linux-kernel - Re: [PATCH 1/2] clk: sunxi: Add support for A80 APBS clock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <CAGb2v64Jz49y+pUJe=FPw8Nh2rDo=-=+mXNVa4B7f_V2GjTfiw@mail.gmail.com>
Date:	Wed, 10 Feb 2016 11:25:28 +0800
From:	Chen-Yu Tsai <wens@...e.org>
To:	Maxime Ripard <maxime.ripard@...e-electrons.com>
Cc:	Chen-Yu Tsai <wens@...e.org>,
	Michael Turquette <mturquette@...libre.com>,
	Stephen Boyd <sboyd@...eaurora.org>,
	linux-clk <linux-clk@...r.kernel.org>,
	linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
	linux-kernel <linux-kernel@...r.kernel.org>,
	devicetree <devicetree@...r.kernel.org>
Subject: Re: [PATCH 1/2] clk: sunxi: Add support for A80 APBS clock

On Tue, Feb 2, 2016 at 7:15 PM, Maxime Ripard
<maxime.ripard@...e-electrons.com> wrote:
> Hi Chen-Yu
>
> On Mon, Feb 01, 2016 at 10:42:48PM +0800, Chen-Yu Tsai wrote:
>> A80's APBS clock is not the same as the APB0 clock on A23. The A80's
>> is a zero-based divider, while the A23's is a power-of-two divider.
>>
>> Signed-off-by: Chen-Yu Tsai <wens@...e.org>
>> ---
>>  Documentation/devicetree/bindings/clock/sunxi.txt |  1 +
>>  drivers/clk/sunxi/Makefile                        |  2 +-
>>  drivers/clk/sunxi/clk-sun9i-apbs.c                | 64 +++++++++++++++++++++++
>>  3 files changed, 66 insertions(+), 1 deletion(-)
>>  create mode 100644 drivers/clk/sunxi/clk-sun9i-apbs.c
>>
>> diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
>> index e59f57b24777..fad81157798c 100644
>> --- a/Documentation/devicetree/bindings/clock/sunxi.txt
>> +++ b/Documentation/devicetree/bindings/clock/sunxi.txt
>> @@ -58,6 +58,7 @@ Required properties:
>>       "allwinner,sun6i-a31-apb2-gates-clk" - for the APB2 gates on A31
>>       "allwinner,sun8i-a23-apb2-gates-clk" - for the APB2 gates on A23
>>       "allwinner,sun8i-h3-bus-gates-clk" - for the bus gates on H3
>> +     "allwinner,sun9i-a80-apbs-clk" - for the APBS clock on A80
>>       "allwinner,sun9i-a80-apbs-gates-clk" - for the APBS gates on A80
>>       "allwinner,sun4i-a10-dram-gates-clk" - for the DRAM gates on A10
>>       "allwinner,sun5i-a13-mbus-clk" - for the MBUS clock on A13
>> diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile
>> index 3fd7901d48e4..df433b3f789d 100644
>> --- a/drivers/clk/sunxi/Makefile
>> +++ b/drivers/clk/sunxi/Makefile
>> @@ -17,7 +17,7 @@ obj-y += clk-sun9i-core.o
>>  obj-y += clk-sun9i-mmc.o
>>  obj-y += clk-usb.o
>>
>> -obj-$(CONFIG_MACH_SUN9I) += clk-sun8i-apb0.o
>> +obj-$(CONFIG_MACH_SUN9I) += clk-sun9i-apbs.o
>>  obj-$(CONFIG_MACH_SUN9I) += clk-sun9i-cpus.o
>>
>>  obj-$(CONFIG_MFD_SUN6I_PRCM) += \
>> diff --git a/drivers/clk/sunxi/clk-sun9i-apbs.c b/drivers/clk/sunxi/clk-sun9i-apbs.c
>> new file mode 100644
>> index 000000000000..aacb92873621
>> --- /dev/null
>> +++ b/drivers/clk/sunxi/clk-sun9i-apbs.c
>> @@ -0,0 +1,64 @@
>> +/*
>> + * Copyright (C) 2016 Chen-Yu Tsai
>> + * Author: Chen-Yu Tsai <wens@...e.org>
>> + *
>> + * Allwinner A80 APBS clock driver
>> + *
>> + * License Terms: GNU General Public License v2
>> + *
>> + * Based on clk-sun6i-apbs.c
>> + * Allwinner A31 APB0 clock driver
>> + *
>> + * Copyright (C) 2014 Free Electrons
>> + * Author: Boris BREZILLON <boris.brezillon@...e-electrons.com>
>> + *
>> + */
>> +
>> +#include <linux/clk-provider.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_address.h>
>> +#include <linux/platform_device.h>
>> +
>> +static void sun9i_apbs_setup(struct device_node *node)
>> +{
>> +     const char *name = node->name;
>> +     const char *parent;
>> +     struct resource res;
>> +     struct clk *clk;
>> +     void __iomem *reg;
>> +     int ret;
>> +
>> +     reg = of_io_request_and_map(node, 0, of_node_full_name(node));
>> +     if (IS_ERR(reg)) {
>> +             pr_err("Could not get registers for a80-apbs-clk\n");
>> +             return;
>> +     }
>> +
>> +     parent = of_clk_get_parent_name(node, 0);
>> +     if (!parent)
>> +             return;
>> +
>> +     of_property_read_string(node, "clock-output-names", &name);
>> +
>> +     /* The A80 APBS clock is a standard 2 bit wide divider clock */
>> +     clk = clk_register_divider(NULL, name, parent, 0, reg, 0, 2, 0, NULL);
>> +     if (IS_ERR(clk)) {
>> +             pr_err("failed to register a80-apbs-clk: %ld\n", PTR_ERR(clk));
>> +             goto err_unmap;
>> +     }
>> +
>> +     ret = of_clk_add_provider(node, of_clk_src_simple_get, clk);
>> +     if (ret)
>> +             goto err_unregister;
>> +
>> +     return;
>> +
>> +err_unregister:
>> +     clk_unregister_divider(clk);
>> +err_unmap:
>> +     iounmap(reg);
>> +     of_address_to_resource(node, 0, &res);
>> +     release_mem_region(res.start, resource_size(&res));
>> +}
>> +CLK_OF_DECLARE(sun9i_apbs, "allwinner,sun9i-a80-apbs-clk", sun9i_apbs_setup);
>
> So it's just a different set of flags? Maybe we can simply reuse the
> same driver.

We could. I'll look into it.

ChenYu