Subject: [PATCHv4 07/33] CLK: omap: add support for OMAP gate clock

From: [email-masked] (Nishanth Menon)
Date: Tue, 30 Jul 2013 14:17:28 -0500

On 07/23/2013 02:20 AM, Tero Kristo wrote:
> This node adds support for a clock node which allows control to the
> clockdomain enable / disable.

Dont we have clkdm_enable/disable for the same? should we model 
clockdomain as a clock node?

>
> Signed-off-by: Tero Kristo <[email-masked]>
> ---
>   drivers/clk/omap/Makefile |    2 +-
>   drivers/clk/omap/clk.c    |    1 +
>   drivers/clk/omap/gate.c   |   88 +++++++++++++++++++++++++++++++++++++++++++++
>   include/linux/clk/omap.h  |    1 +
>   4 files changed, 91 insertions(+), 1 deletion(-)
>   create mode 100644 drivers/clk/omap/gate.c
>

my usual crib: device tree binding documentation is missing

> diff --git a/drivers/clk/omap/Makefile b/drivers/clk/omap/Makefile
> index ca56700..3d3ca30f 100644
> --- a/drivers/clk/omap/Makefile
> +++ b/drivers/clk/omap/Makefile
> @@ -1 +1 @@
> -obj-y					+= clk.o dpll.o autoidle.o
> +obj-y					+= clk.o dpll.o autoidle.o gate.o
> diff --git a/drivers/clk/omap/clk.c b/drivers/clk/omap/clk.c
> index c149097..8c89714 100644
> --- a/drivers/clk/omap/clk.c
> +++ b/drivers/clk/omap/clk.c
> @@ -29,6 +29,7 @@ static const struct of_device_id clk_match[] = {
>   	{.compatible = "divider-clock", .data = of_omap_divider_setup, },
>   	{.compatible = "gate-clock", .data = of_gate_clk_setup, },
>   	{.compatible = "ti,omap4-dpll-clock", .data = of_omap4_dpll_setup, },
> +	{.compatible = "ti,gate-clock", .data = of_omap_gate_clk_setup, },

I am a little lost - is there any SoC dts that actually uses this? at 
least this series does not seem to introduce any node that uses this 
compatibility as per git grep :(

might as well drop the patch?

>   	{},
>   };
>
> diff --git a/drivers/clk/omap/gate.c b/drivers/clk/omap/gate.c
> new file mode 100644
> index 0000000..7186bb2
> --- /dev/null
> +++ b/drivers/clk/omap/gate.c
> @@ -0,0 +1,88 @@
> +/*
> + * OMAP gate clock support
> + *
> + * Copyright (C) 2013 Texas Instruments, Inc.
> + *
> + * Tero Kristo <[email-masked]>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed "as is" WITHOUT ANY WARRANTY of any
> + * kind, whether express or implied; without even the implied warranty
> + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/clk-provider.h>
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include <linux/io.h>
> +#include <linux/err.h>
> +#include <linux/string.h>
> +#include <linux/log2.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/clk/omap.h>
> +
> +#ifdef CONFIG_OF
> +
> +static const struct clk_ops omap_gate_clk_ops = {
> +	.init		= &omap2_init_clk_clkdm,
> +	.enable		= &omap2_clkops_enable_clkdm,
> +	.disable	= &omap2_clkops_disable_clkdm,
> +};
> +
> +void __init of_omap_gate_clk_setup(struct device_node *node)
> +{
> +	struct clk *clk;
> +	struct clk_init_data init;
init = { 0 };
> +	struct clk_hw_omap *clk_hw;
> +	const char *clk_name = node->name;
> +	int num_parents;
> +	const char **parent_names;
> +	int i;
> +
> +	clk_hw = kzalloc(sizeof(struct clk_hw_omap), GFP_KERNEL);
kzalloc(sizeof(*clk_hw)...) over kzalloc(sizeof(struct clk_hw_omap)...)

> +	if (!clk_hw) {
> +		pr_err("%s: could not allocate clk_hw_omap\n", __func__);
> +		return;
> +	}
> +
> +	clk_hw->hw.init = &init;
> +
> +	of_property_read_string(node, "clock-output-names", &clk_name);
> +	of_property_read_string(node, "ti,clkdm-name", &clk_hw->clkdm_name);
> +
> +	init.name = clk_name;
> +	init.ops = &omap_gate_clk_ops;
> +
> +	num_parents = of_clk_get_parent_count(node);
> +	if (num_parents < 1) {
> +		pr_err("%s: omap trace_clk %s must have parent(s)\n",
> +			__func__, node->name);
CHECK: Alignment should match open parenthesis

> +		goto cleanup;
> +	}
> +
> +	parent_names = kzalloc(sizeof(char *) * num_parents, GFP_KERNEL);
> +
> +	for (i = 0; i < num_parents; i++)
> +		parent_names[i] = of_clk_get_parent_name(node, i);
> +
> +	init.num_parents = num_parents;
> +	init.parent_names = parent_names;
> +
> +	clk = clk_register(NULL, &clk_hw->hw);
> +
> +	if (!IS_ERR(clk)) {
> +		of_clk_add_provider(node, of_clk_src_simple_get, clk);
> +		return;
> +	}
> +
> +cleanup:
kfree(parent_names)?
> +	kfree(clk_hw);
> +}
> +EXPORT_SYMBOL(of_omap_gate_clk_setup);
> +CLK_OF_DECLARE(omap_gate_clk, "ti,omap-gate-clock", of_omap_gate_clk_setup);
> +#endif
> diff --git a/include/linux/clk/omap.h b/include/linux/clk/omap.h
> index 904bdad..58ebb80 100644
> --- a/include/linux/clk/omap.h
> +++ b/include/linux/clk/omap.h
> @@ -194,6 +194,7 @@ extern void omap_dt_clocks_register(struct omap_dt_clk *oclks, int cnt);
>   void of_omap4_dpll_setup(struct device_node *node);
>   void of_omap_fixed_factor_setup(struct device_node *node);
>   void of_omap_divider_setup(struct device_node *node);
> +void of_omap_gate_clk_setup(struct device_node *node);
dont need to export I think if we use strategy mentioned previously.

>   void of_omap_clk_allow_autoidle_all(void);
>   void of_omap_clk_deny_autoidle_all(void);
>
>

-- 
Regards,
Nishanth Menon