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Diffstat (limited to 'arch/arm/plat-pxa/ssp.c')
-rw-r--r--arch/arm/plat-pxa/ssp.c223
1 files changed, 223 insertions, 0 deletions
diff --git a/arch/arm/plat-pxa/ssp.c b/arch/arm/plat-pxa/ssp.c
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+++ b/arch/arm/plat-pxa/ssp.c
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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_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, res->end - res->start + 1,
+ 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, res->end - res->start + 1);
+ 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;
+ }
+
+ 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_io;
+ }
+ 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_io;
+ }
+ ssp->drcmr_tx = res->start;
+
+ /* 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, res->end - res->start + 1);
+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, res->end - res->start + 1);
+
+ 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 },
+ { },
+};
+
+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");