3 files changed, 187 insertions, 0 deletions

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 73e248fb2ff1..346c44eff95e 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -203,4 +203,16 @@ config THINKPAD_ACPI_BAY
           If you are not sure, say Y here.
 
 
+config ATMEL_SSC
+        tristate "Device driver for Atmel SSC peripheral"
+        depends on AVR32 || ARCH_AT91
+        ---help---
+          This option enables device driver support for Atmel Syncronized
+          Serial Communication peripheral (SSC).
+
+          The SSC peripheral supports a wide variety of serial frame based
+          communications, i.e. I2S, SPI, etc.
+
+          If unsure, say N.
+
 endif # MISC_DEVICES
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index b5ce0e3dba86..a24c61475c2f 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_IBM_ASM)		+= ibmasm/
 obj-$(CONFIG_HDPU_FEATURES)     += hdpuftrs/
 obj-$(CONFIG_MSI_LAPTOP)     += msi-laptop.o
 obj-$(CONFIG_ASUS_LAPTOP)     += asus-laptop.o
+obj-$(CONFIG_ATMEL_SSC)         += atmel-ssc.o
 obj-$(CONFIG_LKDTM)             += lkdtm.o
 obj-$(CONFIG_TIFM_CORE)         += tifm_core.o
 obj-$(CONFIG_TIFM_7XX1)         += tifm_7xx1.o
diff --git a/drivers/misc/atmel-ssc.c b/drivers/misc/atmel-ssc.c
new file mode 100644
index 000000000000..058ccac700d0
--- /dev/null
+++ b/drivers/misc/atmel-ssc.c
@@ -0,0 +1,174 @@
+/*
+ * 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/list.h>
+#include <linux/spinlock.h>
+#include <linux/atmel-ssc.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->id == ssc_num) {
+                        ssc_valid = 1;
+                        break;
+                }
+        }
+
+        if (!ssc_valid) {
+                spin_unlock(&user_lock);
+                dev_dbg(&ssc->pdev->dev, "could not find requested device\n");
+                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_enable(ssc->clk);
+
+        return ssc;
+}
+EXPORT_SYMBOL(ssc_request);
+
+void ssc_free(struct ssc_device *ssc)
+{
+        spin_lock(&user_lock);
+        if (ssc->user) {
+                ssc->user--;
+                clk_disable(ssc->clk);
+        } else {
+                dev_dbg(&ssc->pdev->dev, "device already free\n");
+        }
+        spin_unlock(&user_lock);
+}
+EXPORT_SYMBOL(ssc_free);
+
+static int __init ssc_probe(struct platform_device *pdev)
+{
+        int retval = 0;
+        struct resource *regs;
+        struct ssc_device *ssc;
+
+        ssc = kzalloc(sizeof(struct ssc_device), GFP_KERNEL);
+        if (!ssc) {
+                dev_dbg(&pdev->dev, "out of memory\n");
+                retval = -ENOMEM;
+                goto out;
+        }
+
+        regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!regs) {
+                dev_dbg(&pdev->dev, "no mmio resource defined\n");
+                retval = -ENXIO;
+                goto out_free;
+        }
+
+        ssc->clk = clk_get(&pdev->dev, "pclk");
+        if (IS_ERR(ssc->clk)) {
+                dev_dbg(&pdev->dev, "no pclk clock defined\n");
+                retval = -ENXIO;
+                goto out_free;
+        }
+
+        ssc->pdev = pdev;
+        ssc->regs = ioremap(regs->start, regs->end - regs->start + 1);
+        if (!ssc->regs) {
+                dev_dbg(&pdev->dev, "ioremap failed\n");
+                retval = -EINVAL;
+                goto out_clk;
+        }
+
+        /* disable all interrupts */
+        clk_enable(ssc->clk);
+        ssc_writel(ssc->regs, IDR, ~0UL);
+        ssc_readl(ssc->regs, SR);
+        clk_disable(ssc->clk);
+
+        ssc->irq = platform_get_irq(pdev, 0);
+        if (!ssc->irq) {
+                dev_dbg(&pdev->dev, "could not get irq\n");
+                retval = -ENXIO;
+                goto out_unmap;
+        }
+
+        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);
+
+        goto out;
+
+out_unmap:
+        iounmap(ssc->regs);
+out_clk:
+        clk_put(ssc->clk);
+out_free:
+        kfree(ssc);
+out:
+        return retval;
+}
+
+static int __devexit ssc_remove(struct platform_device *pdev)
+{
+        struct ssc_device *ssc = platform_get_drvdata(pdev);
+
+        spin_lock(&user_lock);
+        iounmap(ssc->regs);
+        clk_put(ssc->clk);
+        list_del(&ssc->list);
+        kfree(ssc);
+        spin_unlock(&user_lock);
+
+        return 0;
+}
+
+static struct platform_driver ssc_driver = {
+        .remove         = __devexit_p(ssc_remove),
+        .driver         = {
+                .name           = "ssc",
+        },
+};
+
+static int __init ssc_init(void)
+{
+        return platform_driver_probe(&ssc_driver, ssc_probe);
+}
+module_init(ssc_init);
+
+static void __exit ssc_exit(void)
+{
+        platform_driver_unregister(&ssc_driver);
+}
+module_exit(ssc_exit);
+
+MODULE_AUTHOR("Hans-Christian Egtvedt <hcegtvedt@atmel.com>");
+MODULE_DESCRIPTION("SSC driver for Atmel AVR32 and AT91");
+MODULE_LICENSE("GPL");