Re: [PATCH v2 06/26] clk: sunxi: Add PLL3 clock

Chen-Yu Tsai
2016-01-16T16:05:06Z

Hi,

On Thu, Jan 14, 2016 at 11:24 PM, Maxime Ripard
<maxime.ripard@free-electrons.com> wrote:
> The A10 SoCs and relatives have a PLL controller to drive the PLL3 and
> PLL7, clocked from a 3MHz oscillator, that drives the display related
> clocks (GPU, display engine, TCON, etc.)
>
> Add a driver for it.
>
> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
> ---
> Documentation/devicetree/bindings/clock/sunxi.txt | 1 +
> drivers/clk/sunxi/Makefile | 1 +
> drivers/clk/sunxi/clk-sun4i-pll3.c | 90 +++++++++++++++++++++++
> 3 files changed, 92 insertions(+)
> create mode 100644 drivers/clk/sunxi/clk-sun4i-pll3.c
>
> diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
> index 5360554a7d3f..bb9fb78dcff8 100644
> --- a/Documentation/devicetree/bindings/clock/sunxi.txt
> +++ b/Documentation/devicetree/bindings/clock/sunxi.txt
> @@ -10,6 +10,7 @@ Required properties:
> "allwinner,sun4i-a10-pll1-clk" - for the main PLL clock and PLL4
> "allwinner,sun6i-a31-pll1-clk" - for the main PLL clock on A31
> "allwinner,sun8i-a23-pll1-clk" - for the main PLL clock on A23
> + "allwinner,sun4i-a10-pll3-clk" - for the video PLL clock on A10
> "allwinner,sun9i-a80-pll4-clk" - for the peripheral PLLs on A80
> "allwinner,sun4i-a10-pll5-clk" - for the PLL5 clock
> "allwinner,sun4i-a10-pll6-clk" - for the PLL6 clock
> diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile
> index a991cd8ca509..40c32ffd912c 100644
> --- a/drivers/clk/sunxi/Makefile
> +++ b/drivers/clk/sunxi/Makefile
> @@ -11,6 +11,7 @@ obj-y += clk-a20-gmac.o
> obj-y += clk-mod0.o
> obj-y += clk-simple-gates.o
> obj-y += clk-sun4i-display.o
> +obj-y += clk-sun4i-pll3.o
> obj-y += clk-sun8i-mbus.o
> obj-y += clk-sun9i-core.o
> obj-y += clk-sun9i-mmc.o
> diff --git a/drivers/clk/sunxi/clk-sun4i-pll3.c b/drivers/clk/sunxi/clk-sun4i-pll3.c
> new file mode 100644
> index 000000000000..6c9c2210b6b2
> --- /dev/null
> +++ b/drivers/clk/sunxi/clk-sun4i-pll3.c
> @@ -0,0 +1,90 @@
> +/*
> + * Copyright 2015 Maxime Ripard
> + *
> + * Maxime Ripard <maxime.ripard@free-electrons.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * 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.
> + */
> +
> +#include <linux/clk-provider.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +
> +#define SUN4I_A10_PLL3_GATE_BIT 31
> +#define SUN4I_A10_PLL3_DIV_WIDTH 7
> +#define SUN4I_A10_PLL3_DIV_SHIFT 0
> +
> +static DEFINE_SPINLOCK(sun4i_a10_pll3_lock);
> +
> +static void __init sun4i_a10_pll3_setup(struct device_node *node)
> +{
> + const char *clk_name = node->name, *parent;
> + struct clk_multiplier *mult;
> + struct clk_gate *gate;
> + void __iomem *reg;
> + struct clk *clk;
> + int ret;
> +
> + of_property_read_string(node, "clock-output-names", &clk_name);
> + parent = of_clk_get_parent_name(node, 0);
> +
> + reg = of_io_request_and_map(node, 0, of_node_full_name(node));
> + if (IS_ERR(reg)) {
> + pr_err("%s: Could not map the clock registers\n", clk_name);
> + return;
> + }
> +
> + gate = kzalloc(sizeof(*gate), GFP_KERNEL);
> + if (!gate)
> + return;
> +
> + gate->reg = reg;
> + gate->bit_idx = SUN4I_A10_PLL3_GATE_BIT;
> + gate->lock = &sun4i_a10_pll3_lock;
> +
> + mult = kzalloc(sizeof(*mult), GFP_KERNEL);
> + if (!mult)
> + goto err_free_gate;
> +
> + mult->reg = reg;
> + mult->shift = SUN4I_A10_PLL3_DIV_SHIFT;
> + mult->width = SUN4I_A10_PLL3_DIV_WIDTH;
> + mult->lock = &sun4i_a10_pll3_lock;
> +
> + clk = clk_register_composite(NULL, clk_name,
> + &parent, 1,
> + NULL, NULL,
> + &mult->hw, &clk_multiplier_ops,
> + &gate->hw, &clk_gate_ops,
> + 0);
> + if (IS_ERR(clk)) {
> + pr_err("%s: Couldn't register the clock\n", clk_name);
> + goto err_free_mult;
> + }
> +
> + ret = of_clk_add_provider(node, of_clk_src_simple_get, clk);
> + if (WARN_ON(ret))

Any particular reason for WARN_ON instead of pr_err like above?

> + goto err_clk_unregister;
> +
> + return;
> +
> +err_clk_unregister:
> + clk_unregister_composite(clk);
> +err_free_mult:
> + kfree(mult);
> +err_free_gate:
> + kfree(gate);

Clean up after of_io_request_and_map(), otherwise

Acked-by: Chen-Yu Tsai <wens@csie.org>

Thanks!

> +}
> +
> +CLK_OF_DECLARE(sun4i_a10_pll3, "allwinner,sun4i-a10-pll3-clk",
> + sun4i_a10_pll3_setup);
> --
> 2.6.4
>