diff options
Diffstat (limited to 'drivers/pwm/pwm-tipwmss.c')
| -rw-r--r-- | drivers/pwm/pwm-tipwmss.c | 139 |
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 00000000000..3448a1c8859 --- /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"); |