--- /dev/null
+/*
+ * Atmel SSC driver
+ *
+ * Copyright (C) 2007 Atmel Corporation
+ *
+ * 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.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/list.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/atmel-ssc.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#include <linux/of.h>
+
+/* Serialize access to ssc_list and user count */
+static DEFINE_SPINLOCK(user_lock);
+static LIST_HEAD(ssc_list);
+
+struct ssc_device *ssc_request(unsigned int ssc_num)
+{
+ int ssc_valid = 0;
+ struct ssc_device *ssc;
+
+ spin_lock(&user_lock);
+ list_for_each_entry(ssc, &ssc_list, list) {
+ if (ssc->pdev->dev.of_node) {
+ if (of_alias_get_id(ssc->pdev->dev.of_node, "ssc")
+ == ssc_num) {
+ ssc_valid = 1;
+ break;
+ }
+ } else if (ssc->pdev->id == ssc_num) {
+ ssc_valid = 1;
+ break;
+ }
+ }
+
+ if (!ssc_valid) {
+ spin_unlock(&user_lock);
+ pr_err("ssc: ssc%d platform device is missing\n", ssc_num);
+ return ERR_PTR(-ENODEV);
+ }
+
+ if (ssc->user) {
+ spin_unlock(&user_lock);
+ dev_dbg(&ssc->pdev->dev, "module busy\n");
+ return ERR_PTR(-EBUSY);
+ }
+ ssc->user++;
+ spin_unlock(&user_lock);
+
+ clk_prepare(ssc->clk);
+
+ return ssc;
+}
+EXPORT_SYMBOL(ssc_request);
+
+void ssc_free(struct ssc_device *ssc)
+{
+ bool disable_clk = true;
+
+ spin_lock(&user_lock);
+ if (ssc->user)
+ ssc->user--;
+ else {
+ disable_clk = false;
+ dev_dbg(&ssc->pdev->dev, "device already free\n");
+ }
+ spin_unlock(&user_lock);
+
+ if (disable_clk)
+ clk_unprepare(ssc->clk);
+}
+EXPORT_SYMBOL(ssc_free);
+
+static struct atmel_ssc_platform_data at91rm9200_config = {
+ .use_dma = 0,
+ .has_fslen_ext = 0,
+};
+
+static struct atmel_ssc_platform_data at91sam9rl_config = {
+ .use_dma = 0,
+ .has_fslen_ext = 1,
+};
+
+static struct atmel_ssc_platform_data at91sam9g45_config = {
+ .use_dma = 1,
+ .has_fslen_ext = 1,
+};
+
+static const struct platform_device_id atmel_ssc_devtypes[] = {
+ {
+ .name = "at91rm9200_ssc",
+ .driver_data = (unsigned long) &at91rm9200_config,
+ }, {
+ .name = "at91sam9rl_ssc",
+ .driver_data = (unsigned long) &at91sam9rl_config,
+ }, {
+ .name = "at91sam9g45_ssc",
+ .driver_data = (unsigned long) &at91sam9g45_config,
+ }, {
+ /* sentinel */
+ }
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id atmel_ssc_dt_ids[] = {
+ {
+ .compatible = "atmel,at91rm9200-ssc",
+ .data = &at91rm9200_config,
+ }, {
+ .compatible = "atmel,at91sam9rl-ssc",
+ .data = &at91sam9rl_config,
+ }, {
+ .compatible = "atmel,at91sam9g45-ssc",
+ .data = &at91sam9g45_config,
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, atmel_ssc_dt_ids);
+#endif
+
+static inline const struct atmel_ssc_platform_data * __init
+ atmel_ssc_get_driver_data(struct platform_device *pdev)
+{
+ if (pdev->dev.of_node) {
+ const struct of_device_id *match;
+ match = of_match_node(atmel_ssc_dt_ids, pdev->dev.of_node);
+ if (match == NULL)
+ return NULL;
+ return match->data;
+ }
+
+ return (struct atmel_ssc_platform_data *)
+ platform_get_device_id(pdev)->driver_data;
+}
+
+static int ssc_probe(struct platform_device *pdev)
+{
+ struct resource *regs;
+ struct ssc_device *ssc;
+ const struct atmel_ssc_platform_data *plat_dat;
+
+ ssc = devm_kzalloc(&pdev->dev, sizeof(struct ssc_device), GFP_KERNEL);
+ if (!ssc) {
+ dev_dbg(&pdev->dev, "out of memory\n");
+ return -ENOMEM;
+ }
+
+ ssc->pdev = pdev;
+
+ plat_dat = atmel_ssc_get_driver_data(pdev);
+ if (!plat_dat)
+ return -ENODEV;
+ ssc->pdata = (struct atmel_ssc_platform_data *)plat_dat;
+
+ if (pdev->dev.of_node) {
+ struct device_node *np = pdev->dev.of_node;
+ ssc->clk_from_rk_pin =
+ of_property_read_bool(np, "atmel,clk-from-rk-pin");
+ }
+
+ regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ssc->regs = devm_ioremap_resource(&pdev->dev, regs);
+ if (IS_ERR(ssc->regs))
+ return PTR_ERR(ssc->regs);
+
+ ssc->phybase = regs->start;
+
+ ssc->clk = devm_clk_get(&pdev->dev, "pclk");
+ if (IS_ERR(ssc->clk)) {
+ dev_dbg(&pdev->dev, "no pclk clock defined\n");
+ return -ENXIO;
+ }
+
+ /* disable all interrupts */
+ clk_prepare_enable(ssc->clk);
+ ssc_writel(ssc->regs, IDR, -1);
+ ssc_readl(ssc->regs, SR);
+ clk_disable_unprepare(ssc->clk);
+
+ ssc->irq = platform_get_irq(pdev, 0);
+ if (!ssc->irq) {
+ dev_dbg(&pdev->dev, "could not get irq\n");
+ return -ENXIO;
+ }
+
+ spin_lock(&user_lock);
+ list_add_tail(&ssc->list, &ssc_list);
+ spin_unlock(&user_lock);
+
+ platform_set_drvdata(pdev, ssc);
+
+ dev_info(&pdev->dev, "Atmel SSC device at 0x%p (irq %d)\n",
+ ssc->regs, ssc->irq);
+
+ return 0;
+}
+
+static int ssc_remove(struct platform_device *pdev)
+{
+ struct ssc_device *ssc = platform_get_drvdata(pdev);
+
+ spin_lock(&user_lock);
+ list_del(&ssc->list);
+ spin_unlock(&user_lock);
+
+ return 0;
+}
+
+static struct platform_driver ssc_driver = {
+ .driver = {
+ .name = "ssc",
+ .of_match_table = of_match_ptr(atmel_ssc_dt_ids),
+ },
+ .id_table = atmel_ssc_devtypes,
+ .probe = ssc_probe,
+ .remove = ssc_remove,
+};
+module_platform_driver(ssc_driver);
+
+MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
+MODULE_DESCRIPTION("SSC driver for Atmel AVR32 and AT91");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ssc");
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