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path: root/drivers/pwm/pwm-tipwmss.c
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Diffstat (limited to 'drivers/pwm/pwm-tipwmss.c')
-rw-r--r--drivers/pwm/pwm-tipwmss.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-tipwmss.c b/drivers/pwm/pwm-tipwmss.c
new file mode 100644
index 000000000000..3448a1c88590
--- /dev/null
+++ b/drivers/pwm/pwm-tipwmss.c
@@ -0,0 +1,139 @@
+/*
+ * TI PWM Subsystem driver
+ *
+ * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/pm_runtime.h>
+#include <linux/of_device.h>
+
+#include "pwm-tipwmss.h"
+
+#define PWMSS_CLKCONFIG 0x8 /* Clock gating reg */
+#define PWMSS_CLKSTATUS 0xc /* Clock gating status reg */
+
+struct pwmss_info {
+ void __iomem *mmio_base;
+ struct mutex pwmss_lock;
+ u16 pwmss_clkconfig;
+};
+
+u16 pwmss_submodule_state_change(struct device *dev, int set)
+{
+ struct pwmss_info *info = dev_get_drvdata(dev);
+ u16 val;
+
+ mutex_lock(&info->pwmss_lock);
+ val = readw(info->mmio_base + PWMSS_CLKCONFIG);
+ val |= set;
+ writew(val , info->mmio_base + PWMSS_CLKCONFIG);
+ mutex_unlock(&info->pwmss_lock);
+
+ return readw(info->mmio_base + PWMSS_CLKSTATUS);
+}
+EXPORT_SYMBOL(pwmss_submodule_state_change);
+
+static const struct of_device_id pwmss_of_match[] = {
+ { .compatible = "ti,am33xx-pwmss" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, pwmss_of_match);
+
+static int pwmss_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct resource *r;
+ struct pwmss_info *info;
+ struct device_node *node = pdev->dev.of_node;
+
+ info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ dev_err(&pdev->dev, "failed to allocate memory\n");
+ return -ENOMEM;
+ }
+
+ mutex_init(&info->pwmss_lock);
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!r) {
+ dev_err(&pdev->dev, "no memory resource defined\n");
+ return -ENODEV;
+ }
+
+ info->mmio_base = devm_request_and_ioremap(&pdev->dev, r);
+ if (!info->mmio_base)
+ return -EADDRNOTAVAIL;
+
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_get_sync(&pdev->dev);
+ platform_set_drvdata(pdev, info);
+
+ /* Populate all the child nodes here... */
+ ret = of_platform_populate(node, NULL, NULL, &pdev->dev);
+ if (ret)
+ dev_err(&pdev->dev, "no child node found\n");
+
+ return ret;
+}
+
+static int pwmss_remove(struct platform_device *pdev)
+{
+ struct pwmss_info *info = platform_get_drvdata(pdev);
+
+ pm_runtime_put_sync(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+ mutex_destroy(&info->pwmss_lock);
+ return 0;
+}
+
+static int pwmss_suspend(struct device *dev)
+{
+ struct pwmss_info *info = dev_get_drvdata(dev);
+
+ info->pwmss_clkconfig = readw(info->mmio_base + PWMSS_CLKCONFIG);
+ pm_runtime_put_sync(dev);
+ return 0;
+}
+
+static int pwmss_resume(struct device *dev)
+{
+ struct pwmss_info *info = dev_get_drvdata(dev);
+
+ pm_runtime_get_sync(dev);
+ writew(info->pwmss_clkconfig, info->mmio_base + PWMSS_CLKCONFIG);
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(pwmss_pm_ops, pwmss_suspend, pwmss_resume);
+
+static struct platform_driver pwmss_driver = {
+ .driver = {
+ .name = "pwmss",
+ .owner = THIS_MODULE,
+ .pm = &pwmss_pm_ops,
+ .of_match_table = pwmss_of_match,
+ },
+ .probe = pwmss_probe,
+ .remove = pwmss_remove,
+};
+
+module_platform_driver(pwmss_driver);
+
+MODULE_DESCRIPTION("PWM Subsystem driver");
+MODULE_AUTHOR("Texas Instruments");
+MODULE_LICENSE("GPL");