Re: [PATCH v7 4/9] clk: mediatek: Add MT2701 clock support

Stephen Boyd
2016-05-06T23:11:56Z

On 04/14, James Liao wrote:
> diff --git a/drivers/clk/mediatek/clk-mt2701.c b/drivers/clk/mediatek/clk-mt2701.c
> new file mode 100644
> index 0000000..b4db141
> --- /dev/null
> +++ b/drivers/clk/mediatek/clk-mt2701.c
> +static void __init mtk_infrasys_init(struct device_node *node)
> +{
> + struct clk_onecell_data *clk_data;
> + int r;
> +
> + clk_data = mtk_alloc_clk_data(CLK_INFRA_NR);
> +
> + mtk_clk_register_gates(node, infra_clks, ARRAY_SIZE(infra_clks),
> + clk_data);
> + mtk_clk_register_factors(infra_fixed_divs, ARRAY_SIZE(infra_fixed_divs),
> + clk_data);
> +
> + r = of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
> + if (r)
> + pr_err("%s(): could not register clock provider: %d\n",
> + __func__, r);
> +}
> +CLK_OF_DECLARE(mtk_infrasys, "mediatek,mt2701-infracfg", mtk_infrasys_init);

I'm still lost on the usage of CLK_OF_DECLARE here. What part of
these clk controllers needs to be registered to make the timer
work?

> + GATE_DISP1(CLK_MM_DPI_DIGL, "mm_dpi_digl", "dpi0_sel", 2),
> + GATE_DISP1(CLK_MM_DPI_ENGINE, "mm_dpi_eng", "mm_sel", 3),
> + GATE_DISP1(CLK_MM_DPI1_DIGL, "mm_dpi1_digl", "dpi1_sel", 4),
> + GATE_DISP1(CLK_MM_DPI1_ENGINE, "mm_dpi1_eng", "mm_sel", 5),
> + GATE_DISP1(CLK_MM_TVE_OUTPUT, "mm_tve_output", "tve_sel", 6),
> + GATE_DISP1(CLK_MM_TVE_INPUT, "mm_tve_input", "dpi0_sel", 7),
> + GATE_DISP1(CLK_MM_HDMI_PIXEL, "mm_hdmi_pixel", "dpi1_sel", 8),
> + GATE_DISP1(CLK_MM_HDMI_PLL, "mm_hdmi_pll", "hdmi_sel", 9),
> + GATE_DISP1(CLK_MM_HDMI_AUDIO, "mm_hdmi_audio", "apll_sel", 10),
> + GATE_DISP1(CLK_MM_HDMI_SPDIF, "mm_hdmi_spdif", "apll_sel", 11),
> + GATE_DISP1(CLK_MM_TVE_FMM, "mm_tve_fmm", "mm_sel", 14),
> +};

I also don't understand why we don't have different files and
drivers for all these different clock controllers? They all have
a similar probe structure, sure, but otherwise these are
different devices with different clks for them. The whole #ifdef
thing in the later patch would go away too.

> + GATE_BDP1(CLK_BDP_BRG_RT_B, "brg_rt_bclk", "mm_sel", 12),
> + GATE_BDP1(CLK_BDP_BRG_RT_DRAM, "brg_rt_dram", "mm_sel", 13),
> + GATE_BDP1(CLK_BDP_LARBRT_DRAM, "larbrt_dram", "mm_sel", 14),
> + GATE_BDP1(CLK_BDP_TMDS_SYN, "tmds_syn", "hdmi_0_pll340m", 15),
> + GATE_BDP1(CLK_BDP_HDMI_MON, "hdmi_mon", "hdmi_0_pll340m", 16),
> +};
> +
> +static void __init mtk_bdpsys_init(struct device_node *node)

Shouldn't be __init because it's driver probe path.

> +{
> + struct clk_onecell_data *clk_data;
> + int r;
> +
> + clk_data = mtk_alloc_clk_data(CLK_BDP_NR);
> +
> + mtk_clk_register_gates(node, bdp_clks, ARRAY_SIZE(bdp_clks),
> + clk_data);
> +
> + r = of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
> + if (r)
> + pr_err("%s(): could not register clock provider: %d\n",
> + __func__, r);
> +}
[...]
> +
> +static int __init clk_probe(struct platform_device *pdev)
> +{
> + void (*clk_init)(struct device_node *);
> + const struct of_device_id *of_id;
> +
> + of_id = of_match_node(of_clk_match_tbl, pdev->dev.of_node);
> + if (!of_id || !of_id->data)
> + return -EINVAL;
> +
> + clk_init = of_id->data;
> + clk_init(pdev->dev.of_node);
> +
> + return 0;
> +}
> +
> +static struct platform_driver clk_drv = {

Please add some mtk here, 'clk_drv' is too generic.

> + .driver = {
> + .name = "mtk-clk",
> + .owner = THIS_MODULE,

This is unnecessary.

> + .of_match_table = of_match_ptr(of_clk_match_tbl),

Just drop of_match_ptr() because it's not helping. Also
of_clk_match_tbl is too generic.

> + },
> +};
> +
> +builtin_platform_driver_probe(clk_drv, clk_probe);
> +}
> diff --git a/drivers/clk/mediatek/clk-mtk.h b/drivers/clk/mediatek/clk-mtk.h
> index 32d2e45..8796acc 100644
> --- a/drivers/clk/mediatek/clk-mtk.h
> +++ b/drivers/clk/mediatek/clk-mtk.h
> @@ -145,8 +146,35 @@ struct mtk_gate {
[...]
> +struct mtk_clk_divider {
> + int id;
> + const char *name;
> + const char *parent_name;
> + unsigned long flags;
> +
> + uint32_t div_reg;

u32 is shorter

> + unsigned char div_shift;
> + unsigned char div_width;
> + unsigned char clk_divider_flags;
> + const struct clk_div_table *clk_div_table;
> +};
--
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