[PATCH 3/5] spi: s3c64xx: support custom value of internal clock divider
Krzysztof Kozlowski
krzysztof.kozlowski at linaro.org
Mon Jun 27 02:40:50 PDT 2022
On 27/06/2022 08:47, Chanho Park wrote:
> Modern exynos SoCs such as Exynos Auto v9 has different internal clock
> divider, for example "4". To support this internal value, this adds
> clk_div of the s3c64xx_spi_port_config and use it if it is specified.
> Otherwise, use "2" which is the previous default value.
>
> Signed-off-by: Chanho Park <chanho61.park at samsung.com>
> ---
> drivers/spi/spi-s3c64xx.c | 23 +++++++++++++++--------
> 1 file changed, 15 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
> index e17c74c0d7de..dd5fc8570bce 100644
> --- a/drivers/spi/spi-s3c64xx.c
> +++ b/drivers/spi/spi-s3c64xx.c
> @@ -131,6 +131,7 @@ struct s3c64xx_spi_dma_data {
> * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS register.
> * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
> * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
> + * @clk_div: Internal clock divider, if not specified, use 2 as the default.
> * @quirks: Bitmask of known quirks
> * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
> * @clk_from_cmu: True, if the controller does not include a clock mux and
> @@ -148,6 +149,7 @@ struct s3c64xx_spi_port_config {
> int rx_lvl_offset;
> int tx_st_done;
> int quirks;
> + int clk_div;
> bool high_speed;
> bool clk_from_cmu;
> bool clk_ioclk;
> @@ -620,6 +622,7 @@ static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
> void __iomem *regs = sdd->regs;
> int ret;
> u32 val;
> + u32 div = sdd->port_conf->clk_div ? sdd->port_conf->clk_div : 2;
I would prefer to explicitly set '2' as clk_div for existing variants.
Such assignments in the code are usually trickier to find/read.
>
Best regards,
Krzysztof
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