[PATCH v2 2/2] clk: davinci: psc-dm365: fix few clocks
David Lechner
david at lechnology.com
Tue May 15 08:36:58 PDT 2018
On 05/15/2018 06:22 AM, Sekhar Nori wrote:
> Fix parent of EMAC and voice codec PSC clocks. Documentation is clear
> on EMAC clock parent, but its not fully clear on parent of voice codec
> clock. The implementation chosen is matches arch/arm/mach-davinci/dm365.c.
> Add a comment explaining this for posterity.
>
> There is only one power domain on DM365. Fix the power domain of voice
> codec and vpss dac modules.
>
> While at it, add a comment explaining how the parent of vpss dac clock was
> derived. Note that this patch does not touch the parent of vpss dac clock.
>
> Signed-off-by: Sekhar Nori <nsekhar at ti.com>
> ---
> v2: add comments explaining parents of voice codec and vpss dac clocks
>
> drivers/clk/davinci/psc-dm365.c | 19 ++++++++++++++++---
> 1 file changed, 16 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/clk/davinci/psc-dm365.c b/drivers/clk/davinci/psc-dm365.c
> index 3ad915f37376..289af3913fb0 100644
> --- a/drivers/clk/davinci/psc-dm365.c
> +++ b/drivers/clk/davinci/psc-dm365.c
> @@ -65,9 +65,22 @@ static const struct davinci_lpsc_clk_info dm365_psc_info[] = {
> LPSC(31, 0, arm, pll2_sysclk2, NULL, LPSC_ALWAYS_ENABLED),
> LPSC(38, 0, spi3, pll1_sysclk4, spi3_clkdev, 0),
> LPSC(39, 0, spi4, pll1_auxclk, spi4_clkdev, 0),
> - LPSC(40, 0, emac, pll2_sysclk4, emac_clkdev, 0),
> - LPSC(44, 1, voice_codec, pll1_sysclk3, voice_codec_clkdev, 0),
> - LPSC(46, 1, vpss_dac, pll1_sysclk3, vpss_dac_clkdev, 0),
> + LPSC(40, 0, emac, pll1_sysclk4, emac_clkdev, 0),
> + /*
> + * The TRM (ARM Subsystem User's Guide) shows two clocks input into
> + * voice codec module (PLL2 SYSCLK4 with a DIV2 and PLL1 SYSCLK4). Its
> + * not fully clear from documentation which clock should be considered
> + * as parent for PSC. The clock chosen here is to maintain
> + * compatibility with existing code in arch/arm/mach-davinci/dm365.c
> + */
> + LPSC(44, 0, voice_codec, pll2_sysclk4, voice_codec_clkdev, 0),
> + /*
> + * Its not fully clear from TRM (ARM Subsystem User's Guide) as to what
> + * the parent of VPSS DAC LPSC should actually be. PLL1 SYSCLK3 feeds
> + * into HDVICP and MJCP. The clock chosen here is to remain compatible
> + * with code existing in arch/arm/mach-davinci/dm365.c
> + */
> + LPSC(46, 0, vpss_dac, pll1_sysclk3, vpss_dac_clkdev, 0),
> LPSC(47, 0, vpss_master, pll1_sysclk5, vpss_master_clkdev, 0),
> LPSC(50, 0, mjcp, pll1_sysclk3, NULL, 0),
> { }
>
Reviewed-by: David Lechner <david at lechnology.com>
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