 61struct ssp_device *pxa_ssp_request_of(const struct device_node *of_node,62 const char *label)63{64 struct ssp_device *ssp = NULL;65 66 mutex_lock(&ssp_lock);67 68 list_for_each_entry(ssp, &ssp_list, node) {69 if (ssp->of_node == of_node && ssp->use_count == 0) {70 ssp->use_count++;71 ssp->label = label;72 break;73 }74 }75 76 mutex_unlock(&ssp_lock);77 78 if (&ssp->node == &ssp_list)79 return NULL;80 81 return ssp;82}83EXPORT_SYMBOL(pxa_ssp_request_of);84 85void pxa_ssp_free(struct ssp_device *ssp)86{87 mutex_lock(&ssp_lock);88 if (ssp->use_count) {89 ssp->use_count--;90 ssp->label = NULL;91 } else92 dev_err(ssp->dev, "device already free\n");93 mutex_unlock(&ssp_lock);94}95EXPORT_SYMBOL(pxa_ssp_free);96 97#ifdef CONFIG_OF98static const struct of_device_id pxa_ssp_of_ids[] = {99 { .compatible = "mrvl,pxa25x-ssp", .data = (void *) PXA25x_SSP },100 { .compatible = "mvrl,pxa25x-nssp", .data = (void *) PXA25x_NSSP },101 { .compatible = "mrvl,pxa27x-ssp", .data = (void *) PXA27x_SSP },102 { .compatible = "mrvl,pxa3xx-ssp", .data = (void *) PXA3xx_SSP },103 { .compatible = "mvrl,pxa168-ssp", .data = (void *) PXA168_SSP },104 { .compatible = "mrvl,pxa910-ssp", .data = (void *) PXA910_SSP },105 { .compatible = "mrvl,ce4100-ssp", .data = (void *) CE4100_SSP },106 { },107};108MODULE_DEVICE_TABLE(of, pxa_ssp_of_ids);109#endif110 111static int pxa_ssp_probe(struct platform_device *pdev)112{113 struct resource *res;114 struct ssp_device *ssp;115 struct device *dev = &pdev->dev;116 117 ssp = devm_kzalloc(dev, sizeof(struct ssp_device), GFP_KERNEL);118 if (ssp == NULL)119 return -ENOMEM;120 121 ssp->dev = dev;122 123 ssp->clk = devm_clk_get(dev, NULL);124 if (IS_ERR(ssp->clk))125 return PTR_ERR(ssp->clk);126 127 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);128 if (res == NULL) {129 dev_err(dev, "no memory resource defined\n");130 return -ENODEV;131 }132 133 res = devm_request_mem_region(dev, res->start, resource_size(res),134 pdev->name);135 if (res == NULL) {136 dev_err(dev, "failed to request memory resource\n");137 return -EBUSY;138 }139 140 ssp->phys_base = res->start;141 142 ssp->mmio_base = devm_ioremap(dev, res->start, resource_size(res));143 if (ssp->mmio_base == NULL) {144 dev_err(dev, "failed to ioremap() registers\n");145 return -ENODEV;146 }147 148 ssp->irq = platform_get_irq(pdev, 0);149 if (ssp->irq < 0)150 return -ENODEV;151 152 if (dev->of_node) {153 const struct of_device_id *id =154 of_match_device(of_match_ptr(pxa_ssp_of_ids), dev);155 ssp->type = (uintptr_t) id->data;156 } else {157 const struct platform_device_id *id =158 platform_get_device_id(pdev);159 ssp->type = id->driver_data;160 161 /* PXA2xx/3xx SSP ports starts from 1 and the internal pdev->id162 * starts from 0, do a translation here163 */164 ssp->port_id = pdev->id + 1;165 }166 167 ssp->use_count = 0;168 ssp->of_node = dev->of_node;169 170 mutex_lock(&ssp_lock);171 list_add(&ssp->node, &ssp_list);172 mutex_unlock(&ssp_lock);173 174 platform_set_drvdata(pdev, ssp);175 176 return 0;177}178 179static void pxa_ssp_remove(struct platform_device *pdev)180{181 struct ssp_device *ssp = platform_get_drvdata(pdev);182 183 mutex_lock(&ssp_lock);184 list_del(&ssp->node);185 mutex_unlock(&ssp_lock);186}187 188static const struct platform_device_id ssp_id_table[] = {189 { "pxa25x-ssp", PXA25x_SSP },190 { "pxa25x-nssp", PXA25x_NSSP },191 { "pxa27x-ssp", PXA27x_SSP },192 { "pxa3xx-ssp", PXA3xx_SSP },193 { "pxa168-ssp", PXA168_SSP },194 { "pxa910-ssp", PXA910_SSP },195 { },196};197 198static struct platform_driver pxa_ssp_driver = {199 .probe = pxa_ssp_probe,200 .remove_new = pxa_ssp_remove,201 .driver = {202 .name = "pxa2xx-ssp",203 .of_match_table = of_match_ptr(pxa_ssp_of_ids),204 },205 .id_table = ssp_id_table,206};207 208static int __init pxa_ssp_init(void)209{210 return platform_driver_register(&pxa_ssp_driver);211}212 213static void __exit pxa_ssp_exit(void)214{215 platform_driver_unregister(&pxa_ssp_driver);216}217 218arch_initcall(pxa_ssp_init);219module_exit(pxa_ssp_exit);220 221MODULE_DESCRIPTION("PXA SSP driver");222MODULE_AUTHOR("Liam Girdwood");223MODULE_LICENSE("GPL");224