RE: [RFC 04/11] clk: imx: Add gate shared for i.MX8MP audiomix

[Peng Fan]

> Subject: [RFC 04/11] clk: imx: Add gate shared for i.MX8MP audiomix
> 
> The newer i.MX platform use some gates that have a shared control bit
> between them.

Could the existing clk_hw_register_gate2 handle your case?

Thanks,
Peng.
> 
> Signed-off-by: Abel Vesa <abel.vesa@xxxxxxx>
> ---
>  drivers/clk/imx/Makefile          |   2 +-
>  drivers/clk/imx/clk-gate-shared.c | 111
> ++++++++++++++++++++++++++++++++++++++
>  drivers/clk/imx/clk.h             |   4 ++
>  3 files changed, 116 insertions(+), 1 deletion(-)  create mode 100644
> drivers/clk/imx/clk-gate-shared.c
> 
> diff --git a/drivers/clk/imx/Makefile b/drivers/clk/imx/Makefile index
> 928f874c..799a8ef 100644
> --- a/drivers/clk/imx/Makefile
> +++ b/drivers/clk/imx/Makefile
> @@ -27,7 +27,7 @@ obj-$(CONFIG_MXC_CLK_SCU) += \
> 
>  obj-$(CONFIG_CLK_IMX8MM) += clk-imx8mm.o
>  obj-$(CONFIG_CLK_IMX8MN) += clk-imx8mn.o
> -obj-$(CONFIG_CLK_IMX8MP) += clk-imx8mp.o
> +obj-$(CONFIG_CLK_IMX8MP) += clk-imx8mp.o clk-gate-shared.o
>  obj-$(CONFIG_CLK_IMX8MQ) += clk-imx8mq.o
>  obj-$(CONFIG_CLK_IMX8QXP) += clk-imx8qxp.o clk-imx8qxp-lpcg.o
> 
> diff --git a/drivers/clk/imx/clk-gate-shared.c
> b/drivers/clk/imx/clk-gate-shared.c
> new file mode 100644
> index 00000000..961a0e3
> --- /dev/null
> +++ b/drivers/clk/imx/clk-gate-shared.c
> @@ -0,0 +1,111 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2019 NXP.
> + */
> +
> +#include <linux/clk-provider.h>
> +#include <linux/err.h>
> +#include <linux/io.h>
> +#include <linux/slab.h>
> +#include "clk.h"
> +
> +/**
> + * struct clk_gate_shared - i.MX specific gate clock having the gate
> +flag
> + * shared with other gate clocks
> + */
> +struct clk_gate_shared {
> +	struct clk_gate	gate;
> +	spinlock_t	*lock;
> +	unsigned int	*share_count;
> +};
> +
> +static int clk_gate_shared_enable(struct clk_hw *hw) {
> +	struct clk_gate *gate = to_clk_gate(hw);
> +	struct clk_gate_shared *shgate = container_of(gate,
> +					struct clk_gate_shared, gate);
> +	unsigned long flags = 0;
> +	int ret = 0;
> +
> +	spin_lock_irqsave(shgate->lock, flags);
> +
> +	if (shgate->share_count && (*shgate->share_count)++ > 0)
> +		goto out;
> +
> +	ret = clk_gate_ops.enable(hw);
> +out:
> +	spin_unlock_irqrestore(shgate->lock, flags);
> +
> +	return ret;
> +}
> +
> +static void clk_gate_shared_disable(struct clk_hw *hw) {
> +	struct clk_gate *gate = to_clk_gate(hw);
> +	struct clk_gate_shared *shgate = container_of(gate,
> +					struct clk_gate_shared, gate);
> +	unsigned long flags = 0;
> +
> +	spin_lock_irqsave(shgate->lock, flags);
> +
> +	if (shgate->share_count) {
> +		if (WARN_ON(*shgate->share_count == 0))
> +			goto out;
> +		else if (--(*shgate->share_count) > 0)
> +			goto out;
> +	}
> +
> +	clk_gate_ops.disable(hw);
> +out:
> +	spin_unlock_irqrestore(shgate->lock, flags); }
> +
> +static int clk_gate_shared_is_enabled(struct clk_hw *hw) {
> +	return clk_gate_ops.is_enabled(hw);
> +}
> +
> +static const struct clk_ops clk_gate_shared_ops = {
> +	.enable = clk_gate_shared_enable,
> +	.disable = clk_gate_shared_disable,
> +	.is_enabled = clk_gate_shared_is_enabled, };
> +
> +struct clk_hw *imx_dev_clk_hw_gate_shared(struct device *dev, const char
> *name,
> +				const char *parent, void __iomem *reg,
> +				u8 shift, unsigned int *share_count) {
> +	struct clk_gate_shared *shgate;
> +	struct clk_gate *gate;
> +	struct clk_hw *hw;
> +	struct clk_init_data init;
> +	int ret;
> +
> +	shgate = kzalloc(sizeof(*shgate), GFP_KERNEL);
> +	if (!shgate)
> +		return ERR_PTR(-ENOMEM);
> +	gate = &shgate->gate;
> +
> +	init.name = name;
> +	init.ops = &clk_gate_shared_ops;
> +	init.flags = CLK_OPS_PARENT_ENABLE;
> +	init.parent_names = parent ? &parent : NULL;
> +	init.num_parents = parent ? 1 : 0;
> +
> +	gate->reg = reg;
> +	gate->bit_idx = shift;
> +	gate->lock = NULL;
> +	gate->hw.init = &init;
> +	shgate->lock = &imx_ccm_lock;
> +	shgate->share_count = share_count;
> +
> +	hw = &gate->hw;
> +
> +	ret = clk_hw_register(NULL, hw);
> +	if (ret) {
> +		kfree(shgate);
> +		return ERR_PTR(ret);
> +	}
> +
> +	return hw;
> +}
> diff --git a/drivers/clk/imx/clk.h b/drivers/clk/imx/clk.h index
> f074dd8..51d6c26 100644
> --- a/drivers/clk/imx/clk.h
> +++ b/drivers/clk/imx/clk.h
> @@ -151,6 +151,10 @@ struct clk_hw *imx_clk_hw_sscg_pll(const char
> *name,
>  				void __iomem *base,
>  				unsigned long flags);
> 
> +struct clk_hw *imx_dev_clk_hw_gate_shared(struct device *dev, const char
> *name,
> +				const char *parent, void __iomem *reg,
> +				u8 shift, unsigned int *share_count);
> +
>  enum imx_pllv3_type {
>  	IMX_PLLV3_GENERIC,
>  	IMX_PLLV3_SYS,
> --
> 2.7.4