Support BD71837 gateable 32768 Hz clock. Signed-off-by: Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx> --- drivers/clk/Kconfig | 6 ++ drivers/clk/Makefile | 1 + drivers/clk/clk-bd71837.c | 145 ++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 152 insertions(+) create mode 100644 drivers/clk/clk-bd71837.c diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 41492e980ef4..065421a9eb22 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -279,6 +279,12 @@ config COMMON_CLK_STM32H7 ---help--- Support for stm32h7 SoC family clocks +config COMMON_CLK_BD71837 + tristate "Clock driver for ROHM BD71837 PMIC MFD" + depends on MFD_BD71837 + help + This driver supports ROHM BD71837 PMIC clock. + source "drivers/clk/bcm/Kconfig" source "drivers/clk/hisilicon/Kconfig" source "drivers/clk/imgtec/Kconfig" diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index de6d06ac790b..8393c4af7d5a 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -21,6 +21,7 @@ endif obj-$(CONFIG_MACH_ASM9260) += clk-asm9260.o obj-$(CONFIG_COMMON_CLK_AXI_CLKGEN) += clk-axi-clkgen.o obj-$(CONFIG_ARCH_AXXIA) += clk-axm5516.o +obj-$(CONFIG_COMMON_CLK_BD71837) += clk-bd71837.o obj-$(CONFIG_COMMON_CLK_CDCE706) += clk-cdce706.o obj-$(CONFIG_COMMON_CLK_CDCE925) += clk-cdce925.o obj-$(CONFIG_ARCH_CLPS711X) += clk-clps711x.o diff --git a/drivers/clk/clk-bd71837.c b/drivers/clk/clk-bd71837.c new file mode 100644 index 000000000000..8b9aae33eade --- /dev/null +++ b/drivers/clk/clk-bd71837.c @@ -0,0 +1,145 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 ROHM Semiconductors +// bd71837.c -- ROHM BD71837MWV clock driver + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/err.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/mfd/bd71837.h> +#include <linux/clk-provider.h> + +struct bd71837_clk { + struct clk_hw hw; + u8 reg; + u8 mask; + unsigned long rate; + struct platform_device *pdev; + struct bd71837 *mfd; +}; + +static int bd71837_clk_set(struct clk_hw *hw, int status) +{ + struct bd71837_clk *c = container_of(hw, struct bd71837_clk, hw); + + return bd71837_update_bits(c->mfd, c->reg, c->mask, status); +} + +static void bd71837_clk_disable(struct clk_hw *hw) +{ + int rv; + struct bd71837_clk *c = container_of(hw, struct bd71837_clk, hw); + + rv = bd71837_clk_set(hw, 0); + if (rv) + dev_dbg(&c->pdev->dev, "Failed to disable 32K clk (%d)\n", rv); +} + +static int bd71837_clk_enable(struct clk_hw *hw) +{ + return bd71837_clk_set(hw, 1); +} + +static int bd71837_clk_is_enabled(struct clk_hw *hw) +{ + int enabled; + struct bd71837_clk *c = container_of(hw, struct bd71837_clk, hw); + + enabled = c->mask; + enabled &= bd71837_reg_read(c->mfd, c->reg); + + return enabled; +} +static unsigned long bd71837_clk_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct bd71837_clk *c = container_of(hw, struct bd71837_clk, hw); + + return c->rate; +} + +static struct clk_ops bd71837_clk_ops = { + .prepare = &bd71837_clk_enable, + .unprepare = &bd71837_clk_disable, + .is_prepared = &bd71837_clk_is_enabled, +}; + +static int bd71837_clk_probe(struct platform_device *pdev) +{ + struct bd71837_clk *c; + int rval = -ENOMEM; + const char *parent_clk; + struct device *parent = pdev->dev.parent; + struct bd71837 *mfd = dev_get_drvdata(parent); + struct clk_init_data init = { + .name = "bd71837-32k-out", + .ops = &bd71837_clk_ops, + }; + + c = devm_kzalloc(&pdev->dev, sizeof(*c), GFP_KERNEL); + return -ENOMEM; + + parent_clk = of_clk_get_parent_name(parent->of_node, 0); + + init.parent_names = &parent_clk; + if (parent_clk) { + init.num_parents = 1; + } else { + /* If parent is not given from DT we assume the typical + * use-case with 32.768 KHz oscillator for RTC (Maybe we + * should just error out here and require parent?) + */ + c->rate = BD71837_CLK_RATE; + bd71837_clk_ops.recalc_rate = &bd71837_clk_recalc_rate; + dev_warn(&pdev->dev, "No parent clk found - assuming 32,768 KHz\n"); + } + + c->reg = BD71837_REG_OUT32K; + c->mask = BD71837_OUT32K_EN; + c->mfd = mfd; + c->pdev = pdev; + c->hw.init = &init; + + of_property_read_string_index(parent->of_node, + "clock-output-names", 0, + &init.name); + + rval = devm_clk_hw_register(&pdev->dev, &c->hw); + if (!rval) { + if (parent->of_node) { + rval = of_clk_add_hw_provider(parent->of_node, + of_clk_hw_simple_get, + &c->hw); + if (rval) + dev_err(&pdev->dev, + "adding clk provider failed\n"); + } + } else { + dev_err(&pdev->dev, "failed to register 32K clk"); + } + + return rval; +} + +static int bd71837_clk_remove(struct platform_device *pdev) +{ + if (pdev->dev.parent->of_node) + of_clk_del_provider(pdev->dev.parent->of_node); + return 0; +} + +static struct platform_driver bd71837_clk = { + .driver = { + .name = "bd71837-clk", + }, + .probe = bd71837_clk_probe, + .remove = bd71837_clk_remove, +}; + +module_platform_driver(bd71837_clk); + +MODULE_AUTHOR("Matti Vaittinen <matti.vaittinen@xxxxxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("BD71837 chip clk driver"); +MODULE_LICENSE("GPL"); -- 2.14.3 -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html