[v3,7/9] spi: spi-s3c64xx: Ensure cur_speed holds actual clock value

Commit Message

Lukasz Stelmach Oct. 2, 2020, 12:22 p.m. UTC

Make sure the cur_speed value used in s3c64xx_enable_datapath()
to configure DMA channel and in s3c64xx_wait_for_*() to calculate the
transfer timeout is set to the actual value of (half) the clock speed.

Don't change non-CMU case, because no frequency calculation errors have
been reported.

Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Suggested-by: Tomasz Figa <[e-mail]>
Signed-off-by: Łukasz Stelmach <[e-mail]>
---
 drivers/spi/spi-s3c64xx.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Krzysztof Kozlowski Oct. 2, 2020, 12:31 p.m. UTC | #1

On Fri, Oct 02, 2020 at 02:22:41PM +0200, Łukasz Stelmach wrote:
> Make sure the cur_speed value used in s3c64xx_enable_datapath()
> to configure DMA channel and in s3c64xx_wait_for_*() to calculate the
> transfer timeout is set to the actual value of (half) the clock speed.
> 
> Don't change non-CMU case, because no frequency calculation errors have
> been reported.
> 
> Reviewed-by: Krzysztof Kozlowski <[e-mail]>
> Suggested-by: Tomasz Figa <[e-mail]>
> Signed-off-by: Łukasz Stelmach <[e-mail]>

For the future, tags are added in chronological order, so first is
suggested (as someone suggested to make a patch), then your SoB (as you
wrote it) and then my review (because you had to write a patch before I
could review).

All other patches here have these mixed up. No need to resend, but keep
it in mind for the future.

Best regards,
Krzysztof

Patch

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index f85f40fd608c..0bd3e230350c 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -626,6 +626,7 @@  static int s3c64xx_spi_config(struct s3c64xx_spi_driver_data *sdd)
 		ret = clk_set_rate(sdd->src_clk, sdd->cur_speed * 2);
 		if (ret)
 			return ret;
+		sdd->cur_speed = clk_get_rate(sdd->src_clk) / 2;
 	} else {
 		/* Configure Clock */
 		val = readl(regs + S3C64XX_SPI_CLK_CFG);