diff options
| -rw-r--r-- | drivers/clk/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/clk/Makefile | 1 | ||||
| -rw-r--r-- | drivers/clk/clk-fixed-mmio.c | 101 |
3 files changed, 108 insertions, 0 deletions
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index e5b2fe80eab4..296972518db4 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -290,6 +290,12 @@ config COMMON_CLK_BD718XX This driver supports ROHM BD71837 and ROHM BD71847 PMICs clock gates. +config COMMON_CLK_FIXED_MMIO + bool "Clock driver for Memory Mapped Fixed values" + depends on COMMON_CLK && OF + help + Support for Memory Mapped IO Fixed clocks + source "drivers/clk/actions/Kconfig" source "drivers/clk/bcm/Kconfig" source "drivers/clk/hisilicon/Kconfig" diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index 8a9440a97500..d6cd32bda771 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_COMMON_CLK_CDCE925) += clk-cdce925.o obj-$(CONFIG_ARCH_CLPS711X) += clk-clps711x.o obj-$(CONFIG_COMMON_CLK_CS2000_CP) += clk-cs2000-cp.o obj-$(CONFIG_ARCH_EFM32) += clk-efm32gg.o +obj-$(CONFIG_COMMON_CLK_FIXED_MMIO) += clk-fixed-mmio.o obj-$(CONFIG_COMMON_CLK_GEMINI) += clk-gemini.o obj-$(CONFIG_COMMON_CLK_ASPEED) += clk-aspeed.o obj-$(CONFIG_ARCH_HIGHBANK) += clk-highbank.o diff --git a/drivers/clk/clk-fixed-mmio.c b/drivers/clk/clk-fixed-mmio.c new file mode 100644 index 000000000000..d1a97d971183 --- /dev/null +++ b/drivers/clk/clk-fixed-mmio.c @@ -0,0 +1,101 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Memory Mapped IO Fixed clock driver + * + * Copyright (C) 2018 Cadence Design Systems, Inc. + * + * Authors: + * Jan Kotas <jank@cadence.com> + */ + +#include <linux/clk-provider.h> +#include <linux/of_address.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +static struct clk_hw *fixed_mmio_clk_setup(struct device_node *node) +{ + struct clk_hw *clk; + const char *clk_name = node->name; + void __iomem *base; + u32 freq; + int ret; + + base = of_iomap(node, 0); + if (!base) { + pr_err("%pOFn: failed to map address\n", node); + return ERR_PTR(-EIO); + } + + freq = readl(base); + iounmap(base); + of_property_read_string(node, "clock-output-names", &clk_name); + + clk = clk_hw_register_fixed_rate(NULL, clk_name, NULL, 0, freq); + if (IS_ERR(clk)) { + pr_err("%pOFn: failed to register fixed rate clock\n", node); + return clk; + } + + ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, clk); + if (ret) { + pr_err("%pOFn: failed to add clock provider\n", node); + clk_hw_unregister(clk); + clk = ERR_PTR(ret); + } + + return clk; +} + +static void __init of_fixed_mmio_clk_setup(struct device_node *node) +{ + fixed_mmio_clk_setup(node); +} +CLK_OF_DECLARE(fixed_mmio_clk, "fixed-mmio-clock", of_fixed_mmio_clk_setup); + +/** + * This is not executed when of_fixed_mmio_clk_setup succeeded. + */ +static int of_fixed_mmio_clk_probe(struct platform_device *pdev) +{ + struct clk_hw *clk; + + clk = fixed_mmio_clk_setup(pdev->dev.of_node); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + platform_set_drvdata(pdev, clk); + + return 0; +} + +static int of_fixed_mmio_clk_remove(struct platform_device *pdev) +{ + struct clk_hw *clk = platform_get_drvdata(pdev); + + of_clk_del_provider(pdev->dev.of_node); + clk_hw_unregister_fixed_rate(clk); + + return 0; +} + +static const struct of_device_id of_fixed_mmio_clk_ids[] = { + { .compatible = "fixed-mmio-clock" }, + { } +}; +MODULE_DEVICE_TABLE(of, of_fixed_mmio_clk_ids); + +static struct platform_driver of_fixed_mmio_clk_driver = { + .driver = { + .name = "of_fixed_mmio_clk", + .of_match_table = of_fixed_mmio_clk_ids, + }, + .probe = of_fixed_mmio_clk_probe, + .remove = of_fixed_mmio_clk_remove, +}; +module_platform_driver(of_fixed_mmio_clk_driver); + +MODULE_AUTHOR("Jan Kotas <jank@cadence.com>"); +MODULE_DESCRIPTION("Memory Mapped IO Fixed clock driver"); +MODULE_LICENSE("GPL v2"); |