[PATCH v2 05/13] clk: Versatile Express clock generators ("osc") driver

[Mike Turquette]

Quoting Pawel Moll (2012-09-18 07:17:47)
> This driver provides a common clock framework hardware driver
> for Versatile Express clock generators (a.k.a "osc") controlled
> via the config bus.
> 
> Signed-off-by: Pawel Moll <pawel.moll at arm.com>
> ---
>  drivers/clk/versatile/Makefile           |    1 +
>  drivers/clk/versatile/clk-vexpress-osc.c |  146 ++++++++++++++++++++++++++++++
>  2 files changed, 147 insertions(+)
>  create mode 100644 drivers/clk/versatile/clk-vexpress-osc.c
> 
> Hi Mike,
> 
> As agreed - this patch and the next one ("clk: Common clocks
> implementation for Versatile Express") are all yours.
> 

Taken into clk-next.

Thanks,
Mike

> Regards
> 
> Pawel
> 
> diff --git a/drivers/clk/versatile/Makefile b/drivers/clk/versatile/Makefile
> index c0a0f64..1e49a7a 100644
> --- a/drivers/clk/versatile/Makefile
> +++ b/drivers/clk/versatile/Makefile
> @@ -2,3 +2,4 @@
>  obj-$(CONFIG_ICST)             += clk-icst.o
>  obj-$(CONFIG_ARCH_INTEGRATOR)  += clk-integrator.o
>  obj-$(CONFIG_ARCH_REALVIEW)    += clk-realview.o
> +obj-$(CONFIG_VEXPRESS_CONFIG)  += clk-vexpress-osc.o
> diff --git a/drivers/clk/versatile/clk-vexpress-osc.c b/drivers/clk/versatile/clk-vexpress-osc.c
> new file mode 100644
> index 0000000..dcb6ae0
> --- /dev/null
> +++ b/drivers/clk/versatile/clk-vexpress-osc.c
> @@ -0,0 +1,146 @@
> +/*
> + * 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 in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * Copyright (C) 2012 ARM Limited
> + */
> +
> +#define pr_fmt(fmt) "vexpress-osc: " fmt
> +
> +#include <linux/clkdev.h>
> +#include <linux/clk-provider.h>
> +#include <linux/err.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/slab.h>
> +#include <linux/vexpress.h>
> +
> +struct vexpress_osc {
> +       struct vexpress_config_func *func;
> +       struct clk_hw hw;
> +       unsigned long rate_min;
> +       unsigned long rate_max;
> +};
> +
> +#define to_vexpress_osc(osc) container_of(osc, struct vexpress_osc, hw)
> +
> +static unsigned long vexpress_osc_recalc_rate(struct clk_hw *hw,
> +               unsigned long parent_rate)
> +{
> +       struct vexpress_osc *osc = to_vexpress_osc(hw);
> +       u32 rate;
> +
> +       vexpress_config_read(osc->func, 0, &rate);
> +
> +       return rate;
> +}
> +
> +static long vexpress_osc_round_rate(struct clk_hw *hw, unsigned long rate,
> +               unsigned long *parent_rate)
> +{
> +       struct vexpress_osc *osc = to_vexpress_osc(hw);
> +
> +       if (WARN_ON(osc->rate_min && rate < osc->rate_min))
> +               rate = osc->rate_min;
> +
> +       if (WARN_ON(osc->rate_max && rate > osc->rate_max))
> +               rate = osc->rate_max;
> +
> +       return rate;
> +}
> +
> +static int vexpress_osc_set_rate(struct clk_hw *hw, unsigned long rate,
> +               unsigned long parent_rate)
> +{
> +       struct vexpress_osc *osc = to_vexpress_osc(hw);
> +
> +       return vexpress_config_write(osc->func, 0, rate);
> +}
> +
> +static struct clk_ops vexpress_osc_ops = {
> +       .recalc_rate = vexpress_osc_recalc_rate,
> +       .round_rate = vexpress_osc_round_rate,
> +       .set_rate = vexpress_osc_set_rate,
> +};
> +
> +
> +struct clk * __init vexpress_osc_setup(struct device *dev)
> +{
> +       struct clk_init_data init;
> +       struct vexpress_osc *osc = kzalloc(sizeof(*osc), GFP_KERNEL);
> +
> +       if (!osc)
> +               return NULL;
> +
> +       osc->func = vexpress_config_func_get_by_dev(dev);
> +       if (!osc->func) {
> +               kfree(osc);
> +               return NULL;
> +       }
> +
> +       init.name = dev_name(dev);
> +       init.ops = &vexpress_osc_ops;
> +       init.flags = CLK_IS_ROOT;
> +       init.num_parents = 0;
> +       osc->hw.init = &init;
> +
> +       return clk_register(NULL, &osc->hw);
> +}
> +
> +void __init vexpress_osc_of_setup(struct device_node *node)
> +{
> +       struct clk_init_data init;
> +       struct vexpress_osc *osc;
> +       struct clk *clk;
> +       u32 range[2];
> +
> +       osc = kzalloc(sizeof(*osc), GFP_KERNEL);
> +       if (!osc)
> +               goto error;
> +
> +       osc->func = vexpress_config_func_get_by_node(node);
> +       if (!osc->func) {
> +               pr_err("Failed to obtain config func for node '%s'!\n",
> +                               node->name);
> +               goto error;
> +       }
> +
> +       if (of_property_read_u32_array(node, "freq-range", range,
> +                       ARRAY_SIZE(range)) == 0) {
> +               osc->rate_min = range[0];
> +               osc->rate_max = range[1];
> +       }
> +
> +       of_property_read_string(node, "clock-output-names", &init.name);
> +       if (!init.name)
> +               init.name = node->name;
> +
> +       init.ops = &vexpress_osc_ops;
> +       init.flags = CLK_IS_ROOT;
> +       init.num_parents = 0;
> +
> +       osc->hw.init = &init;
> +
> +       clk = clk_register(NULL, &osc->hw);
> +       if (IS_ERR(clk)) {
> +               pr_err("Failed to register clock '%s'!\n", init.name);
> +               goto error;
> +       }
> +
> +       of_clk_add_provider(node, of_clk_src_simple_get, clk);
> +
> +       pr_debug("Registered clock '%s'\n", init.name);
> +
> +       return;
> +
> +error:
> +       if (osc->func)
> +               vexpress_config_func_put(osc->func);
> +       kfree(osc);
> +}
> -- 
> 1.7.9.5