[PATCH v2 1/9] clk: sunxi: Add support for sun9i a80 usb clocks and resets
Chen-Yu Tsai
wens at csie.org
Mon Jan 26 01:25:49 PST 2015
Hi,
2015年1月25日 下午11:05 於 "Maxime Ripard" <maxime.ripard at free-electrons.com> 寫道：
>
> Hi,
>
> On Sun, Jan 25, 2015 at 08:22:02PM +0800, Chen-Yu Tsai wrote:
> > The USB controller/phy clocks and reset controls are in a separate
> > address block, unlike previous SoCs where they were in the clock
> > controller.
> >
> > This patch copies the original gates clk functions used for usb
> > clocks into a separate file, and renames them to *_usb_*. Also
> > add a per-gate parent index, so we can set different parents for
> > each gate.
> >
> > Signed-off-by: Chen-Yu Tsai <wens at csie.org>
> > ---
> > Documentation/devicetree/bindings/clock/sunxi.txt | 2 +
> > drivers/clk/sunxi/Makefile | 1 +
> > drivers/clk/sunxi/clk-usb.c | 193 ++++++++++++++++++++++
> > 3 files changed, 196 insertions(+)
> > create mode 100644 drivers/clk/sunxi/clk-usb.c
> >
> > diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
> > index 60b44285250d..3f1dcd879af7 100644
> > --- a/Documentation/devicetree/bindings/clock/sunxi.txt
> > +++ b/Documentation/devicetree/bindings/clock/sunxi.txt
> > @@ -66,6 +66,8 @@ Required properties:
> > "allwinner,sun4i-a10-usb-clk" - for usb gates + resets on A10 / A20
> > "allwinner,sun5i-a13-usb-clk" - for usb gates + resets on A13
> > "allwinner,sun6i-a31-usb-clk" - for usb gates + resets on A31
> > + "allwinner,sun9i-a80-usb-mod-clk" - for usb gates + resets on A80
> > + "allwinner,sun9i-a80-usb-phy-clk" - for usb phy gates + resets on A80
> >
> > Required properties for all clocks:
> > - reg : shall be the control register address for the clock.
> > diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile
> > index 3a5292e3fcf8..058f273d6154 100644
> > --- a/drivers/clk/sunxi/Makefile
> > +++ b/drivers/clk/sunxi/Makefile
> > @@ -9,6 +9,7 @@ obj-y += clk-mod0.o
> > obj-y += clk-sun8i-mbus.o
> > obj-y += clk-sun9i-core.o
> > obj-y += clk-sun9i-mmc.o
> > +obj-y += clk-usb.o
>
> Is that supposed to handle the other USB clocks in the future as well?
I plan to do that. If you compare this and the original USB clk driver,
you'll notice it's pretty much the same.
> >
> > obj-$(CONFIG_MFD_SUN6I_PRCM) += \
> > clk-sun6i-ar100.o clk-sun6i-apb0.o clk-sun6i-apb0-gates.o \
> > diff --git a/drivers/clk/sunxi/clk-usb.c b/drivers/clk/sunxi/clk-usb.c
> > new file mode 100644
> > index 000000000000..1a93400353de
> > --- /dev/null
> > +++ b/drivers/clk/sunxi/clk-usb.c
> > @@ -0,0 +1,193 @@
> > +/*
> > + * Copyright 2013 Emilio López
> > + *
> > + * Emilio López <emilio at elopez.com.ar>
>
> Hmmmm, the copyright notice seems weird :)
The code was pulled from clk-sunxi.c, which only has Emilio's
copyright. I suppose I could dig up who actually wrote the code.
I think it was Hans.
> > + *
> > + * 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/clkdev.h>
> > +#include <linux/of.h>
> > +#include <linux/of_address.h>
> > +#include <linux/reset-controller.h>
> > +#include <linux/spinlock.h>
> > +
> > +
> > +/**
> > + * sunxi_usb_reset... - reset bits in usb clk registers handling
> > + */
> > +
> > +struct usb_reset_data {
> > + void __iomem *reg;
> > + spinlock_t *lock;
> > + struct clk *clk;
> > + struct reset_controller_dev rcdev;
> > +};
> > +
> > +static int sunxi_usb_reset_assert(struct reset_controller_dev *rcdev,
> > + unsigned long id)
> > +{
> > + struct usb_reset_data *data = container_of(rcdev,
> > + struct usb_reset_data,
> > + rcdev);
> > + unsigned long flags;
> > + u32 reg;
> > +
> > + clk_prepare_enable(data->clk);
> > + spin_lock_irqsave(data->lock, flags);
> > +
> > + reg = readl(data->reg);
> > + writel(reg & ~BIT(id), data->reg);
> > +
> > + spin_unlock_irqrestore(data->lock, flags);
> > + clk_disable_unprepare(data->clk);
> > +
> > + return 0;
> > +}
> > +
> > +static int sunxi_usb_reset_deassert(struct reset_controller_dev *rcdev,
> > + unsigned long id)
> > +{
> > + struct usb_reset_data *data = container_of(rcdev,
> > + struct usb_reset_data,
> > + rcdev);
> > + unsigned long flags;
> > + u32 reg;
> > +
> > + clk_prepare_enable(data->clk);
> > + spin_lock_irqsave(data->lock, flags);
> > +
> > + reg = readl(data->reg);
> > + writel(reg | BIT(id), data->reg);
> > +
> > + spin_unlock_irqrestore(data->lock, flags);
> > + clk_disable_unprepare(data->clk);
> > +
> > + return 0;
> > +}
> > +
> > +static struct reset_control_ops sunxi_usb_reset_ops = {
> > + .assert = sunxi_usb_reset_assert,
> > + .deassert = sunxi_usb_reset_deassert,
> > +};
> > +
> > +/**
> > + * sunxi_usb_clk_setup() - Setup function for usb gate clocks
> > + */
> > +
> > +#define SUNXI_USB_MAX_SIZE 32
> > +
> > +struct usb_clk_data {
> > + u32 clk_mask;
> > + u32 reset_mask;
> > + bool reset_needs_clk;
> > +};
> > +
> > +static void __init sunxi_usb_clk_setup(struct device_node *node,
> > + const struct usb_clk_data *data,
> > + spinlock_t *lock)
> > +{
> > + struct clk_onecell_data *clk_data;
> > + struct usb_reset_data *reset_data;
> > + const char *clk_parent;
> > + const char *clk_name;
> > + void __iomem *reg;
> > + int qty;
> > + int i = 0;
> > + int j = 0;
> > +
> > + reg = of_io_request_and_map(node, 0, of_node_full_name(node));
>
> You should check the return code here.
Right.
> > + clk_parent = of_clk_get_parent_name(node, 0);
> > + if (!clk_parent)
> > + return;
> > +
> > + /* Worst-case size approximation and memory allocation */
> > + qty = find_last_bit((unsigned long *)&data->clk_mask,
> > + SUNXI_USB_MAX_SIZE);
>
> Newline
OK.
> > + clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
> > + if (!clk_data)
> > + return;
>
> Newline.
OK.
> > + clk_data->clks = kzalloc((qty+1) * sizeof(struct clk *), GFP_KERNEL);
> > + if (!clk_data->clks) {
> > + kfree(clk_data);
> > + return;
> > + }
> > +
> > + for_each_set_bit(i, (unsigned long *)&data->clk_mask,
> > + SUNXI_USB_MAX_SIZE) {
> > + of_property_read_string_index(node, "clock-output-names",
> > + j, &clk_name);
> > + clk_data->clks[i] = clk_register_gate(NULL, clk_name,
> > + clk_parent, 0,
> > + reg, i, 0, lock);
> > + WARN_ON(IS_ERR(clk_data->clks[i]));
> > + clk_register_clkdev(clk_data->clks[i], clk_name, NULL);
>
> Do we really need to use clkdev for these clocks?
Original code. I don't think we do.
> > + j++;
> > + }
> > +
> > + /* Adjust to the real max */
> > + clk_data->clk_num = i;
> > +
> > + of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
> > +
> > + /* Register a reset controller for usb with reset bits */
> > + if (data->reset_mask == 0)
> > + return;
> > +
> > + reset_data = kzalloc(sizeof(*reset_data), GFP_KERNEL);
> > + if (!reset_data)
> > + return;
> > +
> > + if (data->reset_needs_clk)
> > + reset_data->clk = of_clk_get(node, 0);
>
> Newline
OK.
> > + if (IS_ERR(reset_data->clk)) {
> > + pr_err("Could not get clock for reset controls\n");
> > + kfree(reset_data);
> > + return;
> > + }
>
> Newline, and that block should probably be part of the if block above.
NULL is not considered an error, but maybe being in the same block
makes it clear that they are related.
> > + reset_data->reg = reg;
> > + reset_data->lock = lock;
> > + reset_data->rcdev.nr_resets = __fls(data->reset_mask) + 1;
> > + reset_data->rcdev.ops = &sunxi_usb_reset_ops;
> > + reset_data->rcdev.of_node = node;
> > + reset_controller_register(&reset_data->rcdev);
> > +}
> > +
> > +static const struct usb_clk_data sun9i_a80_usb_mod_data __initconst = {
> > + .clk_mask = BIT(6) | BIT(5) | BIT(4) | BIT(3) | BIT(2) | BIT(1),
> > + .reset_mask = BIT(19) | BIT(18) | BIT(17),
> > + .reset_needs_clk = 1,
> > +};
> > +
> > +static DEFINE_SPINLOCK(a80_usb_mod_lock);
> > +
> > +static void __init sun9i_a80_usb_mod_setup(struct device_node *node)
> > +{
> > + sunxi_usb_clk_setup(node, &sun9i_a80_usb_mod_data, &a80_usb_mod_lock);
> > +}
> > +CLK_OF_DECLARE(sun9i_a80_usb_mod, "allwinner,sun9i-a80-usb-mod-clk", sun9i_a80_usb_mod_setup);
> > +
> > +static const struct usb_clk_data sun9i_a80_usb_phy_data __initconst = {
> > + .clk_mask = BIT(10) | BIT(5) | BIT(4) | BIT(3) | BIT(2) | BIT(1),
> > + .reset_mask = BIT(21) | BIT(20) | BIT(19) | BIT(18) | BIT(17),
> > + .reset_needs_clk = 1,
> > +};
> > +
> > +static DEFINE_SPINLOCK(a80_usb_phy_lock);
> > +
> > +static void __init sun9i_a80_usb_phy_setup(struct device_node *node)
> > +{
> > + sunxi_usb_clk_setup(node, &sun9i_a80_usb_phy_data, &a80_usb_phy_lock);
> > +}
> > +CLK_OF_DECLARE(sun9i_a80_usb_phy, "allwinner,sun9i-a80-usb-phy-clk", sun9i_a80_usb_phy_setup);
>
> Looks good otherwise, thanks!
Thanks.
ChenYu
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