Subject: [PATCH v8 5/9] mfd: Add driver for NVIDIA Tegra XUSB

From: [email-masked] (Lee Jones)
Date: Wed, 13 May 2015 15:37:15 +0100

On Mon, 04 May 2015, Andrew Bresticker wrote:

> Add an MFD driver for the XUSB host complex found on NVIDIA Tegra124
> and later SoCs.

What else does it do besides USB?

> Signed-off-by: Andrew Bresticker <[email-masked]>
> Cc: Samuel Ortiz <[email-masked]>
> Cc: Lee Jones <[email-masked]>
> ---
> Changes from v7:
>  - Have child nodes get non-shared memory and interrupts from DT.
>  - Use of_platform_populate rather than mfd_add_devices.
>  - Get rid of struct tegra_xusb.
> New for v7.
> ---
>  drivers/mfd/Kconfig      |  7 +++++
>  drivers/mfd/Makefile     |  1 +
>  drivers/mfd/tegra-xusb.c | 75 ++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 83 insertions(+)
>  create mode 100644 drivers/mfd/tegra-xusb.c
> 
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index d5ad04d..61872b4 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -1430,6 +1430,13 @@ config MFD_STW481X
>  	  in various ST Microelectronics and ST-Ericsson embedded
>  	  Nomadik series.
>  
> +config MFD_TEGRA_XUSB
> +	tristate "NVIDIA Tegra XUSB"
> +	depends on ARCH_TEGRA
> +	select MFD_CORE
> +	help
> +	  Support for the XUSB complex found on NVIDIA Tegra124 and later SoCs.
> +
>  menu "Multimedia Capabilities Port drivers"
>  	depends on ARCH_SA1100
>  
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 0e5cfeb..7588caf 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -181,6 +181,7 @@ obj-$(CONFIG_MFD_HI6421_PMIC)	+= hi6421-pmic-core.o
>  obj-$(CONFIG_MFD_DLN2)		+= dln2.o
>  obj-$(CONFIG_MFD_RT5033)	+= rt5033.o
>  obj-$(CONFIG_MFD_SKY81452)	+= sky81452.o
> +obj-$(CONFIG_MFD_TEGRA_XUSB)	+= tegra-xusb.o
>  
>  intel-soc-pmic-objs		:= intel_soc_pmic_core.o intel_soc_pmic_crc.o
>  obj-$(CONFIG_INTEL_SOC_PMIC)	+= intel-soc-pmic.o
> diff --git a/drivers/mfd/tegra-xusb.c b/drivers/mfd/tegra-xusb.c
> new file mode 100644
> index 0000000..e11fa23
> --- /dev/null
> +++ b/drivers/mfd/tegra-xusb.c
> @@ -0,0 +1,75 @@
> +/*
> + * NVIDIA Tegra XUSB MFD driver
> + *
> + * Copyright (C) 2015 Google, Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms and conditions of the GNU General Public License,
> + * version 2, as published by the Free Software Foundation.
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/mfd/core.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +
> +static const struct of_device_id tegra_xusb_of_match[] = {
> +	{ .compatible = "nvidia,tegra124-xusb", },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, tegra_xusb_of_match);

If you're not using this to patch on, I'd prefer you place it next to
where it's first used i.e. down at the bottom of the file.

> +static struct regmap_config tegra_fpci_regmap_config = {
> +	.reg_bits = 32,
> +	.val_bits = 32,
> +	.reg_stride = 4,
> +};
> +
> +static int tegra_xusb_probe(struct platform_device *pdev)
> +{
> +	struct resource *res;
> +	struct regmap *fpci_regs;
> +	void __iomem *fpci_base;
> +	int ret;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	fpci_base = devm_ioremap_resource(&pdev->dev, res);
> +	if (IS_ERR(fpci_base))
> +		return PTR_ERR(fpci_base);
> +
> +	tegra_fpci_regmap_config.max_register = res->end - res->start - 3;
> +	fpci_regs = devm_regmap_init_mmio(&pdev->dev, fpci_base,
> +					  &tegra_fpci_regmap_config);
> +	if (IS_ERR(fpci_regs)) {
> +		ret = PTR_ERR(fpci_regs);
> +		dev_err(&pdev->dev, "Failed to init regmap: %d\n", ret);
> +		return ret;
> +	}
> +	platform_set_drvdata(pdev, fpci_regs);
> +
> +	ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "Failed to add sub-devices: %d\n", ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static struct platform_driver tegra_xusb_driver = {
> +	.probe = tegra_xusb_probe,

No .remove()?

> +	.driver = {
> +		.name = "tegra-xusb",
> +		.of_match_table = tegra_xusb_of_match,
> +	},
> +};
> +module_platform_driver(tegra_xusb_driver);
> +
> +MODULE_DESCRIPTION("NVIDIA Tegra XUSB MFD");
> +MODULE_AUTHOR("Andrew Bresticker <[email-masked]>");
> +MODULE_LICENSE("GPL v2");

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org ? Open source software for ARM SoCs
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