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

From: Stephen Boyd
Date: Thu Jan 13 2022 - 16:35:18 EST

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In reply to: Liang Yang: "[PATCH v9 4/4] clk: meson: add sub MMC clock controller driver"
Next in thread: Liang Yang: "Re: [PATCH v9 4/4] clk: meson: add sub MMC clock controller driver"
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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@xxxxxxxxxxx>");
> +MODULE_LICENSE("GPL v2");

Next message: Reinette Chatre: "Re: [PATCH 05/25] x86/sgx: Introduce runtime protection bits"
Previous message: kernel test robot: "[intel-tdx:tdx/guest-rebased 118/133] kernel/dma/swiotlb.c:388:15: warning: cast to 'struct io_tlb_area *' from smaller integer type 'int'"
In reply to: Liang Yang: "[PATCH v9 4/4] clk: meson: add sub MMC clock controller driver"
Next in thread: Liang Yang: "Re: [PATCH v9 4/4] clk: meson: add sub MMC clock controller driver"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]