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Based on 1 normalized pattern(s): 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 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 you should have received a copy of the gnu general public license along with this program if not see http www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 503 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Enrico Weigelt <info@metux.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
126 lines
3.1 KiB
C
126 lines
3.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Driver for Atmel Flexcom
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*
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* Copyright (C) 2015 Atmel Corporation
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*
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* Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
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*/
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/platform_device.h>
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#include <linux/of.h>
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#include <linux/of_platform.h>
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#include <linux/err.h>
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#include <linux/io.h>
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#include <linux/clk.h>
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#include <dt-bindings/mfd/atmel-flexcom.h>
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/* I/O register offsets */
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#define FLEX_MR 0x0 /* Mode Register */
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#define FLEX_VERSION 0xfc /* Version Register */
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/* Mode Register bit fields */
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#define FLEX_MR_OPMODE_OFFSET (0) /* Operating Mode */
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#define FLEX_MR_OPMODE_MASK (0x3 << FLEX_MR_OPMODE_OFFSET)
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#define FLEX_MR_OPMODE(opmode) (((opmode) << FLEX_MR_OPMODE_OFFSET) & \
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FLEX_MR_OPMODE_MASK)
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struct atmel_flexcom {
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void __iomem *base;
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u32 opmode;
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struct clk *clk;
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};
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static int atmel_flexcom_probe(struct platform_device *pdev)
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{
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struct device_node *np = pdev->dev.of_node;
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struct resource *res;
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struct atmel_flexcom *ddata;
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int err;
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ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL);
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if (!ddata)
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return -ENOMEM;
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platform_set_drvdata(pdev, ddata);
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err = of_property_read_u32(np, "atmel,flexcom-mode", &ddata->opmode);
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if (err)
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return err;
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if (ddata->opmode < ATMEL_FLEXCOM_MODE_USART ||
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ddata->opmode > ATMEL_FLEXCOM_MODE_TWI)
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return -EINVAL;
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res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
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ddata->base = devm_ioremap_resource(&pdev->dev, res);
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if (IS_ERR(ddata->base))
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return PTR_ERR(ddata->base);
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ddata->clk = devm_clk_get(&pdev->dev, NULL);
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if (IS_ERR(ddata->clk))
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return PTR_ERR(ddata->clk);
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err = clk_prepare_enable(ddata->clk);
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if (err)
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return err;
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/*
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* Set the Operating Mode in the Mode Register: only the selected device
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* is clocked. Hence, registers of the other serial devices remain
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* inaccessible and are read as zero. Also the external I/O lines of the
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* Flexcom are muxed to reach the selected device.
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*/
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writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base + FLEX_MR);
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clk_disable_unprepare(ddata->clk);
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return devm_of_platform_populate(&pdev->dev);
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}
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static const struct of_device_id atmel_flexcom_of_match[] = {
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{ .compatible = "atmel,sama5d2-flexcom" },
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{ /* sentinel */ }
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};
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MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match);
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#ifdef CONFIG_PM_SLEEP
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static int atmel_flexcom_resume(struct device *dev)
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{
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struct atmel_flexcom *ddata = dev_get_drvdata(dev);
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int err;
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u32 val;
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err = clk_prepare_enable(ddata->clk);
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if (err)
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return err;
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val = FLEX_MR_OPMODE(ddata->opmode),
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writel(val, ddata->base + FLEX_MR);
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clk_disable_unprepare(ddata->clk);
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return 0;
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}
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#endif
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static SIMPLE_DEV_PM_OPS(atmel_flexcom_pm_ops, NULL,
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atmel_flexcom_resume);
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static struct platform_driver atmel_flexcom_driver = {
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.probe = atmel_flexcom_probe,
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.driver = {
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.name = "atmel_flexcom",
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.pm = &atmel_flexcom_pm_ops,
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.of_match_table = atmel_flexcom_of_match,
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},
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};
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module_platform_driver(atmel_flexcom_driver);
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MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>");
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MODULE_DESCRIPTION("Atmel Flexcom MFD driver");
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MODULE_LICENSE("GPL v2");
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