diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/mfd/atmel-flexcom.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mfd/atmel-flexcom.c')
-rw-r--r-- | drivers/mfd/atmel-flexcom.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/drivers/mfd/atmel-flexcom.c b/drivers/mfd/atmel-flexcom.c new file mode 100644 index 0000000000..b52f7ffdad --- /dev/null +++ b/drivers/mfd/atmel-flexcom.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for Atmel Flexcom + * + * Copyright (C) 2015 Atmel Corporation + * + * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com> + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/clk.h> +#include <dt-bindings/mfd/atmel-flexcom.h> + +/* I/O register offsets */ +#define FLEX_MR 0x0 /* Mode Register */ +#define FLEX_VERSION 0xfc /* Version Register */ + +/* Mode Register bit fields */ +#define FLEX_MR_OPMODE_OFFSET (0) /* Operating Mode */ +#define FLEX_MR_OPMODE_MASK (0x3 << FLEX_MR_OPMODE_OFFSET) +#define FLEX_MR_OPMODE(opmode) (((opmode) << FLEX_MR_OPMODE_OFFSET) & \ + FLEX_MR_OPMODE_MASK) + +struct atmel_flexcom { + void __iomem *base; + u32 opmode; + struct clk *clk; +}; + +static int atmel_flexcom_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct atmel_flexcom *ddata; + int err; + + ddata = devm_kzalloc(&pdev->dev, sizeof(*ddata), GFP_KERNEL); + if (!ddata) + return -ENOMEM; + + platform_set_drvdata(pdev, ddata); + + err = of_property_read_u32(np, "atmel,flexcom-mode", &ddata->opmode); + if (err) + return err; + + if (ddata->opmode < ATMEL_FLEXCOM_MODE_USART || + ddata->opmode > ATMEL_FLEXCOM_MODE_TWI) + return -EINVAL; + + ddata->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL); + if (IS_ERR(ddata->base)) + return PTR_ERR(ddata->base); + + ddata->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(ddata->clk)) + return PTR_ERR(ddata->clk); + + err = clk_prepare_enable(ddata->clk); + if (err) + return err; + + /* + * Set the Operating Mode in the Mode Register: only the selected device + * is clocked. Hence, registers of the other serial devices remain + * inaccessible and are read as zero. Also the external I/O lines of the + * Flexcom are muxed to reach the selected device. + */ + writel(FLEX_MR_OPMODE(ddata->opmode), ddata->base + FLEX_MR); + + clk_disable_unprepare(ddata->clk); + + return devm_of_platform_populate(&pdev->dev); +} + +static const struct of_device_id atmel_flexcom_of_match[] = { + { .compatible = "atmel,sama5d2-flexcom" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, atmel_flexcom_of_match); + +static int __maybe_unused atmel_flexcom_resume_noirq(struct device *dev) +{ + struct atmel_flexcom *ddata = dev_get_drvdata(dev); + int err; + u32 val; + + err = clk_prepare_enable(ddata->clk); + if (err) + return err; + + val = FLEX_MR_OPMODE(ddata->opmode), + writel(val, ddata->base + FLEX_MR); + + clk_disable_unprepare(ddata->clk); + + return 0; +} + +static const struct dev_pm_ops __maybe_unused atmel_flexcom_pm_ops = { + .resume_noirq = atmel_flexcom_resume_noirq, +}; + +static struct platform_driver atmel_flexcom_driver = { + .probe = atmel_flexcom_probe, + .driver = { + .name = "atmel_flexcom", + .pm = pm_ptr(&atmel_flexcom_pm_ops), + .of_match_table = atmel_flexcom_of_match, + }, +}; + +module_platform_driver(atmel_flexcom_driver); + +MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>"); +MODULE_DESCRIPTION("Atmel Flexcom MFD driver"); +MODULE_LICENSE("GPL v2"); |