Re: [PATCH] spi: fsl-dspi: Set max_speed_hz for master

From	Stefan Agner <stefan@agner.ch>
Newsgroups	linux.kernel
Subject	Re: [PATCH] spi: fsl-dspi: Set max_speed_hz for master
Date	2016-03-23 07:40 +0100
Message-ID	<rfKCu-7Xl-7@gated-at.bofh.it> (permalink)
References	<rfesW-2eY-21@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On 2016-03-21 13:11, Bhuvanchandra DV wrote:
> Calculate and update max speed from bus clock for SoC's
> using DSPI IP.
> 
> The bus clock factor's are taken from the data sheet's
> of respective SoC's.

Plurals are without apostrophe...

I wonder if GCC optimizes this to a bit shift...

Acked-by: Stefan Agner <stefan@agner.ch>

> 
> Signed-off-by: Bhuvanchandra DV <bhuvanchandra.dv@toradex.com>
> ---
>  drivers/spi/spi-fsl-dspi.c | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
> index 59a1143..8753276 100644
> --- a/drivers/spi/spi-fsl-dspi.c
> +++ b/drivers/spi/spi-fsl-dspi.c
> @@ -121,18 +121,22 @@ enum dspi_trans_mode {
>  
>  struct fsl_dspi_devtype_data {
>  	enum dspi_trans_mode trans_mode;
> +	u8 max_clock_factor;
>  };
>  
>  static const struct fsl_dspi_devtype_data vf610_data = {
>  	.trans_mode = DSPI_EOQ_MODE,
> +	.max_clock_factor = 2,
>  };
>  
>  static const struct fsl_dspi_devtype_data ls1021a_v1_data = {
>  	.trans_mode = DSPI_TCFQ_MODE,
> +	.max_clock_factor = 8,
>  };
>  
>  static const struct fsl_dspi_devtype_data ls2085a_data = {
>  	.trans_mode = DSPI_TCFQ_MODE,
> +	.max_clock_factor = 8,
>  };
>  
>  struct fsl_dspi {
> @@ -726,6 +730,9 @@ static int dspi_probe(struct platform_device *pdev)
>  	}
>  	clk_prepare_enable(dspi->clk);
>  
> +	master->max_speed_hz =
> +		clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
> +
>  	init_waitqueue_head(&dspi->waitq);
>  	platform_set_drvdata(pdev, master);

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[PATCH] spi: fsl-dspi: Set max_speed_hz for master Bhuvanchandra DV <bhuvanchandra.dv@toradex.com> - 2016-03-21 21:20 +0100
  Re: [PATCH] spi: fsl-dspi: Set max_speed_hz for master Stefan Agner <stefan@agner.ch> - 2016-03-23 07:40 +0100

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