4 * Copyright (C) 2007 Atmel Corporation
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
11 #include <linux/platform_device.h>
12 #include <linux/list.h>
13 #include <linux/clk.h>
14 #include <linux/err.h>
16 #include <linux/spinlock.h>
17 #include <linux/atmel-ssc.h>
18 #include <linux/slab.h>
19 #include <linux/module.h>
22 #include <linux/pinctrl/consumer.h>
24 /* Serialize access to ssc_list and user count */
25 static DEFINE_SPINLOCK(user_lock
);
26 static LIST_HEAD(ssc_list
);
28 struct ssc_device
*ssc_request(unsigned int ssc_num
)
31 struct ssc_device
*ssc
;
33 spin_lock(&user_lock
);
34 list_for_each_entry(ssc
, &ssc_list
, list
) {
35 if (ssc
->pdev
->dev
.of_node
) {
36 if (of_alias_get_id(ssc
->pdev
->dev
.of_node
, "ssc")
41 } else if (ssc
->pdev
->id
== ssc_num
) {
48 spin_unlock(&user_lock
);
49 pr_err("ssc: ssc%d platform device is missing\n", ssc_num
);
50 return ERR_PTR(-ENODEV
);
54 spin_unlock(&user_lock
);
55 dev_dbg(&ssc
->pdev
->dev
, "module busy\n");
56 return ERR_PTR(-EBUSY
);
59 spin_unlock(&user_lock
);
61 clk_prepare_enable(ssc
->clk
);
65 EXPORT_SYMBOL(ssc_request
);
67 void ssc_free(struct ssc_device
*ssc
)
69 bool disable_clk
= true;
71 spin_lock(&user_lock
);
76 dev_dbg(&ssc
->pdev
->dev
, "device already free\n");
78 spin_unlock(&user_lock
);
81 clk_disable_unprepare(ssc
->clk
);
83 EXPORT_SYMBOL(ssc_free
);
85 static struct atmel_ssc_platform_data at91rm9200_config
= {
89 static struct atmel_ssc_platform_data at91sam9g45_config
= {
93 static const struct platform_device_id atmel_ssc_devtypes
[] = {
95 .name
= "at91rm9200_ssc",
96 .driver_data
= (unsigned long) &at91rm9200_config
,
98 .name
= "at91sam9g45_ssc",
99 .driver_data
= (unsigned long) &at91sam9g45_config
,
106 static const struct of_device_id atmel_ssc_dt_ids
[] = {
108 .compatible
= "atmel,at91rm9200-ssc",
109 .data
= &at91rm9200_config
,
111 .compatible
= "atmel,at91sam9g45-ssc",
112 .data
= &at91sam9g45_config
,
117 MODULE_DEVICE_TABLE(of
, atmel_ssc_dt_ids
);
120 static inline const struct atmel_ssc_platform_data
* __init
121 atmel_ssc_get_driver_data(struct platform_device
*pdev
)
123 if (pdev
->dev
.of_node
) {
124 const struct of_device_id
*match
;
125 match
= of_match_node(atmel_ssc_dt_ids
, pdev
->dev
.of_node
);
131 return (struct atmel_ssc_platform_data
*)
132 platform_get_device_id(pdev
)->driver_data
;
135 static int ssc_probe(struct platform_device
*pdev
)
137 struct resource
*regs
;
138 struct ssc_device
*ssc
;
139 const struct atmel_ssc_platform_data
*plat_dat
;
140 struct pinctrl
*pinctrl
;
142 pinctrl
= devm_pinctrl_get_select_default(&pdev
->dev
);
143 if (IS_ERR(pinctrl
)) {
144 dev_err(&pdev
->dev
, "Failed to request pinctrl\n");
145 return PTR_ERR(pinctrl
);
148 ssc
= devm_kzalloc(&pdev
->dev
, sizeof(struct ssc_device
), GFP_KERNEL
);
150 dev_dbg(&pdev
->dev
, "out of memory\n");
156 plat_dat
= atmel_ssc_get_driver_data(pdev
);
159 ssc
->pdata
= (struct atmel_ssc_platform_data
*)plat_dat
;
161 regs
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
162 ssc
->regs
= devm_ioremap_resource(&pdev
->dev
, regs
);
163 if (IS_ERR(ssc
->regs
))
164 return PTR_ERR(ssc
->regs
);
166 ssc
->phybase
= regs
->start
;
168 ssc
->clk
= devm_clk_get(&pdev
->dev
, "pclk");
169 if (IS_ERR(ssc
->clk
)) {
170 dev_dbg(&pdev
->dev
, "no pclk clock defined\n");
174 /* disable all interrupts */
175 clk_prepare_enable(ssc
->clk
);
176 ssc_writel(ssc
->regs
, IDR
, -1);
177 ssc_readl(ssc
->regs
, SR
);
178 clk_disable_unprepare(ssc
->clk
);
180 ssc
->irq
= platform_get_irq(pdev
, 0);
182 dev_dbg(&pdev
->dev
, "could not get irq\n");
186 spin_lock(&user_lock
);
187 list_add_tail(&ssc
->list
, &ssc_list
);
188 spin_unlock(&user_lock
);
190 platform_set_drvdata(pdev
, ssc
);
192 dev_info(&pdev
->dev
, "Atmel SSC device at 0x%p (irq %d)\n",
193 ssc
->regs
, ssc
->irq
);
198 static int ssc_remove(struct platform_device
*pdev
)
200 struct ssc_device
*ssc
= platform_get_drvdata(pdev
);
202 spin_lock(&user_lock
);
203 list_del(&ssc
->list
);
204 spin_unlock(&user_lock
);
209 static struct platform_driver ssc_driver
= {
212 .owner
= THIS_MODULE
,
213 .of_match_table
= of_match_ptr(atmel_ssc_dt_ids
),
215 .id_table
= atmel_ssc_devtypes
,
217 .remove
= ssc_remove
,
219 module_platform_driver(ssc_driver
);
221 MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
222 MODULE_DESCRIPTION("SSC driver for Atmel AVR32 and AT91");
223 MODULE_LICENSE("GPL");
224 MODULE_ALIAS("platform:ssc");