1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *  linux/arch/arm/mach-pxa/ssp.c
4 *
5 *  based on linux/arch/arm/mach-sa1100/ssp.c by Russell King
6 *
7 *  Copyright (C) 2003 Russell King.
8 *  Copyright (C) 2003 Wolfson Microelectronics PLC
9 *
10 *  PXA2xx SSP driver.  This provides the generic core for simple
11 *  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	} else
92		dev_err(ssp->dev, "device already free\n");
93	mutex_unlock(&ssp_lock);
94}
95EXPORT_SYMBOL(pxa_ssp_free);
96
97#ifdef CONFIG_OF
98static 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#endif
110
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->id
162		 * starts from 0, do a translation here
163		 */
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