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

From: Chen-Yu Tsai
Date: Tue Feb 09 2016 - 22:26:06 EST


On Tue, Feb 2, 2016 at 7:15 PM, Maxime Ripard
<maxime.ripard@xxxxxxxxxxxxxxxxxx> 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@xxxxxxxx>
>> ---
>> 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@xxxxxxxx>
>> + *
>> + * 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@xxxxxxxxxxxxxxxxxx>
>> + *
>> + */
>> +
>> +#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