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/*
* 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
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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/io.h>
#include <asm/irq.h>
#include <mach/hardware.h>
#include <plat/ssp.h>
static DEFINE_MUTEX(ssp_lock);
static LIST_HEAD(ssp_list);
struct ssp_device *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(ssp_request);
void ssp_free(struct ssp_device *ssp)
{
mutex_lock(&ssp_lock);
if (ssp->use_count) {
ssp->use_count--;
ssp->label = NULL;
} else
dev_err(&ssp->pdev->dev, "device already free\n");
mutex_unlock(&ssp_lock);
}
EXPORT_SYMBOL(ssp_free);
static int __devinit ssp_probe(struct platform_device *pdev)
{
const struct platform_device_id *id = platform_get_device_id(pdev);
struct resource *res;
struct ssp_device *ssp;
int ret = 0;
ssp = kzalloc(sizeof(struct ssp_device), GFP_KERNEL);
if (ssp == NULL) {
dev_err(&pdev->dev, "failed to allocate memory");
return -ENOMEM;
}
ssp->pdev = pdev;
ssp->clk = clk_get(&pdev->dev, NULL);
if (IS_ERR(ssp->clk)) {
ret = PTR_ERR(ssp->clk);
goto err_free;
}
res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
if (res == NULL) {
dev_err(&pdev->dev, "no SSP RX DRCMR defined\n");
ret = -ENODEV;
goto err_free_clk;
}
ssp->drcmr_rx = res->start;
res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
if (res == NULL) {
dev_err(&pdev->dev, "no SSP TX DRCMR defined\n");
ret = -ENODEV;
goto err_free_clk;
}
ssp->drcmr_tx = res->start;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res == NULL) {
dev_err(&pdev->dev, "no memory resource defined\n");
ret = -ENODEV;
goto err_free_clk;
}
res = request_mem_region(res->start, resource_size(res),
pdev->name);
if (res == NULL) {
dev_err(&pdev->dev, "failed to request memory resource\n");
ret = -EBUSY;
goto err_free_clk;
}
ssp->phys_base = res->start;
ssp->mmio_base = ioremap(res->start, resource_size(res));
if (ssp->mmio_base == NULL) {
dev_err(&pdev->dev, "failed to ioremap() registers\n");
ret = -ENODEV;
goto err_free_mem;
}
ssp->irq = platform_get_irq(pdev, 0);
if (ssp->irq < 0) {
dev_err(&pdev->dev, "no IRQ resource defined\n");
ret = -ENODEV;
goto err_free_io;
}
/* 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->type = (int)id->driver_data;
mutex_lock(&ssp_lock);
list_add(&ssp->node, &ssp_list);
mutex_unlock(&ssp_lock);
platform_set_drvdata(pdev, ssp);
return 0;
err_free_io:
iounmap(ssp->mmio_base);
err_free_mem:
release_mem_region(res->start, resource_size(res));
err_free_clk:
clk_put(ssp->clk);
err_free:
kfree(ssp);
return ret;
}
static int __devexit ssp_remove(struct platform_device *pdev)
{
struct resource *res;
struct ssp_device *ssp;
ssp = platform_get_drvdata(pdev);
if (ssp == NULL)
return -ENODEV;
iounmap(ssp->mmio_base);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
release_mem_region(res->start, resource_size(res));
clk_put(ssp->clk);
mutex_lock(&ssp_lock);
list_del(&ssp->node);
mutex_unlock(&ssp_lock);
kfree(ssp);
return 0;
}
static const struct platform_device_id ssp_id_table[] = {
{ "pxa25x-ssp", PXA25x_SSP },
{ "pxa25x-nssp", PXA25x_NSSP },
{ "pxa27x-ssp", PXA27x_SSP },
{ "pxa168-ssp", PXA168_SSP },
{ },
};
static struct platform_driver ssp_driver = {
.probe = ssp_probe,
.remove = __devexit_p(ssp_remove),
.driver = {
.owner = THIS_MODULE,
.name = "pxa2xx-ssp",
},
.id_table = ssp_id_table,
};
static int __init pxa_ssp_init(void)
{
return platform_driver_register(&ssp_driver);
}
static void __exit pxa_ssp_exit(void)
{
platform_driver_unregister(&ssp_driver);
}
arch_initcall(pxa_ssp_init);
module_exit(pxa_ssp_exit);
MODULE_DESCRIPTION("PXA SSP driver");
MODULE_AUTHOR("Liam Girdwood");
MODULE_LICENSE("GPL");
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