Re: [PATCH v3 2/2] clk: meson: add sub MMC clock controller driver

[Yixun Lan]

HI Stephen:

On 07/26/2018 11:20 PM, Stephen Boyd wrote:
> Quoting Yixun Lan (2018-07-12 14:12:44)
>> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
>> new file mode 100644
>> index 000000000000..36c4c7cd69a6
>> --- /dev/null
>> +++ b/drivers/clk/meson/mmc-clkc.c
>> @@ -0,0 +1,367 @@
>> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
>> +/*
>> + * Amlogic Meson MMC Sub Clock Controller Driver
>> + *
>> + * Copyright (c) 2017 Baylibre SAS.
>> + * Author: Jerome Brunet <jbrunet@xxxxxxxxxxxx>
>> + *
>> + * Copyright (c) 2018 Amlogic, inc.
>> + * Author: Yixun Lan <yixun.lan@xxxxxxxxxxx>
>> + */
>> +
>> +#include <linux/clk.h>
> 
> Is this include used?
> 
this is needed by clk_get_rate()
see drivers/clk/meson/mmc-clkc.c:204

>> +#include <linux/clk-provider.h>
>> +#include <linux/module.h>
>> +#include <linux/regmap.h>
>> +#include <linux/slab.h>
>> +#include <linux/of_device.h>
>> +#include <linux/mfd/syscon.h>
>> +#include <linux/platform_device.h>
>> +#include <dt-bindings/clock/amlogic,meson-mmc-clkc.h>
>> +
>> +#include "clkc.h"
>> +
>> +
>> +static struct clk_regmap *
>> +mmc_clkc_register_other_clk(struct device *dev, struct regmap *map,
>> +                           char *suffix, char *parent_suffix,
>> +                           unsigned long flags,
>> +                           const struct clk_ops *ops, void *data)
>> +{
>> +       struct clk_init_data init;
>> +       struct clk_regmap *clk;
>> +       char *parent;
>> +
>> +       parent = kasprintf(GFP_KERNEL, "%s#%s", dev_name(dev), parent_suffix);
>> +       if (!parent)
>> +               return ERR_PTR(-ENOMEM);
>> +
>> +       init.ops = ops;
>> +       init.flags = flags;
>> +       init.parent_names = (const char* const []){ parent, };
> 
> Can't this just be &parent?
sure, I can fix this

> 
>> +       init.num_parents = 1;
>> +
>> +       clk = mmc_clkc_register_clk(dev, map, &init, suffix, data);
>> +       if (IS_ERR(clk))
>> +               dev_err(dev, "Core %s clock registration failed\n", suffix);
>> +
>> +       kfree(parent);
>> +       return clk;
>> +}
>> +
>> +static int mmc_clkc_probe(struct platform_device *pdev)
>> +{
>> +       struct clk_hw_onecell_data *onecell_data;
>> +       struct device *dev = &pdev->dev;
>> +       struct mmc_clkc_data *data;
>> +       struct regmap *map;
>> +       struct clk_regmap *mux, *div, *core, *rx, *tx;
>> +
>> +       data = (struct mmc_clkc_data *)of_device_get_match_data(dev);
> 
> This cast is unnecessary. Pleas remove.
> 
Ok, I will try to fix in next version


this was trying to silence the âconstâ cast warning [1]
I could make a 'const struct mmc_clkc_data *data' declare, but need to
fix further cast warning issue..


[1] drivers/clk/meson/mmc-clkc.c: In function âmmc_clkc_probeâ:
drivers/clk/meson/mmc-clkc.c:302:7: warning: assignment discards âconstâ
qualifier from pointer target type [-Wdiscarded-qualifiers]
  data = of_device_get_match_data(dev);
       ^