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

Lee Jones
2015-05-13T14:37:25Z

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 <abrestic@chromium.org>
> Cc: Samuel Ortiz <sameo@linux.intel.com>
> Cc: Lee Jones <lee.jones@linaro.org>
> ---
> 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 <abrestic@chromium.org>");
> +MODULE_LICENSE("GPL v2");

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