2016-03-21 20:12:20

by Bhuvanchandra DV

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

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.

Signed-off-by: Bhuvanchandra DV <[email protected]>
---
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);

--
2.7.3

2016-03-23 06:38:18

by Stefan Agner

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

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 <[email protected]>

>
> Signed-off-by: Bhuvanchandra DV <[email protected]>
> ---
> 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);