[alsa-devel] [PATCH 2/8] ASoC: samsung: i2s: Ensure names of supplied clocks are unique

[Krzysztof Kozlowski]

On Mon, Feb 5, 2018 at 4:43 PM, Sylwester Nawrocki
<s.nawrocki at samsung.com> wrote:
> In order to support multiple instances of the I2S IP block the platform
> device name is prepended to each clock registered by the driver.
> The clock-output-names property is now not used, this should not cause
> any issues as, for example, CDCLK clock is referenced through DT 'clocks'
> property, not by name.
>
> This change allows to have both I2S0 and I2S1 enabled simultaneously
> on exynos5433 and working properly when #clock-cells property is specified
> in respective DT nodes.
>
> Signed-off-by: Sylwester Nawrocki <s.nawrocki at samsung.com>
> ---
>  sound/soc/samsung/i2s.c | 25 ++++++++++++++++---------
>  1 file changed, 16 insertions(+), 9 deletions(-)
>
> diff --git a/sound/soc/samsung/i2s.c b/sound/soc/samsung/i2s.c
> index aeba0ae890ea..b7d25a63da8b 100644
> --- a/sound/soc/samsung/i2s.c
> +++ b/sound/soc/samsung/i2s.c
> @@ -1193,11 +1193,13 @@ static void i2s_unregister_clock_provider(struct platform_device *pdev)
>
>  static int i2s_register_clock_provider(struct platform_device *pdev)
>  {
> -       struct device *dev = &pdev->dev;
> -       struct i2s_dai *i2s = dev_get_drvdata(dev);
> +       const char * const i2s_clk_desc[] = { "cdclk", "rclk_src", "prescaler" };
>         const char *clk_name[2] = { "i2s_opclk0", "i2s_opclk1" };
>         const char *p_names[2] = { NULL };
> +       struct device *dev = &pdev->dev;
> +       struct i2s_dai *i2s = dev_get_drvdata(dev);
>         const struct samsung_i2s_variant_regs *reg_info = i2s->variant_regs;
> +       const char *i2s_clk_name[ARRAY_SIZE(i2s_clk_desc)];
>         struct clk *rclksrc;
>         int ret, i;
>
> @@ -1214,30 +1216,35 @@ static int i2s_register_clock_provider(struct platform_device *pdev)
>                 clk_put(rclksrc);
>         }
>
> +       for (i = 0; i < ARRAY_SIZE(i2s_clk_desc); i++)
> +               i2s_clk_name[i] = devm_kasprintf(dev, GFP_KERNEL, "%s_%s",
> +                                               dev_name(dev), i2s_clk_desc[i]);

kasprintf() might return NULL and later it is being used as clock
name. I think you should handle such error.

Best regards,
Krzysztof

> +
>         if (!(i2s->quirks & QUIRK_NO_MUXPSR)) {
>                 /* Activate the prescaler */
>                 u32 val = readl(i2s->addr + I2SPSR);
>                 writel(val | PSR_PSREN, i2s->addr + I2SPSR);
>
>                 i2s->clk_table[CLK_I2S_RCLK_SRC] = clk_register_mux(dev,
> -                               "i2s_rclksrc", p_names, ARRAY_SIZE(p_names),
> +                               i2s_clk_name[CLK_I2S_RCLK_SRC], p_names,
> +                               ARRAY_SIZE(p_names),
>                                 CLK_SET_RATE_NO_REPARENT | CLK_SET_RATE_PARENT,
>                                 i2s->addr + I2SMOD, reg_info->rclksrc_off,
>                                 1, 0, i2s->lock);
>
>                 i2s->clk_table[CLK_I2S_RCLK_PSR] = clk_register_divider(dev,
> -                               "i2s_presc", "i2s_rclksrc",
> +                               i2s_clk_name[CLK_I2S_RCLK_PSR],
> +                               i2s_clk_name[CLK_I2S_RCLK_SRC],
>                                 CLK_SET_RATE_PARENT,
>                                 i2s->addr + I2SPSR, 8, 6, 0, i2s->lock);
>
> -               p_names[0] = "i2s_presc";
> +               p_names[0] = i2s_clk_name[CLK_I2S_RCLK_PSR];
>                 i2s->clk_data.clk_num = 2;
>         }
> -       of_property_read_string_index(dev->of_node,
> -                               "clock-output-names", 0, &clk_name[0]);
>
> -       i2s->clk_table[CLK_I2S_CDCLK] = clk_register_gate(dev, clk_name[0],
> -                               p_names[0], CLK_SET_RATE_PARENT,
> +       i2s->clk_table[CLK_I2S_CDCLK] = clk_register_gate(dev,
> +                               i2s_clk_name[CLK_I2S_CDCLK], p_names[0],
> +                               CLK_SET_RATE_PARENT,
>                                 i2s->addr + I2SMOD, reg_info->cdclkcon_off,
>                                 CLK_GATE_SET_TO_DISABLE, i2s->lock);
>
> --
> 2.14.2
>