diff mbox series

[v9,4/4] clk: meson: add sub MMC clock controller driver

Message ID 20220113115745.45826-5-liang.yang@amlogic.com (mailing list archive)
State Superseded
Delegated to: Neil Armstrong
Headers show
Series clk: meson: add a sub EMMC clock controller support | expand

Commit Message

Liang Yang Jan. 13, 2022, 11:57 a.m. UTC 
The patch will add a MMC clock controller driver which used by MMC or NAND,
It provide a mux and divider clock, and three phase clocks - core, tx, tx.

Two clocks are provided as the parent of MMC clock controller from
upper layer clock controller - eg "amlogic,axg-clkc" in AXG platform.

To specify which clock the MMC or NAND driver may consume,
the preprocessor macros in the dt-bindings/clock/amlogic,mmc-clkc.h header
can be used in the device tree sources.

Signed-off-by: Liang Yang <liang.yang@amlogic.com>
---
 drivers/clk/meson/Kconfig    |  14 ++
 drivers/clk/meson/Makefile   |   1 +
 drivers/clk/meson/mmc-clkc.c | 300 +++++++++++++++++++++++++++++++++++
 3 files changed, 315 insertions(+)
 create mode 100644 drivers/clk/meson/mmc-clkc.c

Comments

Stephen Boyd Jan. 13, 2022, 9:35 p.m. UTC | #1 
Quoting Liang Yang (2022-01-13 03:57:45)
> diff --git a/drivers/clk/meson/Kconfig b/drivers/clk/meson/Kconfig
> index bb0f59eea366..3de6f3b24461 100644
> --- a/drivers/clk/meson/Kconfig
> +++ b/drivers/clk/meson/Kconfig
> @@ -39,6 +39,20 @@ config COMMON_CLK_MESON_AO_CLKC
>         select COMMON_CLK_MESON_REGMAP
>         select RESET_CONTROLLER
>  
> +config COMMON_CLK_MMC_MESON
> +       tristate "Meson MMC Sub Clock Controller Driver"
> +       depends on ARCH_MESON || COMPILE_TEST
> +       select MFD_SYSCON
> +       select COMMON_CLK_AMLOGIC
> +       select COMMON_CLK_MESON_PHASE
> +       select COMMON_CLK_MESON_PHASE_DELAY
> +       select COMMON_CLK_MESON_SCLK_DIV
> +       help
> +         Support for the MMC sub clock controller on
> +         Amlogic Meson Platform, which includes S905 (GXBB, GXL),
> +         A113D/X (AXG) devices . Say Y if you want this

s/devices /devices/

> +         clock enabled.
> +
>  config COMMON_CLK_MESON_EE_CLKC
>         tristate
>         select COMMON_CLK_MESON_REGMAP
> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
> new file mode 100644
> index 000000000000..f53977f61390
> --- /dev/null
> +++ b/drivers/clk/meson/mmc-clkc.c
> @@ -0,0 +1,300 @@
> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
> +/*
> + * Copyright (c) 2019 Amlogic, Inc. All rights reserved.
> + */
> +
> +#include <linux/clk.h>
> +#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,mmc-clkc.h>
> +
> +#include "sclk-div.h"
> +#include "clk-phase-delay.h"
> +#include "clk-regmap.h"
> +#include "clk-phase.h"
> +
> +/* clock ID used by internal driver */
> +
> +#define SD_EMMC_CLOCK          0
> +#define CLK_DELAY_STEP_PS_GX   200
> +#define CLK_DELAY_STEP_PS_AXG  78
> +#define MUX_CLK_NUM_PARENTS    2
> +#define MMC_MAX_CLKS           4
> +
> +struct mmc_clkc_data {
> +       struct meson_clk_phase_delay_data tx;
> +       struct meson_clk_phase_delay_data rx;
> +};
> +
> +static struct clk_regmap_mux_data mmc_clkc_mux_data = {
> +       .offset = SD_EMMC_CLOCK,
> +       .mask   = 0x3,
> +       .shift  = 6,
> +};
> +
> +static const struct meson_sclk_div_data mmc_clkc_div_data = {
> +       .div = {
> +               .reg_off = SD_EMMC_CLOCK,
> +               .width   = 6,
> +       },
> +       .flags = MESON_SCLK_ONE_BASED,
> +};
> +
> +static struct meson_clk_phase_data mmc_clkc_core_phase = {
> +       .ph = {
> +               .reg_off = SD_EMMC_CLOCK,
> +               .shift   = 8,
> +               .width   = 2,
> +       }
> +};
> +
> +static const struct mmc_clkc_data mmc_clkc_gx_data = {
> +       .tx = {
> +               .phase = {
> +                       .reg_off = SD_EMMC_CLOCK,
> +                       .shift   = 10,
> +                       .width   = 2,
> +               },
> +               .delay = {
> +                       .reg_off = SD_EMMC_CLOCK,
> +                       .shift   = 16,
> +                       .width   = 4,
> +               },
> +               .delay_step_ps = CLK_DELAY_STEP_PS_GX,
> +       },
> +       .rx = {
> +               .phase = {
> +                       .reg_off = SD_EMMC_CLOCK,
> +                       .shift   = 12,
> +                       .width   = 2,
> +               },
> +               .delay = {
> +                       .reg_off = SD_EMMC_CLOCK,
> +                       .shift   = 20,
> +                       .width   = 4,
> +               },
> +               .delay_step_ps   = CLK_DELAY_STEP_PS_GX,
> +       },
> +};
> +
> +static const struct mmc_clkc_data mmc_clkc_axg_data = {
> +       .tx = {
> +               .phase = {
> +                       .reg_off = SD_EMMC_CLOCK,
> +                       .shift   = 10,
> +                       .width   = 2,
> +               },
> +               .delay = {
> +                       .reg_off = SD_EMMC_CLOCK,
> +                       .shift   = 16,
> +                       .width   = 6,
> +               },
> +               .delay_step_ps   = CLK_DELAY_STEP_PS_AXG,
> +       },
> +       .rx = {
> +               .phase = {
> +                       .reg_off = SD_EMMC_CLOCK,
> +                       .shift   = 12,
> +                       .width   = 2,
> +               },
> +               .delay = {
> +                       .reg_off = SD_EMMC_CLOCK,
> +                       .shift   = 22,
> +                       .width   = 6,
> +               },
> +               .delay_step_ps   = CLK_DELAY_STEP_PS_AXG,
> +       },
> +};
> +
> +static const struct of_device_id mmc_clkc_match_table[] = {
> +       {
> +               .compatible     = "amlogic,gx-mmc-clkc",
> +               .data           = &mmc_clkc_gx_data
> +       },
> +       {
> +               .compatible     = "amlogic,axg-mmc-clkc",
> +               .data           = &mmc_clkc_axg_data
> +       },
> +       {}
> +};
> +MODULE_DEVICE_TABLE(of, mmc_clkc_match_table);
> +
> +static struct clk_regmap *
> +mmc_clkc_register_clk(struct device *dev, struct regmap *map,
> +                     struct clk_init_data *init,
> +                     const char *suffix, void *data)
> +{
> +       struct clk_regmap *clk;
> +       char *name;
> +       int ret;
> +
> +       clk = devm_kzalloc(dev, sizeof(*clk), GFP_KERNEL);
> +       if (!clk)
> +               return ERR_PTR(-ENOMEM);
> +
> +       name = kasprintf(GFP_KERNEL, "%s#%s", dev_name(dev), suffix);
> +       if (!name)
> +               return ERR_PTR(-ENOMEM);
> +
> +       init->name = name;
> +       clk->map = map;
> +       clk->data = data;
> +       clk->hw.init = init;
> +       ret = devm_clk_hw_register(dev, &clk->hw);
> +       if (ret)
> +               clk = ERR_PTR(ret);
> +
> +       kfree(name);
> +       return clk;
> +}
> +
> +static struct clk_regmap *mmc_clkc_register_mux(struct device *dev,
> +                                               struct regmap *map)
> +{
> +       const char *parent_names[MUX_CLK_NUM_PARENTS];
> +       struct clk_init_data init;
> +       struct clk_regmap *mux;
> +       struct clk *clk;
> +       int i;
> +
> +       for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
> +               char name[8];
> +
> +               snprintf(name, sizeof(name), "clkin%d", i);
> +               clk = devm_clk_get(dev, name);
> +               if (IS_ERR(clk)) {
> +                       if (clk != ERR_PTR(-EPROBE_DEFER))
> +                               dev_err(dev, "Missing clock %s\n", name);

Use dev_err_probe()?

> +                       return ERR_CAST(clk);
> +               }
> +
> +               parent_names[i] = __clk_get_name(clk);

Why can't we use clk_parent_data?

> +       }
> +
> +       init.ops = &clk_regmap_mux_ops;
> +       init.flags = CLK_SET_RATE_PARENT;
> +       init.parent_names = parent_names;
> +       init.num_parents = MUX_CLK_NUM_PARENTS;
> +
> +       mux = mmc_clkc_register_clk(dev, map, &init, "mux", &mmc_clkc_mux_data);
> +       if (IS_ERR(mux))
> +               dev_err(dev, "Mux clock registration failed\n");
> +
> +       return mux;
> +}
> +
> +static struct clk_regmap *
> +mmc_clkc_register_clk_with_parent(struct device *dev, struct regmap *map,
> +                                 char *suffix, const struct clk_hw *hw,
> +                                 unsigned long flags,
> +                                 const struct clk_ops *ops, void *data)
> +{
> +       struct clk_init_data init;
> +       struct clk_regmap *clk;
> +       const char *parent_name = clk_hw_get_name(hw);
> +
> +       init.ops = ops;
> +       init.flags = flags;
> +       init.parent_names = &parent_name;
> +       init.num_parents = 1;
> +
> +       clk = mmc_clkc_register_clk(dev, map, &init, suffix, data);
> +       if (IS_ERR(clk))
> +               dev_err(dev, "%s clock registration failed\n", suffix);
> +
> +       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 *clk, *core;
> +       struct meson_sclk_div_data *div_data;
> +
> +       /*cast to drop the const in match->data*/

Space after *, also why do we need to cast away const? The user of this
pointer passes it all the way down to mmc_clkc_register_clk() which
could take the data as const void pointer and decide to cast away const
there.

> +       data = (struct mmc_clkc_data *)of_device_get_match_data(dev);
> +       if (!data)
> +               return -ENODEV;
> +
> +       map = syscon_node_to_regmap(dev->of_node);
> +       if (IS_ERR(map)) {
> +               dev_err(dev, "could not find mmc clock controller\n");
> +               return PTR_ERR(map);
> +       }
> +
> +       onecell_data = devm_kzalloc(dev,
> +                                   struct_size(onecell_data, hws,
> +                                               MMC_MAX_CLKS),
> +                                   GFP_KERNEL);
> +       if (!onecell_data)
> +               return -ENOMEM;
> +
> +       clk = mmc_clkc_register_mux(dev, map);
> +       if (IS_ERR(clk))
> +               return PTR_ERR(clk);
> +
> +       div_data = devm_kzalloc(dev, sizeof(*div_data), GFP_KERNEL);
> +       if (!div_data)
> +               return -ENOMEM;
> +
> +       memcpy(div_data, &mmc_clkc_div_data, sizeof(*div_data));
> +       clk = mmc_clkc_register_clk_with_parent(dev, map, "div",
> +                                               &clk->hw,
> +                                               CLK_SET_RATE_PARENT,
> +                                               &meson_sclk_div_ops,
> +                                               div_data);
> +       if (IS_ERR(clk))
> +               return PTR_ERR(clk);
> +
> +       onecell_data->hws[CLKID_MMC_DIV] = &clk->hw;
> +       core = mmc_clkc_register_clk_with_parent(dev, map, "core",
> +                                                &clk->hw,
> +                                                CLK_SET_RATE_PARENT,
> +                                                &meson_clk_phase_ops,
> +                                                &mmc_clkc_core_phase);
> +       if (IS_ERR(core))
> +               return PTR_ERR(core);
> +
> +       onecell_data->hws[CLKID_MMC_PHASE_CORE] = &core->hw;
> +       clk = mmc_clkc_register_clk_with_parent(dev, map, "rx",
> +                                               &core->hw,  0,
> +                                               &meson_clk_phase_delay_ops,
> +                                               &data->rx);
> +       if (IS_ERR(clk))
> +               return PTR_ERR(clk);
> +
> +       onecell_data->hws[CLKID_MMC_PHASE_RX] = &clk->hw;
> +       clk = mmc_clkc_register_clk_with_parent(dev, map, "tx",
> +                                               &core->hw,  0,
> +                                               &meson_clk_phase_delay_ops,
> +                                               &data->tx);
> +       if (IS_ERR(clk))
> +               return PTR_ERR(clk);
> +
> +       onecell_data->hws[CLKID_MMC_PHASE_TX] = &clk->hw;
> +       onecell_data->num = MMC_MAX_CLKS;
> +       return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
> +                                          onecell_data);
> +}
> +
> +static struct platform_driver mmc_clkc_driver = {
> +       .probe          = mmc_clkc_probe,
> +       .driver         = {
> +               .name   = "meson-mmc-clkc",
> +               .of_match_table = of_match_ptr(mmc_clkc_match_table),
> +       },
> +};
> +
> +module_platform_driver(mmc_clkc_driver);
> +
> +MODULE_DESCRIPTION("Amlogic AXG MMC clock driver");
> +MODULE_AUTHOR("Jianxin Pan <jianxin.pan@amlogic.com>");
> +MODULE_LICENSE("GPL v2");
Liang Yang Jan. 14, 2022, 5:14 a.m. UTC | #2 
Hi Stephen,

On 2022/1/14 5:35, Stephen Boyd wrote:
> [ EXTERNAL EMAIL ]
> 
> Quoting Liang Yang (2022-01-13 03:57:45)
>> diff --git a/drivers/clk/meson/Kconfig b/drivers/clk/meson/Kconfig
>> index bb0f59eea366..3de6f3b24461 100644
>> --- a/drivers/clk/meson/Kconfig
>> +++ b/drivers/clk/meson/Kconfig
>> @@ -39,6 +39,20 @@ config COMMON_CLK_MESON_AO_CLKC
>>          select COMMON_CLK_MESON_REGMAP
>>          select RESET_CONTROLLER
>>   
>> +config COMMON_CLK_MMC_MESON
>> +       tristate "Meson MMC Sub Clock Controller Driver"
>> +       depends on ARCH_MESON || COMPILE_TEST
>> +       select MFD_SYSCON
>> +       select COMMON_CLK_AMLOGIC
>> +       select COMMON_CLK_MESON_PHASE
>> +       select COMMON_CLK_MESON_PHASE_DELAY
>> +       select COMMON_CLK_MESON_SCLK_DIV
>> +       help
>> +         Support for the MMC sub clock controller on
>> +         Amlogic Meson Platform, which includes S905 (GXBB, GXL),
>> +         A113D/X (AXG) devices . Say Y if you want this
> 
> s/devices /devices/
ok, i will fix it
> 
>> +         clock enabled.
>> +
>>   config COMMON_CLK_MESON_EE_CLKC
>>          tristate
>>          select COMMON_CLK_MESON_REGMAP
>> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
>> new file mode 100644
>> index 000000000000..f53977f61390
>> --- /dev/null
>> +++ b/drivers/clk/meson/mmc-clkc.c
>> @@ -0,0 +1,300 @@
>> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
>> +/*
>> + * Copyright (c) 2019 Amlogic, Inc. All rights reserved.
>> + */
>> +
>> +#include <linux/clk.h>
>> +#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,mmc-clkc.h>
>> +
>> +#include "sclk-div.h"
>> +#include "clk-phase-delay.h"
>> +#include "clk-regmap.h"
>> +#include "clk-phase.h"
>> +
>> +/* clock ID used by internal driver */
>> +
>> +#define SD_EMMC_CLOCK          0
>> +#define CLK_DELAY_STEP_PS_GX   200
>> +#define CLK_DELAY_STEP_PS_AXG  78
>> +#define MUX_CLK_NUM_PARENTS    2
>> +#define MMC_MAX_CLKS           4
>> +
>> +struct mmc_clkc_data {
>> +       struct meson_clk_phase_delay_data tx;
>> +       struct meson_clk_phase_delay_data rx;
>> +};
>> +
>> +static struct clk_regmap_mux_data mmc_clkc_mux_data = {
>> +       .offset = SD_EMMC_CLOCK,
>> +       .mask   = 0x3,
>> +       .shift  = 6,
>> +};
>> +
>> +static const struct meson_sclk_div_data mmc_clkc_div_data = {
>> +       .div = {
>> +               .reg_off = SD_EMMC_CLOCK,
>> +               .width   = 6,
>> +       },
>> +       .flags = MESON_SCLK_ONE_BASED,
>> +};
>> +
>> +static struct meson_clk_phase_data mmc_clkc_core_phase = {
>> +       .ph = {
>> +               .reg_off = SD_EMMC_CLOCK,
>> +               .shift   = 8,
>> +               .width   = 2,
>> +       }
>> +};
>> +
>> +static const struct mmc_clkc_data mmc_clkc_gx_data = {
>> +       .tx = {
>> +               .phase = {
>> +                       .reg_off = SD_EMMC_CLOCK,
>> +                       .shift   = 10,
>> +                       .width   = 2,
>> +               },
>> +               .delay = {
>> +                       .reg_off = SD_EMMC_CLOCK,
>> +                       .shift   = 16,
>> +                       .width   = 4,
>> +               },
>> +               .delay_step_ps = CLK_DELAY_STEP_PS_GX,
>> +       },
>> +       .rx = {
>> +               .phase = {
>> +                       .reg_off = SD_EMMC_CLOCK,
>> +                       .shift   = 12,
>> +                       .width   = 2,
>> +               },
>> +               .delay = {
>> +                       .reg_off = SD_EMMC_CLOCK,
>> +                       .shift   = 20,
>> +                       .width   = 4,
>> +               },
>> +               .delay_step_ps   = CLK_DELAY_STEP_PS_GX,
>> +       },
>> +};
>> +
>> +static const struct mmc_clkc_data mmc_clkc_axg_data = {
>> +       .tx = {
>> +               .phase = {
>> +                       .reg_off = SD_EMMC_CLOCK,
>> +                       .shift   = 10,
>> +                       .width   = 2,
>> +               },
>> +               .delay = {
>> +                       .reg_off = SD_EMMC_CLOCK,
>> +                       .shift   = 16,
>> +                       .width   = 6,
>> +               },
>> +               .delay_step_ps   = CLK_DELAY_STEP_PS_AXG,
>> +       },
>> +       .rx = {
>> +               .phase = {
>> +                       .reg_off = SD_EMMC_CLOCK,
>> +                       .shift   = 12,
>> +                       .width   = 2,
>> +               },
>> +               .delay = {
>> +                       .reg_off = SD_EMMC_CLOCK,
>> +                       .shift   = 22,
>> +                       .width   = 6,
>> +               },
>> +               .delay_step_ps   = CLK_DELAY_STEP_PS_AXG,
>> +       },
>> +};
>> +
>> +static const struct of_device_id mmc_clkc_match_table[] = {
>> +       {
>> +               .compatible     = "amlogic,gx-mmc-clkc",
>> +               .data           = &mmc_clkc_gx_data
>> +       },
>> +       {
>> +               .compatible     = "amlogic,axg-mmc-clkc",
>> +               .data           = &mmc_clkc_axg_data
>> +       },
>> +       {}
>> +};
>> +MODULE_DEVICE_TABLE(of, mmc_clkc_match_table);
>> +
>> +static struct clk_regmap *
>> +mmc_clkc_register_clk(struct device *dev, struct regmap *map,
>> +                     struct clk_init_data *init,
>> +                     const char *suffix, void *data)
>> +{
>> +       struct clk_regmap *clk;
>> +       char *name;
>> +       int ret;
>> +
>> +       clk = devm_kzalloc(dev, sizeof(*clk), GFP_KERNEL);
>> +       if (!clk)
>> +               return ERR_PTR(-ENOMEM);
>> +
>> +       name = kasprintf(GFP_KERNEL, "%s#%s", dev_name(dev), suffix);
>> +       if (!name)
>> +               return ERR_PTR(-ENOMEM);
>> +
>> +       init->name = name;
>> +       clk->map = map;
>> +       clk->data = data;
>> +       clk->hw.init = init;
>> +       ret = devm_clk_hw_register(dev, &clk->hw);
>> +       if (ret)
>> +               clk = ERR_PTR(ret);
>> +
>> +       kfree(name);
>> +       return clk;
>> +}
>> +
>> +static struct clk_regmap *mmc_clkc_register_mux(struct device *dev,
>> +                                               struct regmap *map)
>> +{
>> +       const char *parent_names[MUX_CLK_NUM_PARENTS];
>> +       struct clk_init_data init;
>> +       struct clk_regmap *mux;
>> +       struct clk *clk;
>> +       int i;
>> +
>> +       for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
>> +               char name[8];
>> +
>> +               snprintf(name, sizeof(name), "clkin%d", i);
>> +               clk = devm_clk_get(dev, name);
>> +               if (IS_ERR(clk)) {
>> +                       if (clk != ERR_PTR(-EPROBE_DEFER))
>> +                               dev_err(dev, "Missing clock %s\n", name);
> 
> Use dev_err_probe()?
ok
> 
>> +                       return ERR_CAST(clk);
>> +               }
>> +
>> +               parent_names[i] = __clk_get_name(clk);
> 
> Why can't we use clk_parent_data?

ok, i will try clk_parent_data.

> 
>> +       }
>> +
>> +       init.ops = &clk_regmap_mux_ops;
>> +       init.flags = CLK_SET_RATE_PARENT;
>> +       init.parent_names = parent_names;
>> +       init.num_parents = MUX_CLK_NUM_PARENTS;
>> +
>> +       mux = mmc_clkc_register_clk(dev, map, &init, "mux", &mmc_clkc_mux_data);
>> +       if (IS_ERR(mux))
>> +               dev_err(dev, "Mux clock registration failed\n");
>> +
>> +       return mux;
>> +}
>> +
>> +static struct clk_regmap *
>> +mmc_clkc_register_clk_with_parent(struct device *dev, struct regmap *map,
>> +                                 char *suffix, const struct clk_hw *hw,
>> +                                 unsigned long flags,
>> +                                 const struct clk_ops *ops, void *data)
>> +{
>> +       struct clk_init_data init;
>> +       struct clk_regmap *clk;
>> +       const char *parent_name = clk_hw_get_name(hw);
>> +
>> +       init.ops = ops;
>> +       init.flags = flags;
>> +       init.parent_names = &parent_name;
>> +       init.num_parents = 1;
>> +
>> +       clk = mmc_clkc_register_clk(dev, map, &init, suffix, data);
>> +       if (IS_ERR(clk))
>> +               dev_err(dev, "%s clock registration failed\n", suffix);
>> +
>> +       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 *clk, *core;
>> +       struct meson_sclk_div_data *div_data;
>> +
>> +       /*cast to drop the const in match->data*/
> 
> Space after *, also why do we need to cast away const? The user of this
> pointer passes it all the way down to mmc_clkc_register_clk() which
> could take the data as const void pointer and decide to cast away const
> there.

if use 'const' here, it will report a warning:
drivers/clk/meson/mmc-clkc.c:224:7: error: assignment discards ‘const’ 
qualifier from pointer targe
t type [-Werror=discarded-qualifiers] 

   data = (const struct mmc_clkc_data *)of_device_get_match_data(dev);

> 
>> +       data = (struct mmc_clkc_data *)of_device_get_match_data(dev);
>> +       if (!data)
>> +               return -ENODEV;
>> +
>> +       map = syscon_node_to_regmap(dev->of_node);
>> +       if (IS_ERR(map)) {
>> +               dev_err(dev, "could not find mmc clock controller\n");
>> +               return PTR_ERR(map);
>> +       }
>> +
>> +       onecell_data = devm_kzalloc(dev,
>> +                                   struct_size(onecell_data, hws,
>> +                                               MMC_MAX_CLKS),
>> +                                   GFP_KERNEL);
>> +       if (!onecell_data)
>> +               return -ENOMEM;
>> +
>> +       clk = mmc_clkc_register_mux(dev, map);
>> +       if (IS_ERR(clk))
>> +               return PTR_ERR(clk);
>> +
>> +       div_data = devm_kzalloc(dev, sizeof(*div_data), GFP_KERNEL);
>> +       if (!div_data)
>> +               return -ENOMEM;
>> +
>> +       memcpy(div_data, &mmc_clkc_div_data, sizeof(*div_data));
>> +       clk = mmc_clkc_register_clk_with_parent(dev, map, "div",
>> +                                               &clk->hw,
>> +                                               CLK_SET_RATE_PARENT,
>> +                                               &meson_sclk_div_ops,
>> +                                               div_data);
>> +       if (IS_ERR(clk))
>> +               return PTR_ERR(clk);
>> +
>> +       onecell_data->hws[CLKID_MMC_DIV] = &clk->hw;
>> +       core = mmc_clkc_register_clk_with_parent(dev, map, "core",
>> +                                                &clk->hw,
>> +                                                CLK_SET_RATE_PARENT,
>> +                                                &meson_clk_phase_ops,
>> +                                                &mmc_clkc_core_phase);
>> +       if (IS_ERR(core))
>> +               return PTR_ERR(core);
>> +
>> +       onecell_data->hws[CLKID_MMC_PHASE_CORE] = &core->hw;
>> +       clk = mmc_clkc_register_clk_with_parent(dev, map, "rx",
>> +                                               &core->hw,  0,
>> +                                               &meson_clk_phase_delay_ops,
>> +                                               &data->rx);
>> +       if (IS_ERR(clk))
>> +               return PTR_ERR(clk);
>> +
>> +       onecell_data->hws[CLKID_MMC_PHASE_RX] = &clk->hw;
>> +       clk = mmc_clkc_register_clk_with_parent(dev, map, "tx",
>> +                                               &core->hw,  0,
>> +                                               &meson_clk_phase_delay_ops,
>> +                                               &data->tx);
>> +       if (IS_ERR(clk))
>> +               return PTR_ERR(clk);
>> +
>> +       onecell_data->hws[CLKID_MMC_PHASE_TX] = &clk->hw;
>> +       onecell_data->num = MMC_MAX_CLKS;
>> +       return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
>> +                                          onecell_data);
>> +}
>> +
>> +static struct platform_driver mmc_clkc_driver = {
>> +       .probe          = mmc_clkc_probe,
>> +       .driver         = {
>> +               .name   = "meson-mmc-clkc",
>> +               .of_match_table = of_match_ptr(mmc_clkc_match_table),
>> +       },
>> +};
>> +
>> +module_platform_driver(mmc_clkc_driver);
>> +
>> +MODULE_DESCRIPTION("Amlogic AXG MMC clock driver");
>> +MODULE_AUTHOR("Jianxin Pan <jianxin.pan@amlogic.com>");
>> +MODULE_LICENSE("GPL v2");
> 
> .
Stephen Boyd Jan. 14, 2022, 11:01 p.m. UTC | #3 
Quoting Liang Yang (2022-01-13 21:14:46)
> On 2022/1/14 5:35, Stephen Boyd wrote:
> > Quoting Liang Yang (2022-01-13 03:57:45)
> >> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
> >> new file mode 100644
> >> index 000000000000..f53977f61390
> >> --- /dev/null
> >> +++ b/drivers/clk/meson/mmc-clkc.c
> >> @@ -0,0 +1,300 @@
[..]
> >> +
> >> +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 *clk, *core;
> >> +       struct meson_sclk_div_data *div_data;
> >> +
> >> +       /*cast to drop the const in match->data*/
> > 
> > Space after *, also why do we need to cast away const? The user of this
> > pointer passes it all the way down to mmc_clkc_register_clk() which
> > could take the data as const void pointer and decide to cast away const
> > there.
> 
> if use 'const' here, it will report a warning:
> drivers/clk/meson/mmc-clkc.c:224:7: error: assignment discards ‘const’ 
> qualifier from pointer targe
> t type [-Werror=discarded-qualifiers] 
> 
>    data = (const struct mmc_clkc_data *)of_device_get_match_data(dev);

Of course. The type declaration up above needs const added to it.
Liang Yang Jan. 17, 2022, 6:24 a.m. UTC | #4 
On 2022/1/15 7:01, Stephen Boyd wrote:
> [ EXTERNAL EMAIL ]
> 
> Quoting Liang Yang (2022-01-13 21:14:46)
>> On 2022/1/14 5:35, Stephen Boyd wrote:
>>> Quoting Liang Yang (2022-01-13 03:57:45)
>>>> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
>>>> new file mode 100644
>>>> index 000000000000..f53977f61390
>>>> --- /dev/null
>>>> +++ b/drivers/clk/meson/mmc-clkc.c
>>>> @@ -0,0 +1,300 @@
> [..]
>>>> +
>>>> +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 *clk, *core;
>>>> +       struct meson_sclk_div_data *div_data;
>>>> +
>>>> +       /*cast to drop the const in match->data*/
>>>
>>> Space after *, also why do we need to cast away const? The user of this
>>> pointer passes it all the way down to mmc_clkc_register_clk() which
>>> could take the data as const void pointer and decide to cast away const
>>> there.
>>
>> if use 'const' here, it  will report a warning:
>> drivers/clk/meson/mmc-clkc.c:224:7: error: assignment discards ‘const’
>> qualifier from pointer targe
>> t type [-Werror=discarded-qualifiers]
>>
>>     data = (const struct mmc_clkc_data *)of_device_get_match_data(dev);
> 
> Of course. The type declaration up above needs const added to it.The parm of mmc_clkc_register_clk_with_parent(...., void *data) does not 
have 'const', so make the type declaration cause a further 'const' cast 
warning. Could i copy these infos just like below:

struct mmc_clkc_data *data_clkc;
......
data = of_device_get_match_data(dev);
data_clkc = devm_kmalloc(dev, sizeof(*data_clkc), GFP_KERNEL);
memcpy(data_clkc, data, sizeof(*data_clkc));
......
clk = mmc_clkc_register_clk_with_parent(...., &data_clkc->rx);

> 
> .
Stephen Boyd Jan. 19, 2022, 2:22 a.m. UTC | #5 
Quoting Liang Yang (2022-01-16 22:24:28)
> 
> 
> On 2022/1/15 7:01, Stephen Boyd wrote:
> > [ EXTERNAL EMAIL ]
> > 
> > Quoting Liang Yang (2022-01-13 21:14:46)
> >> On 2022/1/14 5:35, Stephen Boyd wrote:
> >>> Quoting Liang Yang (2022-01-13 03:57:45)
> >>>> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
> >>>> new file mode 100644
> >>>> index 000000000000..f53977f61390
> >>>> --- /dev/null
> >>>> +++ b/drivers/clk/meson/mmc-clkc.c
> >>>> @@ -0,0 +1,300 @@
> > [..]
> >>>> +
> >>>> +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 *clk, *core;
> >>>> +       struct meson_sclk_div_data *div_data;
> >>>> +
> >>>> +       /*cast to drop the const in match->data*/
> >>>
> >>> Space after *, also why do we need to cast away const? The user of this
> >>> pointer passes it all the way down to mmc_clkc_register_clk() which
> >>> could take the data as const void pointer and decide to cast away const
> >>> there.
> >>
> >> if use 'const' here, it  will report a warning:
> >> drivers/clk/meson/mmc-clkc.c:224:7: error: assignment discards ‘const’
> >> qualifier from pointer targe
> >> t type [-Werror=discarded-qualifiers]
> >>
> >>     data = (const struct mmc_clkc_data *)of_device_get_match_data(dev);
> > 
> > Of course. The type declaration up above needs const added to it.The parm of mmc_clkc_register_clk_with_parent(...., void *data) does not 
> have 'const', so make the type declaration cause a further 'const' cast 
> warning. Could i copy these infos just like below:

Why can't you push const down to the function that really cares to
remove const?
Liang Yang Jan. 19, 2022, 2:55 a.m. UTC | #6 
Hi Stephen,

On 2022/1/19 10:22, Stephen Boyd wrote:
> [ EXTERNAL EMAIL ]
> 
> Quoting Liang Yang (2022-01-16 22:24:28)
>>
>>
>> On 2022/1/15 7:01, Stephen Boyd wrote:
>>> [ EXTERNAL EMAIL ]
>>>
>>> Quoting Liang Yang (2022-01-13 21:14:46)
>>>> On 2022/1/14 5:35, Stephen Boyd wrote:
>>>>> Quoting Liang Yang (2022-01-13 03:57:45)
>>>>>> diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
>>>>>> new file mode 100644
>>>>>> index 000000000000..f53977f61390
>>>>>> --- /dev/null
>>>>>> +++ b/drivers/clk/meson/mmc-clkc.c
>>>>>> @@ -0,0 +1,300 @@
>>> [..]
>>>>>> +
>>>>>> +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 *clk, *core;
>>>>>> +       struct meson_sclk_div_data *div_data;
>>>>>> +
>>>>>> +       /*cast to drop the const in match->data*/
>>>>>
>>>>> Space after *, also why do we need to cast away const? The user of this
>>>>> pointer passes it all the way down to mmc_clkc_register_clk() which
>>>>> could take the data as const void pointer and decide to cast away const
>>>>> there.
>>>>
>>>> if use 'const' here, it  will report a warning:
>>>> drivers/clk/meson/mmc-clkc.c:224:7: error: assignment discards ‘const’
>>>> qualifier from pointer targe
>>>> t type [-Werror=discarded-qualifiers]
>>>>
>>>>      data = (const struct mmc_clkc_data *)of_device_get_match_data(dev);
>>>
>>> Of course. The type declaration up above needs const added to it.The parm of mmc_clkc_register_clk_with_parent(...., void *data) does not
>> have 'const', so make the type declaration cause a further 'const' cast
>> warning. Could i copy these infos just like below:
> 
> Why can't you push const down to the function that really cares to
> remove const?
em, it is really ok to me. i will fix it next version.
> 
> .
diff mbox series

Patch

diff --git a/drivers/clk/meson/Kconfig b/drivers/clk/meson/Kconfig
index bb0f59eea366..3de6f3b24461 100644
--- a/drivers/clk/meson/Kconfig
+++ b/drivers/clk/meson/Kconfig
@@ -39,6 +39,20 @@  config COMMON_CLK_MESON_AO_CLKC
 	select COMMON_CLK_MESON_REGMAP
 	select RESET_CONTROLLER
 
+config COMMON_CLK_MMC_MESON
+	tristate "Meson MMC Sub Clock Controller Driver"
+	depends on ARCH_MESON || COMPILE_TEST
+	select MFD_SYSCON
+	select COMMON_CLK_AMLOGIC
+	select COMMON_CLK_MESON_PHASE
+	select COMMON_CLK_MESON_PHASE_DELAY
+	select COMMON_CLK_MESON_SCLK_DIV
+	help
+	  Support for the MMC sub clock controller on
+	  Amlogic Meson Platform, which includes S905 (GXBB, GXL),
+	  A113D/X (AXG) devices . Say Y if you want this
+	  clock enabled.
+
 config COMMON_CLK_MESON_EE_CLKC
 	tristate
 	select COMMON_CLK_MESON_REGMAP
diff --git a/drivers/clk/meson/Makefile b/drivers/clk/meson/Makefile
index c450f38d3801..f7a94a33e789 100644
--- a/drivers/clk/meson/Makefile
+++ b/drivers/clk/meson/Makefile
@@ -17,6 +17,7 @@  obj-$(CONFIG_COMMON_CLK_MESON_PHASE_DELAY) += clk-phase-delay.o
 
 obj-$(CONFIG_COMMON_CLK_AXG) += axg.o axg-aoclk.o
 obj-$(CONFIG_COMMON_CLK_AXG_AUDIO) += axg-audio.o
+obj-$(CONFIG_COMMON_CLK_MMC_MESON) += mmc-clkc.o
 obj-$(CONFIG_COMMON_CLK_GXBB) += gxbb.o gxbb-aoclk.o
 obj-$(CONFIG_COMMON_CLK_G12A) += g12a.o g12a-aoclk.o
 obj-$(CONFIG_COMMON_CLK_MESON8B) += meson8b.o meson8-ddr.o
diff --git a/drivers/clk/meson/mmc-clkc.c b/drivers/clk/meson/mmc-clkc.c
new file mode 100644
index 000000000000..f53977f61390
--- /dev/null
+++ b/drivers/clk/meson/mmc-clkc.c
@@ -0,0 +1,300 @@ 
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (c) 2019 Amlogic, Inc. All rights reserved.
+ */
+
+#include <linux/clk.h>
+#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,mmc-clkc.h>
+
+#include "sclk-div.h"
+#include "clk-phase-delay.h"
+#include "clk-regmap.h"
+#include "clk-phase.h"
+
+/* clock ID used by internal driver */
+
+#define SD_EMMC_CLOCK		0
+#define CLK_DELAY_STEP_PS_GX	200
+#define CLK_DELAY_STEP_PS_AXG	78
+#define MUX_CLK_NUM_PARENTS	2
+#define MMC_MAX_CLKS		4
+
+struct mmc_clkc_data {
+	struct meson_clk_phase_delay_data tx;
+	struct meson_clk_phase_delay_data rx;
+};
+
+static struct clk_regmap_mux_data mmc_clkc_mux_data = {
+	.offset = SD_EMMC_CLOCK,
+	.mask   = 0x3,
+	.shift  = 6,
+};
+
+static const struct meson_sclk_div_data mmc_clkc_div_data = {
+	.div = {
+		.reg_off = SD_EMMC_CLOCK,
+		.width   = 6,
+	},
+	.flags = MESON_SCLK_ONE_BASED,
+};
+
+static struct meson_clk_phase_data mmc_clkc_core_phase = {
+	.ph = {
+		.reg_off = SD_EMMC_CLOCK,
+		.shift   = 8,
+		.width   = 2,
+	}
+};
+
+static const struct mmc_clkc_data mmc_clkc_gx_data = {
+	.tx = {
+		.phase = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 10,
+			.width   = 2,
+		},
+		.delay = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 16,
+			.width   = 4,
+		},
+		.delay_step_ps = CLK_DELAY_STEP_PS_GX,
+	},
+	.rx = {
+		.phase = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 12,
+			.width   = 2,
+		},
+		.delay = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 20,
+			.width   = 4,
+		},
+		.delay_step_ps   = CLK_DELAY_STEP_PS_GX,
+	},
+};
+
+static const struct mmc_clkc_data mmc_clkc_axg_data = {
+	.tx = {
+		.phase = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 10,
+			.width   = 2,
+		},
+		.delay = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 16,
+			.width   = 6,
+		},
+		.delay_step_ps   = CLK_DELAY_STEP_PS_AXG,
+	},
+	.rx = {
+		.phase = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 12,
+			.width   = 2,
+		},
+		.delay = {
+			.reg_off = SD_EMMC_CLOCK,
+			.shift   = 22,
+			.width   = 6,
+		},
+		.delay_step_ps   = CLK_DELAY_STEP_PS_AXG,
+	},
+};
+
+static const struct of_device_id mmc_clkc_match_table[] = {
+	{
+		.compatible	= "amlogic,gx-mmc-clkc",
+		.data		= &mmc_clkc_gx_data
+	},
+	{
+		.compatible	= "amlogic,axg-mmc-clkc",
+		.data		= &mmc_clkc_axg_data
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, mmc_clkc_match_table);
+
+static struct clk_regmap *
+mmc_clkc_register_clk(struct device *dev, struct regmap *map,
+		      struct clk_init_data *init,
+		      const char *suffix, void *data)
+{
+	struct clk_regmap *clk;
+	char *name;
+	int ret;
+
+	clk = devm_kzalloc(dev, sizeof(*clk), GFP_KERNEL);
+	if (!clk)
+		return ERR_PTR(-ENOMEM);
+
+	name = kasprintf(GFP_KERNEL, "%s#%s", dev_name(dev), suffix);
+	if (!name)
+		return ERR_PTR(-ENOMEM);
+
+	init->name = name;
+	clk->map = map;
+	clk->data = data;
+	clk->hw.init = init;
+	ret = devm_clk_hw_register(dev, &clk->hw);
+	if (ret)
+		clk = ERR_PTR(ret);
+
+	kfree(name);
+	return clk;
+}
+
+static struct clk_regmap *mmc_clkc_register_mux(struct device *dev,
+						struct regmap *map)
+{
+	const char *parent_names[MUX_CLK_NUM_PARENTS];
+	struct clk_init_data init;
+	struct clk_regmap *mux;
+	struct clk *clk;
+	int i;
+
+	for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
+		char name[8];
+
+		snprintf(name, sizeof(name), "clkin%d", i);
+		clk = devm_clk_get(dev, name);
+		if (IS_ERR(clk)) {
+			if (clk != ERR_PTR(-EPROBE_DEFER))
+				dev_err(dev, "Missing clock %s\n", name);
+			return ERR_CAST(clk);
+		}
+
+		parent_names[i] = __clk_get_name(clk);
+	}
+
+	init.ops = &clk_regmap_mux_ops;
+	init.flags = CLK_SET_RATE_PARENT;
+	init.parent_names = parent_names;
+	init.num_parents = MUX_CLK_NUM_PARENTS;
+
+	mux = mmc_clkc_register_clk(dev, map, &init, "mux", &mmc_clkc_mux_data);
+	if (IS_ERR(mux))
+		dev_err(dev, "Mux clock registration failed\n");
+
+	return mux;
+}
+
+static struct clk_regmap *
+mmc_clkc_register_clk_with_parent(struct device *dev, struct regmap *map,
+				  char *suffix, const struct clk_hw *hw,
+				  unsigned long flags,
+				  const struct clk_ops *ops, void *data)
+{
+	struct clk_init_data init;
+	struct clk_regmap *clk;
+	const char *parent_name = clk_hw_get_name(hw);
+
+	init.ops = ops;
+	init.flags = flags;
+	init.parent_names = &parent_name;
+	init.num_parents = 1;
+
+	clk = mmc_clkc_register_clk(dev, map, &init, suffix, data);
+	if (IS_ERR(clk))
+		dev_err(dev, "%s clock registration failed\n", suffix);
+
+	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 *clk, *core;
+	struct meson_sclk_div_data *div_data;
+
+	/*cast to drop the const in match->data*/
+	data = (struct mmc_clkc_data *)of_device_get_match_data(dev);
+	if (!data)
+		return -ENODEV;
+
+	map = syscon_node_to_regmap(dev->of_node);
+	if (IS_ERR(map)) {
+		dev_err(dev, "could not find mmc clock controller\n");
+		return PTR_ERR(map);
+	}
+
+	onecell_data = devm_kzalloc(dev,
+				    struct_size(onecell_data, hws,
+						MMC_MAX_CLKS),
+				    GFP_KERNEL);
+	if (!onecell_data)
+		return -ENOMEM;
+
+	clk = mmc_clkc_register_mux(dev, map);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	div_data = devm_kzalloc(dev, sizeof(*div_data), GFP_KERNEL);
+	if (!div_data)
+		return -ENOMEM;
+
+	memcpy(div_data, &mmc_clkc_div_data, sizeof(*div_data));
+	clk = mmc_clkc_register_clk_with_parent(dev, map, "div",
+						&clk->hw,
+						CLK_SET_RATE_PARENT,
+						&meson_sclk_div_ops,
+						div_data);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	onecell_data->hws[CLKID_MMC_DIV] = &clk->hw;
+	core = mmc_clkc_register_clk_with_parent(dev, map, "core",
+						 &clk->hw,
+						 CLK_SET_RATE_PARENT,
+						 &meson_clk_phase_ops,
+						 &mmc_clkc_core_phase);
+	if (IS_ERR(core))
+		return PTR_ERR(core);
+
+	onecell_data->hws[CLKID_MMC_PHASE_CORE] = &core->hw;
+	clk = mmc_clkc_register_clk_with_parent(dev, map, "rx",
+						&core->hw,  0,
+						&meson_clk_phase_delay_ops,
+						&data->rx);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	onecell_data->hws[CLKID_MMC_PHASE_RX] = &clk->hw;
+	clk = mmc_clkc_register_clk_with_parent(dev, map, "tx",
+						&core->hw,  0,
+						&meson_clk_phase_delay_ops,
+						&data->tx);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	onecell_data->hws[CLKID_MMC_PHASE_TX] = &clk->hw;
+	onecell_data->num = MMC_MAX_CLKS;
+	return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
+					   onecell_data);
+}
+
+static struct platform_driver mmc_clkc_driver = {
+	.probe		= mmc_clkc_probe,
+	.driver		= {
+		.name	= "meson-mmc-clkc",
+		.of_match_table = of_match_ptr(mmc_clkc_match_table),
+	},
+};
+
+module_platform_driver(mmc_clkc_driver);
+
+MODULE_DESCRIPTION("Amlogic AXG MMC clock driver");
+MODULE_AUTHOR("Jianxin Pan <jianxin.pan@amlogic.com>");
+MODULE_LICENSE("GPL v2");