Re: [PATCH v4 07/10] clk: starfive: Add StarFive JH7110 Video-Output clock driver

From: Stephen Boyd
Date: Tue Apr 11 2023 - 14:33:53 EST


Quoting Xingyu Wu (2023-04-11 06:55:55)
> diff --git a/drivers/clk/starfive/clk-starfive-jh7110-vout.c b/drivers/clk/starfive/clk-starfive-jh7110-vout.c
> new file mode 100644
> index 000000000000..4c6f5ae198cf
> --- /dev/null
> +++ b/drivers/clk/starfive/clk-starfive-jh7110-vout.c
> @@ -0,0 +1,239 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * StarFive JH7110 Video-Output Clock Driver
> + *
> + * Copyright (C) 2022 StarFive Technology Co., Ltd.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/clk-provider.h>
> +#include <linux/io.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/reset.h>

Include module.h, device.h, and kernel.h for things like ERR_PTR().
Probably need to include a reset header as well for reset APIs.

> +
> +#include <dt-bindings/clock/starfive,jh7110-crg.h>
> +
> +#include "clk-starfive-jh7110.h"
> +
> +/* external clocks */
> +#define JH7110_VOUTCLK_VOUT_SRC (JH7110_VOUTCLK_END + 0)
> +#define JH7110_VOUTCLK_VOUT_TOP_AHB (JH7110_VOUTCLK_END + 1)
> +#define JH7110_VOUTCLK_VOUT_TOP_AXI (JH7110_VOUTCLK_END + 2)
> +#define JH7110_VOUTCLK_VOUT_TOP_HDMITX0_MCLK (JH7110_VOUTCLK_END + 3)
> +#define JH7110_VOUTCLK_I2STX0_BCLK (JH7110_VOUTCLK_END + 4)
> +#define JH7110_VOUTCLK_HDMITX0_PIXELCLK (JH7110_VOUTCLK_END + 5)
> +#define JH7110_VOUTCLK_EXT_END (JH7110_VOUTCLK_END + 6)
> +
> +/* VOUT domian clocks */
> +struct vout_top_crg {
> + struct clk_bulk_data *top_clks;
> + int top_clks_num;

size_t?

> + void __iomem *base;
> +};
> +
> +static struct clk_bulk_data jh7110_vout_top_clks[] = {
> + { .id = "vout_src" },
> + { .id = "vout_top_ahb" }
> +};
> +
> +static const struct jh71x0_clk_data jh7110_voutclk_data[] = {
> + /* divider */
> + JH71X0__DIV(JH7110_VOUTCLK_APB, "apb", 8, JH7110_VOUTCLK_VOUT_TOP_AHB),
> + JH71X0__DIV(JH7110_VOUTCLK_DC8200_PIX, "dc8200_pix", 63, JH7110_VOUTCLK_VOUT_SRC),
> + JH71X0__DIV(JH7110_VOUTCLK_DSI_SYS, "dsi_sys", 31, JH7110_VOUTCLK_VOUT_SRC),
> + JH71X0__DIV(JH7110_VOUTCLK_TX_ESC, "tx_esc", 31, JH7110_VOUTCLK_VOUT_TOP_AHB),
> + /* dc8200 */
> + JH71X0_GATE(JH7110_VOUTCLK_DC8200_AXI, "dc8200_axi", 0, JH7110_VOUTCLK_VOUT_TOP_AXI),
> + JH71X0_GATE(JH7110_VOUTCLK_DC8200_CORE, "dc8200_core", 0, JH7110_VOUTCLK_VOUT_TOP_AXI),
> + JH71X0_GATE(JH7110_VOUTCLK_DC8200_AHB, "dc8200_ahb", 0, JH7110_VOUTCLK_VOUT_TOP_AHB),
> + JH71X0_GMUX(JH7110_VOUTCLK_DC8200_PIX0, "dc8200_pix0", 0, 2,
> + JH7110_VOUTCLK_DC8200_PIX,
> + JH7110_VOUTCLK_HDMITX0_PIXELCLK),
> + JH71X0_GMUX(JH7110_VOUTCLK_DC8200_PIX1, "dc8200_pix1", 0, 2,
> + JH7110_VOUTCLK_DC8200_PIX,
> + JH7110_VOUTCLK_HDMITX0_PIXELCLK),
> + /* LCD */
> + JH71X0_GMUX(JH7110_VOUTCLK_DOM_VOUT_TOP_LCD, "dom_vout_top_lcd", 0, 2,
> + JH7110_VOUTCLK_DC8200_PIX0,
> + JH7110_VOUTCLK_DC8200_PIX1),
> + /* dsiTx */
> + JH71X0_GATE(JH7110_VOUTCLK_DSITX_APB, "dsiTx_apb", 0, JH7110_VOUTCLK_DSI_SYS),
> + JH71X0_GATE(JH7110_VOUTCLK_DSITX_SYS, "dsiTx_sys", 0, JH7110_VOUTCLK_DSI_SYS),
> + JH71X0_GMUX(JH7110_VOUTCLK_DSITX_DPI, "dsiTx_dpi", 0, 2,
> + JH7110_VOUTCLK_DC8200_PIX,
> + JH7110_VOUTCLK_HDMITX0_PIXELCLK),
> + JH71X0_GATE(JH7110_VOUTCLK_DSITX_TXESC, "dsiTx_txesc", 0, JH7110_VOUTCLK_TX_ESC),
> + /* mipitx DPHY */
> + JH71X0_GATE(JH7110_VOUTCLK_MIPITX_DPHY_TXESC, "mipitx_dphy_txesc", 0,
> + JH7110_VOUTCLK_TX_ESC),
> + /* hdmi */
> + JH71X0_GATE(JH7110_VOUTCLK_HDMI_TX_MCLK, "hdmi_tx_mclk", 0,
> + JH7110_VOUTCLK_VOUT_TOP_HDMITX0_MCLK),
> + JH71X0_GATE(JH7110_VOUTCLK_HDMI_TX_BCLK, "hdmi_tx_bclk", 0,
> + JH7110_VOUTCLK_I2STX0_BCLK),
> + JH71X0_GATE(JH7110_VOUTCLK_HDMI_TX_SYS, "hdmi_tx_sys", 0, JH7110_VOUTCLK_APB),
> +};
> +
> +static struct vout_top_crg *top_crg_from(void __iomem **base)
> +{
> + return container_of(base, struct vout_top_crg, base);
> +}
> +
> +static int jh7110_vout_top_crg_init(struct jh71x0_clk_priv *priv, struct vout_top_crg *top)
> +{
> + struct reset_control *top_rst;
> + int ret;
> +
> + top->top_clks = jh7110_vout_top_clks;
> + top->top_clks_num = ARRAY_SIZE(jh7110_vout_top_clks);
> + ret = devm_clk_bulk_get(priv->dev, top->top_clks_num, top->top_clks);
> + if (ret)
> + return dev_err_probe(priv->dev, ret, "failed to get top clocks\n");
> +
> + /* The reset should be shared and other Vout modules will use its. */
> + top_rst = devm_reset_control_get_shared(priv->dev, NULL);
> + if (IS_ERR(top_rst))
> + return dev_err_probe(priv->dev, PTR_ERR(top_rst), "failed to get top reset\n");
> +
> + ret = clk_bulk_prepare_enable(top->top_clks_num, top->top_clks);
> + if (ret)
> + return dev_err_probe(priv->dev, ret, "failed to enable top clocks\n");
> +
> + return reset_control_deassert(top_rst);
> +}
> +
> +static struct clk_hw *jh7110_voutclk_get(struct of_phandle_args *clkspec, void *data)
> +{
> + struct jh71x0_clk_priv *priv = data;
> + unsigned int idx = clkspec->args[0];
> +
> + if (idx < JH7110_VOUTCLK_END)
> + return &priv->reg[idx].hw;
> +
> + return ERR_PTR(-EINVAL);
> +}
> +
> +static int jh7110_voutcrg_probe(struct platform_device *pdev)
> +{
> + struct jh71x0_clk_priv *priv;
> + struct vout_top_crg *top;
> + unsigned int idx;
> + int ret;
> +
> + priv = devm_kzalloc(&pdev->dev,
> + struct_size(priv, reg, JH7110_VOUTCLK_END),
> + GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + top = devm_kzalloc(&pdev->dev, sizeof(*top), GFP_KERNEL);
> + if (!top)
> + return -ENOMEM;
> +
> + spin_lock_init(&priv->rmw_lock);
> + priv->dev = &pdev->dev;
> + priv->base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(priv->base))
> + return PTR_ERR(priv->base);
> +
> + pm_runtime_enable(priv->dev);

Use devm_pm_runtime_enable()?

> + ret = pm_runtime_get_sync(priv->dev);

And use pm_runtime_resume_and_get() here?

> + if (ret < 0)
> + return dev_err_probe(priv->dev, ret, "failed to turn on power\n");
> +
> + ret = jh7110_vout_top_crg_init(priv, top);
> + if (ret)
> + goto err_clk;
> +
> + top->base = priv->base;
> + dev_set_drvdata(priv->dev, (void *)(&top->base));

See comment later about setting this to 'top' instead. Casting away
iomem markings is not good hygiene.

> +
> + for (idx = 0; idx < JH7110_VOUTCLK_END; idx++) {
> + u32 max = jh7110_voutclk_data[idx].max;
> + struct clk_parent_data parents[4] = {};
> + struct clk_init_data init = {
> + .name = jh7110_voutclk_data[idx].name,
> + .ops = starfive_jh71x0_clk_ops(max),
> + .parent_data = parents,
> + .num_parents =
> + ((max & JH71X0_CLK_MUX_MASK) >> JH71X0_CLK_MUX_SHIFT) + 1,
> + .flags = jh7110_voutclk_data[idx].flags,
> + };
> + struct jh71x0_clk *clk = &priv->reg[idx];
> + unsigned int i;
> + const char *fw_name[JH7110_VOUTCLK_EXT_END - JH7110_VOUTCLK_END] = {
> + "vout_src",
> + "vout_top_ahb",
> + "vout_top_axi",
> + "vout_top_hdmitx0_mclk",
> + "i2stx0_bclk",
> + "hdmitx0_pixelclk"
> + };
> +
> + for (i = 0; i < init.num_parents; i++) {
> + unsigned int pidx = jh7110_voutclk_data[idx].parents[i];
> +
> + if (pidx < JH7110_VOUTCLK_END)
> + parents[i].hw = &priv->reg[pidx].hw;
> + else if (pidx < JH7110_VOUTCLK_EXT_END)
> + parents[i].fw_name = fw_name[pidx - JH7110_VOUTCLK_END];

Can you use .index instead?

> + }
> +
> + clk->hw.init = &init;
> + clk->idx = idx;
> + clk->max_div = max & JH71X0_CLK_DIV_MASK;
> +
> + ret = devm_clk_hw_register(&pdev->dev, &clk->hw);
> + if (ret)
> + goto err_exit;
> + }
> +
> + ret = devm_of_clk_add_hw_provider(&pdev->dev, jh7110_voutclk_get, priv);
> + if (ret)
> + goto err_exit;
> +
> + ret = jh7110_reset_controller_register(priv, "rst-vout", 4);
> + if (ret)
> + goto err_exit;
> +
> + return 0;
> +
> +err_exit:
> + clk_bulk_disable_unprepare(top->top_clks_num, top->top_clks);
> +err_clk:
> + pm_runtime_put_sync(priv->dev);
> + pm_runtime_disable(priv->dev);
> + return ret;
> +}
> +
> +static int jh7110_voutcrg_remove(struct platform_device *pdev)
> +{
> + void __iomem **base = dev_get_drvdata(&pdev->dev);

Why not set the driver data to be vout_top_crg?

> + struct vout_top_crg *top = top_crg_from(base);

And get rid of this top_crg_from() API?

> +
> + clk_bulk_disable_unprepare(top->top_clks_num, top->top_clks);
> + pm_runtime_disable(&pdev->dev);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id jh7110_voutcrg_match[] = {
> + { .compatible = "starfive,jh7110-voutcrg" },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, jh7110_voutcrg_match);
> +
> +static struct platform_driver jh7110_voutcrg_driver = {
> + .probe = jh7110_voutcrg_probe,
> + .remove = jh7110_voutcrg_remove,

Use remove_new please.