[PATCH v2 1/4] reset: add driver for socfpga
Dinh Nguyen
dinguyen at altera.com
Tue Apr 15 15:22:47 PDT 2014
On Tue, 2014-04-15 at 09:20 +0200, Philipp Zabel wrote:
> Hi Dinh,
>
> Am Donnerstag, den 10.04.2014, 10:21 +0200 schrieb Steffen Trumtrar:
> > Add a reset-controller driver for the socfpga platform.
> > The reset-controller has four banks with up to 32 entries all encapsulated in
> > one module block.
> >
> > Signed-off-by: Steffen Trumtrar <s.trumtrar at pengutronix.de>
>
> in case you want to take this through your branch,
>
> Acked-by: Philipp Zabel <p.zabel at pengutronix.de>
>
> If you want me to take the reset controller driver, please let me know.
>
Yes, I will.
Thanks,
Dinh
> regards
> Philipp
>
> > ---
> > Changes since v1:
> > - use BITS_PER_LONG everywhere instead of MAX_BANK_WIDTH
> > - print pdev->dev.of_node->full_name on error
> > - use proper IS_ERR/PTR_ERR
> >
> > drivers/reset/Makefile | 1 +
> > drivers/reset/reset-socfpga.c | 147 ++++++++++++++++++++++++++++++++++++++++++
> > 2 files changed, 148 insertions(+)
> > create mode 100644 drivers/reset/reset-socfpga.c
> >
> > diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
> > index cc29832..ab64077 100644
> > --- a/drivers/reset/Makefile
> > +++ b/drivers/reset/Makefile
> > @@ -1,2 +1,3 @@
> > obj-$(CONFIG_RESET_CONTROLLER) += core.o
> > obj-$(CONFIG_ARCH_SUNXI) += reset-sunxi.o
> > +obj-$(CONFIG_ARCH_SOCFPGA) += reset-socfpga.o
> > diff --git a/drivers/reset/reset-socfpga.c b/drivers/reset/reset-socfpga.c
> > new file mode 100644
> > index 0000000..bdcd2fa
> > --- /dev/null
> > +++ b/drivers/reset/reset-socfpga.c
> > @@ -0,0 +1,147 @@
> > +/*
> > + * Copyright 2014 Steffen Trumtrar <s.trumtrar at pengutronix.de>
> > + *
> > + * based on
> > + * Allwinner SoCs Reset Controller driver
> > + *
> > + * Copyright 2013 Maxime Ripard
> > + *
> > + * Maxime Ripard <maxime.ripard at free-electrons.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.
> > + */
> > +
> > +#include <linux/err.h>
> > +#include <linux/io.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/reset-controller.h>
> > +#include <linux/spinlock.h>
> > +#include <linux/types.h>
> > +
> > +#define NR_BANKS 4
> > +#define OFFSET_MODRST 0x10
> > +
> > +struct socfpga_reset_data {
> > + spinlock_t lock;
> > + void __iomem *membase;
> > + struct reset_controller_dev rcdev;
> > +};
> > +
> > +static int socfpga_reset_assert(struct reset_controller_dev *rcdev,
> > + unsigned long id)
> > +{
> > + struct socfpga_reset_data *data = container_of(rcdev,
> > + struct socfpga_reset_data,
> > + rcdev);
> > + int bank = id / BITS_PER_LONG;
> > + int offset = id % BITS_PER_LONG;
> > + unsigned long flags;
> > + u32 reg;
> > +
> > + spin_lock_irqsave(&data->lock, flags);
> > +
> > + reg = readl(data->membase + OFFSET_MODRST + (bank * NR_BANKS));
> > + writel(reg | BIT(offset), data->membase + OFFSET_MODRST +
> > + (bank * NR_BANKS));
> > + spin_unlock_irqrestore(&data->lock, flags);
> > +
> > + return 0;
> > +}
> > +
> > +static int socfpga_reset_deassert(struct reset_controller_dev *rcdev,
> > + unsigned long id)
> > +{
> > + struct socfpga_reset_data *data = container_of(rcdev,
> > + struct socfpga_reset_data,
> > + rcdev);
> > +
> > + int bank = id / BITS_PER_LONG;
> > + int offset = id % BITS_PER_LONG;
> > + unsigned long flags;
> > + u32 reg;
> > +
> > + spin_lock_irqsave(&data->lock, flags);
> > +
> > + reg = readl(data->membase + OFFSET_MODRST + (bank * NR_BANKS));
> > + writel(reg & ~BIT(offset), data->membase + OFFSET_MODRST +
> > + (bank * NR_BANKS));
> > +
> > + spin_unlock_irqrestore(&data->lock, flags);
> > +
> > + return 0;
> > +}
> > +
> > +static struct reset_control_ops socfpga_reset_ops = {
> > + .assert = socfpga_reset_assert,
> > + .deassert = socfpga_reset_deassert,
> > +};
> > +
> > +static int socfpga_reset_probe(struct platform_device *pdev)
> > +{
> > + struct socfpga_reset_data *data;
> > + struct resource *res;
> > + int ret;
> > +
> > + /*
> > + * The binding was mainlined without the required property.
> > + * Do not continue, when we encounter an old DT.
> > + */
> > + if (!of_find_property(pdev->dev.of_node, "#reset-cells", NULL)) {
> > + dev_err(&pdev->dev, "%s missing #reset-cells property\n",
> > + pdev->dev.of_node->full_name);
> > + return -EINVAL;
> > + }
> > +
> > + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
> > + if (!data)
> > + return -ENOMEM;
> > +
> > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > + data->membase = devm_ioremap_resource(&pdev->dev, res);
> > + if (IS_ERR(data->membase))
> > + return PTR_ERR(data->membase);
> > +
> > + spin_lock_init(&data->lock);
> > +
> > + data->rcdev.owner = THIS_MODULE;
> > + data->rcdev.nr_resets = NR_BANKS * BITS_PER_LONG;
> > + data->rcdev.ops = &socfpga_reset_ops;
> > + data->rcdev.of_node = pdev->dev.of_node;
> > + reset_controller_register(&data->rcdev);
> > +
> > + return 0;
> > +}
> > +
> > +static int socfpga_reset_remove(struct platform_device *pdev)
> > +{
> > + struct socfpga_reset_data *data = platform_get_drvdata(pdev);
> > +
> > + reset_controller_unregister(&data->rcdev);
> > +
> > + return 0;
> > +}
> > +
> > +static const struct of_device_id socfpga_reset_dt_ids[] = {
> > + { .compatible = "altr,rst-mgr", },
> > + { /* sentinel */ },
> > +};
> > +
> > +static struct platform_driver socfpga_reset_driver = {
> > + .probe = socfpga_reset_probe,
> > + .remove = socfpga_reset_remove,
> > + .driver = {
> > + .name = "socfpga-reset",
> > + .owner = THIS_MODULE,
> > + .of_match_table = socfpga_reset_dt_ids,
> > + },
> > +};
> > +module_platform_driver(socfpga_reset_driver);
> > +
> > +MODULE_AUTHOR("Steffen Trumtrar <s.trumtrar at pengutronix.de");
> > +MODULE_DESCRIPTION("Socfpga Reset Controller Driver");
> > +MODULE_LICENSE("GPL");
>
>
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