Re: [PATCH 08/17] clk: Add PLX Technology OXNAS Standard Clocks

From: Neil Armstrong
Date: Mon Mar 07 2016 - 06:24:57 EST


On 03/04/2016 03:25 AM, Stephen Boyd wrote:
> On 03/03, Neil Armstrong wrote:
>> diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
>> index eca8e01..b75ef5c 100644
>> --- a/drivers/clk/Kconfig
>> +++ b/drivers/clk/Kconfig
>> @@ -192,6 +192,12 @@ config COMMON_CLK_PXA
>> ---help---
>> Sypport for the Marvell PXA SoC.
>>
>> +config COMMON_CLK_OXNAS
>> + def_bool COMMON_CLK
>> + select MFD_SYSCON
>
> So this is always built if I have the common clk framework
> enabled? Not good.
Fixed.

>> +#include <linux/clk.h>
>> +#include <linux/clkdev.h>
>
> Are either of these includes used?
>
>> +#include <linux/clk-provider.h>
>> +#include <linux/of.h>
>> +#include <linux/delay.h>
>
> Is this include used?
>
>> +#include <linux/stringify.h>
>> +#include <linux/reset.h>
>
> Is this include used?
>
>> +#include <linux/io.h>
>
> Is this include used?
>
>> +#include <linux/regmap.h>
>> +#include <linux/mfd/syscon.h>
>
> #include <linux/kernel.h> for container_of?

Fixed an cleaned up, thanks.


>> +static int std_clk_enable(struct clk_hw *hw)
>> +{
>> + struct clk_std *std = to_stdclk(hw);
>> +
>> + regmap_write(std->regmap, CLK_SET_REGOFFSET, BIT(std->bit));
>
> I hope the regmap is fast_io? Otherwise this is scheduling while
> atomic.
Yes, but due to the nature of the registers, I can't use the clk-regmap module.

>> +
>> + return 0;
>> +}
>> +
>> +static void std_clk_disable(struct clk_hw *hw)
>> +{
>> + struct clk_std *std = to_stdclk(hw);
>> +
>> + regmap_write(std->regmap, CLK_CLR_REGOFFSET, BIT(std->bit));
>> +}
>> +
>> +static struct clk_ops std_clk_ops = {
>
> const?
>
>> + .enable = std_clk_enable,
>> + .disable = std_clk_disable,
>> + .is_enabled = std_clk_is_enabled,
>> +};
>> +
> [..]
>> +
>> +static struct clk_hw *std_clk_hw_tbl[] = {
>
> const?
>
>> + &clk_leon.hw,
>> + &clk_dma_sgdma.hw,
>> + &clk_cipher.hw,
>> + &clk_sata.hw,
>> + &clk_audio.hw,
>> + &clk_usbmph.hw,
>> + &clk_etha.hw,
>> + &clk_pciea.hw,
>> + &clk_nand.hw,
>> +};
>> +
>> +static struct clk *std_clk_tbl[ARRAY_SIZE(std_clk_hw_tbl)];
>> +
>> +static struct clk_onecell_data std_clk_data;
>
> These are pretty generic. Perhaps oxnas_clk_data and
> oxnas_clk_hw_tbl?
>
>> +
>> +static void __init oxnas_init_stdclk(struct device_node *np)
>> +{
>> + int i;
>> + struct regmap *regmap = syscon_node_to_regmap(of_get_parent(np));
>> +
>> + if (!regmap)
>> + panic("failed to have parent regmap\n");
>> +
>> + for (i = 0; i < ARRAY_SIZE(std_clk_hw_tbl); i++) {
>> + struct clk_std *std = container_of(std_clk_hw_tbl[i],
>> + struct clk_std, hw);
>> +
>> + if (WARN_ON(!std))
>> + return;
>> + std->regmap = regmap;
>> +
>> + std_clk_tbl[i] = clk_register(NULL, std_clk_hw_tbl[i]);
>> + if (WARN_ON(IS_ERR(std_clk_tbl[i])))
>> + return;
>> + }
>> +
>> + std_clk_data.clks = std_clk_tbl;
>> + std_clk_data.clk_num = ARRAY_SIZE(std_clk_tbl);
>> +
>> + of_clk_add_provider(np, of_clk_src_onecell_get, &std_clk_data);
>> +}
>> +CLK_OF_DECLARE(oxnas_pllstd, "plxtech,ox810se-stdclk", oxnas_init_stdclk);
>
> Can this be a platform driver instead?
>
> Is there a binding for this compatible?

I refactored the driver to be platform driver and cleaned up the structure to be const and allocate the clocks at probe.

The bindings was in a separate patch, I forgot to CC linux-clk :
http://lkml.kernel.org/r/1457005210-18485-10-git-send-email-narmstrong@xxxxxxxxxxxx

In the meantime I added the indices description in the bindings.

Neil